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HomeMy WebLinkAbout1.16 Geotechnical Report 640 White Avenue Grand Junction, Colorado 81501 Phone: 970-255-8005 Fax: 970-255-6818 Info@huddlestonberry.com July 20, 2017 Project#00302-0047 Austin Civil Group, Inc. 123 N. 7th Street Grand Junction, CO 81501 Attention: Mr. Jim Joslyn Subject: Geotechnical Investigation Pro Gas Bulk Propane Lot 1, Block 12 Travelers Highlands Parachute, Colorado Dear Mr. Joslyn, This letter presents the results of a geotechnical investigation conducted by Huddleston-Berry Engineering & Testing, LLC (HBET) for the proposed Pro Gas Bulk Propane facility at Lot 1, Block 12 of the Travelers Highlands near Parachute, Colorado. The site location is shown on Figure 1. The proposed construction is anticipated to include placement of a petroleum storage tank. The scope of our investigation included evaluating the subsurface conditions at the site to aid in developing foundation recommendations for the proposed construction. Site Conditions At the time of the investigation, the site was open and fairly flat. Vegetation consisted primarily of weeds and grasses. The site was bordered to the northeast by existing industrial property, to the northwest by Walker Avenue and Interstate 70, to the southwest by 4th Street, and to the southeast by Scarrow Avenue. Subsurface Investigation The subsurface investigation included two test pits as shown on Figure 2 – Site Plan. The test pits were excavated to a depth of 8.0 feet below the existing ground surface. Typed test pit logs are included in Appendix A. As indicated on the logs, the subsurface conditions at the site were slightly variable. Test Pit TP- 1 encountered 1.5 feet of granular road base above lean clay with gravel and cobbles fill materials to a depth of 4.0 feet. The fill was underlain by brown, moist medium stiff lean clay with trace gravel and cobbles to the bottom of the excavation. Groundwater was not encountered in TP-1 at the time of the investigation. Travelers Highlands #00302-0047 07/20/17 X:\2008 ALL PROJECTS\00302 - Austin Civil Group\00302-0047 Travelers Highlands\200 - Geo\00302-0047 LR072017.doc 2 Test Pit TP-2 encountered 1.0 foot of topsoil above brown, moist, medium stiff lean clay with trace gravel and cobbles to the bottom of the excavation. Groundwater was not encountered in TP-2 at the time of the investigation. Laboratory Testing Laboratory testing was conducted on samples of the native soils encountered in the test pits. The testing included grain size analysis, Atterberg limits determination, natural moisture content determination, water soluble sulfates content determination, and maximum dry density and optimum moisture content (Proctor) determination. The laboratory testing results are included in Appendix B. The laboratory testing results indicate that the native clay soils are moderately plastic. Due to the presence of gravel and cobbles, undisturbed sample of the native soils were unable to be collected for swell/consolidation testing. However, based upon the Atterberg limits of the material and based upon our experience with similar soils in the vicinity of the site, the native clay soils are anticipated to be slightly expansive. Water soluble sulfates were detected in the site soils in a concentration of 0.3%. Foundation Recommendations Based upon the results of the subsurface investigation and nature of the proposed construction, shallow foundations are recommended. Spread footings and mat structural slabs are both appropriate foundation alternatives. However, as discussed previously, fill materials were encountered in TP-1. In addition, the native clay soils are anticipated to be slightly expansive. Therefore, in order to limit the potential for excessive differential movements, it is recommended that existing fill materials be completely removed from below foundations and replaced with structural fill. However, a minimum of 24-inches of structural fill is recommended below the entire foundation. Due to their plasticity, the native clay soils are not suitable for reuse as structural fill. Imported structural fill should consist of a granular, non-expansive, non-free draining material such as crusher fines or CDOT Class 6 base course. Unless it can be demonstrated that the materials are not free-draining, pit-run materials should not be used as structural fill. Prior to placement of structural fill, it is recommended that the bottom of the foundation excavation be scarified to a depth of 6 to 9 inches, moisture conditioned, and compacted to a minimum of 95% of the standard Proctor maximum dry density, within ± 2% of the optimum moisture content as determined in accordance with ASTM D698. Structural fill should extend laterally beyond the edges of the foundation a distance equal to the thickness of structural fill. Structural fill should be moisture conditioned, placed in maximum 8-inch loose lifts, and compacted to a minimum of 95% of the standard Proctor maximum dry density for fine grained soils and modified Proctor maximum dry density for coarse grained soils, within ± 2% of the optimum moisture content as determined in accordance with ASTM D698 and D1557, respectively. Travelers Highlands #00302-0047 07/20/17 X:\2008 ALL PROJECTS\00302 - Austin Civil Group\00302-0047 Travelers Highlands\200 - Geo\00302-0047 LR072017.doc 3 For structural fill consisting of imported granular materials and foundation building pad preparation as recommended, a maximum allowable bearing capacity of 1,500 psf may be used. In addition, a modulus of subgrade reaction of 250 pci may be used for structural fill consisting of crusher fines or base course. Foundations subject to frost should be at least 36-inches below the finished grade. Any retaining walls should be designed to resist lateral earth pressures. For backfill consisting of the native soils or imported granular, non-free draining, non-expansive material, we recommend that the walls be designed for an active equivalent fluid unit weight of 55 pcf in areas where no surcharge loads are present. An at-rest equivalent fluid unit weight of 75 pcf is recommended for braced walls. Lateral earth pressures should be increased as necessary to reflect any surcharge loading behind the walls. As discussed previously, water soluble sulfates were detected in the site soils in a concentration of 0.3%. This concentration of sulfates represents a severe degree of potential sulfate attack on concrete. Type V is specified by the International Building Code (IBC) for this concentration of sulfates. However, Type V cement can be difficult to obtain in Western Colorado. Where Type V cement is unavailable, Type I-II sulfate resistant cement is recommended. General Notes The recommendations included above are based upon the results of the subsurface investigation and on our local experience. These conclusions and recommendations are valid only for the proposed construction. As discussed previously, the subsurface conditions at the site were slightly variable. However, the precise nature and extent of subsurface variability may not become evident until construction. The recommendations contained herein are designed to reduce the risk and magnitude of structural movements and it is extremely critical that ALL of the recommendations herein be applied to the design and construction. However, HBET cannot predict long-term changes in subsurface moisture conditions and/or the precise magnitude or extent of any volume change in the native soils. Where significant increases in subsurface moisture occur due to poor grading, improper stormwater management, utility line failure, excess irrigation, or other cause, during or after construction, significant movements are possible. In addition, the success of the structure foundations, slabs, etc. is critically dependent upon proper construction. Therefore, HBET should be retained to provide materials testing, special inspections, and engineering oversight during ALL phases of the construction to ensure conformance with the recommendations herein. We are pleased to be of service to your project. Please contact us if you have any questions or comments regarding the contents of this report. Travelers Highlands #00302-0047 07/20/17 X:\2008 ALL PROJECTS\00302 - Austin Civil Group\00302-0047 Travelers Highlands\200 - Geo\00302-0047 LR072017.doc 4 Respectfully Submitted: Huddleston-Berry Engineering and Testing, LLC Michael A. Berry, P.E. Vice President of Engineering 07/20/17 FIGURES Garfield Coun ty, Colo rado Prin ted: 7/20 /2 017 at 1 :22 :48 PM Disc laimerThis is a co mp ilatio n o f reco rds as th ey ap p ear in th e G arfield Co un ty Office s aff ecting th e area sh own . This d rawin g isto b e u sed o nly f or refe re nc e p urp ose s an d the Co un ty is n ot resp on sible for any in acc uracies he rein co n taine d. Garfie ld C o unty Land Explorer Co pyright Gar fie ld Cou nty, Colo rado | A ll Rights Reser ved© Gar f ield Count y Land Explor er ¬1 inch = 1,505 fe et 1 inch = 0.28 m ile s 0 0.4 0.80.2 Miles Gar fie ld Cou nty Colorad oGarfield County Coloradowww.gar field-county.com Gar field C oun ty Pr inted by Web User (970) 242-7540123 N 7th Street, Suite 300 Grand Junction, Colorado 81501AUSTIN CIVIL GROUP, INCA C GLand Planning Civil Engineering Development ServicesM:\PROJECTS\1061.0007 Brach Bulk Propane Parachute\Dwg\C3d\Production Dwg\ACG-BRACH-PRO-PARA-BASE1.dwg, 6/22/2017 11:47:26 AM, DWG To PDF.pc3 APPENDIX A Typed Test Pit Logs Granular Road Base Lean CLAY with Gravel and Cobbles (FILL), brown with thin red layers, moist, medium stiff Lean CLAY with trace Gravel and Cobbles (cl), brown, moist, medium stiff Bottom of test pit at 8.0 feet. NOTES GROUND ELEVATION LOGGED BY CM EXCAVATION METHOD Mini-Excavator AT TIME OF EXCAVATION dry AT END OF EXCAVATION dry AFTER EXCAVATION --- TEST PIT SIZE EXCAVATION CONTRACTOR Client GROUND WATER LEVELS: CHECKED BY MAB DATE STARTED 6/26/17 COMPLETED 6/26/17 DEPTH(ft)0.0 2.5 5.0 7.5 GRAPHICLOGATTERBERG LIMITS MATERIAL DESCRIPTION SAMPLE TYPENUMBERFINES CONTENT(%)RECOVERY %(RQD)BLOWCOUNTS(N VALUE)POCKET PEN.(tsf)DRY UNIT WT.(pcf)MOISTURECONTENT (%)LIQUIDLIMITPLASTICLIMITPLASTICITYINDEXPLASTICITYINDEXPAGE 1 OF 1 TEST PIT NUMBER TP-1 CLIENT Austin Civil Group PROJECT NUMBER 00302-0047 PROJECT NAME Travelers Highlands PROJECT LOCATION Parachute, CO GEOTECH BH COLUMNS 00302-0047 TRAVELERS HIGHLANDS.GPJ GINT US LAB.GDT 7/17/17Huddleston-Berry Engineering & Testing, LLC 640 White Avenue, Unit B Grand Junction, CO 81501 970-255-8005 970-255-6818 Lean CLAY with Organics (TOPSOIL) Lean CLAY with trace Gravel and Cobbles (CL), brown, moist, medium stiff *** Lab Classified GB1 Bottom of test pit at 8.0 feet. GB 1 851630171313 NOTES GROUND ELEVATION LOGGED BY CM EXCAVATION METHOD Mini-Excavator AT TIME OF EXCAVATION dry AT END OF EXCAVATION dry AFTER EXCAVATION --- TEST PIT SIZE EXCAVATION CONTRACTOR Client GROUND WATER LEVELS: CHECKED BY MAB DATE STARTED 6/26/17 COMPLETED 6/26/17 DEPTH(ft)0.0 2.5 5.0 7.5 GRAPHICLOGATTERBERG LIMITS MATERIAL DESCRIPTION SAMPLE TYPENUMBERFINES CONTENT(%)RECOVERY %(RQD)BLOWCOUNTS(N VALUE)POCKET PEN.(tsf)DRY UNIT WT.(pcf)MOISTURECONTENT (%)LIQUIDLIMITPLASTICLIMITPLASTICITYINDEXPLASTICITYINDEXPAGE 1 OF 1 TEST PIT NUMBER TP-2 CLIENT Austin Civil Group PROJECT NUMBER 00302-0047 PROJECT NAME Travelers Highlands PROJECT LOCATION Parachute, CO GEOTECH BH COLUMNS 00302-0047 TRAVELERS HIGHLANDS.GPJ GINT US LAB.GDT 7/17/17Huddleston-Berry Engineering & Testing, LLC 640 White Avenue, Unit B Grand Junction, CO 81501 970-255-8005 970-255-6818 APPENDIX B Laboratory Testing Results 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 0.0010.010.1110100 PI Cc 1730 CuLL PL 13 GRAIN SIZE DISTRIBUTION COBBLES GRAVEL 85.112.5PERCENT FINER BY WEIGHT3 1002416 301 2006 10 501/2 HYDROMETERU.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS 1403420 406 601.5 8 143/4 3/8 SAND GRAIN SIZE IN MILLIMETERS coarse fine LEAN CLAY(CL) ClassificationSpecimen Identification Specimen Identification D100 D60 D30 D10 %Gravel coarse SILT OR CLAYfinemedium %Sand %Silt %Clay 0.7 14.2 TP-2, GB1 TP-2, GB1 6/2017 6/2017 CLIENT Austin Civil Group PROJECT NUMBER 00302-0047 PROJECT NAME Travelers Highlands PROJECT LOCATION Parachute, CO GRAIN SIZE 00302-0047 TRAVELERS HIGHLANDS.GPJ GINT US LAB.GDT 7/17/17Huddleston-Berry Engineering & Testing, LLC 640 White Avenue, Unit B Grand Junction, CO 81501 970-255-8005 970-255-6818 0 10 20 30 40 50 60 0 20 40 60 80 100 ML CL MH CH 85 Specimen Identification CL-ML P L A S T I C I T Y I N D E X LIQUID LIMIT Classification 30 17 LEAN CLAY(CL) LL PL PI 13 ATTERBERG LIMITS' RESULTS 6/2017 #200 TP-2, GB1 CLIENT Austin Civil Group PROJECT NUMBER 00302-0047 PROJECT NAME Travelers Highlands PROJECT LOCATION Parachute, CO ATTERBERG LIMITS 00302-0047 TRAVELERS HIGHLANDS.GPJ GINT US LAB.GDT 7/17/17Huddleston-Berry Engineering & Testing, LLC 640 White Avenue, Unit B Grand Junction, CO 81501 970-255-8005 970-255-6818 90 95 100 105 110 115 120 125 130 135 140 145 150 0 5 10 15 20 25 30 LEAN CLAY(CL) TP-2 Sample No.: ASTM D698A PL PI 13DRY DENSITY, pcf3/4" WATER CONTENT, % 17 Test Method: MOISTURE-DENSITY RELATIONSHIP LL GRADATION RESULTS (% PASSING) ATTERBERG LIMITS Curves of 100% Saturation for Specific Gravity Equal to: 2.80 2.70 2.60 116.0 14.5 Sample Date:6/26/2017 17-0363 Source of Material: Description of Material: 30 TEST RESULTS Optimum Water Content % #200 Maximum Dry Density PCF #4 85 100 100 CLIENT Austin Civil Group PROJECT NUMBER 00302-0047 PROJECT NAME Travelers Highlands PROJECT LOCATION Parachute, CO COMPACTION 00302-0047 TRAVELERS HIGHLANDS.GPJ GINT US LAB.GDT 7/17/17Huddleston-Berry Engineering & Testing, LLC 640 White Avenue, Unit B Grand Junction, CO 81501 970-255-8005 970-255-6818