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Home My WebLink About; Carlsbad Villas; Soils Report; 1970-05-01- - - - - - SOILS INVESTIGATION crrtasbed JIII~S Ocean Strea t Carlsbad, California - - far Mr. Wet&II Butcher - - Project Na. 70-4-6A May 1, 1970 -i aENTON ENGINEERING. INC. - - c BENTON ENGINEERING, INC. *PPL,ED SOIL MECHANICS - FOUND*TIONs 6741 EL CAION BOULEVARD SAN DIICiO. CALIFORNIA *2115 SAY D,ICO: ?a3.,6,4 LA MI,.: 46%SBS. SOILS INVESTIGATION lntrcduction This is to present the resulk of a soils investigation conducted at the slh of the proposed Bayshore Inns Motel, plmmd for construction in the vicinity of 2687 Ocean Street, in Carlsbad, California. It is our urdeotanding fran a study prepared by Peter Ha&m 8, Associates, Eqineen and Consultank, that the proposed comtruction includes a 6 story motel appraxlmately 53 by 165 feet in overall plan and an adiacent parking and recreation structure - .- / \ four stories high and opproximahly 60 by 165 feet in overall plan. The structural loads are to be imposed chiefly by bearing vmlis, with maximum loads on the order of 12 to 25 klp per lineal feat and maximum colunn loads of 130 kips; the recreational and parkirg structure will - have same columrs. There is to be a swimmirq pool and an elrvatbr between the two buildings. The objectives of ihis Investigation wwre ta determine the existic\g roll conditions at the site of the proposed new construction, and to determine the maior physical properties of the on- - site soils, so that recommendations could be presented for the safe support of the buildings. In order to accomplish these abiectives, four barirq wre drilled, and undisturbed soil scm~ples - - _’ were obtained fran each of the borirqs for laboratory testing . Field Investigation All of the barirgs were drilled to a diameter of 24 inches with a truck-mounted rotary bucket-type drill rig at the approximate locotiom shown on the ottached Drawing No. 1, entitled “Location of Test Borings. ” The borirgs wre drilled to depths of 2 I to 41 feet below -2- the existiw ground surface. A continuous log of the soils encountered in the borings ~0s - - ,- - - - / - - ..- - i recorded at the time of drilling and is shown in detail on Drawiq Nos. 2 to 8, inclusive, each entitled “Summary Sheet.” The soils were visually classified by field identification procedures in accordance with the Unified Soil Classification Chart. A simplified description of this classification system is presented in the attached Appendix A at the end of this report. Undistirbed samples were obtained at frequent intervals in the soils ahead of the drilliq . The drop weight used for driviq the sanplilgl tube into the soils was the “Kelly” bar of the drill rig Which weighs 1623 pounds, and the average drop was 12 inches. The general procedures used in field sampling are described utier “Sompli~” in Appendix B. Laboratory Tests Lobomtory tests were performed on all undisturbed samples of Ihe soils in order to deter- mine the dry density, moisture content, and shearing strewth. The results of these tests are presented on Drawirq Nos. 2 to 8, inclusive. Consolidation tesk were performed on represent- ative samples in order ta dekrmine the load-settlement characteristics of the soils. The results of these tests are presented on Drawing Nos. 9 to 11, inclugive, each entitled “Consolidation Curves. ” The geneml procedures used for the laboratory tesk are described briefly in Appendix 8. DISCUSSION, CONCLLSIONS AND RECOMMENDATIONS Soil Strata Fine to medium sand ws found to a depth of 9 .O feet at Boring 1; these soils wre loose to a depth of 2.0 feet, medium compact between 2.0 and 5.0 feet, canpact between 5.0 and 6.5 feet, and then very canpoct. Fran 9.0 ta 9.8 feet wus a thin stmtum of very ccmpact gravelly fine to coarse sand, and then very firm slightly clayey fine to coarse sand was fourd LlEIIlON ENGINEERSNO. INC. - -3- to a depth of 18.0 feet. 8etwen 18.0 feet and the bottcm of the borirq at a depth of 36.0 - - c - - - feet ws a very firm clayey fine to medium sand that contained scattered grovel to 20.0 feet and below 29.0 feet. At Borirq 2 tine to medium sand was found to a depth of 6.0 feet; this stratum was loose to a depth of 1 .O foot, medium loose from 1 .O foot to 4.0 feet, and then medium can- pact. Fran 6.0 to 8.0 feet was a medium canpact gravelly fine ta medium sand or fine ta medium sandy gravel, and fram 8.0 feet to the bottom of the borim at a depth of 21 .O feet was a very firm slightly clayey fine to coarse sand. Fine to medium sand containirrg a slight clay binder above 6.8 feet was found to a depth of 20.0 feet at 8orig 3; these rolls wre medium capoct to a depth of 4.0 feet, com- pact betwwen 4.0 and 15.0 feet, and then very canpact. From 20.0 to 26.5 feet was a very cunpact fine to coarse sand that was gravelly below 25.5 feet, and then very firm clayey fine to coarse sand was found to the bottan of the boring at a depth of 41 .O feet. A slightly silty fine to medium sand was found to a depth of 11 .O feet at BoriG 4; these rolls were loose to medium firm to a depth of 2.0 feet, and then firm. At 11.0 feet of depth the soils merged to a canpoct fine to medium sand to a depth of 33.0 feet that contained 30 percent grovel and cobbles in the lowr 1.5 feet. From 33.0 feet to the bottom of the boriq at a depth of 34 .O feet WOI a very flrm clayey flm to medium sand. Ground water ws encountered below 8.5 feet at Borirrg 1, 6.0 feet at Borirq 2, 25.0 feetat Borirq 3 and 31.0 betat Boring 4. Conclusiore It is concluded frcm the ffeld investigation and the resulk of the laboratory testirg that the proposed motel building can be satisfactorily supported by continuous reinforced concrete foundations and the porkig structure can be supported by either contiruous wall footings or BENTON ENGINEERING. INC. - -4- isolated spread footiqs founded In the medium campact to campact soils found below relatively shallow depths at the various boring laca tlon. Recanmendations - - 1. Footig Design It is recommended that footlgs for the proposed bulldirqs be founded at least 6feet- - - below the existig ground surface and at Ieost 2 feet below the lowst adjacent ffnished grade on the medium ccmpact fine ta medium sand such as WQ found below the depths of 4.0 feet at Borlrgs 1 and 2, or on the mediun compact fine ta medium sand found below 3 feet at Boring 3, or on the firm slightly silty fine to medium sand found below 3 feet at Boriw~4. It is conclude fram an exunimtion of the “Study of A Motel for Mr. W. Butcher, Carlsbod,” prepared by Peter Harlem 6 Associates, that the foundations for the pcrklrrg garage will be placed on hai- zontal benches excavated more than 4 feet below the exlstirg hillside in the vicinity of Borings 3 and 4. lhe faotigs should be so placed that the slope between the bottom adjacent edges of any two footirgs is na steeper than a 1 l/“r horizontal to 1 vertical slope, and have at least 5 feet of horlrontol confinement. FooHtgs so located may be deslgned In accordance with the attached Drawing Nos. A and 8. In these drawings the solid lines indicate reccmmend- ed bearlrrg values far variars sizes of footlws at different depths as limited by the shear strengths of the soils, and the dashed lines indicate recammended bearim values as llmihd by estlmakd total settlemonk. All of the bearlg values shown on Drawirg Nos. A and B are for dead plus live loads only, and may be increased OM third for combined dead, live and seismic loads. 2. Swimming Pool and Elevator Shaft Structural support for the swimming pool and the elevata shaft may olso be provided by footirrgs deslgned in accordance with Drawim Nos. A and B. It is recommended that the swim- mlng pool and elevator shaft walls be designed ta resist lateral earth pressures equivalent to those - BENTON ENG4NEERING. #NC - -5- of a fluid having a unit Wight of 30 pounds per cubic foot above the water table and 90 pounds ( per cubic below the water level. - 3. Basement Wall Design. The design active pressure on the basement walls may be assumed to be 30 pounds Per cubic foot equivalent fluid pressure If backfilled with the sand type soils found on the site above - the water level. The allowable passive pressure below the lowest adjacent natural ground may be assumed ta be equal to an equivalent fluid pressure of 200 pounds per cubic foot. An allow- able friction factor of 0.4 times the applied dead load at the bme of footlrrg may be used. - -i - Respectfully submitted, BENTON ENGINEERING, INC. M. V. frothier, Civil Engineer Revled bG7 9, ,.~~~~~ iip . . n, - Distr: (2) Addressee (2) Peter A. Hatlem 8 Auaciates, Ergineen and Coroultank (2) Conrod Associates Attention: Mr. Ernie Soylord - - - - -L BENTON ENGINECRING. INC. -c .- - .- - - - - t, CONTINUOUS WALL SPREAD FOOTING DESIGN CURVES Continuous wall spread footims placed at least 4 feet below the existing ground surface at Boriws 1 ard 2 and at least 3 feet below the axistig ground surface at Barirqs 3 and 4 on recommended natural SC&. arig capacity as limited by soil shear strergth. a-- Width of Continuous Foatiq, Feet BAMHORE INNS MOTEL OCEAN STREET CARLSBAD, CALIFORNIA I. “O‘. I.-r- ..^ rm”Jlz‘cI l-a”. I I I DRAWING NO 7,?-4LA RFNTnN ENClNECDiNr- INr- I 7.0 -.- I I I I I L I I 5.0 4.0 3.0 2.0 SQUARE COLUMN SPREAD FOOTING DESIGN CURVES Isolated square footiws placed at least 4 feet below the exirtirg ground surface at Borings 1 and 2 and at least 3 feet below he exlsiitq ground surface at Boriqs 3 and 4 on recanmended natural soil. Bearirg capacity as limited by soil shear strergth 4 6 8 10 Width of Square Footitq, Feet BAYSHORE lNNS,MOTEL OCEAN STREET CARLSBAD, CALIFORNIA PROJECT NO. 70-4-bA I BENTON ENGINEERING, INC. I DRAWING NO. r4 - - - - - - - - - 8 hdbtes Apwox~mote Location of Test Boring BENTON ENGINEERtNGG, I~NC. SAN DIEGO, CALIFORNIA LOCATION OF TEST BORINGS - BAYSHORE /NNS MO7EL :C-EUVA?-/ON G?kZsBAD, c22UX+Vbl/IA - - r.J-’ &’ p-25’- 3-- I&’ 2 - -- - - MOTEL _ (PROPOSED ) 1 - - I +i=7a’ - PARK/NC SrR & TURE .- 52’ (PROPOSED 1) - - i EZEVAT/ON R~~RENCE POIN,‘:AS’(UMED EUVATIO fOO.00’ - - - - - - - - - - - - MOTE c PROPOSEL r - PARdc/N ( PROPO: 7 - - - - -1 .- - i -5 8 2 -= i?? -i - . m - - - i ‘;: - -: ? - SUMMARY SHEET BORING NO. 1 ELEVATION 70’ l 0 . .... -.:<<<:!:‘ri Gray, Slightly Moist, Loose, Gray with Dark Gmy ) FINE TO MEDIUM SAND Compact, Sane Shell Frogments ,:.‘.>,.+)r:‘: 50 b rate ( ,TJg$-- GRAVELLY FINE TO COARSE ravel to 2 Inches and Cobbles ; SAND I I I ,,&>q\ta 5 Inches _ +:fc: 13- .. ;;‘:.x . .:..:.;... >.*:;t:7 ‘.;i’ , 1;$ . .._.. I;.; +:y . . .. ;;‘:.x . 1 .:..:.;... . .*:;f:. . . . . . . y..r;F>? 1 . .i..Y..T{ . . . . ~~ $:jy:T y!;e.: y 1 .YyzZ.~ , :@; ‘... ;... :.: .-‘7.. . 1 ,:gi*. :...:...: SLIGHTLY CLAYEY FINE TO COARSE SAND Continued on Dm\ mir tg No. 2 5, :t: :r “cf EL 3 - I.4 8.1 9.7 i/I I! r 2 ! + 1, 1 I I/ I 9.0 ‘O.( 11.1 ll.C 21.4 11.5 23.3 I 1 t il: 1 ‘1 ! ( I 28.1,3.2 I I 83.4 0.32 ?0.9 0.55 82.6 03 ./ 22.8.2.61 - - - O- Irdicaies Undisturbed Drive Sample * - The elevatiom shown an tfiese Summary Sheets were obtained by level readings ta a reference elevation point shown on Drawing No. 1 with an assumed elevation of 100.0 feet. PROJECT NO, 70-4-6A BENTON ENGINEERING, INC. DRAWING NO. 2 - .- (~, ,~ - - - - 7 4 : _- -y c -, - - -. - - - - 18- 19- 20- 21- 221 23- 24- 25- 26- 27- 28- 29- 30- 31- 32- 33- 34- 3% 36 SUMMARY SHEET. BORING NO.-UCont.) . $\E~vn, Saturated, - Scattered Grwel to 1.5 Inches . - Between 18.5 and 20.0 Feet ---- jLIGHTLYCLAYE\r :I NE TO COARSE SAND Sane Scattered Gravel to 1 inch and Scattered Coarse . . . . . gg :LAYEY FINE TO vlEDlUM SAND 5, :!! 5:: “cl :t 1 -- 10.1 I9.C 13 .: $3 ’ -.c w). =3 z: -2: . - 9.5 10.6 2.4 2.7 - !2, !3, !O. 4.4; 5x2 3.84 5.37 - - - PROJECT NO. 70-4-M I BENTON DSAWING NO. ENGINEERING, INC. i 3 - -~ I” 1~ - .- - - .~ - I -,s ‘2 -$ 1 - - - - .- z Z$ SUMMARY SHEET rE &” 32 BORING NO.2 0 “2 ELEV .\TION 69.& Dark Gray, Saturated, Medium to Dark Gray, Saturated, Medium Compact, 60 to 70 Percent Grovel to 2 Inches, Cobbles , . Light Yellow-brown, Saturated, 1 Verv Firm FINE TO MEDIUM SAND ;RAVELLY FINE TO MEDIUM SAND / :INE TO MEDIUM SLIGHTLY CLAYE’ FINE TO COARSE SAND - 5 ;i 5: ,i >b L?i’ - 2.. 4.5 - - - 17.: ,8.7 2.c - : 1: 2: EC 3 - 2 4 - - - 12, IO, !O. - 91.: I.21 92 .; t.47 - - - - - - 19.’ ‘.5E 24.1 ‘.a9 25.1 - .62 - - - - - - - PROJECT NO 70-4-6A SNTON ENGINEERING, DRAWING NO. !Nf. 4 -, , - -- _1 - - .- .- - - - ,.- r SUMMARY SHEET s; &MC: 5 e’ ttf ti It; 2: et -3 t: 2: BORING NO.& t z !22* Ly - yl*=: g :$$j 2 Ly Y -- L”z ELEVATION 95.6' ;i -00 > vi 5;s sc( = s 0 l 0 zz rovm and Gray-brown, edium Canpact 3.2 9.3 106.6 0.40 4.9 8.6 108.4 0.92 Light Yellow-brown and Gray-brown, Moist, Compact 9.7 4.3105.1 1.25 FINE TO MEDIUM 8.1 3.0 96.5 1.45 .:::::.:.,: .:. ~,',.,.,., ,5-~~g~~~~~ Very Compact . . 16.2; 3.3 99.7 1.80 I 1 I I I BEN~tON ENGINEERING, DRAWING NO. INC. 5 _( - - - -. - - - ‘, . : - i 2 , -2 d - - - - - SUMMARY SHEET 5 . r 2:: rE u.c:Ei BOR,NG NO.ut.) z’>Pc;s2 Eti III 2 zzci z 5 gtzz 0 \ YlcyI YOP B. 2; I, Z’ pI * 2;s so’l ::‘j;i - Light Brownirh-groy, Slightly Moist, Very Compact 17.9 2.7 97.9 2.19 FINE TO COARSE SAND Light Brownishqray, Saturnted, GRAVELLY Very Compact 20 tu 30 Percent FINE TO COARSE Gravel to 2 Inches 38.3 16.4 113.4 2.94 Light Yellow-brown, Satumted, Very Firm PI\OJECT MI-2 I I ..m...,...^ .*.. 70-4-6A I l3EN TON ENGINEERING, INC. I - - - - - - -j \. I -< i --! d - -~ - - - SUMMARY SHEET BORING NO. 4 ELEVATION _L(Ila!iL :: j : ., 7 j; .; i ! :! 2 :; 1 I. I;? i. 1 : iLIGHTLY SILTY :INE TO MEDIUM SAND :INE TO MEDIUM SAND Continued on Drowiq F Jo.8 6 .! 4.5 8.’ 6.5 - 9.7 - 4.2 6.5 3.2 t z 5 a 5 - 05 as - a4 72 l.O( 1.6: - I .9i I .99 - - - PROJECT NO. 70-4-6A BENTON DRAWING NO. ENGINEERING, INC. 7 (1 - - - .- - - - - - - - SUMMARY SHEET BORING NO.ant.1 Brown, Moist, Compact Light Yell ,w-brown, Merges into Light Gmy and Light Brown, Saturated, Cwnpact, 30 Percent Gravel to 3 Inches, Cobbles to 5 Inches Light Yellow-brown, Soturakd, Very Firm INE TO MEDIUM SAND GRAVELLY INE TO MEDIUM SAND 18.3 - - 15. 3.4 - - 12.6 98.! - - 20.: I .72 PROJECT NO. 70-4-6A FENTON ENGINEERING, - - (1 - .- - - - - - - - - - - - i - CONSOLIDATION CURVES LOAD IN KlP8 PER SDUARE FOOT o Indicates percent conrol idotion ot field moisture l ‘Indicates percent consol idution after saturation PROJECT NO. -VP. A I. I RFNTc%J FNGINFFRlNr, INC ) DttA~lN6 NO. - - \. - - - - - - .- - - - - - - - - i - + lO.2 I O,‘l 06 06 1.0 2 4 I , &; (11 (/ ! -+ .tT _... -~.-~~--~-~.~~.~~-.~~~I o+- 1 2 k 3 - I- +-. ! I i.-.~~~..-~~-~--.-~-- i I .+~-.-.-A : i .-I~ ~&‘-. 1. I I , T + ~.--..-i.-...--.+.. ‘_ x ~-~-~~---I / i / ! : / 4. 1 --..+-...;..r.. i I ~ I- j-y----+ I I 5- ! y=j--= iii/ii I CONSOLIDATION CURVES LOAD IN #tICS PER SOUARE FOOT 01 1 ;c ! -+--- -A-.. . ..+ 1 Ii! 2 b:+ 1 ..-... --.r-.--++ , ALL. ___..~.. 3 i Lem / I / I 41 ! i ; /I! j / i ~ r _.. -+--4 ..,. --+ i t -.;- I lr ____ --~~. 1 / 1 ie -1. ~-.;.-- i , ii i r-t-~ ~-.-,,q- - - i ~ b 11 i 1 / -4 -- ~,q +-’ -~I.- l--L I . . ..I.~. I I ! 1 ! / 1 Borim 3 I ’ I Ii j j//j/ -1 ~1. + ..-.,- j+fy++- ( / / I- . ~.~. i-.. .-J~.-- ! .._.. ;.+j- i$i~____ / IT!1 T-f _.__ ~ __.._. j-.-.-- ---j- / ’ I ’ / I I I / - .+---;---- I$, / I I r / j T--~---‘, -.-- -1 , o Indicates percent consolidation ot field moisture l Indicates percent consolidation after saturation PROJECT NO. 7c-LAmJ.A I BENTON ENGINEERING, INC. DRAWlNO MO. 1n c.. - - - - - ..- - i 2 .- f 2 t - I G! - - - - - i i : !i iI ;/ Ll Ii I I CONSOLIDATION CURVES LOAD IN KICS PER SOUARE FOOT o Indicates percent conrol idction at field moisture l ,indicctes percent consolidation after saturation 0-n IrrT ..,. r-- I rn”*LII “V. I 7LA-xA BEPITON ENGINEERING. INC. I DRAWINS NO. 1, - - i - ,- - - - - - - - - - .A BENTON ENGINEERING. INC. APPLIED BOIL MECHANlCS - FO”ND*TIONs 6741 EL CAJON BOULEVARD **I4 DIEGO. CALIFORNIA **Ias P”lL,P “ENXING BENTON Pl~SIDIYT CIVIL lHO,NLl” APPENDIX A Unified Soil Clossificotion Chart* SOIL DESCRIPTION GROUP SYMBOL I. COARSE GRAINED, More than half of material is larger than No. 200 sieve size.** GRAVELS CLEAN GRAVELS m half of coarse fraction is larger than No. 4 sieve size but smaller GRAVELS WITH FINES than 3 inches (Appreciable amount of fines) SANDS CLEAN SANDS -than half of coarse fraction is smaller than No. 4 sieve size SANDS WITH FINES (Appreciable amount of fines) II. FINE GRAINED, More than half of material is smaller than No. 200 sieve size.“* SILTS AND CLAYS Liquid Limit Less than 50 SILTS AND CLAYS Liquid Limit Greater than 50 Ill. HIGHLY ORGANIC SOILS GW GP GM GC Well graded grovels, gtavel-sand mixtures, little cr no fines. Pocrly graded gravels, gmvel-sand mixtures, little or no fines. Silty gravels, poorly graded gravel- sand-silt mixtures. Cloyey grovels, poorly graded gravel- sand-clay mixtures. SW SP SM SC Well graded sand, gravelly sands, little or no fines. Poorly graded sonds, gravelly sands, little or no fines. Silty sands, poaly graded sand-silt mixtures. Clayey sands, poorly graded sand-clay mixtures. ML CL OL MH CH OH lncrgonic silts and very fine sands, rock flour, sandy silt or clayey-silt-sand mixtures with slight plasticity. Inorganic clays of low to medium plas- ticity, gravelly clays, sandy cloys, silty clays, lean clays. Organic silts and organic silty-clays of low plasticity. Inorganic silts, micaceous Q diatcma- ceous fine sandy or silty soils, elastic silts. Inorganic clays of high plasticity, fat clays. Organic clays of medium to high plasticity. PT Peat and other highly organic soils. TYPICAL NAMES * Adopted by the Corps of Engineers and Bureau of Reclamation in January, 1952. ** All sieve sizes on this chart are 1J.S. Stondord. BENTON ENGINEERING. INC. - APPLIED SOIL MECHANICS - FOVND*,~IONs < ,’ 67r(l EC CIJO” BOULS”~RD SIN DIEGO. CALIFORNIA DI,l?l - PHlLlP l4EN*ING BENTON c”c*ID~~, . CIYIL ING1WIII1 APPENDIX B *rid D1Z.00; ,.5.,*s. LA HISA? .SO.S~114 Sampling - The undisturbed soil samples ore obtained by forcing a special sampling tube into the undisturbed soils at the bottom of the boring, at frequent intervals below the ground surface. The sampling tube consists of a steel barrel 3.0 inches oukide diameter, with o special cut- ting tip on one end and a double ball valve on the other, and with a lining of twelve thin brass rings, each one inch long by 2.42 inches inside diameter. The sampler, connected to o twelve inch long waste barrel, is either pushed or driven approximately 18 inches into the soil and a six inch section of the center portion of the somple is token for labomtory tesk, the soil being still confined in the brass rings, after extraction from the sampler tube. The samples ore token to the laboratory in close fitting waterproof containers in order to retain the field mois- ture until completion of the tests. The driving energy is calculated OS the overage energy in foot-kips required to force the sampling tube through one foot of soil ot the depth’ot whtch the sample is obtained. Shear Tests - The shear tests ore run using a direct shear machine of the strain control type in which the rote of deformation is approximately 0.05 inch per minute. The machine is so designed that the tests ore mode without removing the somples from the brass liner rings in which they ore se- cured. Each sample is sheared under a normal loud equivalent to the weight of the soil above the point of sampling. In some instances, samples ore sheared under vorious normal loads in order to obtain the internal angle of friction and cohesion. Where considered necessary, samples ore saturated and droined before shearing in order to simulote extreme field moisture conditions. - Consolidation Tests The apparatus used for the consolidation tests is designed to receive one of the one inch - high rings of soil OS it comes from the field. Loads ore applied in several incremenk to the upper surface of the test specimen and the resulting deformations ore recorded at selected time intervals for each increment. Generally, each increment of load is maintained QI the sample until the - rote of deformotion is equal to or less than l/l0000 inch per hour. Porous stones ore placed in contact with the top and bottom of each specimen to permit the ready oddition or release of water. - Expansion Tests - One inch high samples confined in the brass rings ore permitted to air dry at IOYF for at least 48 hours prior to placing into the expansion apparatus. A unit Iad of 500 pounds per square foot is then opplied to the upper porous stone in contact with the top of each sample. i Water is permitted to contact both the top and bottom of each sample through porous stones. Ccntinuous observations ore mode until downward movement stops. The diol reading is recorded and expansion is recorded until the rate of upward movement is less than l/l0000 inch per hour. -