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HomeMy WebLinkAboutEAST DRAKE TERRACE OFFICE PARK PUD - 58 93 - SUBMITTAL DOCUMENTS - ROUND 1 - GEOTECHNICAL (SOILS) REPORTMOISTURE CONTROL The fill material in each layer, while being compacted, shall as nearly as practical contain the amount of moisture required for optimum compaction; and the moisture shall be uniform throughout the fill. The contractor may be required to add necessary moisture to the backfill material in the excavation if, in the opinion of the soils engineer, it is not possible to obtain uniform moisture content by adding water on the fill surface. If, in the opinion of the soils engineer, the material proposed for use in the compacted fill is too wet to permit adequate compaction, it shall be dried in an acceptable manner prior to placement and compaction. COMPACTION When an acceptable, uniform moisture content is obtained, each layer shall be compacted by a method acceptable to the soils engineer and as specified in the foregoing report as determined by the standard Proctor test (ASTM D698-70). Compaction shall be performed by rolling with approved tamping rollers, pneumatic -tired rollers, three - wheel power rollers, or other approved equipment well -suited to the soil being compacted. If a sheepfoot roller is used, it shall be pro- vided with cleaner bars so attached as to prevent the accumulation of material between the tamper feet. The rollers should be so designe that the effective weight can be increased. MOISTURE -DENSITY DETERMINATION Samples of representative fill materials to be placed shall be furnished by the contractor to the soils engineer for determination of maximum density and optimum moisture for these materials. Tests for this determination will be made using methods conforming to requirements of ASTM D698-70. Copies of the results of these tests will be furnished to the contractor. These test results shall be the basis of control for compaction effort. DENSITY TESTS The density and moisture content of each layer of compacted fill will be determined by the soils engineer in accordance with ASTM D1556-68, D2167-66, or D2922-71. Any material found to not comply with the minimum specified density shall be recompacted until the required density is obtained. The results of all density tests will be furnished to both the owner and the contractor by.the soils engineer. -19- APPENDIX A Suggested Specifications for Placement of Compacted Earth Fills and/or Backfills GENERAL A soils engineer shall be the owner's representative to inspect and control all compacted fill and/or compacted backfill placed on the project. The soils engineer shall approve all earth materials prior to their use, the methods of placing, and the degree of compaction obtained. A certificate of approval from the soils engineer will be required prior to the owner's final acceptance of the filling operations. MATERIALS Soils used for all compacted fill beneath interior floor slabs shall be a granular, non -expansive type. Compacted earth backfill placed adja- cent to foundation walls shall be an impervious, non -expansive material. No material having a maximum dimension of greater than six inches shall be placed in any fill. All materials proposed for use in com- pacted fill and/or compacted backfill shall be approved prior to their use by the soils engineer. PREPARATION OF SUBGRADE All topsoil and vegetation shall be removed to a depth satisfactory to the soils engineer before beginning preparation of the subgrade. The subgrade surface of the area to be filled shall be scarified to a minimum depth of six inches, moistened as necessary, and compacted in a manner specified below for the subsequent layers of fill. Fill shall not be placed on frozen or muddy ground. PLACING FILL No sod, brush, frozen material or other deletrious or unsuitable material shall be placed in the fill. Distribution of material in the fill shall be such as to preclude the formation of lenses of material differing from the surrounding material. The materials shall be delivered to and. spread on the fill surface in such a manner as will result in a uniformly compacted fill. Prior to compactijW, each layer shall have a maximum thickness of eight inches; and its upper surface shall be approximately horizontal. -18- r f ..y Boring Number & Depth Liquid Limit Plastic Limit Plasticity Index % Passing 200 Group Index Classitication Unified A.A.S.H.O. Boring No. 4 9 Depth 3.0 3.0 ATTERBERG SUMMARY 3 @ 3.0 7 @ 2.0 29.6 35.8 18.1 17.8 11.5 18.0 64.9 82.2 7.0 11.4 CL CL A-6 (7) A-6 (11) SUMMARY OF TEST RESULTS % Moisture Before Test 16.2 12.6 -17- Dry Density P.C.F. 95.8 93.7 9 @ 7.0 40.4 19.5 20.9 79.0 12.6 CL A-7-6(13) Swelling Pressure PSF 195 PSF 584 PSF � u +f v BORN NO. 7 8 10 DPY' ap DEPTH FT. MOtSTUR` 8.0-9.0 20.3 14.0-15.0 • 2.0-3.0 19.6 3.0-4.0 21.6 7.0-8.0 8.0-9.0 25.0 14.0-15.0 3.0-4.0 11.5 4.0-5.0 8.5 7.0-8.0 6.0-9.0 35.6 14.0-15.0 3.0-4.0 12.6 4.0-5.0 21.0 f 7.0-6.0 8.0-9.0 14.0-15.0 26.2 3.0-4.0 10.8 4.0-5.0 10.5-11.5 16.8 11.5-12.5 18.3 14.0-15.0 SUMMp.Ry OF TEST RESULTS UNCONF ENEG-COM�' Ty STRNCir1—P.S� lOC.8 ` 4,400 94.3 1,2LO 78.0 11(10 3 103.6 ,940 92.2 13,865 94.6 6,030 81.5 2,470 2 101.4 ,500 yJATER SOLUBLE SULFATES—% .018 PENETRATION BLOWS—S 4/12 12/12 6/12 4/12 3/12 15/12 23/12 5/12 14/12 8/12 4/12 12/12 10/12 7/12 ..onDAMPIES, INC. yJATER SOLUBLE SULFATES—% .018 PENETRATION BLOWS—S 4/12 12/12 6/12 4/12 3/12 15/12 23/12 5/12 14/12 8/12 4/12 12/12 10/12 7/12 ..onDAMPIES, INC. SUMMARY OF TEST RESULTS BORING NO. DEPTH FT. % MO!STURE DRY DENSITY I P.C.F. I UNCONFINED COMPRESSIVE STRENGTH-P.S.F. WATER. SOLUBLE SUIfATES —ic PENETRATION BLOWS/INCHES 1 3.0-4.0 11.3 84.0 1,250 4.0-5.0 7/12 7.0-8.0 18.7 105.0 11030 8.0-9.0 2/12 . 14.0-15.0 25.5 5/12 2 3.0-4.0 32.9 86.3 720 4.0-5.0 3/12 7.0-8.0 10.0 101.E 690 .055 8.0-9.0 4/12 - 14.0-15.0 20.3 5/12 3 3.0-4.0 19.0 98.2 1,770 4.0-5.0 4/12 ' 7.0-8.0 29.7 91.1 370 I 8.0-9.0 4/12 14.0-15.0 17.2 10/12 4 3.0-4.0 16.2 94.7 3,190 4.0-5.0 8/12 ' 10.5-11.5 17.9 104.9 840 1i.5-12.5 9/12 14.0-15.0 21.6 7/12 5 3.0-4.0 18.9 85.6 21340 4.0-5.0 8/12 7.0-8.0 14.4 106.9 1,080 8.0-9.0 5/12 14.0-15.0 22.3 4/12 6 3.0-4.0 15.6 86.8 1,920 .038 4.0-5.0 3/12 7.0-8.0 26.6 92.6 210 EMPIRE I LABORATORIES, INC. /1 �.70 O A L.! CONSOLIDATION --SWELL TEST 3.0 BORING NO. 9 DEPTH--A_,Al- DRY DENSITY 96.3#/FT3 MOISTURE 12 6 a i 0.1 0.5 1.0 5 IU APPLIED PRESSURE--TONS/'SQ. FT. i I ao aedd - I I 0.1 0.5 1.0 APPLIED PRESSURE—TONS/SQ. FT. -14- EMPIRE LABORATORIES, INC. 5 10 CONSOLIDATION --SWELL TEST BORING NO. 3 DEPTH -4 r. DRY DENSITY 98.1#/FT3 MOISTURE 19 . 0 % G8 I+ 0 L6 oe 0 ° .64 .t? 0.1 0.5 1.0 S 10 APPLIED PRESSURE—TONS/SQ. FT. 1 - -- J J W 0 .o O� z 1 O H Q 2 0 N Z O V 3 0.1 0.5 1.0 5 10 APPLIED PRESSURE —TONS; SQ. F. -13- EMPIRE LABORATORIES. INC.__- h .62 a .60 .56 5W m CONSOLIDATION --SWELL TEST i.0- BORING NO. 9 DEPTH 8 • 0 DRY DENSITY 101.4#/FT3 °o MOISTURE 1 0 . 0 % 0.1 0.5 1.0 5 10 APPLIED PRESSURE—TONSi SO. FT. 0.1 0.5 1.0 5 1 u APPLIED PRESSURE—TONSi SQ. FT. -12- _ EMPIRE LABORATORIES, INC. _...mom. i LOG OF BORINGS EC,er1/47A o 9 No.10 4990 4985 4980 4975 ovs ►WA m �/ r% y v GN • :rs EMPIRE LABORATORIES, INC f LOG OF BORINGS ELE:/AT/ON No. 5 a. G No. 7 Ala. 0 4990 4985 4980 4975 4970 rs+. mAN rWA p�� wm"@. BAP W W- � MAO' -10- EMPIRE LABORATORIES, INC. ,tl LOG OF BORINGS E'L= YA T/oN No. t o. ? o. 3 h2p. 4990 4985 4975 4970 Co =� ! EPA :mod We VA Note: Elevations interpolated from topographic many_ _ Prepared by Magerf�sh L'Acanriai-aa -9- EMPIRE LABORATORIES, INC w 0 KEY TO BORING LOGS Fill A ' o • d GRAVEL 'v J SILT '. �'�� -SAND & GRAVEL { � ® CLAYEY SILT /•► �'►' � tIt f SILTY SAND 8 GRAVEL (� � SANDY SILT o t COBBLESZi � CLAY " ' !i 1 SAND, GRAVEL &COBBLES �'.�. z SILTY CLAY i E WEATHERED BEDROCK ZJ SANDY CLAY _= � SILTSTGNE BEDROCK I 1. SAND ® CLAYSTONE BEDROCK aSILTY SAND SANDSTONE BEDROCK CLAYEY SAND ® LIMESTONE o a SHELBY TUBE SAMPLE 8 STANDARD PENETRATION DRIVE SAMPLER —e= WATER TABLE 24 HOURS AFTER DRILLING 3/12 Indiutp tlut 3 Alw of • 140 poutw tw,lo t falllnla 30 Imhes woo rpWred to ptn tra» 12 led". -8- k. 144 k h h k c 1.' T r TEST BORING LOCATION PLAN 50UTH 5! ACn?E5 Of T GU4iPO _/0 OPo P1E,- No. !O U M B / A Q5 Na. 6 Ala. 7 Va. '9 A REA 2T No.4 I AREA OrPAKE RDAO -7- EMPIRE LABORATORIES, INC. ninety percent (90%1 of Standard Proctor Den- sity. Puddling st_ould nor. Le permitted as a nears of compaction. (See eppendix A). (5) Gutters and downspouts should he Provided 'or. the structures in suc:i a manner that water from the roof area is discharged wall ix yond the bae)c- fill area. (6) Underground. spr_4-_%1,inq _systems _,hould not be installed within tnn (lo) feet of the structures. in Area II, and t.:is recomwendation should be taken into account in the landscapes planning. (7) Plumbing under sla:js si:ould Le eliminated wher- ever possible in Erna II, since plumbing failures are quite frequently the sources of fret water whic" causes slab r:eave. (fl) An attempt should be made to proportion footing and/or grade beau sizes in such a manner that the unit loads applies to the soil are nearly equal in order that differantial settlements will be minimized. (9) It is recomme:ded that all compaction require- ments specified herein be verified in the field with tensity twst3 performed under the super- vision of an experienced soils engineer. (10 It is recommendad that a regi3terea professional engineer design the substructures and that he tare into account the findi-ags and recc wnda- tions of this report. GENERAL-COW-MNTS The analysis and recommendations submitted in this report are based upon the data obtained from the soil borings performed at the locations indicated on the Location Site Plan. This re- port does not reflect any variations which may occur between these borings. The: nature and extort of variations between the borings may not 1-we-come evident until course of construction. if variations then appear evident, it will be necessary for a re- evaluation of the recorr=sndations of V%is report to be made after performing on -site observations during the construction period and noting thr characteristics of any variations. -6- 1,usidential Streets Select Grav`1 Base Course 6" Asp;ialtic Concrete . ^" 1'utal Pavanent Thickness $ `• Collectcr Streets 3elQct SuLbase 4" Select Gravel 3ase course b" ".sphaltic Co: crete 2" Total Pavement Thickness la° rsterial Streets Select SubLase 7' Select Gravel Base. Course G' Asphaltic Concrete 2" Total Pavemer.L 'thickness 1 ;" All topsoil, organic matter a L' oUi.:r delutrious materials should be stripped and removed fron the street suL'grade prior to placing any fill material, subi-ase or base courstA. ThG fi:.- ished subgrade should be a mi.-inum of three (3) feet ai:,ove existing grounuwater elevations. ?Ul suubase Las" course a.`1d asphaltic concrete small meet C,ty Specifications anc. should be placed in accordance Ltita tl:ise specifications. CENFRAI, RrCO1*A 14TL1,TI(`Q;S - i (1) LaLoratorf teat results indicate that water solu- ble sulfates in the soil are negligible, and a Type I cement may tx: uaed in all concrete. � (2) Finished shade should Le sloped away from the structures on all sides to give positive drain- age. It is suggested that tea percent (11%) for the first ten (10) feet away from the struc- tures he provided. (3) Backfill around the outside perimeter of the structures should be mechanically compacted at optimum moisture to at least eighty-eight per- cent (88%) of Standard Proctor Density. Pud- dling should not be persz:ittced as a means of compaction. (See Apnendix A). (4) All plumbing and utility trenc',Qs uncerlying siah,s and paved areas should Le backfilled with an approver material compacted to at bast -5- feasible providing the finished basement floor slabs are placed a minimum of two (2) feet &Love existing groundwater elevations. if for sane reason the finished basement floor slags are placer! within two (2) feet of the existing ground•eater elevations, the substructure should be designed both structurally and hydrauli- cally to counteract groundwater pressures. i,lso in this cape, .the foundation walla should be waterproofed and a sump pump should be provided in the lower area. Slabs on Grade A-rea I '.11 slabs on grave in this area shvulil Le uncerlain by a ninimum of four (4) inches of gravel or crushed rock devoid of fines. The gravel layer will act as a capillary break and will help to di3tribute floor loads. Area !_I It is fait because of the swelling pressures exerted by the soils in this area, that a floating slab is feasiL-le. It is recoamiended that ulaLs on grac.,e in this area he placed directly on the undisturbed soil which has Leea slightly wettcJ down prior to placira any concrete. I11 slate on grade in this area should be structurally ir6eUend,4:nt of Learing tie:veers. It is fur:.er reYcommen dud that all icon-L,�arirg partitions placed on floor slabs in ti:is area be provided with a slip joint (either top or i.ottcm) such that t3ie pressure applied by heavi: g floor slabs will not !,e transmitted to the :aria . Love. It is emphajized t:,.at if the sut.soils are �-.e:pt dry, zovezent under slabs on grade will not occur; however, if moisture is permitted to reach the suLsvils, heaving :ill occur in this area. . Fill material supporting slats on grade in both areas shoul be a granular -type, non-pk-pansivc3 material compacted at or slightly wet of optimum moisture to at least ninety percent (90% of Standard Proctor Density (See hppendir_ A). All slabs on grad should be reinforced with reinforcing running through the con- struction joints. To minimize shrinkage crac!cs which will de- velop in alai;s on grade, it is recommended that control joints be placed evert fifteen (111) to twenty (20) feet and that the total area contained within t1nesc joints be no greater than four hundred (430) square feet. Streets Soils are classified and group indoxes were determined at various locations within the proposed subdivision for the pur- pose of developing criteria for the pave=nt design. Group in- dexes of the upper soils at the site range from 7.0 to 12.6. Using this as criteria for pavement design, it is recoame:ridee.° that pavement thicknesses For this area be as follows. -4- iZCUMME3OATIONS A ID DISCUSSION Foundation It is our understanding that the proposed area is to ba developed with single and multi-fcuaily units. Luc to differences in tiie physical properties of the soils encountered at the site, the area will be- divided into two (2) parts in this report for t'.:e purposc of determining foundation types and tf:r bearing value's of the :,oily encountered. lrea I will consist of the lower eastern and southern portion of the site (Borings 1, 2, 3, 6 and 7). Area II will consist of the upper northwestern portion of the site (borings 4, 5, 8, 9 and 10) . Area I In view of the soil conditions encountered in this ar_a and the type of structures proposed, it is recommended that ti:e suk- structures be supported by conventional -typo, continuous spread footings. All footings zhould Le founded on tze original undis- turied soil a minimum of t:lirty (30) inches belo.r finished grade for front protection. Footi:_yS founded at this level may be de- signud for a maximum allowable bearing capacity of one thousand five hundred pounds (1,5004) per square foot (dead load plus maximum live load). The predicted settlenent under the aLcve maximum loading should be less than 0.50 inch, generally con- siduresd to be within acceptable tolerances. Area II In view of the soil conditions, encountered over the re- mainder of tiie site, it is recommended that the suL-structures in this area be supported by conventional -type, continuous spread footings and/or continuous grade beams. All footings and/or continuous grade bums snould he founded on the original undisturbed soil a minimum o: thirty (30) inches below finished grade for frost protection. The undisturbed nature of the soils should be verified by a soils engineer prior to placement of any, foundation concrete. Footings and/or grade teams at the above level may Le designed for a maximum allowable bearing capacity of three thousand !pounds (3,000 1.: per square foot (dead load plus maximum live load). To countesrzct 1r,elling pressures which will dOvelop if the subsoils become tutted, all footings and/or grade bears in this area should be designed for a minimum dead load of - one thousand pounds (1,0001) per square foot. The pre>dIcted settlement under the above maximum loading should be less than 0.50 inch, generally considered to be witiiin acceptable toler- ances. basements In view of the depth of greur"`U'ater encountered in both Area I and Area II, it is felt that Lasement construction is w -3- basis for determining tide physical properties of the soils en- countered. moisture contents, dry unit weights, unconfined com- pressive strengths, water sol=le sulfates, swelling potentials and the Rtterberg Limits were determined. A summary of the test data is included on pages 15 t:,rough 17. orsolidation charac- teristics and/or swelling potentials were also determined, and curves showing this data are included on pages 12 through-14. SOIL A.lb GRO!'hDWATER CONnITICKS The soil profile at t;ie sit: ecr.sists of strata of materi- als arranged in different comt;inations. In order of increasing depths, they are as follows; (1) SiltyTopsoil: A one (1) foot layer of silty topsoil overlios tt.e site. The upper six (6) inches of the topsoil have been penetrated by plant roots and organic matter and should not he used as a bearing soil or as a backfill ma- terial. (2) Silk Clams•: A layer of silty clay underlies tine topsoil and extends to depths of four (4) to eight and one-half (©�) feet below t::e sur- face. The silty clays are plastic and exhibit low to moderata bearing characteristics in their generally damp to moist natural state. In the area of Borings 4, 5, 8, 9 and 10, the upper silty clays are dry and as a result ex- hit;it a high dry strength; Lowever, when wet- ted, the shearing strength of the clays are re- duced and generally exiiibit moderate swelling pressures. (3) Sandy, Silt Clay: A stratum of sandy silty clay underl es the upper silty clays. This material was encountered at depths of four (4) to eight and one-half (8�) feet below the sur- face and extends to depths of greater than fif- teen (15) feet.below the surface. Lenses of clean to silty Sand were encountered at various levels in Borings 3 ar.d 6. The sandy, silty clays aro plastic, ex)iiL-it low to moderate bearing characteristics =nA' consolidate readily when loaded. (4) Groundwater: At the time of the investigation, free groundwater was encountered at depths of nine (9) to greater than fifteen (15) feet below t1:e surface. however, groundwater elevations in this aria are subject to change depending upon seasonal variations and irrigation flows on or adjacent to ts:e property. -2- FFPC1P OF a SOILS AaU FOUNOATICU INVESTIC:.4TIOM SCOPE This report presents the rf�sults of a Soils and Foundation Investigation prepared for the prcpesed development consisting I Of the south fifty-one (51) acres of Guard properties. The in- vestigation was carried out by means of test borings and la):,o- ratory testing of samples cbtaineO from these borings. The objectives of tliis investigation were to (1) determine the suitability of the site for construction purposes, (2) make recommendations regarding tt.e design of the substructures, and (3) recommend certain precautions which should be taken because of adverse soil and/or groundwater conditions. SITE INVESTIGATION The field investigation, carried out on Gctober 24, 1972, consisted of drilling, logging, and sampling ten (10) test bor- ings. The locations of t::c test borings are shown on the Test Borina Location Plan included on page 7 of this report. Boring logs prepared from the field logs are shown on pages 9 through 11 . These logs show soils encountered, location of sampling, and groundwater at the time of the investigation. All borings were advanced with a four -inch diameter, continuous -type, power -flight auger drill. During the drillinc operations, a field engineer from Empire Laboratories, Inc., was present and made a continuous visual inspection of the soils en- countered. SITE LOCATION AND DESCRIPTION The proposed site is located in Southeast Fort Collins, Colorado, South of Vanguard Park. More particularly, the site is descriLed as a tract of land located in the West 1/2 of the Southeast 1/4 of Section 24, Township 7 :forth, Range 69 West of the 6th P.M., Larimer County, Colorado. The site is under cultivation, relatively flat and has minor drainage to the east LABOP.ATORY TESTS AND EXAMINATI(:Ii Samples ottained from the test borings were subjected to testing and inspectirn in the la2,oratory to provide a.,sound -nr Empire Laburatories, Inc. Material, and Foundation Engineers November 8, 1972 Jungmeyer 3 Company Post Office Box I70 Fort Collins, Colorado 80521 Attention: WaLley Jungmeyer Gentlemen: We are pleased to submit our iYeport of a Soils and Foundation Investigation prepared for the proposed subdivision located in Southeast Fort Collins, as reauuated. Based upon our findings in the subsurface, we feel that the aita is suitable for the proposed construction, providing the design criteria and recommendations as set ford: in this re- port are met. The aecompaniing report presents our findings in the subsurface and our recommendations cased upon theae findings. Very truly yours, EMPIRE LABORATORIES, INC. --�, D d Cheater C. Smith, P.S. ' n Vice President �* H `t8V3 K p h � ?' rro \lA Ft S/.•FEf1 t'� OFFICE AND LABORATORY-214 NORTH HOWES • P.O. BOX 149 • FORT COLLINS. COLORADO 8= • TELEPHONE AREA 385i484aD= -ii- e Of:O:ltt t .:................................... °,c:ttcr Of ".a-maittal................................ =_ = .. ............................................. I - E• :eat 'sorin•_ :..ovation ?'Ian ............................ 7 �:oy .:o springs ....................................... 8 i,or, of c -.6....................................... 9-11 ;on::olilation Test Data .............................. Sai wary Of T-?St RCSults ........................... .. �. t IJ 17 AupendixA ........................................... 18-19 i 9 n.q.. 0 REPORT OF A SOILS ALID FOUNDATION INVESTIGATION FOR JUNGvR:YER S COMPPINY FORT COLLINS, COLORADO r ,451 �;krk T ,&WV« � � 4ex PROJECT NO. 1310-72 BE: GUARD PROPERTY I VA . it 9