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HomeMy WebLinkAboutSoils Report 06.22.2012GRAND JUNCTION LINCOLN DeVORE, Inc. GEOTECHNICAL ENGINEERS - GEOLOGISTS 1441 Motor Street Grand Junction, CO 81505 June 22, 2012 WPX Energy Rocky Mountain LLC c/o D&.1 Gardner Excavating 134 Gardner Ln. Parachute, CO 81635 Tel: (970) 242-8968 Fax: (970) 242-1561 gj1dem@earthlink.net Re: Open Excavation Observation; Shop Building, Rulison Evaporation Facility, Rulison, CO Gentlemen: As requested, Grand Junction Lincoln DeVore personnel completed a foundation excavation evaluation at the above -referenced site on 6-12-2012. The purpose of this observation and evaluation was to determine the type and condition of the soils on the site and to relate their engineering characteristics to foundation reactions of the proposed structure. This letter contains general recommendations for construction of a small commercial shop foundation, but it is not a foundation design and may not be used as such. Our conclusions and recommendations for this site arc presented below. Conclusions: The foundation pads for this small, 20'x40' steel -framed shop building was found to be placed on man-made fill soils. These man-made fill soils were reportedly placed in the latter part of 2011 and have been in place for approximately 6 months. These soils were probed, and a relatively undisturbed specimen was taken for laboratory testing. It was determined these man-made fill soils have an allowable bearing capacity of 2,200 psf. Our observations on this site indicate that the pad foundation type to support the structural steel frames will probably be adequate. Our observations of the site revealed the fill slopes appear to be in good condition, and no areas of instability or potential instability were observed. The recommendations contained in this report, including site drainage, are considered important. Soil Classification: Soil Type No. I was classified as a sandy lean clay (CL) under the Unified Classification System. These soils are man-made fill, apparently constructed for this particular building pad. The building pad excavations were probed to determine soil consistency, and a sample was obtained from the northeast exterior foundation pad. These soils were found to have an in-place soil density of 102.1 pcf. The moisture content was found to be 14.5%, at a depth of 628 inches below the excavation. This soil is plastic and may be somewhat sensitive to changes in moisture content. As this soil is found in a relatively dry condition, it may undergo very slight expansion with the entry of small amounts of moisture, but it will undergo slight collapse/long-term consolidation upon the addition of larger amounts of moisture or if over -loaded. One dimensional consolidation tests using the consolidation apparatus ASTM D-2435 were performed on relatively undisturbed samples of the soil. Upon test saturation, a very slight collapse of 0.26% was measured, with 1.83% consolidation occurring at an applied load of2,050 ps£ Upon further test loading, 4.17% consolidation WPX Energy Rocky Mountain LLC Open Excavation Observation; Shop Building, Rulison Evaporation Facility; Rulison, CO June 22, 2012 Page 2 occurred at an applied load of 4,100 psf. The maximum allowable bearing capacity for this man-made fill soil was found to be 2,200 psf, with 500 psf minimum dead load pressure required. Man-made Fill: This site is on man-made fill with the thickness of fill, which was placed for this building pad, ranging from virtually no new fill in the west and northwest portion of the building pad to approximately 3 feet of fill below the northeast corner, which was tested for consolidation properties, to approximately 6-8 feet of fill beneath the southeast comer of the structure. The exposed fill in the excavation and on the slopes was probed and found to be stiff. The fill had the appearances of being compacted in a moist condition but did appear to be compacted on the "dry side" of the optimum moisture, ASTM D-698. The in- place soil density obtained from the northeast foundation pad excavation was 102.1 pcf This is approximately 90% to 92% of Standard Proctor density for similar soils, derived from the afuvial/colluvial soils in this area. Soil Moisture Conditions: The soils in the excavation at foundation level were found to be damp to moist. No free water was noted in the excavation. Foundation Type Recommended: Grand Junction Lincoln DeVore would typically recommend that a steel -framed structure in this area be underlain by a perimeter concrete grade beam, and pads placed beneath the steel frame bearing points. Such a foundation system would typically incorporate pads of a minimum of 24"x24" wide to account for the building loads and to provide some amount of up -lift resistance due to wind loads in this area. The excavated pads on this site were somewhat excess of the 24" minimum pad size that we would typically recommend; but but to the potential of adverse wind loading on this site, the larger pads are probably appropriate. Reinforcing: The foundation shall be reinforced as shown on the foundation design. No changes shall be made to this placement of reinforcing without written approval of the design engineer or architect If a site-specific foundation design has not been accomplished for this site, it may be appropriate to use the reinforcing schedule from the relevant table(s) provided by the building manufacturer. Floor Slabs: Non-structural floor slabs on grade, if any, should be positively separated from all structural portions of this building and allowed to float freely. Frequent scoring (control joints) of the slabs should be provided to allow for possible shrinkage cracking of the slab. These control joints should be placed to provide maximum slab areas of approximately 200 to 360 square feet. Any man-made fill placed below floor slabs on grade should be compacted to a minimum of 90% of its maximum modified proctor dry density (ASTM D-1557). These soils should be placed at a moisture content conducive to the required compaction (usually proctor optimum moisture content ± 2%). Drainage and Grading: Adequate site drainage should be provided in the foundation area, both during and after construction, to prevent the ponding of water and the wetting or saturation of the subsurface soils. We recommend that the ground surface around the structure be graded so that surface water will be carried quickly away from the building. The minimum gradient within 10 fcct of the building will depend on surface WPX Energy Rocky Mountain LLC Open Excavation Observation; Shop Building; Rulison Evaporation Facility; Rulison, CO June 22, 2012 Page 3 landscaping. We recommend that paved areas maintain a minimum gradient of 2% and that landscaped areas maintain a minimum gradient of S%. It is further recommended that roof drain downspouts be carried at least 5 feet beyond all backfilled areas and discharge a minimum 10 feet away from the structure. Proper discharge of roof drain downspouts may require the use of subsurface piping in some areas. Under no circumstances should a "dry well discharge" be used on this site unless specifically sited by a geotechnical engineer. Planters, if any, should be constructed so that moisture is not allowed to seep into foundation areas or beneath slabs or pavements. The existing drainage on the site must either be maintained carefully or improved. We recommend that water be drained away from structures as rapidly as possible and not be allowed to stand or pond within 15 fent of the building or foundation. We recommend that water removed from one building not be directed onto the backfill areas of adjacent buildings. Provided that all recommendations found herein pertaining to site surface drainage, grading, and soil compaction are closely followed, a perimeter foundation drain would not be required. Backfill: To reduce settlement and aid in keeping water from reaching beneath this building, all backfill around this building should be mechanically compacted to a minimum of 90% of its maximum modified proctor dry density (ASTM D-1557). The only exception to this would be the components of the perimeter foundation drain, if any. All backfill should be composed of the native soils and should not be placed by soaking, jetting or puddling. All backfill placed in utility trenches around this structure or below foundation walls should be mechanically compacted to a minimum of 90% of its maximum modified proctor dry density (ASTM D-1557). These soils should be placed at a moisture content conducive to the required compaction (usually proctor optimum content ± 2%). Cement Type: Type II, Type I-II, or Type II -V cement is recommended for all concrete in contact with the soils on this site. Calcium chloride should not be added to a Type II, Type I-II, or Type II -V cement under any circumstances. Remarks: We recommend that the bottom of all foundation components rest a minimum of 3 feet below finished grade or as required by the local building codes. Foundation components must not be placed on frozen soils. Limitations: This report is issued with the understanding that it is the responsibility of the owner or his representative to ensure that the information and recommendations contained herein are brought to the attention of the architect and engineer for the project and are incorporated into the plans. In addition, it is his responsibility to ensure that the necessary steps are taken to see that the contractor and his subcontractors carry out these recommendations during construction. The findings of this report are valid as of the present date. However, changes in the conditions of a property can occur with the passage of time, whether they be due to natural processes or the works of man on this or adjacent properties. In addition, changes in acceptable or appropriate standards may occur or may result from legislation or the broadening of engineering knowledge. Accordingly, the findings of this report may be invalid, wholly or partially, by changes outside our control. Therefore, this report is subject to review and should not be relied upon after a period of three years. WPX Energy Rocky Mountain LLC Open Excavation Observation; Shop Building; Rulison Evaporation Facility; Rulison, CO June 22, 2012 Page 4 The recommendations of this report pertain only to the site investigated and are based on the assumption that the soil conditions do not deviate from those described in this report. If any variations or undesirable conditions are encountered during construction, or if the proposed construction will differ from that planned on the day of this report, Grand Junction Lincoln DeVore should be notified so that supplemental recommendations can be provided, if appropriate. Grand Junction Lincoln DeVore makes no warranty, either expressed or implied, as to the findings, recommendations, specifications, or professional advice except that they were prepared in accordance with generally accepted professional engineering practices in the field of geotechnical engineering. Respectfully submitted, GRAND JUNCTION LINCOLN DeVORE, INC. 0 :°0• . so uvicii is d:zzwizi, p' 30590 N 1.1 by: Edward M. Morris, P.E. Principal Engineer Digitally signed by Edward M. Morris, P.E. GJLD Job No. 94512-G1 Edward M. Morris P.E. DN: cn=Edward M. Monis, P.E., o=Grand Junction Lincoln- DeVore, Inc., ou, email=gjldem@earihlink.net. c=US Date: 2012.06.22 09:08:11 -06'00' Soil Sample: SANDY LEAN CLAY (CL) Si)tstone/Mudstone Fragments Sample No.: I (Typical) Geologic Origin: MAN-MADE FILL - From Local Alluvial/Colluvial Soil Test by: GS Natural Water Content (w): 14.5% Building Pad.: NE Depth: 6" In -Place Density (pcf): 102.1 Soil Sp ific Gravity (Gs): 2.67 Estimated 10 COBBLE to GRAVEL 80 D I SAND ! SILT to CLAY I 125 75 50 37,5 25 19. 12.5 9 5 4.75 2 0.85 0.425 0.15 0.07' 0.02 0.005 50 30 20 10 0 Sieve 5" 3" 2" 1-112" 1" 3,4" 1/2" 3/8" #4 #10 #20 #40 #100 #200 (mm) 125 75 50 37.5 25 19 12.5 9.5 4.75 2 0.85 0.425 0.15 0.075 0.02 0.005 article Graig Size {mm} % Passing 100 99 94 90 85 82 72.1 58 40 Maximum Size Allowed By Sampler 2-1/2" Effective size Cu Cc Plastic Limit (PL) Liquid Limit (LL) Plasticity Index (PI) Skempton's Activity Shrinkage Limit (SL) Shrinkage Ratio 18 38 20 0.3 DIRECT SHEAR: CD Peak Shear Angle: deg. Tan Shear. Cohesion: psf MOISTURE / DENSITY RELATIONSHIP: D-698 A D 4718 - 0% Rock Correction pc pcf ASTM Method: Max. Dry Density : Optimum Moisture : HVEEM-CARMANY: 'R' Value @ 300 psi: Displacement 300 psi: Expansion @ 300 psi: mm Res. FHA Soil Swell: Swell psf psf Remolded Sample ALLOWABLE BEARING (net): Standard Penetration (SPT): Unconfined Compression (qu): COLLAPSE @ Wetting: CONSOLIDATION: CONSOLIDATION: SULFATE SALTS: PERMEABILITY: K (20 C): Remolded 2200 psf by Consolidometer psf by Penetrometer psf 0.26% 1.83% 4.17% 2000+ 1025 psf 2050 psf 4100 psf ppm cm/sec Cat ocf SOIL ANALYSIS and SUMMARY 1 GRAND JUNCTION LINCOLN - DeVORE, Inc. Geotechnical Consultants Grand Junction, Colorado SHOP BUILDING - 20'x 40' _ Rulison Evaporation Facility, Rulison, CO. WPX c/o D & J Gardner Excay. Battlement Mesa, Colorado Date 6-21-2012 Job No. 94512 -GJ Drawn EMM 0 0. 0 0. O 0. J tl 0 0. J-1 0.5 W 0 -0.5 -1 Oz -1-2 Q -2.5 -3 p -3.5 CO ZO -4.5 U -5 -5.5 W -6 C) -6.5 ID -7 0- -7.5 100 SL SOIL COLLAPSE or 65 63 —��•uu11� .—rara•taa SI. Mill 4NLI.PY'iit 11111.11M11111111MME -- 107.9 of o.2G% WHEN SATURATRO ... ._ �._iommo.....■ °f0.21s9' 1111/i111 18.8% RATED mmu CONSOLIDATION (%) -0- altl.� .��i!SAL IIiIIIIMM r.r�- SAMPLE UNLOAD/RELOAD 61SAAIPLE ' SATURATION (%) 59% _ 92% 92% 111111111‘11 - I III UNLOAD/RELOAD 11 IINIIMINNII ! ! •••M ®� IIIII yawn M/WMUNI' TEST LOAD •iiuii t WIN _- SAMPLE--.I� REBOUND ' iiiiI 59 57 55 � ■ U�v11iL�L__ uuu al— MI :ft= � . 111111 ■\�11I SAMPL 1 REBOUND I••I UII,I--.►Nisi Ii`i1■`g'II 531111__ ■iu1ui__ lifirI i � .■VIII 100 1000 APPLIED TEST LOAD - psf The Consolidation Test (ASTM 0-2435, History) Was Run By Subjecting The Soli Specimen To A 'Seating' Load To Remove Slack From The Apparatus And To Provide An Accurate Point Of Beginning. The Test Begins With The Specimen At Approximate Natural Moisture Content . The Porous Stones Are Dry to Slightly Moist To Approximate the Specimen Condition For The Initial Test Loads, Prior To Sample Inundation, The Sample Is Loaded To Approximate Overburden Pressure, Unloaded And Reloaded The Sample Is Then Inundated With Water, Any Swell Or Collapse Is Allowed To Occur And The Loading is Continued. After The Maximum Teat Load, The Soil Specimen Is Unloaded To Measure Rebound And My 10000 Swelling Potential Atter Consolidation. 1000 APPLIED TEST LOAD - psf LOAD SUMMARY 110 1025 0.26 0.00 1.12 6.85 8200 psf SEATING LOAD psf SAMPLE SATURATED % SOIL COLLAPSE % SOIL EXPANSION / SWELL D-4546 B % SAMPLE REBOUND @ UNLOAD % MAXIMUM CONSOLIDATION psf MAXIMUM TEST LOAD 2200 psf Max. BEARING CAPACITY@ 2% Canso/ SOILS EXHIBITED SLIGHT SWEL.UNG 10000 DURING THE UNLOAD/RELOAD PHASE. RELOAD SWELL PRESSURE of 1200 psf. FHA SWELL PRESSURE estimated 500 psf. INITIAL MAXIMUM LOAD SI. Mill 4NLI.PY'iit 11111.11M11111111MME -- 107.9 of o.2G% WHEN SATURATRO ... ._ SOIL MOISTURE (%) 14.5% 18.8% 19.5% CONSOLIDATION (%) -0- 6.85% 5.73% VOID RATIO (e) SAMPLE UNLOAD/RELOAD 1— = ' SATURATION (%) 59% _ 92% 92% i i - I I ! ! ®� — al= M/WMUNI' TEST LOAD t WIN _- SAMPLE--.I� REBOUND INI al— 1000 APPLIED TEST LOAD - psf LOAD SUMMARY 110 1025 0.26 0.00 1.12 6.85 8200 psf SEATING LOAD psf SAMPLE SATURATED % SOIL COLLAPSE % SOIL EXPANSION / SWELL D-4546 B % SAMPLE REBOUND @ UNLOAD % MAXIMUM CONSOLIDATION psf MAXIMUM TEST LOAD 2200 psf Max. BEARING CAPACITY@ 2% Canso/ SOILS EXHIBITED SLIGHT SWEL.UNG 10000 DURING THE UNLOAD/RELOAD PHASE. RELOAD SWELL PRESSURE of 1200 psf. FHA SWELL PRESSURE estimated 500 psf. V SOIL #:I SOIL TYPE : CL TEST HOLE #: NE Pad SAMPLE Gs: 2.67 DIAMETER (in.): 2.5 AREA (inches): 4.9087 SAMPLE Gs WAS ESTIMATED SOIL CONSOLIDATION ASTM D-2435 1 GRAND JUNCTION LINCOLN - DeVORE, Inc. Geotechnical Consultants Grand Junction, Colorado SHOP BUILDING - 20'x 40' Rulison Evaporation Facility, Rulison, CO. WPX do D & J Gardner Excay. Battlement Mesa, Colorado Date 6-21-2012 Job No. 94512 -GJ Drawn EMM INITIAL MAXIMUM LOAD V FINAL LOAD SOIL DENSITY (pci) 102.1 107.9 106.7 SOIL MOISTURE (%) 14.5% 18.8% 19.5% CONSOLIDATION (%) -0- 6.85% 5.73% VOID RATIO (e) 0.656 0.544 0.562 SATURATION (%) 59% _ 92% 92% V SOIL #:I SOIL TYPE : CL TEST HOLE #: NE Pad SAMPLE Gs: 2.67 DIAMETER (in.): 2.5 AREA (inches): 4.9087 SAMPLE Gs WAS ESTIMATED SOIL CONSOLIDATION ASTM D-2435 1 GRAND JUNCTION LINCOLN - DeVORE, Inc. Geotechnical Consultants Grand Junction, Colorado SHOP BUILDING - 20'x 40' Rulison Evaporation Facility, Rulison, CO. WPX do D & J Gardner Excay. Battlement Mesa, Colorado Date 6-21-2012 Job No. 94512 -GJ Drawn EMM