Loading...
HomeMy WebLinkAbout; 1000 Chinquapin Apt Complex; Soils Report; 1974-02-26ALYARADO SOILS ENGINEERING - WlUAM t. CATUN 7830 LA MESA BOULEVARD TelrPHONE Cir,, Enpi”... LA MESA, CALIFORNIA 92041 4bl-3000 February 26, 1974 SOILS INVESTIGATION ?roposed 44 Unit Apartment Complex 1000 Chinquatin Avenue West of Harrison Street Carlsbad, California For SWYS Corporation Project No. 14A5B Phillip H. Gustafson Civi: and Structural Engineer ALVARADO SOILS ENGINEERING WILLIAM 0. CATUN ,830 LA MEIA m”LE”ARD TELEPHONE Cl”,, En*in..: LA MESA. CALIFORN,* 91041 461.1000 Soils Investigation Introduction This is to present the findings and conclusions of a soils investigation conducted at the site of a proposed 44 Unit Apartment Complex for SWYS Corporation, located at 1000 Chinquatin Avenue, West of Harrison Street, in the City of Carlsbad, State of California. This parcel is more spe- cifically described as being a portion of Tract 237 and Northerly half of Chinquatin Avenue of Thum Lands according to Map No. 1681 thereof, in the City of Carlsbad, County of San Uiego, State of California. It is understood that the development will consist of 3 buildings, 2 stories in height, over parking faciiities. The structures will be of wood frame and masonry construction. The objectives of the investigation were to determine the existing soil con- ditions and physical properties of the soils so that engineering reconunenda- tions could be presented for the safe and economical grading of the site and design of foundations for the proposed structures. In order to acconlplish these objectives, 3 pits were excavated, undisturbed and loose bag samples were obtained, and laboratory tests were performed on these samples. Page 2 Project No. 14A5B SWYS Corporation 2/25/74 r. FIELD INVESTIGATION Three pits were excavated with a tractor-mounted backhoe at the approximate locations shown on the attached Drawing No. 1, entitled "Location of Ex- ploration Pits". The pits were excavated to depths of 6.5 feet to 8.0 feet below the existing ground surface. A continuous log of the soils en- countered in the pits was recorded at the time of digging and is shown in detail on Drawing Kos. 2 to 4, inclusive, each entitled "Summary Sheet". .- The soils were visually and texturally classified by the field identifi- cation procedures set forth on rhe Unified Soil Classification Chart. Un- disturbed chunk and drive samples were obtained at frequent intervals in the soils ahead of the excavation. The drop weight used for driving the sampling tube into the soils weighed 50 pounds, and the average drop was 30 inches. The general procedures used in field sampling are described briefly under "Sampling" in Appendix B. LABORATORY TESTS Laboratory tests were performed on representative samples in order to de- termine.the dry density and moisture content. The results of these tests are presented on Drawing Nos. 2 to 3, inclusive. Compaction tests were performed on representative samples of the soils.to be excavated to establish compaction criteria. The soils were tested ac- cording to the A.S.T.M. D1557 70 method of compaction which uses 25 blows of a 10 pound rammer falling 18 inches on each of 5 layers in a 4 inch diameter l/30 cubic foot meld. The results of these tests are presented on the following page: Page 3 Project No. 14A5B SWYS Corporation 2/25/74 Depth Maximum Optimum Moisture Pit Sarrlpl e of Sample Dry Density Content % No. No. in Feet Soil Description lb/cu.ft. Dry Wt. 1 1 1.0 Tan silty fine to 123.0 11.6 medium sand 2 2 6.5 Light tan silty fine 121.7 11.9 to Imedium sand Direct shear tests were performed on saturated and drained samples in order to determine the minimuin angle of internal friction and apparent cohesion of Pit 1, Bag l* Depth 1.0 Pit 2, Bag ?* Depth 6.5 : 1.04 1.71 31.5 4 2.91 Pit 1, Sasiple 1 1.29 Depth 4.0 : 2.21 4 3.81 Pit 3, Chunk 1 : 1.16 Depth 2.5 2.50 4 4.08 * :: Remolded to 90 percent of maximum dry density. 41 400 41 400 Angie of Normal Shearing Internal Load in Resistance Friction kips/sq.ft. kips/sq.ft. Degrees 0.99 1.85 37 3.12 the soils. The results of these tests are presented below: Apparent Cohesion lb/sq.ft. 250 500 Cortisolidation tests were performed on representative samples in order to determine the load-settlement characteristics of the soils. The results of the tests are presented on Drawing Nos. 5 and 6, entitled "Consolidation Curves". Page 4 Project No. 14A5B SWYS Coiporation 2/25/74 The general procedures used ~for the preceding laboratory tests are described briefly in Appendix B. General DISCUSSiON, CONCLUSIONS AND RECOMMENDATIONS The ger?eral topography of the site may be described as relatively level. Vegetation consisted of light brush and several trees. According to the "Soil Map" of San Diego County prepared by the U.S. Department of Agri- culture, the upper soils in the area consisted of somewhat excessively drained to moderately well drained loamy coarse sands and fine sandy loams that have a subsoil of sandy clay over a hardpan. The inajor soil type en- countered in this investigation consisted of loose to medium dense silty sand which became increasingly dense at relatively shallow depths of 1.5 to 4.0 feet. Conclusions 1. The Imedium dense to dense natural soils encountered in ail pit locations are suitable for use as siipportlng material for the proposed structures and/or fills. 2. All of the soils may be satisfactorily compacted in fill areas to support th? proposed loads. 3. None of the soils enccuntered on the site were considered to be sgffi- ciently expansive with respect to change in volume with change in moisture content to warrant special design of foundation and slabs. -. Page 5 Project No. 14A5B SWYS Coi,poration 2/25/74 4. Both cutting and filling may be required for the development of the site. Structures may be constructed partly in cut and partly in fill provided the load-settlement characteristics of the natural soil and compacted filled ground are comparable. 5. If any soil types are encountered during grading operations that were not tested in the investigation, additional laboratory tests will be conducted in order to determine their physical characteristics and supplemental reports and recommenddtiOns will automatically become a part of the specifications. Recommendatiors 1. The medium dense to dense natural soils have a safe bearing value for supporting dead load on1.y of 3,000 pounds per square foot for continuous or square footings, one foot in minimum horizontal dimension, and placed at a depth of at least 12 inches below the surface of the medium dense to dense undisturbed natural yround. For supporting dead plus live loads, footings constructed as set forth above may be safely loaded to as much as 3,500 pounds per square foot. The settlement of such footings, so placed and loaded to 3,000 pounds per square foot, is estimated to be on the order of l/8 inch. These bearing values for natural soils may be increased 400 pounds per sqcare foot for each additional foot of depth and 100 pounds per square foot for each additional foot of width to a maximum of 3,500 pounds per square foot for dead loads only and 4,000 pounds per square foot for dead plus live loads. 2. All of the soils may L:e satisfactorily compacted in fill areas and when properly colllpacted to at least 90 percent of maximum dry density, have a safe bearing value for supporting dead load only of 2,300 pounds per square Page 6 Project No. 62ClF SWYS Corporation 2125174 foot for continuous or square footings, one foot in minimum horizontal dimension and placed at a depth of at least 12 inches below the final compacted ground surface. For supporting dead plus live loads, footings constructed as set Forth above may be safely loaded to as much as 2,800 pounds per square foot. The settlement of such footings, properly embedded in filled ground and loaded to 2,300 pounds per square foot, is estimated to be less than l/8 inch. Recommendations for the place- ment of filled ground are presented in the attached Appendix A, entitled "Recommended Earthwork Specifications". These bearing values for filled ground may bc increased 300 pounds per square foot for each additional foot of depth and 100 pounds per square foot for each additional foot of width, to a Imaximum of 3,000 pounds per square foot for dead load only and 3,500 pounds per square foot ~for dead plus live loads. All of the above bearing values may be further increased by l/3 for combined dead, live, and seismic or wind loading. finy upper loose, disturbed natural soils similar to those encountered in Pit No. 1 to a depth of 1.5 feet that remain below finish grade should be removed and be uniformly recompacted to at least 90 percent of maximum dry density in order to provide adequate support to proposed filled ground and structures. 3. In calculating the resistance of the soil to lateral movement, an allowable passive earth pressure of 500 pounds per square foot may be used at a depth of one foot below the lowest adjacent ground surface, and this may be increased at the rate of 150 pounds per square foot for -~ each additional foot of depth. A friction value of 0.4 times the dead load between concrete and soil may also be used. Page 7 Project No. 62CIF SWYS Corporation 2725174 - 4. For the design of all retaining walls less than 15 feet in height with level backfill, an active earth pressure equivalent to a fluid pressure of 30 pounds per cubic foot [may be used, and if the walls are restrained at their upper ends, an additional 50 pounds per square foot of pressure against the wall should be used in design. Especial care should be exer- cised during construction to prevent excessive pressure from being exerted against these walls from any compaction equipment that ~may be used in backfilling. The active earth pressure does not include any hydrostatic pressure and all retaining walls should be protected against any seepage and accumulation of surface waters behind them Drawing Nos. 1 to 6, inclusive, and Appendices A and B are parts of this report. Reviewed William G. Catlin, RCE 11579 (2) bgl SWYS Corporation 2g30 Westwood Boulevard Los Angeles, California 90064 Attn: Mr. Jim Welker, Construction Supervisor City of Carlsbad Btiildiny Inspection 1200 Elm Avenue Carlsbad, California Attn: Mr. Ray Green W 3 5 : z a < s Z : L, , -- r- L-l\ i3 ,---TREE j L’ I P-l LEGAL A PORTiON OF 7-RA-7. L ,‘- . UOR TH E R L Y ri A L F 0 i .,.. . :aII,,sjP;N Ai/Et-JjE ,‘7F -;,I,, ,~Atq 33 ACLORDII\IL- 7-’ ,‘>“.t.- NO. 1681, IN i-t?E ~,T’I L. iA-<ti BAD >T,.T% e’s7 .A,,. ,a LEGEND LOCATION OF EXPLORATION PiT C iO:AT.dN OF Eh?,JX \r.’ PRCJpO56.D 44 SiNIT ir:‘.qR: COl%\FLEX F3K. SW)3 ,>KWRATlC’N I 0 0 0 L t-! / p\; ,:1 ,J ,4 I- i N A , ,z : CAKL?BAD - i,A _I F-JKfij ,i PROJELr h;c ,.J /15 y, swu i iOiLS EtGINEERING SUMMARY SHEET ELEVATlOll _ Tan, damp, loose v - Indicates in-situ density test 0 - Indicates loose bag sample Indicates undisturbed drive sample Indicates undisturbed chunk sample SUMMARY SHEET PIT NO. 2 ELEVATION ?ed tan, damp, loose -- --- Medium dense .ight tan, damp, very lense Silty fine to medium sand , 19 :t’ : . : ,q ;z $4 - 5.3 1 > I i3: i I g: c ‘2: L - 23. c ‘,z 2 u ‘r >c, ;: !?E z: - 77. PROJ EC1 NO. ALVARADO ENGINEERING DRAWING NO SUMMARY SHEET PIT NO.3- 3.7 112.6 123.0 l- .: : . : ., ., ::;' .: : ,I :' .' : ,: ,': ,:::I ::. --- Dark brown, damp, dense 8.1 114.5123.c9: 3 :: .; ;:Y“ ., .:..: ..,...: ,: :’ --..- ___ .~;'~~'~~~ Tan, damp, very dense .:.:: ,. . 4- . . : :' : ., ; : ., :, '.' : ., : : ,: : ,. .' : '; ,: 1~ ..: f,. : : ; 5- ., .'. ., .;. : ,' ,"... ; ; :: ,. : :. ,. : ::.:.. .:.,. ., ,. : .'. '., :, :: :..: ,: 6 : j ':: 'j : i: ,.: ; .,. ~,. . . ?- .y,: : !'. ,',J.' :, : j., ,, '1 : :' ; ,, : :...:, .".. __ % --~ PRO;JEt$ NO. I ALVARADO SOILS I ENGINEERING DRAW14(G N CONSOLIDATION CL’RVES Load in Kips per Square Foot , ;Ll\ or I o( (,+ 1.0 2 4 6 ;;;;* 16 DFPTH 1.0 I.!~ t -L-we-T w I l’~~~l./Illll I 2 I I I I IIIII I I I Ill/ Xl I I///II I 1 I I 1 I 1 -4. I I I I II I I A - t t-l-H-- -l I PullI nl~.-tt-tStf-.--- T - 1 _I _I IL, I I I 2 Tl I /III/// I I I -IlRlI -i z 5 IL t- I I I / I I I I , I, 5 -----l I I I I I I I I PIT 1 0 Indicates Percent Consolidation at Field Moisture l Indicates Percent Consolidation after Saturation Project No. ALVARADO SOILS ENGINEERING Drawing No. 14A5B 5 CONSOLIDATION CURVES Load in Kips per Square Foot 0 Indicates Percent Cotlsolidation at Field Moisture 0 Indicates Percent Corlsolidation after Saturation ‘reject No. 14A5B ALVARADO SOILS ENGINEERING Drawing No. 6 ALVARADO’ SOILS ENGINEERING APPENDIX A RECOMMENDED EARTHW'lR~~PECIFICATIONS 1. Generdl Description The objective is to obtain uniformity and adequate -- internal strength in filled ground by proven engineering procedures and tests so that the propos,'tl structures may be safely supported. The pro- cedures include the clearing and grubbing, removal of existing structures, preparation of land to be filled, processing the fill soils, filling of the land, the spreading, and colllpdction of the filled areas to conform with the lines, grades and slopes as shown on the approved plans. The owner shall retain a Civil Engineer qualified in Soil Mechanics (herein referred to as Engineer) to inspect and test the filled ground as placed to verify the uniformity of compaction of filled ground to the specified 90 percent of maximum dry density. The Engineer shall advise the owner and grading contractor, immedi,ltely if any unsatisfactory conditions are observed to exist and shall h<Jve the authority to reject the compacted filled ground until such time that corrective measures are taken, necessary to cali~ply with the specifications. It shall be the sole responsibility - of the grading contractor to achieve the specified degree of compaction. 2. Clearing, Grubbing, atld PreEr&!p/'reas to be Filled (a) (b) (cl Cd) All brush, vegetation and any biodegradable refuse shall be removed, piled and burned or otherwise disposed of so as to leave the areas to be filled free of vecjctation and debris. Any uncompacted filled ground shall be removed unless the report recommends otherwise. Ahy ullstable, soft, t.wampy, or otherwise unsuitable areas shall be corrected by draining or rc:moval, or both. The natlit-al ground whit h is determined to be satisfactory for the support of the fi'lled !irouni> shall then be plowed or scarified to a depth ol' at least six inches (6"), and until the surface is free from ruts, hummocks, or other uneven features which would tend to prevent uniform compaction by the equipment to be used. After the natural ground has beer1 prepared, it shall then be brought to the proper moisture cotltent ilnd colllpacted to not less than 90 percent of maximum tlcnsity in ‘lccorddtlce with A.S.T.M. D1557-70 method which uses 25 blows of a 10 l'ound rammer falling 18 inches on each of 5 layers in a 4 inch diameter l/30 cubic foot cylindrical mold. Where fills are mclde on hillsides or exposed slope areas, with gradients greater than 10 percent, horizontal benches shall be cut into firm undisturbed natural ground in order to provide both lateral and vertical Page 2 I'.KOIII~ENUIU EAKTHWOKK SPECIt iCATIONS (CONT.) stability. Tllis is to provide a horlzonLa1 base so that each layer is placed and compal.ted on J horizon,al plane. The initial bench at the toe of the f;ll shall be at l.:ast 10 feet in width on firm undisturbed natural ground st the elevation of the toe stake placed ,at the natural angli of reijose or d&sign slope. ~The Engineer shall determine the width ind frequency of all succeeding benches which will vary with the : Ii1 conditions <lnd the steepness of slope. 2. Materials arid Special Reg\lirel, ,nts. The fill soils shall consist of select .-,- materials free from veget,.ble [[latter, and other deleterious substances, and shall not contain rocks ot lumps greater than 6 inches in diameter. This may be obtained from the excavation of tlanks, borrow pits or any other approved sources and by mixing soils ft-In one or more sources. If excessive vegetation, rocks, or soils with inddcqu,~te strength or other unacceptable physical characteristics <Il~e enc,,untered, these shall be disposed of in waste areas as shown on tl:.? plans or as directed by the Engineer. If, during grading operations, :~,oils Ire fuund which were not encountered and tested in the prelin,inary investi!,Jtion, tests on these soils shall be performed to determine -heir physical characteristics. Any special treatment recom- mended in the preliminary c, subsequent soil reports not covered herein shall become an addc:ndum to these specifications. The testing and specifications for the compaction of subgrade, subbase, and base materials for roads, streets highways, or other public property or rights-of-way shall be in accordance with the standards of the governmental agency having jurisdiction. 4. Placing, Spreading, and Compactiilpl ill Jaterials. (a) When the moisture content of the fill material is below that specified by the Enyineer, water sha!l be added in the borrow pit until the moisture content is near optimum to assure uniform mixing and effective compaction. (b) When the moistrrt.2 contetlt of ,he fill rmaterial is above that specified by the Engineer, resulting in inadequate compaction or unstable fill, the fill material shall be aerated by blading and scarifying or other satisfactory mrthuds until the moisture content is near optimum as specified. (c) After processing, the suitable fill material shall be placed in layers which, when con,pacted, shall I\ot exceed six inches (6"). Each layer shall be spread evenly and shall be thoroughly mixed during the spreading to insure uniformity of material and moisture in each layer. (d) After each layer has been placed, mixed and spread evenly, it shall be thorou$lly compacted to not less than the density set forth in paragraph ,' (c) <lbove. Compaction shall be accomplished with sheeps- foot rollers, multiple-wheel pneumatic-tired rollers, or other approved types of compaction equipni?nt, such as vibratory equipment that is specially designed for certain soil types. Rollers shall be Page 3 RECOMMENt!ED EAR~iliWORK >PELIFICATIONS (C\lNT.) 5. 6. 7. -, 8. of such design a11ti maintained to such a level that they will be able to compact the fill materinl to the spe,.ified density. Tamping feet of sheepLfoot roller:; shall be rmiintain~d such that the soil will be compacted rather that1 sheared by the roller. Rolling shall be accomp- 'lished while the fill material is at the specified moisture content. Rolling of each layer shall be continuous over its entire area and the roller shall make sufficient trips to insure that the specified density has been obtained. Roll~ing shall be accomplished in a planned procedure sL(ch that the entire areas to be filled shall receive uniform compactive effort. (e) The surfaces of the fill slopes shall be compacted by means of sheeps- foot rollers or otlIzr suitable equipment. Compacting operations shall be continued until the slopes dre stable and until there is no appreciable amount of loose soil on the slopes. Compacting of the slopes shall be accomplished by backrolling the slopes in increments of 3 to 5 feet in elevation gain or by other methods producing satisfactory results. (f) Field density tests shall be take11 for approximately each foot in ele- vation gain after compaction, but not to exceed two feet in vertical height between tests. F'ield density tests may be taken at intervals of 6 inches in elevation gain if required by the Engineer. The location of the tests in plan shall be so spaced to give the best possible cover- age and shall be taken no farther apart than 100 feet. Tests shall be taken on corner and terrace lots for each two feet in elevation gain. The Engineer may take additional tests as considered necessary to check on the uniformity of compaction. Where sheepsfoot rollers are used, the tests shall be taken in the compacted material below the disturbed surface. NJ additional layers of fill shall be spread until the field density tests indicate that the specified density has been obtained. (g) The fill operation sha 1 bl continued in six inch (6") compacted layers as specified above, unil lile fill has been brought to the finished slopes and grades as s town \)n the accepted plans. ~;,;PKti+. Sufficient 'inspection by the Engineer shall be maintained during Tng and compacting operations so that he can verify that the fill was constructed in accordance with the accepted specifications. Seasonal Limits. No fill material shall be placed, spread, or rolled if weather conditions increase tire moisture content above permissible limits. When the work is interrupted by rain, fill operations shall not be resumed until field tests by the soils engineer indicate that the moisture content and density-of fill are as pt2viously specified. Limiting Values of Nonexpan<~lve Soils. Those soils that expand 3.0 percent or less from air dry to satL:ratlon undet~ a unit load of 150 pounds per square foot are considered to be nonexpansive. All recommendations prt,ent,:d in the attached report are a part of these specifications. ,- ALVARADO SOILS ENGINEERING .- WIUI.~M 0. CAWN 7830 LA MESA BO”LE”At!D TELEPHONE ClVil Engineer LA MESA, CALIwRNI* 91041 462-3000 APPENDIX2 Sampling (Undisturbed Drive Sample) The undisturbed drive samples are obtained by forcing a special sampling tube into the undisturbed ,soils at the bottom of the excavation. The sampling tube consists of a steel barrel, 3.0 inches outside diameter, with a special cutting tip and with a lining of twelve thin brass rings, each one inch long by 2.42 inches inside diameter. The sampler, connec- ted to a twelve inch long waste barrel, is either pushed or driven ap- proximately 18 inches into the soil and a six inch section of the center portion of the sample is taken for laboratory tests, the soil being still confined in the brass rings, after extraction from the sampler tube. The samples are taken to the laboratory in close fitting waterproof containers in order to retain the field moisture until completion of the test. The driving energy is calcuiated as the average energy in foot-kips required to force the sampling tube through 1 foot of soil at the depth at which the sample is obtained. Field Moisture and Density (Undisturbed Drive Sample) The field moisture and density are determined from undisturbed drive sam- ples by the following procedure. a. Carefully trimming the ends of the total sample (5 or 6 rings) such that the ends of the sample coincide with the plane of the ends of the rings. b. Weighing this trimmed sample, deducting the weight of the rings and dividing by the volume included within the rings, results in the wet density of the soil. C. Weighing a representative sample of the contents of 1 ring before and after drying to cietermine the moisture content. d. With the moisture content from (c) above and the wet density from (b) above, calculatitig the dry density of the soil sample. Sampling (Undisturbed Chunk Sample) An undisturbed chunk sample is a representative piece of the soil mass. The chunk is taken en masse from the stratum being investigated. It is then placed in a waterproof container to retain the field moisture and carefully transported to the laboratory. APPL~NDIX B -2- Field Moisture an< Density (Disturbed Sampling) The field moisture and density of the soil mass is determined by apply- ing the current applicable provisions of A.S.T.M. Test Method 01556. In particular, the sampling procedure consists of: a. Levelling the surface of the undisturbed in-place soil mass. b. Setting n special base plate approximately 12 inches square with a 6 l/2 inch diameter hole in the middle. C. Removing 5 to 8 pounds of soils through the hole in the base plate without disturbing the remaining soil mass. d. Determining the volume of the hole by filling it with a calibrated sand of known density through a special cone. The weight of sand is determined by the weight "lost" from a measured amount in filling the hole. e. Weighing the soil removed from the hole and thus determining the den- sity of the soil removed. f. Drying a sample of this removed ;oil in an oven to find the moisture content and thereby determining the dry density of the soil. Soil density relationship; for these purposes are based on the dry densi- ties. Field Moisture and Density (Undisturbed Chunk Sample) The field Imoisture and density are determined from undisturbed chunk sam- ples by the following procedure: a. Carefully trimming the sample to remove any loosely adhering soil. b. Inspecting the sample for evidence of disturbance such as cracks or voids that might occur around rock particles. C. Weighing the sample and meticulously coating it with wax. Especial care must be exercised in maintaining the proper wax temperature and dipping time to avoid partial wax saturation of the sample or air bubbles. d. Weighing the waxed sample in air and in water. From these weighings and the known density of paraffin, the volume of the wax, volume of the scil mass and the wet density of the soil mass is computed. e. Breaking up the sample to separate out any rock particles larger than 3/4 inch in nominal dimension. FPENDIX B -3- f. Drying a representative por.tion of the sample and weighing it before and after. From these results and the results of the steps above, the dry density of the soil mass (particles smaller than 3/4inch) is computed. Shear Tests_ The shear tests are run usiny a direct shear machine of the strain control type in which the rate of deformation is approximately 0.05 inch per min- ute. The machine is so designed that the tests are made without removing the samples from the brass liner rings in which they are secured. Each sample is sheared under a normal load equivalent to the weight of the soil above the p>,int of sampling. In some instances, samples are sheared under various normal loads in order to obtain the internal angle of friction and cohesion. Where considered necessary, samples are saturated and drained before shearing in order to simulate extreme field Imoisture conditions. Consolidation Tests - The apparatus used for the consolidation tests is designed to receive one of the one inch high rings of soil as it comes from the field. Loads are applied in several increments to the dpper surface of the test specimen and the resulting deformations are recorded at selected time intervals for each increment. Generally, each increment of load is maintained on the sample until the rate of deformation is equal to or less than l/10000 inch per hour. Porous stones are placed in contact with the top and bot- tom of each specimen to permit the ready addition or release of water. wnsion Te& Expansion tests are performed on air dried samples or on samples at opti- mum moisture content. In the first case, one inch high samples confined in the brass rings are permitted to air dry at 105" for at least 48 hours prior to placing into the expansion apparatus. The sample to be tested at optimum moisture is re,nolded to 90 percent of maximum dry density at optimum moisture content and placed directly on the expansion apparatus. A unit load of 150 pounds or 500 pounds per square foot is then applied to the upper porous stone in contact with the top of each sample. Water is permitted to contact both the top and bottom of each sample through porous stones. Continuous observations are made until upward movement is less than l/10000 inch per hour.