Regulatory Guide 1.132: Difference between revisions

Site Investigations for Foundations of Nuclear Power Plants
	ML13350A266
Person / Time
Issue date:	09/30/1977
From:	; NRC/OSD
To:	;
References
	RG-1.132
	Download: ML13350A266 (30)
	v • d • e

Revision as of 10:17, 4 November 2019

U.S. NUCLEAR REGULATORY COMMISSION September 1977

0-0

)REGULATORY GUIDE

OFFICE OF STANDARDS DEVELOPMENT

REGULATORY GUIDE 1.132 SITE INVESTIGATIONS FOR FOUNDATIONS

OF NUCLEAR POWER PLANTS

A. INTRODUCTION

programs as well as specific guidance for conducting Appendix A, "Seismic and Geologic Siting Criteria subsurface investigations, the spacing and depth of for Nuclear Po%%er Plants." to 10 CFR Part 100, borings, and sampling. Appendix A provides defini-

"'Reactor Site Criteria," establishes requirements for lions for some of the terms used in this guide. These conducting site investigations to permit an evaluation terms are identified in the text by anasterisk. Appen- of the site and to provide information needed for dix B tabulates methods of conducting subsurface in- seismic response analyses and engineering design. Re- vestigations. and Appendix C gives cfiteria for the quirements include the development of geologic in- spacing and depth of borings.for.safety-related struc- lures in regions of favorable or-uniform conditions.

formation relevant to the stratigraphy. lithology. eeecsLtdih.tx n geologic history, and structural geology of the site References cited in'.he text and appendices are listed and the evaluation of the engineering properties of in Appendix D.., Appendix E contains a subsurface materials, bibliogr.aphical.liting oLreated material.

Safety-related site characteristics are identified in . DISCUSSION

detail in Rcgulatory Guide 1.70. "Standard For- l.,Cenera.,

mat and Content of Safety Analysis Reports for Sii'6i'inve.itigations for nuclear power plants are

Nuclear Power Plants." Regulatory' Guide 4.7. sar* to determine the geotechnical charac- e.*sne

"General Site Suitability Criteria for Nuclear Poyer ,;eristics of a site that affect the design, performance, Stations," discusses major site characteristics thi'a- ,and afety of plants. The investigations produce the feet site suitabilitv. ... . information needed to define the overall site geology This guide describes programs of sitiinv stihtions that is necessary for an understanding of subsurface that would normally meet the needifor evalua[ing conditions and for identifying potential geologic and the safety of the site from the standpý'int of*hfe per- earthquake hazards that may exist at the site.

formance of foundations and earthwor'46&er most Investigations for hazards such as faulting.

anticipated loading conditions, including earth- landslides, cavernous rocks, ground subsidence, and quakes. It also describe.6 ite investigations required soil liquefaction are especially important.

to evaluate geotec hlical,*laramcters needed, for engineering anffy1.i$ Ma, deslgn. The site investiga- Site investigations also provide information needed tions discus in*Us Nide are applicable ind to both to define local foundation and groundwater condi- land uandi.cfflo~re si;. S' This guide does not deal with t tosa ions as well as the geotechnical parameters needed hydr Ai.i lions, except for groundwater for engineering analysis and design of foundations icasu _"Its, nor does . it discuss geophysical and earthworks. Geotechnical parameters needed for

iethodlM subsurface exploration. analysis and design include, but are not limited to.

IV those used to evaluate the bearing capacity o' foun- This guide provides general guidance and recom- dation materials, lateral earth pressures against walls.

mend'ations for developing site-specific investigation the stability of cuts and slopes in soil and rock. the ef- USNRC REGULATORY GUIDES CooIMo-iit Q106111iI. -. 'It ft, If-. -I.,tv 1i.11.- C. .tn'-'s, Ujýj N-iI'. "It

-I,

Reu ir Guw. wei. lia'leIi mun' ufewnix'b i natlke t'.ivlalbli! to tht! public methods Leloitv C...... r) ..V.Ni-troi'v,. 1) C. 20 f;, At iiiio

'....... I ttajInlS*t'

1 tCCelitalie. to to.' NRC %iff, Pl'ti~~i'ie stCic iit Vliti of the Cows, v~ains equlatt~oiri. to d.,fnieasi teh". ht t tatLv t h. ital ,n t'.ahl.z~tnq soccii~c~l problenti Th,-uil, %. ,,it ...th-' 10 twi. li.'.wl

1i~,i~ iuas It suisi111l1itIs,Cuftt-l%. Of i ittIa i giltiaI.nC" let J1tltiiCrinht. Rgu~ljustv u-df- Mýuhiidt tanl :, UI'~l0

T 1,difll'fnt I isis thin"tl " UIouin lbmeqoalIM wall be- accetil 7. fl eit rh .i-iI "a7faaca 7. TPI,l'ViiWe..t InS

.iftle it fthoy lriaval! J1( eAr for the,5 fiuolfut rtlluitii. lit Ifil, isisin.tce of conl~nasince 3 Vrash tnil Mm. wmi Trtalcia- ftOcatalort filitfa of at wirtsil r licesne lv vhe Comnnswn'ii. 'I nsinr.stfa' 1 SaImli9 tt atl.s'u Cjfmminti loiii ind %uiiio .- t'th'."to t1O! ia'"A'a.i CinmtflS nl uprw n..1 [ ni i-1,'

in... tMuth ii.jI.'.I 'u, c Ini~ivsi.n W -111W.11111t W

11 ta e. inlQifo,"'.~ Iiteat'l .15 .s iftiia tim

. .c

-ia iinillit.-f Clthitafs tOO1 n .t s1,......

I. rat, s . I~

q%,ai Ilt iwt ni-r I.ta'csu

0ie 'l t i ia tcim.','fl i hin'tifliiiiiii w t'i ivitth al'-t'rC Its liva~ aniit wifes to-i'ia ,"nm

,,*I~u~~ .tI4" liiiiis h . th inthiutm nl I" t 'U

,,,i Si.aoi' htt.t'a"S i sn a.

t .' etvthai ft- ru ,ili.ni hs......

tit a'S'Saa1amr.' Ii" a.gstas JlijllIi ii.a, iis'rtaI i;iI'US:a U -ill *Caa',a .a...;aifa

()it........... -

fect of earthquake-induced motions through underly- ing deposits on the response of soils and structures ,*

b. State government agencies such as the State Geological Survey,

0I

(including the potential for inducing liquefaction in soils). and those needed to estimate the expected set- c. U.S. Government agencies such as the U.S.

Geological Survey and the U.S. Army Corps of tement of structures. Geotechnical parameters arc also needed for analysis and design of plant area fills, Engineers.

structural fills, backfills. and earth and rockfill dams.

d. Topographic maps.

dikes, and other water retention or flood protection structures.

e. Geologic and geophysical maps, Site information needed to assess the functional in. " f. Engineering geologic maps.

tegrity of foundations with respect to geologic and geotechnical considerations include: g. Soil survey maps.

a. The geologic origin, types, thicknesses. se. " Ih. Geologic reports and other geological quence. depth. location, and areal extent of soil ant literature, rock strata and the degree and extent of theii i. Geotechnical reports and other geotechnical weathering:

literature.

h. Orientation and characteristics of foliations bedding. jointing, a !d faulting in rock, j. Well records and water supply reports.

c. Groundwater c,,nditions: k. Oil well records.

d. The static and dynamic engineering proper I. Hydrologic maps.

ties of subsurface materials:

m. Hydrologic and tidal data and flood records, e. Information regarding the results of in vestigations of' adverse geological conditions such a,s n. Climate and rainfall records.

cavities, joints, faults. fissures. or unfavorable soi conditions: o. Mining history, old mine plans. and sub- sidence records.

f. Information related to man's activities such a withdrawal of fluids from or addition of fluids to th C p. Seismic data and historical earthquake subsurface, extraction of minerals, or loading effect s records.

of dams or reservoirs: and q. Newspaper records of landslides, floods.

g. Information detailing any other geologic con - earthquakes. subsidence, and other events oflgeologic dition discovered at the site that may affect the desig n or geotechnical significance, or performance of the plant or the location of struc tures. r. Records of performance of other structures in the vicinity, and

2. Reconnaissance Investigations and Literatur e Reviews s. Personal communication with local inhabi- tants and local professionals.

Planning of subsurface investigations and the ii Special or unusual problems such as swelling soils terpretation of data require thorough understandir Ig and shales (subject to large volume changes with of the general geology of the site. This can be ol b- changes in moisture), occurrences of gas, cavities in rained by a reveiw. either preceding or accompanyir Ig soluble rocks, subsidence caused by mining or pump- the subsurface investigation, of available documeiI- ing ofwater. gas. or oil from wells, and possible uplift tary materials and results of previous investigation s. due to pressurization from pumping of water, gas, or In most cases, a preliminary study of the site geolol d oil into the subsurface may require consultation with can be done by review of existing current an)d individuals, institutions, or firms having experience historical documentary materials and by study of in the area with such problems.

aerial photographs and other remote sensir imagery. Possible sources of current and historic al The site investigation includes detailed surface ex- documentary information may include: ploration of the immediate site area and adjacent en- virons. Further detailed surface exploration also may a. Geology and engineering departments of be required in areas remote to the immediate plant State and loce! universities, site to complete the geologic evaluation of the site or

1.132-2

-- M

a

to conduct detailed investigations of surface faulting between aquifers. The occurrence of artesian pressure or other features. Surface exploration needed for the in borings should be noted on boring logs. and their assessment of the site geology is site dependent and heads should be measured and logged.

may be carried out with the use of any appropriate combination of geological, geophysical (seismic Where construction dewatering is required, refraction), or engineering techniques. Normally this piezometers or observation wells should be used dur- includes the following: ing construction to monitor the groundwater surface and pore pressures beneath the excavation and in the adjacent ground. The guide does not cover a. Detailed mapping of topographic, groundwater monitoring needed during construction hydrologic, and surface geologic features, as ap- in plants that have permanent dewatering systems in- propriate for the particular site conditions, with corporated in their design.

scales and contour intervals suitable for analysis and engineering design. For offshore sites, coastal sites, or sites located near lakes or rivers this includes topography and detailed hydrographi, surveys to the extent that they are needed for site evaluation and 4. Subsurface Investigations engineering design.

a. General b. Detailed geologic interpretations of aerial photographs and other remote-sensing imagery, as The appropriate depth, layout, spacing. and sampl- appropriate for the particular site conditions, to as- ing requirements for subsurface investigations are sist in identifying rock outcrops, soil conditions, dictated by the foundation requirements and by the evidence of past landslides or soil liquefaction, faults, complexity of the subsurface conditions. Methods of fracture traces, and lineaments. conducting subsurface investigations are tabulated in Appendix B, and criteria for the spacing and depth of c. Detailed onsite mapping of local engineering borings for safety-related structures, where favorable geology and soils. or uniform geologic conditions exist. are given in Ap- pendix C.

d. Mapping of surface water features such as rivers, streams, or lakes and local surface drainage Subsurface explorations for less critical founda- channels, ponds, springs, and sinks at the site. tions of power plants should be carried out with spac- ing and depth of penetration as necessary to define the general geologic and foundation conditions of the site. Subsurface investigations in areas remote from

3. Groundwater Investigations plant foundations may be needed to complete the geologic description of the site and confirm geologic Knowledge of groundwater conditions. their and foundation conditions and should also be relationship to surface waters, and variations as- carefully planned.

sociated with seasons or tides is needed for founda- tion analyses. Groundwater conditions should be Subsurface conditions may be considered observed in borings at the time they are made: favorable or uniform if the geologic and stratigraphic however, for engineering applications, such data features to be defined can be correlated from one bor- must be supplemented by groundwater observations ing or sounding* location to the next with relatively made by means of properly installed wells or smooth variations in thicknesses or properties of the piezometers* that are read at regular intervals from geologic units. An occasional anomaly or a limited the time of their installation at least through the con- number of unexpected lateral variations may occur.

struction period. The U.S. Army Corps of Engineers' Uniform conditions permit the maximum spacing of manual on groundwater and pore pressure observa- borings for adequate definition of the subsurface con- tions in embuinkment dams and their foundations ditions at the site.

(Ref. I) provides guidance on acceptable mrthods for the installation and maintenance of piezometer and Occasionally soil or rock deposits may be en- observation well* instrumentation. Piezometer or countered in which the deposition patterns are so well installations should be made in as many loca- complex that only the major stratigraphic boundaries tions as needed to define groundwater conditions. are correlatable, and material types or properties may When the possibility of perched groundwater tables vary within major geologic units in an apparently or artesian pressures is indicated by borings or other random manner from one boring to another. The evidence, piezometer installation should be made to number and distribution of borings needed for these measure each piezometric level independently. Care conditions will exceed those indicated in Appendix C

should be taken in the design and installation of and are determined by the degree of resolution piezometers to prevent hydraulic communication needed in the definition of foundation properties.

1.132-3

The cumulative thicknesses of the various material b. lnvestigations Related to SpeciflC Site Conditions types, their degree of variability, and ranges of the material properties must be defined. Investigations for specific site conditions should in- clude the following:

If there is evidence suggesting the presence of local adverse anomalies or discontinuities such as cavities.

sinkholes, fissures, faults, brecciation. and lenses or (I) Rock. The engineering characteristics of pockets of unsuitable material, supplementary bor- rocks are related primarily to their structure. bed- ings or soundings at a spacing small enough to detect ding. jointing, fracturing, weathering, and physical and delineate these features are needed. It is impor- properties. Core samples are needed to observe and tant that these borings should penetrate all suspect define these features. Suitable coring methods should zones or extend to depths below which their presence be employed in sampling, and rocks should be would not influence the safety of the structures. sampled to a depth below which rock characteristics Geophysical investigations may be used to supple- do not influence foundation performance. Deeper ment the boring and sounding program. borings'mav be needed to investigate zones critical to the evaluation of the site geology. Within the depth intervals influencing foundation performance. zones in planning the exploration program for a site, of poor core recovery, low RQD (Rock Quality consideration should also be given to the possibility Designation).* dropping of rods. lost drilling fluid that the locations of structures may be changed, and circulation. zones requiring casing. and other zones that such changes may require additional exploration where drilling difficulties are encountered should be to adequately define subsurface conditions at the investigated by means of suitable logging or in situ final locations. observation methods to determine the nature.

The location and spacing of borings, soundings. geometry. and spacing of any discontinuities or and exploratory excavations should be chosen anomolous zones. %%'here soil-filled voids, channels, carefully to adequately define subsurface conditions. or fissures are encountered. representative samples*

A uniform grid may not provide the most effective of the filling materials are needed. Where there is distribution of exploration locations unless the site evidence of significant residual stresses, they should conditions are very uniform. The location of initial be evaluated on the basis of in situ stress or strain borings should be determined on the basis of condi- measurements.

tions indicated by preliminary investigations. Loca- tions for subsequent or supplemental explorations (2) Granular Soils. Investigations of granular should be chosen in a manner so as to result in the soils should include borings with splitspoon sampling best definition of the foundation conditions on the and Standard Penetration Tests with sufficient basis of conclusions derived from earlier exploratory coverage to define the soil profile and variations of work. soil conditions. Soundings with cone penetration tests may also be used to provide useful supplemental Whereve feasible, the locations of subsurface ex- data if the device is properly calibrated to site condi- plorations should be chosen to permit the construc- tions.

tion of geological cross sections in important subsur- face views of the site.

Suitable samples should be obtained for soil iden- It is essential to verify during construction that in tification and classification, in situ density determina- situ conditions have been realistically estimated dur- tions. mechanical analyses, and anticipated ing analysis and design. Excavations made during laboratory testing. In these investigations, it is impor- construction provide opportunities for obtaining ad- tant to obtain the best possible undistrbed samples*

ditional geologic and geotechnical data. All construc- for testing to determine whether the sands are suf- tion excavations for safety-related structures and ficiently dense to preclude liquefaction or damaging other excavations important to the verification of cyclic deformation. The number and distribution of subsurface conditions should be geologically mapped samples will depend on testing requirements and the and logged in detail. Particular attention should be variability of the soil conditions. In general, however, given to the identification of thin strata or other samples should be included from at least one prin- geologic features that may be important to founda- cipal boring* at the location of each Category I struc- tion behavior but. because of their limited extent, ture. Samples should be obtained at regular intervals were previously undetected in the investigations in depth and when changes in materials occur.

program. If subsurface conditions substantially differ Criteria for the distribution of samples are given in from those anticipated, casting doubt on the ade- regulatory position 5.

quacy of the design or expected performance of the foundation. there may be a need for additional ex- Granular soils containing coarse gravels and ploration and redesign.

U

boulders are among the most difficult materials to

.132-4

sample. Obtaining good quality samples in these sometimes be necessary to inspect the rock after strip- coarser soils often requires the use of trenches, pits. ping or excavation is complete and the rock is ex- or other accessible excavations* into the zones of in- posed. Remedial grouting or other corrective terest. Also, extreme care is necessary in interpreting measures should be employed where necessary.

results from $he Standard Penetration Test in these materials. Often such data are misleading and may (5) Materials Lb.suitahhle Jbr Fotmdatitnhs. Bor- have to be disregarded. When sampling of these ings and representative sampling and testing should coarse soils is difficult. informationthat may be lost be completed to delineate the boundaries of un- when the soil is later classified in the lhboratory suitable materials, These boundaries should be used should be recorded in the field. This information to define the required excavation limits.

should include observed estimates of percent cobbles, boulders, and coarse material and their hardness. (6) Borrow Materials. Exploration of borrow shape, surface coating. and degree of weathering of sources requires the determination of the location coarse materials. and amount of borrow fill materials available.

Investigations in the borrow areas should be of suf- ficient hori.,;mal and vertical intervals small enough

(3) Moderatelyv Compressible or Normally Con- to determine the material variability and should in- solidated Clay' or Clayve Soils. The properties of a clude adequate sampling of representative materials fine grained soil are related to its in situ structure.* for laboratory testing.

and therefore the recovery and testing of good un- c. Sam...nt disturbed samples are necessary. Criteria for the dis- tribution and methods for obtaining undisturbed samples are discussed in regulatory position 5. All soil and rock samples obtained for testing should be representative. In many cases, to establish

(4) Stibsurjaice Cavilies. Subsurface cavities may physical properties it is netcssary to obtain un- occur in water-soluble rocks. lavas, or weakly in- disturbed samples that preserve the in situ structure durated sedimentary rocks as the result of subterra- of the soil. The recovery of undisturbed samples is nean solutioning and erosion. Because of the wide discussed in Section B.6 of this guide.

distribution of carbonate rocks in the United States.

the occurrence of features such as cavities, sinkholes. Sampling of soils should include. as a minimum.

and solution-widened joint openings is common. For recovery of samples for all principal borings at this reason, it is best to thoroughly investigate any regular intervals and at changes in strata. A number site on carbonate rock for solution features to deter- of samples sufficient to permit laboratory determina- mine their influence on the performance of founda- tion of average material properties and to indicate tions. their variability is necessary. Alternating splitspoon and undi!;Iurbed samples with depth is recom- Investigations may be carried out with borings mended. Where sampling is not continuous, the alone or in conjunction with accessible excavations, elevations at which samples are taken should be stag- soundings, pumping tests, pressure tests, geophysical gered from boring to boring so as to provide con- surveys, or a combination of such methods. The in- tinuous coverage of samples within the soil column.

vestigation program will depend on the details of the In supplementary borings,* sampling may be con- site geology and the foundation design. fined to the zone of specific interest.

Indications of the presence of cavities, such as Relatively thin zones of weak or unstable soils may zones of lost drilling fluid circulation, water flo\%ing be contained within more competent materials and into or out of drillholes, mud fillings, poor core may affect the engincering properties of the soil or recovery, dropping or settling of drilling rods. rock. Continuous sampling in subsequent borings is anomalies in geophysical surveys, or in situ tests that needed through these suspect zones. Where it is not suggest voids, should be followed up with more possible to obtain continuous samples in a single bor- detailed investigations. These investigations should ing. samples may be obtained from adjacent closely include excavation to expose solution features or ad- spaced borings in the immediate vicinity and may be ditional borings that trace out such features. used as representative of the material in the omitted depth intervals. Such a set of borings should be con- The occurrence, distribution, and geometry of sub- sidered equivalent to one principal boring.

surface cavities are highly unpredictable, and no preconstruction exploration program can ensure that all significant subsurface voids will be fully revealed. d. Determining the Engineering Properties of Sub- Experience has shown that solution features may re- surface Materials main undetected even where the area has been in-

0 vestigated by a large number of borings. Therefore, where a site is on solution-susceptible rock, it may The shear strengths of foundation materials in all zones subjected to significant imposed stresses must

1.132-5

- - I

be determined to establish whether they are adequate should also be determined with an accuracy of +/-0. I

to support the imposed loads with an appropriate ft. Deviation surveys should be run in all boreholes margin of safety. Similarly, it is necessary both to that are used for crosshole seismic tests and in all determine the compressibilities and swelling poten- boreholes where deviations are significant to the use tials of all materials in zones subjected to significant of data obtained. After use, it is advisable to grout changes of compressive stresses and to establish that each borehole with cement to prevent vertical move- the deformations will be acceptable. In some cases ment of groundwater in the borehole.

these determinations may be made by suitable in situ tests and classification tests. Other situations may re- quire the laboratory testing of undisturbed samples. 6. Recovery of Undisturbed Soil Samples Determination of dynamic modulus and damping values for soil strata is required 'or earthquake The best undisturbed samples are often obtained response analyses. These determinations may be by carefully performed hand trimming of block sam- made by laboratory testing of suitable undisturbed pies in accessible excavations. However, it is normal- samples in conjunction with appropriate in situ tests. ly not practical to obtain enough block samples at the requisite spacings and depths by this method alone. It

5. Methods and Procedures for ExpLuratory Drilling is customary, where possible, to use thin-wall tube samplers in borings for the major part of the un- In nearly ever%, site investigation, the primary disturbed sampling. Criteria for obtaining un- means Of subsurface exploration are borings and disturbed tube samples are given in regulatory posi- borehole sampling. Drilling methods and procedures tion 5.

should be compatible with sampling requirements and the methods of sample recovery. The recovery of undisturbed samples of good quality is dependent on rigorous attention to details The top of the hole should be protected by a or equipment and procedures. Proper cleaning of the suitable surface casing where needed. Below ground hole. by methods that do not produce avoidable dis- surface, the borehole should be protected by drilling turbance of the soil, is necessary before sampling.

mud or casing. as necessary, to prevent caving and The sampler should be advanced in a manner that disturbance of materials to be sampled. The use of does not produce avoidable disturbance. For exam- drilling mud is preferred to prevent disturbance when ple, when using fixed-piston-type samplers. the drill- obtaining undisturbed samples of granular soils. ing rig should be firmly anchored, or the piston However, casing may be used if proper steps are should be fixed to an external anchor, to prevent its taken to prevent disturbance of the soil being moving upward during the push of the sampling tube.

sampled and to prevent upward movement of soil Care should be taken to ensure that the sample is not into the casing, Washing with open-ended pipe for disturbed during its removal from the borehole or in cleaning or advancing sample borcholes should not disassembling the sampler. References 2 and 3 be permitted. Bottom-discharge bits should be used provide descriptions of suitable proccedures for ob- only with low-to-medium fluid pressure and with taining undisturbed samples.

upward-deflected jets.

With the conscientious use of proper field tech- The groundwater or drilling mud level should be niques, undisturbed samples in normally con- measured at the -start and end of each work day for solidated clays and silts can usually be recovered by borings in progress, at the completion of drilling, and means of fixed-piston-type thin-wall tube samplers at least 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after drilling is completed, In addi- without serious difficulty. Recovery of good un- tion to pertinent information normally recorded, all disturbed samples in sands requires greater care than depths and amounts of water or drilling mud losses, in clays, but with proper care and attention to detail, together with depths at which circulation is they can also be obtained with fixed-piston-type thin- recovered, should be recorded and reported on bor- wall tube samplers in most sands that are free of ing logs and on geological cross sections. Logs and bouiders and gravel size particles. Appendix B lists a sections should also reflect incidents of settling or number of sampling methods that are suitable for use dropping of drill rods, abnormally low resistance to in these and other materials.

drilling or advance of samplers, core losses, in- stability or heave of the side and bottom of Undisturbed samples of boulders, gravels, or sand- borcholes, influx of groundwater, and any other gravel mixtures generally are difficult to obtain, and special feature or occurrence. Details of information often it is necessary to use hand sampling methods in that should be presented on logs of subsurface in- test pits, shafts, or other accessible excavations to get vestigations are given in regulatory position 2. good samples.

Depths should be measured to the nearest tenth of When obtaining undisturbed samples of granular a foot and be correlatable to the elevation datum soils below the groundwater table, dewatering by used for the site. Elevations of points in the borehole means of well points or other suitable methods may

1.132-6

he required. Osterberg and Varaksin (Ref. 4) describe

C. REGULATORY POSITION

a sampling program using dewatering of a shaft in sand with a frozen surrounding annulus. Samples rhe site investigations program needed to deter- suitable for density determination, though not for mine foundation conditions at a nuclear po%ker plant tests of mnichanical properties. may sometimes be ob- site is highly dependent on actual site conditions. The tained I'roi* boreholes with the help of chemical program should he flexible and adjusted as the site in- stabilization or impregnation (Refs. 5. 6). Special vestigation proceeds with the advice of experienced prcautions are required when toxic chemicals are personnel familiar with ti, site. The staff will revie\%

used. Also. where aquifers are involved, it may not be the results of each site investigation program on a advisable to injeit chemicals or grouts into them. case-by-case basis and make an independent evaluv,- Useful discussions of methods of sampling granular tion of foundation conditions in order to judge the soils are given by l-vorslev (Ref. 7) and Barton adequacy of the information presented.

(Rer. 8).

1. General Site Iniestigation Site investigations for nuclear power plants Si.ould

7. Handling. Field Storage, and Transporting of Sam- be adequaite. in terms of thoroughness. suit:*bility of ples the methods used. quality of execution o ' the work.

and documentation. to permit an accurate determina- Treatoiient of samples after their recovery from the tion of the geologic and geotechnical conditions that ground is as critica0l to their quality as the procedures affect the design. performance, and safe(ty of the used in obtaining them. Samples of cohesionless soils plant. The investigations should provide information are particularly sensitive to disturbance in handling needed to assess foundation conditions at the site ::nd and require extreme care during removal from the to perform engineering analysis and design with borehole, removal from the sampler. and subsequent reasonable assurance that foundation conditions handling in order to prevent disturbance from impact have been realistically estimated.

and vibration (Ref. 2). Special precautions are re- quired in transporting undisturbed samples because Information to be developed should, as ap- of their sensitivity to vibration and impact. They propriate. include (I) topographic. hydrologic.

should be kept in a vertical position at all times. hydrographic, and geologic maps: (2) plot plans.

should be well padded to isolate them from vibration showing locations of major structures and explora- and impacts. and should be transported with extreme tions: (3) boring logs and logs of trenches and excava- care. Transportation by commercial carriers is not tions: and (4) geologic profiles showing excavation advisable. Block samples should be handled by limits for structures and geophysical data such as methods that give them equivalent protection from time-distance plots. profiles, and inhole surveys.

disturbance. All undisturbed samples should be Positions of all boreholes. piezometers. observation properly sealed and protected against moisture loss. wells. soundings. trenches, exploration pits. and geophysical investigations should be surveyed in both Disturbed samples* may be sealed in the same way plan and elevation and should be shown on plot as undisturbed samples. if in tubes. or may be placed plans. geologic sections, and maps. All surveys in suitably marked, noncorroding. airtight con- should be related to a fixed datum. The above infor- tainers. Large representative samples may be placed mation should be in sufficient detail and be in- in plastic bags, in tightly woven cloth, or in noncor- tegrated to develop an overall view of the project and roding cans or other vessels that do not permit loss of the geologic and geotechnical conditions affecting it.

fine particles by sifting. Such samples may be trans- ported by any convenient means.

2. Logs of Subsurface Imestigations Rock cores need to be stored and transported in durable boxes provided with suitable dividers to pre- Boring logs should contain the date when the bor- vent shifting of the cores in any direction. They ing was made. the location of the boring with should be clearly labeled to identify the site, the bor- reference to the coordinate system used for the site.

ing number, the core interval, and the top and hot- the depths of borings, and the elevations with respect tom depths of the core. If the box has a removable *to a permanent bench mark.

lid, labeling should be placed on both the outside and inside of the box, as well as on the lid. Special con- The logs should also include the elevations or the tainers may be required to protect samples to be used top and bottom of borings and the level at which the for fluid content determinations and shale samples to water table and the boundaries of soil or rock strata be used for tests of mechanical properties from were encountered, the classification and description changes in fluid content. Core samples should be of the soil and rock layers, blow count values ob- transported with the care necessary to avoid breakage tained from Standard Penetration Tests, percent or disturbance. recovery of rock core, and Rock Quality Designation

1.132-7

I-

(RQD). Results of field permeability *tests and changes in materials. Alternating splitspoon and un- borehole logging should also be included on logs. The disturbed samples with depth is recommended.

type of tools used in making the boring should be recorded. It' the tools were changed, the depth at For granular soils, samples should be taken at which the change was made and the reason for the depth intervals no greater than 5 feet. Beyond a depth change should be noted. Notes should be provided of of 50 feet below foundation level, the depth interval everything significant to the interpretation of subsur- for sampling may be increased to 10 feet. Also it is face conditions, such as lost drilling fluid, rod drops, recommended tital onw or more borings for each ma- and changes in drilling rate. Incomplete or aban- jor structure be contiuously sampled. The borirg doned borings should be described with the same care should be reamed and cleaned between samples. Re- as successfully completed borings. Logs of trenches quirements fe" undisturbed sampling of granular and exploratory excavations should be presented in a soils will depend on actual site conditions and re- format similar to the boring logs. The location of all quirements for laboratory testing. Some general explorations should be shown on the geologic section 6 guidelines for recovering undisturbed samples are together with elevations and important data. given in Section B.4.b(2) and Section B.6 of the dis- cussion of this guide. Experimentation with different

3. Procedures for Subsurface lnvestigations sampling techniques may be n,:cessary to determine the method best suited to local soil conditions.

Some techniques widely used for subsurface in- vestigations are listed in Appendix B. It also cites ap- propriate standards and references procedures from For compressible or normally consolidated clays.

published literaturelwith general guidelines on the ap- undisturbed samples should be continuous plicability, limitations, and potential pitfalls in their throughout the compressible strata in one or more use. Additional suitable techniques are provided by principal borings for each major structure. These other literature listed in Appendix D. The use or in- samples should be obtained by means of suitable vestigations and sampling techniques other than fixed-piston-type thin-wall tube samplers or by those indicated in this guide is acceptable when it can methods that yield samples of equivalent quality.

be shown that the alternative methods yield satisfac- tory results. The attainment of satisfactory results in Borings used for undisturbed sampling of soils driiling, sampling, and testing is dependent on the should be at least 3 inches in diameter. Criteria for techniques used, on care in details of operations, and obtaining undisturbed tube samples include the fol- on timely recognition of and correction of potential lowing:

sources of error. Field operations should be super- vised by experienced professional personnel at the a. Tubes should meet the specifications of

.site of operations, and systematic standards of prac- ASTM Standard D 1587-67 (Ref. 9):

tice should be followed. Procedures and equipment b. The Area Ratio* of the sampler should not used to carry out the field operations should be documented, as should all conditions encountered in exceed 13 percent and preferably should not exceed all phases of investigations. Experienced personnel 10 percent:

thoroughly familiar with sampling and testing procedures should also inspect and document sampl- c. The Specific Recovery Ratio* should be ing results and transfer samples from the field to between 90 and 100 percent: tubes with less recovery storage or laboratory facilities. may be acceptable if it appears that the sample may have just broken off and otherwise appears essential-

4. Spacing and Depth of Subsurface Investigations ly undisturbed:

Criteria for the spacing and depth of subsurface ex- d. The Inside Clearance Ratio* should be the ploration at locations or safety-related structures for minimum required for complete sample recovery, favorable or uniform gcologic conditions are given in Appendix C. The application of these criteria is dis- e. Samples recovered should contain no visible cussed in Section B.4 of this guide, The investigative distortion of strata or opening or softening or effort required for a nuclear power plant should be materials brought about by the sampling procedure.

greatest at the locations of Category I structures and may vary in intensity and scope in other areas ac- 6. Retention of Samples, Rock Core, and Records cording to their spatial and geolgical relations to the site. Samples and rock cores from principal borings should be retained at least until the power plant is

5. Sampling licensed to operate and all matters relating to the in- terpretation of subsurface conditions at the site have Sampling of soils should include, as a minimum, been resolved. The need to retain samples and core the recovery of samples at regular intervals and at beyond this time is a matter of judgment and should

1.132-8 II

he evaluated on a case-by-casetimebasis.andSoilwillsamples in not be

D. IMPLEMENTATION

This guide will be used by the staff to evaluate the tubes will deteriorate with

0 suitable for any undisturbed testing. However, they may be used as a visual record of what the foundation material is like. Similarly, core or rock subject to results of site investigations, including the adequacy and quality of data provided to define foundation conditions and the geotechnical parameters needed slaking and rapid weathering such as shale will also for engineering analysis and design. submitted in con- deteriorate. It is recommended that photographs of nection with construction permit applications scil samples and rock core togedher with field and docketed after June 1. 1978. The staff will also use final logs of all borings and record samples with this guide to evaluate the results of any new site in- material descriptions be preserved for a permanent vestigations performed after June 1, 1978. by a record. Other important records of the subsurface in- person whose construction permit was issued on or vestigations program should also be preserved. before June 1. 1978.

b

1.132-9

APPENDIX A

DEFINITIONS

For the convenience of the user, the following Piezoineter-adevice or instrument for measuring terms are presented with their definitions as used in pore pressure or hydraulic potential at a level or this guide: point below the ground surface.

Principalborings-those exploratory holes that are Accessible exca'ation-anexcavation made for the used as the primary source of subsurface informa- purpose of investigating and sampling materials or tion. They are used to explore and sample all soil or conditions below the ground surface, of such shape and dimensions as to permit the entry of personnel rock strata wi~hin the interval penetrated to define the geology of the site and to determine the properties for direct examination, testing, or sampling. of the subsurface materials. Not included are borings Area Ratio- (Ca) of a sampling device is defined from which no samples are taken, borings used to in- as: vestigate specific or limited intervals, or borings so close to others that the information yielded repre- D: -13 sents essentially a single location.

a De Representative sample-a sample that (1) contains approximately the same mineral constituents of the where Do is the outside diameter of that part of the stratum from which it is taken, in the same propor- sampling device that is forced into the soil, and De is tions, and with the same grain-size distribution and the inside diameter, normally the diameter of the cut- (2) is uncontaminated by foreign materials or ting edge. chemical alteration.

Rock Quality Designation (RQD)-an indirect Boring-ian exploratory hole in soil or rock, or both, made by removal of materials in the form of measurement of the degree of rock fracturing and samples or cuttings (cf. soundings). jointing and rock quality. It is calculated by summing the lengths of all hard and sound pieces of recovered Disturbedsample-a sarpple whose internal struc- core longer than 4 inches (10cm) and dividing the ture has been altered to such a degree that it does not sum by the total length of core run.

reasonably approximate that of the material in situ. Sounding-an exploratory penetration below the Such a sample may be completely remolded, or it ground surface by means of a device that is used to may bear a resemblance to an undisturbed sample in measure or observe some in situ property of the having preserved the gross shape given it by a sampl- materials penetrated. usually without recovery of ing device. samples or cuttings.

Geoteclmical-of or pertaining to the earth sciences Specific Recovery Ratio-(R.) in the advance of a (geology, soils, seismology, and groundwater sample tube is defined as:

hydrology) and that part of civil engineering which Rs=

deals with the interrelationship between the geologic environment and the works of man. where AL is the increment of length of sample in the In situ test-a test performed on in-place soil or tube corresponding to an increment AH of sampler rock for the purpose of determining some physical advance.

property. As used in this guide, it includes Soil structure-a complex physical-mechanical geophysical measurements. property, defined by the sizes, shapes, and arrange- ments of the constituent grains and intergranular Inside Clearance Ratio (Ci) of a sampling device is matter and the bonding and capillary forces acting defined as: among the constituents.

Supplementary borings or supplementary DiDe- De soundings-boringsor soundings that are made in ad- i

dition to principal borings for some specific or where Di is the inside diameter of the sample tube or limited purpose.

liner and D. is the diameter .of the cutting edge. Undisturbed sample-a sample obtained and treated in such a way that disturbance of its.original Observation well-an open boring that permits structure is minimal, making it suitable for measuring the level or elevation of the groundwater laboratory testing of material properties that depend table. on structure.

1.132-10

APPENDIX B

METHODS OF SUBSURFACE EXPLORATION'

METHOD PROCEDURE APPLI CA BI LITY LIMITATIONS

METHODS OF ACCESS FOR SAMPLING, TEST. OR OBSERVATION

Pits, Trenches, Excavation made by hand, Visual observation, photo- Depth of unprotected excava- Shafts, Tunnels large auger, or digging graphy, disturbed and un- tions is limited by ground- machinery. (Ref. 7) disturbed sampling, in sitt. water or safety considerations.

testing of soil and rock.

Auger Boring Boring advanced by hand Recovery of remolded samples, Will not penetrate boulders or auger or power auger. and determining groundwater most rock.

(Ref. 7) levels. Access for undisturbed sampling of cohesive soils.

Hollow Stem Auger Boring advanced by means Access for undisturbed or Should not be used with plug in

7-= Boring of continuous-flight helix representative sampling granular soils. Not suitable auger with hollow center through hollow stem with for undisturbed sampling in stem. (Ref. 10) thin-wall tube sampler, loose sand or silt. (Ref. I1)

core barrel, or split- barrel sampler.

Wash Boring Boring advanced by Cleaning out and advancing Suitable for use with sampling chopping with light hole in soil between sample operations in soil only if done bit and by jetting intervals. with low water velocities and with upward-deflected with upward-deflected jet.

jet. (Ref. 7)

Rotary Drilling Boring advanced by ro- Cleaning out and advanc- Drilling mud should be used in tating drilling bit; ing hole in soil or rock granular soils. Bottom discharge cuttings removed by between sample intervals. bits are not suitable for use with circulating drilling undisturbed sampling in soils un- fluid. (Ref. 7) less combined with protruding core barrel, as in Denison -.ampler, or with upward-deflected jets.

Scc also Rers. 32-40.

APPENDIX B (Continued)

METHODS OF SUBSURFACE EXPLORATION

METHOD PROCEDURE APPLICABILITY LIMITATIONS

METHODS OF ACCESS FOR SAMPLING, TEST, OR OBSERVATION

Percussion Boring advanced by Detection of voids and Not suitable for use in soils.

Drilling air-operated impact zones of weakness in hammer. rock by changes in drill rate or resistance. Access for in situ testing or logging.

Cable Drilling Boring advanced by Advancing hole in soil Causes severe disturbance in soils- repeated dropping of or rock. Access for not suitable for use with undis- I~

heavy bit: removal sampling, in situ testing, turbed sampling methods.

of cuttings by bailing. or logging in rock. Pene- (Ref. 7) tration of hard layers, gravel, or boulders in auger borings.

Continuous Boring advanced by Recovery of representative Effects of advance and withdrawal Sampling or repeated pushing of samples of cohesive soils of sampler result in disturbed Displacement sampler or closed and undisturbed samples in sections at top and bottom of Boring sampler is pushed some cohesive soils. sample. In some soils, entire to desired depth, and sample may be disturbed. Best sample is taken. (Ref. 7) suited for use in cohesive soils. Continuous sampling in cohesionless soils may be made by successive reaming and cleaning of hole between sampling.

METHODS OF SAMPLING SOIL AND ROCK'

Hand-Cut Block Sample is cut by Highest quality undisturbed Requires accessible excavation or Cylindrical hand from soil ex- samples in all soils and dewatering if below water Sample posed in excavation. and in soft rock. table, Extreme care is required (Refs. 12, 13) in sampling cohesionless soils.

s. Requires

15) experienced operator.

Thin-walled tube is Undisturbed samples in Frequently ineffective in Pitcher Sampler hard, brittle, cohesive cohesionless soils.

pushed into soil by spring above sampler soils and sands with while outer core bit cementation. Representa- reams hole. Cuttings tive samples in soft to removed by circulating medium cohesive soils and drilling fluid. (Ref. 13) silts. Disturbed samples may be obtained in cohesion- less materials with variable success.

0

APPENDIX B (Continued)

METHODS OF SUBSURFACE EXPLORATION

METHOD PROCEDURE APPLICABILITY LIMITATIONS

METHODS OF SAMPLING SOIL AND ROCK

Denison Sampler Hole is advanced and Undisturbed samples in Not suitable for undisturbed reamed by core drill stiff to hard cohesive sampling in loose cohesionless while sample is re- soil, sands with cemen- soils or soft cohesive soils.

tained in nonrotating tation. and soft rocks.

inner core barrel with Disturbed samples may corecatcher. Cuttings be obtained in cohesion- removed by circulating less materials with drilling fluid. variable success.

(Refs. 12. 13)

Split-Barrel Split-barrel tube is Representative samples Samples are disturbed and not or Splitspoon driven into soil by in soils other than suitable for tests of physical g', Sampler blows of falling ram. coarse granular soils. properties.

Sampling is carried out in conjunction with Standard Pene- tration Test. (Ref. 9)

Auger Sampling Auger drill used to Determine boundaries Samples not suitable for physical advance hole is with- of soil layers and properties or density tests.

drawn at intervals for obtain samples Large errors in locating strata recovery of soil samples for soil classification. boundaries may occur without close from auger flights. attention to details of procedure.

(Ref. 9) (Ref. 13) In some soils, particle breakdown by auger or sorting effects may result in errors in determining gradation.

APPENDIX B (Continued)

METHODS OF SUBSURFACE EXPLORATION

METHOD PROCEDURE APPLICABILITY LIMITATIONS

METHODS OF SAMPLING SOIL AND ROCK

Rotary Core Hole is advanced by core Core samples in compe- Because recovery is poorest in Barrel bit while core sample is tent rock and hard soils zones of weakness, samples gener- retained within core with single-tube core ally fail to yield positive infor- barrel or within station- barrel. Core samples in mation on soft seams, joints. o:'

ary inner tube. Cuttings poor or broken rock may other defects in rock.

removed by circulating be obtainable with double- drilling fluid. tube core barrel with (Ref. 9) bottom-discharge bit.

Shot Core Boring advanced by ro- Large diameter cores and Cannot be used in drilling at Boring tating single core accessit'- boreholes in large angles to the vertical.

(Calyx) barrel, which cuts by rock. Often ineffective in securing

0% grinding with chilled small diameter cores.

steel shot fed with circulating wash water.

Used shot and coarser cuttings are deposited in an annular cup, or calyx, above the core barrel.

(Ref. 7)

Oriented Reinforcing rod is Core samples in rock Samples are not well suited to Integral grouted into small- with preservation of tests of physical properties.

Sampling diameter hole, then joints and other zones overcored to obtain of weakness.

an annular core sample. (Ref. 16)

Wash Sampling Cuttings are recovered Samples useful in con- Sample quality is not adequate or Cuttings from wash water or junction with other for site investigations Sampling drilling fluid. data for identification for nuclear facilities.

of major strata.

APPENDIX B (Continued)

METHODS OF SUBSURFACE EXPLORATION

METHOD PROCEDURE APPLICABILITY LIMITATIONS

METHODS OF SAMPLING SOIL AND ROCK

Subm ersible Core tube is driven Continuous representa- Because of high area ratio and Vibratory into soil by vibrator. tive samples in uncon- effects of vibration, samples may (Vibracore) (Ref. 17) solidated marine sedi- be disturbed.

Sampler ments.

Underwater Core tube attached to Representative samples Samples may be seriously Piston Corer drop weight is driven in unconsolidated marine disturbed. (Ref. 19)

into soil by gravity sediments.

after a controlled height of free fall.

Cable-supported piston remains in contact with soil surface during drive.

(Ref. 18)

Gravity Corer Open core tube attached Representative samples No control of specific recover%

-.1, to drop weight is driven at shallow depth in ratio. Samples are disturbed.

into soil by gravity after unconsolidated marine free fall. (Ref. IN) sediments.

METHODS OF IN SITU TESTING OF SOIL AND ROCK

Standard Split-barrel sampler is Blow count may be used as FExtremelv unreliable in silts, Penetration driven into soil by blows an index of consistency or silty sands, or soils containing Test of falling weight. Blow density of soil. May be gravel. In sands below water count for each 6 in. used for detection of table, positive head must be main- of penetration is recorded. changes in consistency tained in borehole. Determination (Ref. 9) or relative density in of relative density in sands clay or sands. a be requires site-specific correlation used with empirical or highly conservative use of relationships to estimate published correlations. Results relative density of clean are sensitive to details of sand. apparatus and procedure.

APPENDIX B (Continued)

METHODS OF SUBSURFACE EXPLORATION

METHOD PROCEDURE A PPL.ICA BIILITY LIMITATIONS

METHODS OF IN SITU TESTING OF SOI

l. AND ROCK

Steel cone is pushed Detection of changes in Strength estimates require onsite Dutch Cone verification by other methods of Penetrometer into soil and followed consistency or relative by subsequent advance density in clays or sands. testing.

of friction sleeve. Used to estimate static Resistance is measured undrained shear strength during both phases of of clay. Used with empiri- advance. (Ref. 20), cal relationships to obtain estimate of static compres- sibility of sand.

co Field Vane Four-bladed vane is Used to estimate in situ Not suitable for use in silt, sand.

Shear Test pushed into undisturbed undrained shear strength or soils containing appreciable soil. then rotated to and sensitivity of clays. amounts of gravel or shells. May cause shear failure on yield unconservative estimates of cylindrical surface. shear strength in fissured clay Torsional resistance soils or where strength is strain- versus angular deflec- rate dependent.

tion is recorded. (Ref. 9)

Drive-Point Expendable steel cone is Detection of gross changes Provides no quantitative infor- Penetrometer driven into soil by blows in consistency or relative mation on soil properties.

of falling weight. Blow density. May be used in count versus penetration some coarse granular soils.

is recorded. (Ref. 13)

Plate Bearing Steel loading plate is Estimation of strength and Results can be extrapolated to Test (Soil) placed on horizontal moduli of soil. May be used loaded areas larger than bearing surface and is stati- at ground surface, in excava- plate only if properties of soil cally loaded, usually by tions, or in boreholes. are uniform laterally and with hydraulic jack. Settle- depth.

ment versus time is recorded for each load increment. (Ref. 9)

0 0

rn~_

APPE 'B (Continued)

METHODS OF SUBSURFACE EXPLORATION

PROCEDURE APPLICABILITY LIMITATIONS

METHOD

METHODS OF IN SITU TESTING OF SOIL AND ROCK

Plate Bearing Bearing pad on rock Estimation of elastic moduli Results can be extrapolated to Test or Plate surface is statically of rock masses. May be used loaded areas larger than bearing Jacking Test loaded by hydraulic at ground surface, in exca- pad only if rock properties are (Rock) jack. Deflection vations, in tunnels, or in uniform over volume of interest versus load is recorded. borcholes. and if diameter of bearing pad (Ref. 21) is larger than average spacing of joints or other discontinuities.

Pressure Meter Uniform radial pressure Estimation of elastic moduli Test results represent properties Test (Dilatometer is applied hydraulically of rocks and estimation of only of materials in near vicinity Test) over a length of borehole shear strengths and compress- of borehole. Results may be mis- several times its diame- ibility of soils by empirical leading in testing materials ter. Change in diameter relationships. whose properties may be

7- versus pressure is recorded. anisotropic.

(Ref. 21)

Field Pumping Water is pumped from or Estimation of in situ permea- Apparent permeability may be Test into aquifer at constant bility of soils and rock mass. greatly influenced by local rate through penetrating features. Effective permeability well. Change in piezo- of rock is dependent primarily metric level is measured on frequency and distribution at well and at one or more ofjoints. Test result in rock is observation wells. Pumping representative only to extent that pressures and flow rates are segment penetrated by borehole.

recorded. (Refs. 22. 23) is representative of joint system of rock mass.

Direct Shear Block of in situ rock is Measurement of shearing Tests are costly. Usually Test isolated to permit shearing resistance of rock mass in variability of rock mass requires along a preselected sur- situ. a sufficient number of tests to face. Normal and shearing provide statistical control.

loads are applied by jacking.

Loads and displacements are recorded. (Ref. 24)

APPENDIX B (Continued)

METHODS OF SUBSURFACE EXPLORATION

METHOD PROCEDURE APPICA BI LITY L.IMITATIONS

METHODS OF IN SITU TESTING OF SOIL AND ROCK

Determination of elastic Volume of rock tested is dependent Pressure Tunnel Hydraulic pressure is on tunnel diameter. Cracking due Test applied to sealed-off constants of the rock mass in situ. to tensile hoop stresses may length of circular affect apparent stiffness of rock.

tunnel, and diametral deformations are measured.

(Ref. 21)

Same as pressure tunnel test. Same as pressure tunnel test.

Radial Jacking Radial pressure is applied

0 Test to a length of circular tunnel by flat jacks. Dia- metral deformations are measured.

Determination of elastic Apparent stiffness may be affected Borehole Jack Load is applied to wall of by development of tension cracks.

Test modulus of rock in situ.

borehole by two diametric- ally opposed jacks. Deform- Capable of applying greater ations and pressures are pressures than dilatome- ters.

recorded. (Ref. 25)

Borehole Device for measurement of Measurement of absolute Stress field is affected by Deformation Meter diameters (deformation stresses in situ. borehole. Analysis subject to meter) is placed in bore- limitations of elastic theory.

hole, and hole is overcored Two boreholes at different orien- to relieve stresses on tations are required for determi- annular rock core contain- nation of complete stress field.

ing deformation meter. Questionable results in rocks Diameters (usually 3) are with strongly time-dependent measured before and after properties.

overcoring. Modulus of rock is measured by laboratory tests on core; stresses are computed by elastic theory. (Ref, 26)

APPENDIX B (Continued)

METHODS OF SUBSURFACE EXPLORATION

METHOD PROCEDURE APPLICABILITY LIMITATIONS

METHODS OF IN SITU TESTING OF SOIL AND ROCK

Inclusion Rigid stress indicating Measurement of absolute Same as above.

Stressmeter device (stressmeter) is stresses in situ. Does placed in borehole, and not require accurate knowl- hole is overcored to edge of rock modulus.

relieve stresses on annu- lar core containing stress- meter. In situ stresses are computed by elastic theory. (Ref. 26)

Borehole Strain Strain gauge is cemented Measurement of absolute Same as above.

Gauge to bottom (end) of bore- stresses in situ. Requires hole. and gauge is over- only one core drill size.

cored to relieve stresses on core containing strain IL-) gauge. Stresses are computed from resulting strains and from modulus obtained by laboratory tests on core.

(Ref. 26)

Flat Jack Test Slot is drilled in rock Measurement of one corn po- Stress field is affected by surface producing stress nent of normal stress in excavation or tunnel. Interpre- relief in adjacent rock. situ. Does not require tation of test results subject Flat jack is grouted into knowledge of rock modulus. to assumption that loading and slot and hydraulically unloading moduli are equal.

pressurized. Pressure Questionable results in rock required to reverse with strongly time-dependent deformations produced by pruperties.

stress relief is observed.

(Refs. 26. 27)

APPENDIX B (Continued)

METHODS OF SUBSURFACE EXPLORATION

METHOD PROCEDURE APPLICABILITY LIMITATIONS

METHODS OF IN SITU TESTING OF SOIL AND ROCK

Hydraulic Fluid is pumped into scaled- Estimation of minor principal Affected by anisotropy of tensile Fracturing Test off portion of borehole stress. strength of rock.

with pressure increasing until fracture occurs.

(Ref. 26)

Crosshole Seismic signal is trans- In situ measurement of com- Requires deviation survey of Seismic Test mitted from source in pression wave velocity and boreholes to eliminate errors one borehole to receiv- shear wave velocity in soils due to deviation of holes from er(s) in other bore- and rocks. vertical. Refraction of signal hole(s), and transit through adjacent high-velocity time is recorded. (Ref. 28) beds must be considered in interpretation.

Uphole/Downhole Seismic signal is In situ measurement of com- Apparent velocity obtained is SeismicTest transmitted between pression wave velocity and time-average for all strata borehole and ground shear wave velocity in soils between source and receiver.

surface, and transit and rocks.

time is recorded. (Ref. 28)

Acoustic Velocity Logging tool contains Measurement of compression Results represent only the Log transmitting transducer wave velocity. Used primar- material immediately adjacent and two receiving trans- ily in rocks to Obtain to the borehole. Can be obtained ducers separated by fixed estimate of porosity. only in uncased, fluid-filled gage length. Signal is borehole. Use is limited to transmitted through rock materials with P-wave velority adjacent to borehole and greater than that of borehole transit time over the fluid.

gage length is recorded as difference in arrival times at the receivers.

(Refs. 29. 30)

0

APPENDIX B (Continued)

METHODS OF SUBSURFACE EXPLORATION

METHOD PROCEDURE A PPIJCABSILITY ILIMITATIONS

METHODS OF IN SITU TESTING OF SOIL AND ROCK

3-D Velocity Logging tool contains Measurement of compression Results represent only the transmitting transducer wave and shear wave velocity material immediately adjacent Log to the borehole. Can be obtained and receiving transducer ties in rock. Detection of separated by fixed gage void spaces. open fractures, only in uncased, Iluid-filled length. Signal is trans- and zones of weakness. borehole. Correction required mitted through rock for variation in hole size. Use adjacent to borehole. and is limited to materials with P-

wave train at receiver wave velocity greater than that is recorded. (Ref. 31) of borehole fluid.

Apparent electrical resis- Appropriate combinations of Can be obtained only in uncased Electrical tivity of soil or rock in resistivity logs can be used borcholes. Hole must be fluid Resistivity neighborhood of borehole to estimate porosity and degree filled, or electrodes must be Log is measured by in-hole of water saturation in rocks. pressed against wall of hole.

logging tool containing In soils, may be used as Apparent resistivity values are one of a wide variety of qualitative indication of strongly affected by changes in electrode configurations. changes in void ratio or hole diameter, strata thickness, t-J water content, for correla- resistivity contrast between adja- (Refs. 29. 30)

tion ofstrata between cent strata. resistivity of boreholes, and for location drilling fluid, etc.

of strata boundaries.

Neutrons are emitted into Correlation of strata Because of very strong borehole Neutron Log effects, results are generally rock or soil around bore- between boreholes and hole by a neutron source location of strata not of sufficient accuracy for in the logging tool, and boundaries. Provides an quantitative engineering uses.

a detector isolated from approximation to water the source responds to content and can be run in either slow neutrons or cased or uncased, fluid- secondary gamma rays. filled or empty boreholes, Response of detector is recorded. (Refs. 29. 30)

APPENDIX B (Continued)

METHODS OF SUBSURFACE EXPLORATION

METHOD PROCEDURE APPLICA BILITY IEMITATIONS

METHODS OF IN SITU TESTING OF SOIL AND ROCK

Gamma rays are emitted Estimation of bulk density Effects of borehole size and Gamma-Gamma Log in rocks, qualitative indi- density of drilling fluid must

("Density Log") into rock around the borehole by a source in cation of changes in densi- be accounted for. Presently the logging tool, and a ty of soils. May be run in not suitable for qualitative detector isolated from empty or fluid-Filled holes. estimate of density in soils the source responds to other than those of -rock-like"

back-scattered gamma character. Cannot be used in rays. Response of de- cased boreholes, tector is recorded.

(Ref. 29)

Film-type or television Detection and mapping of Results are affected by any

4'"

Borehole joints, seams, cavities, or condition that affects visi- Cameras camera in a suitable protective container other visually observable bility.

is used for observation features in rock. Can be of walls of borehole. used in empty, uncased holes (Ref. 32) or in holes filled with clear water.

APPENDIX C

SPACING AND DEPTH OF SUBSURFACE EXPLORATIONS FOR SAFETY-RELATED' FOUNDATIONS

TYPE OF STRUCTURE SPACING OF BORINGS' OR SOUNDINGS MINIMUM DEPTH OF PENETRATION

General For favorable, uniform geologic conditions, where The depth of borings should be determined on the basis continuity of subsurface strata is found. spacing should of the type of structure and geologic conditions. All be as indicated for the type of structure with at least one borings should be extended to a depth sufficient to boring at the location of every safety-related or Seismic define the site geology and to sample all materials that Category I structure. Where variable conditions are may swell during excavation, may consolidate found, spacing should be smaller, as needed, to obtain a subsequent to construction, may be unstable under clear picture of soil or rock properties and their earthquake loading, or whose physical properties would variability. Where cavities or other discontinuities of affect foundation behavior or stability. Where soils are engineering significance may occur, the normal very thick, the maximum required depth for engineering exploratory work should be supplemented by borings or purposes, denoted dmax, may be taken as the depth at soundings at a spacing small enough to detect such which the change in the vertical stress during or after features. construction for the combined foundation loading is less than 10% of the in situ effective overburden stress. It may also be taken as the depth at which the shear wave velocity of the soil mass exceeds 3.000 ft/sec. It may be necessary to include in the investigation program several borings needed to complete information to establish the tb.j soil model for soil-structure interaction studies. These borings may be required to penetrate depths greater than those depths required for general ený;inecring purposes. Borings should be deep enough to define and evaluate the potential for deep soil stability problems at the site. Generally all borings should extend at least 30

feet below the lowest part of the foundation. If competent rock is encountered at lesser depths than those given, borings should penetrate to the greatest depth where discontinuities or zones of weakness can affect foundations and should penetrate at least 20 ft into sound rock. For weathered shale or soft rock.

depths should be as for soils.

'As dctcrmincd by Itt'jt1 ocaiiivns of .,ife .-relted structure.- and facififics.

lii

'Includc. shafts or other accessible excvations that meet depth requirements.

APPENDIX C

SPACING AND DEPTH OF SUBSURFACE EXPLORATIONS FOR SAFETY-RELATED 3 FOUNDATIONS

TYPE OF STRUCTURE SPACING OF BORINGS4 OR SOUNDINGS MINIMUM DEPTH OF PENETRATION

Structures including Principal borings: at least one boring beneath every Principal borings: at least one-fourth of the principal buildings, retaining walls. safety-related structure. For larger, heavier structures, borings anid a minimum of one boring per structure to concrete dams. such as the containment and auxiliary buildings, at least penetrate into sound rock or to a depth equal to dmax.

one boring per 10,000 sq ft (approximately 100 ft Others to a de;th below foundation elevation equal to spacing) and, in addition, a number of borings along the the width of structure or to a depth equal to the periphery, at corners, and other selected locations. One foundation depth below the original ground surface.

boring per 100 linear ft for essentially linear structures.? whichever is greater.'

0% Earth dams, dikes, levees, Principal borings: one per 100 linear ft along axis of Principal borings: one per 200 linear ft to dmax. Others and embankments. structure and at critical locations perpendicular to the should penetrate all strata whose strength would affect axis to establish geological sections and groundwater stability. For water-impounding structures, to sufficient conditions for analysis.' depth to define all aquifers and zones of underseepage that could affect performance of structure.-

Deep cuts, 6 canals Principal borings: one per 200 linear ft along the Principal borings: one per 200 linear ft to penetrate into alignment and at critical locations perpendicular to the sound rock or to dmax. Others to a depth below the alignment to establish geologic sections for analysis.! bottom elevation of"cavation equal to the depth of cut or to below, the lowest potential failure zone of the slope.! Borings should penetrate pervious strata below which groundwater may influence stability.

AIso supplementary borings or soundings which are design dependent or nccessary to define anomalies. critical abutment conditions. etc.

Includes temporary cuts, open during construction. where loss of strength due to excessive deformations would affect ultimate site safety.

0

_____ - -- ____

APPENDIX C

SPACING AND DEPTH OF SUBSURFACE EXPLORATIONS FOR SAFETY-RELATED3 FOUNDATIONS

TYPE OF STRUCTURE SPACING OF BORIN(;S 4 OR SOUNDINGS MINiNMUM DEPTH OF PENETRATION

Pipelines Principal borings: This may vary depending on how well Principal borings: For buried pipelines, one per 200

site conditions are understood from other plant site linear ft to penetrate into sound rock or to dmax. Others borings. For variable conditions, one per 100 linear ft to 5 times the pipe diameters below the invert elevation.

for buried pipelines: at least one boring for each footing For pipelines above ground. depths as for foundation for pipelines above ground.' structures.

Tunnels Principal borings: one per 100 linear ft.' Principal borings: one per 200 linear ft to penetrate into sound rock or to diiax. Others to 5 times the tunnel diameter below the invert elevation,'

1.-j

-j Reservoirs, impoundments Principal borings: one per 50,000 ft' of interior area of Principal borings: at least one-fourth. but no fewer than the impoundment. in addition to borings at the one, of the principal borings to penetrate into sound locations of dams or dikes.' rock or to dmax. Others to a depth of 25 ft below rc.esrvoir bottom elevation.'

, Stippkllcn~iery horing, o~r%on ingai nce'%JrY to define zin-naliics.

APPENDIX D

REFERENCES

1. U.S. Army Corps of Engineers, Instrumentation 12, U.S. Dept. of Interior, Bureau of Reclamation, of Earth and Rock-Fill Dams (Groundwater and Pore Earth Manual, Ist ed.. Denver, Colorado, 1960, pp.

Pressure Observations), Engineer Manual EM 1 110-2- 346-379.

1908. 1972. 13. Terziaghi. K.. and R. B. Peck. Soil Alechlnics in Engineering Practice. 2nd ed., John Wiley and

2. U.S. Army Corps of Engineers, Soil Sampling. Sons, Inc., New York. 1963. pp. 299-300.308-314.

Engineer Manual EM 1110-2-1907. 1972, Ch. 3, 4. 322-324.

3. U.S. Navy, Design Manual, Soil Mechanics, 14. Osterberg. J. 0., "New Piston Type Soil Founidations, andl Earth Structures. A',-1 VF,,l C DM-7. Sampler.'* Engineering Newiv-Record 148. 1952, pp.

Dept. of the Navy, Naval Facilities Engineering 77-78.

Command. Alexandria. Virginia, 1971. 15. Kjellman, W.. T. Kallstanins, and 0. Wager.

"Soil Sampler with Metal F",<,,- Royal Swedish

4. Osterberg, J.O., and S. Varaksin, "Determina- Geotechnical Institute. Proceeding No. I.

tion of Relative Density of Sand Below Groundwater Stockholm. Sweden. 1950.

Table.~ Evaluation of Relative Densit' and Its Role in Geotechnical Projects inrowiving Cohesiohless Soils.

American Society for Testing and Materials. 16. Rocha. M., "A Method of Obtaining Integral Philadelphia. STP 523. 1973, pp. 364-376. Samples of Rock Masses," Association of Engineer- ing Geologists. Bulletin* 10(I). 1973. pp. 77-82,

5. Karol. R. H.. "Use of Chemical Grouts to Sam- pie Sands,~ Sampling of Soil adl Rock, American 17. Tirez. G. B.. "Recent Trends in Underwater Society for Testing and Materials, Philadelphia, STP Soil Sampling Methods." Underwater Soil Samtpling.

483, 19*71. pp. 51-59. Testing. and Construction Control. American Society for Testing and Materials. Philadelphia. STP 501.

6. Windisch. S. J.. and M. Soulie. "Technique for 1972. pp. 42-54.

Study of Granular Materials." J. Soil Mlech. Found.

Dir.. American Society of Civil Engineers. V. 96 18. Nooranz. I., "Underwater Soil Sampling and (SM4). 1970, pp. 1113:1126. Testing-A State-of-the-Art Review." Underwater Soil Sampling. Testing, and Construction Control.

7. Hvorslev. IM. J.. Subsurface Exploration and American Society for Testing and Materials, Sampling o0Soils .lr Civil Engineering PurposeS. U.S. Philadelphia. STP 501, 1972. pp. 3-41.

Army Waterways Experiment Station, Vicksburg, Mississippi. 1949. pp, 51-71.83-139, 156-157. 19. McCoy, F. W., Jr., "An Analysis of Piston Coring Through Corehead Camera Photography',"

8. Barton. C. MI.. "Borehole Sampling of Underwater Soil Sampling. Testing. and Construction Saturated Uncemented Sands and Grouts," Control. American Society for Testing and Materials.

Groundwater 12(3). 1974. pp. 170-181. Philadelphia, STP 501, 1972. pp.90-105.

20. Schmertmann. J. H., "Suggested Method for

9, American Society for Testing and Materials, Deep Static-Core Penetration Test." Special

1974 .I ntunl Book of' ,.ISTAI S.S'wlftr ls' Port' 19. l'roc&'durt's fi)r Testilng Soil anil Rock otr ligitlcr'irhg Philadelphia. 1974, pp. 192,194. 206-207, 224-229. Purposes, American Society for Testing a11d

261.263, 317-320. Materials, Philadelphia. STI1 479, 1970. pp. 71-77, IL stio K, (1,, "111 8i4t1 " (m

1 the I ck uo*rings,' Special proC'lhires),or T'sfing sait (o41 Sons, Inc,, Now York, Ch. 5, 1968K pp. 126-144, Rock' or EngiineeringPurposes. American Society for Testing and Materials, Philadelphia, STP 479, 1969, 22. Cedergrvn, H, R., Seepage. Drainage,and Flow Ii. Peck. R. B.. W. E. Hanson, and T. 11,Thorn- D3. Sead'im, 3. L.. "Inflone~c of"hnestim tl'l. \Viler burn. Foundation Engineering. John Wiley and Sons, on the Behavior of Rock Masses." Rock Mechanics in Inc.. New York, 2nd ed.. 1974. pp. 105-106. Engineering Practice. K. G. Stagg and 0. C.

(

132-28

1

ZienkiewicL, eds., John Wiley and Sons, Inc., New nerit of Soil Properties. Proceedings of the Specialty York, 1968, Ch. 3. Conference of the Geotechnical Engineering Divi- sion. American Society of Civil Engineers. Raleigh,

24, D)odds, R. K., "Suggested Method of Test for North Carolina, 1975, pp. 121-150.

In Situ Shear Strength of Rock." Special lProcedures

.lr Testing Soil wdl Rock jor Engineering Purposes.

American Society for Testing and Materials,

29. Schlumberger Ltd.. Log Interpretations. Vol.

I (Principles), Schlumberger. Ltd., New York. 1972.

Philadelphia, STP 479. 1970, pp. 618-628.

Ch. 3-9.

25. Goodman. R. E.. T. K. Van, and P. E. Henze.

"Measurement of Rock Deformability in Bore- 30. Haun, J. D., and L. W. Leroy. editors, Subsur- holes.** Proceedings ofthe Tenth Symposiumn on Rock face Geology in Petroleum Exploration. A. Sjionposiwt.

Mlechanics, A.fustin, Texas. 1968. pp. 523-555. Colorado School of Mines. Golden. Colorado, Ch.

14. 15, 21. 1958.

26. Roberts. A.. "The Measurement of Strain and Stress in Rock Masses,'" Rock Mechanics in Engineer- 31. Gever, R. L. and J. I Myung. "The 3-D

I ing Practice. K. G. Stagg and 0. C. Zienkiewicz. eds., Velocity Log: a Tool for In Situ Determination of the John Wile), and Sons. Inc., New York, 1968, pp. 166- Elastic Moduli of Rocks." Proceedingsofthe Tweljih

191, 194. Symposi.111on Rock AMechanics. Rolla/. Missouri.

27. Rocha. M., "New Techniques in Delor- 1971, pp.71-107.

mability Testing or In Situ Rock Masses," Deter- inination of the in Situ Atodiduvs of Deformation of 32. Lundgren. R., F. C. Sturges. and L. S. Cluff.

Rock, American Society for Testing and Materials, "General Guide for Use of Borehole Cameras-A

Philadelphia. STP 477, 1970. Guide." Special Proceduresfor Testing Soil anil Rock for Engineering Purpose

s. American Society for

28. Ballard. R. F., Jr. and F. G. McLean, "Seismic Testing and Materials, Philadelphia. STP 479. 1970.

Field Methods for In Situ Moduli," in Situ Measure- pp. 56-61.

1.132-29

APPENDIX E

BIBLIOGRAPHY

Bates. E. R.. "I)Deection of Subsurface Cavities." Osterberg, .1. 0.. "An Improved Ilydraulic Piston MI iscellaneous Paper. S-73-40. U.S. A rm \Vaterways Sampler." Proceedings olf the Eihth /Inerlariona al I-xperiment Station. Vicksburg. NIississippi. 1973. COnh'rrence on Soil Aflechanics aniid Fotundatlion h'ngin'erinr, Mloscow. LUSSR, Vol. 1.2. 1973. pp. 317-

321.

Calhoon. NI. [.. "'Pressurc-.Mctcr Field Tcsting of Soils." Civil E'ntgine'ring 39(7), 1969. pp. 71-74. Sh1a.nllnon. Wilson. Inc., and Agbahian-.lacobsen Associates, "'Soil Behavior Under IEarthquake l.oading Conrditions: State-of-tle-A rt -valuatil tof"

(;hIssop. R.. "-The Rise of Geotechnology and Its Soil Characteristics fur Seismic Response An:iy.sis.'

Inillnence on I-neineering Practice.'" Ieihtlh Rankine U.S. .\I:C Report. 1972.

Leclure: Gvcechnique 1iI,2), 1968. pp. 105-150.

Task Committee for Foundation D)esign Manual.

Hlall. W. J.. N. M. Newmark. and A. J. Hendron. "'SUbsurface In\Vest6iation for I)esiun and Construc- ion of' Foundations of Buildi ngs.'" .. 1oilAlech.

.Jr.. "Classification. Elngineering Properties and Field Fo"und. lv.. A\merican Society of Civil I-ngincers.

Exploratioll of Soils, Intact Rock. and In Situ Mas-

1972. V. 98(SM5): pp. 481-490. V.98(SN16: pp. 557- s.es.'" US. AEC Report WASH-130). 1974.

578. V. 98(SNI!7): pp. 749-764. V. 9,(SNIX): pp. 771-

785.

iMisterek. 1). L., "'Analysis of Dlata from Radial Jack in Tests.-" /)eet'rmiaiiog tlf the In Sint .Mthldult Wallace. G. 11.. I. .1. Slehir. and 1. :A. Anderson.

of I)Ml10rmnlclion of Rock. American Societv Ifor -Radial Jacking Test for Arch Dams." !'roceedings Testing and MIate-,ials. Plhiladelphia. STI' 477. 1970. of Mie 1*'0ih S/.rmtp.iti on R j( A .I*chi'mic.. .k.Aut11in.

pp, 27-38. 1968. pp. 633-660.

0

1.132-30

Regulatory Guide 1.132: Difference between revisions

Revision as of 10:17, 4 November 2019

Contents

A. INTRODUCTION

C. REGULATORY POSITION

D. IMPLEMENTATION

s. Requires

l. AND ROCK

s. American Society for

Navigation menu

Regulatory Guide 1.132: Difference between revisions

Revision as of 10:17, 4 November 2019

A. INTRODUCTION

C. REGULATORY POSITION

D. IMPLEMENTATION

s. Requires

l. AND ROCK

s. American Society for

Navigation menu

Search