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Home My WebLink AboutSubsoil Study for Foundation Designl.*,.iiffifimfmii[:Ë;;-'" An Employcc Owncd Compony 5020 County Road 154 Glenwood Springs, CO 81601 phone: (970) 945-7988 fax: (970) 945-8454 email : kaglenwood@kumarusa.com www.kumarusa.com Office Locations: Denver (HQ), Parker, Colorado Springs, Fort Collins, Glenwood Springs, and Summit County, Colorado SUBSOIL STUDY FOR FOUNDATION DESIGN AND GEOLOGIC HAZARDS REVIEW PROPOSED RESIDENCE AND BARN 264s COVNTY ROAD 241 (EAST ELK CREEK ROAD) GARFIELD COUNTY, COLORADO PROJECT NO.22-7-748 MAY 8,2023 PREPARED FOR: STEVE BECKLEY 2645 COUNTY ROAD 241 NEW CASTLE, COLORADO 81647 sbecklev@,slenwoodcaverns.com TABLE OF CONTENTS PIIRPOSE AND SCOPE OF STUDY PROPOSED CONSTRUCTION SITE CONDITIONS GEOLOGIC HAZARDS ASSESSMENT..... ROCKFALL DEBRIS FLOW, FLASH FLOODING, AND EROSION HYDROCOMPACTIVE SOILS SEASONALLY SHALLOW GROUNDWATER AND PERCF{ED WATER FIELD EXPLORATION SUBSURFACE CONDITIONS FOUNDATION BEARING CONDITIONS . DESIGN RECOMMENDATIONS FOTINDATIONS FOTINDATION AND RETAINING WALLS FLOOR SLABS UNDERDRAIN SYSTEM ............. SURFACE DRAINAGE LIMITATIONS........... REFERENCES FIGURE 1 - LOCATION OF EXPLORATORY BORINGS FIGURE 2 - LOGS OF EXPLORATORY BORINGS FIGURE 3 - LEGEND AND NOTES FIGURE 4 - S\MELL-CONSOLIDATION TEST RESULTS FIGURE 5 - GRADATION TEST RESULTS TABLE 1. SUMMARY OF LABORATORY TEST RESULTS I 1- 5 a -2- -2- -J- -J- -J- -4- 4 I 5 5 6 7 7 I ..........- I - ........- 9 - Kumar & Associates, lnc. @ Projec{ No.22-7-748 PURPOSE AND SCOPE OF STUDY This report presents the results of a subsoil study for a proposed residence and barn to be located at 2645 County Road 241 , Garfield County, Colorado. The proj ect site is shown on Figure I . The purpose of the study was to develop recommendations for the foundation design. The study was conducted in accordance with our agreement for geotechnical engineering services to Steve Beckley dated March 23, 2423. A field exploration program consisting of exploratory borings was conducted to obtain information on the subsurface conditions. Samples of the subsoils obtained during the field exploration were tested in the laboratory to determine their classification, compressibility or swell and other engineering characteristics. The results of the field exploration and laboratory testing were analyzedto develop recommendations for foundation types, depths and allowable pressures for the proposed building foundation. This report summarizes the data obtained during this study and presents our conclusions, design recommendations and other geotechnical engineering considerations based on the proposed construction and the subsurface conditions encountered. PROPOSED CONSTRUCTION The proposed barn will be a one or two-story structure approximately located in the area of Borings I and2. Ground floor will be slab-on-grade. The proposed residence is to be constructed in the future and plans have not yet been developed but will likely be a one or two- story structure possibly with a walk-out lower level with slab-on-grade or structural over crawlspace floors, and typical of the area. The proposed residence will be located generally in the area of Borings 3 and 4. Grading for the structures is assumed to be relatively minor with cut depths between about 4 to 5 feet. We assume relatively light foundation loadings, typical of the proposed type of construction. When building locations, grading and loading information have been developed, we should be notified to re-evaluate the recommendations presented in this report. SITE CONDITIONS The subject site is currently developed with an existing resìdence and various outbuildings. The building sites are accessed by a gravel driveway. Topography at the site is valley bottom with gentle to moderate slopes generally down to the west. East Elk Creek runs through the site to the west of the existing and proposed development. Sandstone/Siltstone outcrops to the east of the site, across and above County Road 241 (East Elk Creek Road). Vegetation at the site consists of native grass and weeds, sage brush, scrub oak, and cottonwood trees. Kumar & Aseociates, lnc. @ Project No.22-7-748 1 GEOLOGIC HAZARDS ASSESSMENT We visited the site on May 5,2023 to observe the geologic conditions at the proposed development areas. The project site geology should not present major constraints or unusually high risks to the proposed development. There are, however, several conditions of a geologic nature that should be considered in the project planning and design. Geologic conditions that should be considered, their potential risks, and mitigations to reduce the potential risks are discussed below. The site could experience moderate levels of earthquake related ground shaking. ROCKFALL Sandstone/Siltstone bedrock of the maroon formation outcrop to the east of the proposed development areas east of County Road 241 (East Elk Creek Road). The area between the outcrop and the proposed development areas is heavily vegetated with dense scrub oak and scattered cottonwood trees. There is a small Ritchie catchment ditch along the uphill side of East Elk Creek Road beneath the roadcut into the bedrock. No signs of recent rockfall at or immediately above the proposed development areas on the subject property were observed and it is our opinion that the risk of rockfall impact to the proposed development is low. DEBRIS FLOW, FLASH FLOODING, AND EROSION The proposed development is located about 100 to 200 feet east of East Elk Creek and is on an elevated bench about 10 to 20 feet above the creek elevation. East Elk Creek is well incised through the property and no minor debris flow channels were observed in the proposed development areas. The banks of East Elk Creek through the proposed development areas appear stable and excessive accelerated erosion does not appear to be occurring. There are a few relatively small drainage basins along the valley sides of the East Elk Creek main valley but these generally have no or very small associated alluvial fans. No debris flow channels from theses drainages were observed through the proposed development areas. If blockage and./or avulsion of the main East Elk Creek stream channel were to occur upslope of the subject site, minor deposition of mud at the site is possible. While the possibility of the deposition of mud at the subject site exists if the East Elk Creek channel were to become blocked, no remnant debris flow channels were observed in the area of the proposed development. Some cleanup of mud may be necessary if the deposition of mud were to occur but mitigation such as berms or constructed channels, in our opinion, does not appear to be warranted. Positive drainage away from the proposed buildings is especially important. Surface drainage recommendations are provided below. Kumar & Associates, lnc. @ Project No.22.7-748 --r- HYDROCOMPACTIVE SOILS The hydrocompaction potential of the bearing soils at the proposed development locations was evaluated during the subsoil study for foundation design (see below). The risk to the proposed development due to hydrocompactive soils will be reduced provided the foundation design recommendations presented below are followed. SEASONALLY SHALLOW GROUNDWATER AND PERCHED WATER Groundwater was encountered at a depth of 18 feet in one of the borings drilled for the subsoil study (see below), well below the proposed excavation depths for the proposed development. Below-grade construction, such as retaining walls, crawlspace areas deeper than 3 feet, and basement areas, should be protected from wetting and hydrostatic pressure buildup due to perched water by an underdrain system. SEISMICITY Historic earthquakes within 150 miles of the project site have typically been moderately strong with magnitudes less than 5.5 and maximum Modified Mercalli Intensities less than VI (Widmann and Others, 1998). The largest historic earthquake in the project region occurred in 1882. It was located in the northern Front Range and had an estimated magnitude of about M6.4 + 0.2 and a maximum intensity of VII. Historic ground shaking at the project site associated with the 1882 earthquake and the other larger historic earthquakes in the region does not appear to have exceeded Modified Mercalli Intensity VI (Kirkham and Rogers,2000). Modified Mercalli Intensity VI ground shaking should be expected during a reasonable exposure time for the residences, but the probability of stronger ground shaking is low. Intensity VI ground shaking is felt by most people and causes general alarm, but results in negligible damage to structures of good design and construction. The seismic soil profile at the project site should be considered as Class C,very dense soil and soft rock, as described in the 2018 International Building Code, unless site specifïc shear wave velocity studies show otherwise. Based on our experience in the area and the anticipated ground conditions, liquefaction is nqt a design consideration. Using the USGS National Earthquake Hazard Reduction Progtam online database, the following probabilistic ground motion values are reported for the project site. Intensity Measure Type Intensity Measure Level 2 percent in 50 Years 0.2 Sec. Spectral Acceleration Ss 0.360 1.0 Sec. Spectral Acceleration Sr 0.079 Kumar & Associates, lnc. @ Project No. 22-7-748 -4- The USGS National Earthquake Hazard Reduction Program online database also indicates a peak ground acceleration (PGA) of 0.2229 at the subject site. The PGA is the lower of either the deterministic or probabilistic value with a 2Yo exceedance probability for a 50-year exposure time at the project site (statistical recurrence interval of 2,500 years). The region is in the Uniform Building Code Seismic Risk Zone l. Based on our current understanding of the earthquake hazard in this part of Colorado, we see no reason to increase the commonly accepted seismic risk zone for the area. FIELD EXPLORATION The field exploration for the project was conducted on April20,2023. Four exploratory borings were drilled at the locations shown on Figure I to evaluate the subsurface conditions. The borings were advanced with 4 inch diameter continuous flight augers powered by a truck- mounted CME-458 drill rig. The borings were logged by a representative of Kumar & Associates, Inc. Samples of the subsoils were taken with 1% inch and 2 inch I.D. spoon samplers. The samplers were driven into the subsoils at various depths with blows from a 140 pound hammer falling 30 inches. This test is similar to the standard penetration test described by ASTM Method D-l586. The penetration resistance values are an indication of the relative density or consistency of the subsoils. Depths at which the samples were taken and the penetration resistance values are shown on the Logs of Exploratory Borings, Figure 2. The samples were returned to our laboratory for review by the project engineer and testing. SUBSURFACE CONDITIONS Graphic logs of the subsurface conditions encountered at the site are shown on Figure 2. The subsoils consist of about Y, to I foot of topsoil overlying silty to very silty sand with scattered gravel, underlain by relatively dense silty sand and gravel at a depth of 19 feet in Borings 1 and2 and a depth of 8 feet in Boring 3. The relatively dense silty sand and gravel was encountered directly beneath the topsoil in Boring 4. Drilling in the dense granular soils with auger equipment was difficult due to the cobbles and boulders and drilling refusal was encountered in the deposit at a depth of 7 feet in Boring 4. Laboratory testing performed on samples obtained from the borings included natural moisture content and density and gradation analyses. Results of swell-consolidation testing performed on a relatively undisturbed drive sample of very sandy silt and clay, presented on Figure 4, indicate moderate compressibility under conditions of loading and wetting and a low hydrocompression potential when wetted under a constant 1,000 psf surcharge. Results of gradation analyses Kumar & Associates, lnc. o Project No.22-7-748 -5- performed on small diameter drive samples (minus IYz or 2-inch fraction) of the coarse granular subsoils are shown on Figures 5 and 6. The laboratory testing is summarized in Table 1. Free water was encountered in Boring I at a depth of l8 feet at the time of drilling and the subsoils were moist to wet with depth. FOUNDATION BEARING CONDITIONS The upper clayey silt and sand subsoils at the site possess low to moderate bearing capacity and, in general, moderate settlement potential, especially when wetted. Lightly loaded spread footings bearing on the natural soils should be feasible for foundation support of the structures with some risk of settlement. The risk of settlement is primarily if the bearing soils were to become wetted and precautions should be taken to prevent wetting. DESIGN RECOMMENDATIONS FOUNDATIONS Considering the subsurface conditions encountered in the exploratory borings and the nature of the proposed construction, we recommend the buildings be founded with spread footings bearing on the natural soils. The design and construction criteria presented below should be observed for a spread footing foundation system. 1) Footings placed on the undisturbed natural soils should be designed for an allowable bearing pressure of 1,500 psf. Based on experience, we expect settlement of footings designed and constructed as discussed in this section will be about 1 inch or less. 2) The footings should have a minimum width of 16 inches for continuous walls and 2 feet for isolated pads. 3) Exterior footings and footings beneath unheated areas should be provided with adequate soil cover above their bearing elevation for frost protection. Placement of foundations at least 36 inches below exterior grade is typically used in this area. 4) Continuous foundation walls should be heavily reinforced top and bottom to span loçal anomalies such as by assuming an unsupported length of at least 12 feet. Foundation walls acting as retaining structures should also be designed to resist lateral earth pressures as discussed in the "Foundation and Retaining Walls" section of this report. Kumar & Astociates, lnc. o Projec-t No.22-7-748 -6- Any existing fill, topsoil and loose or disturbed soils should be removed and the footing bearing level extended down to the relatively dense natural soils. The exposed soils in footing area should then be moistened and compacted. A representative of the geotechnical engineer should observe all footing excavations prior to concrete placement to evaluate bearing conditions. FOIINDATION AND RETAINING WALLS Foundation walls and retaining structures which are laterally supported and can be expected to undergo only a slight amount of deflection should be designed for a lateral earth pressure computed on the basis of an equivalent fluid unit weight of at least 55 pcf for backfill consisting of the on-site soils. Cantilevered retaining structures which are separate from the structures and can be expected to deflect sufficiently to mobilize the full active earth pressure condition should be designed for a lateral earth pressure computed on the basis of an equivalent fluid unit weight of at least 50 pcf for backfill consisting of the on-site soils. All foundation and retaining structures should be designed for appropriate hydrostatic and surcharge pressures such as adjacent footings, traffîc, construction materials and equipment. The pressures recommended above assume drained conditions behind the walls and a horizontal backfill surface. The buildup of water behind a wall or an upward sloping backfill surface will increase the lateral pressure imposed on a foundation wall or retaining structure. An underdrain should be provided to prevent hydrostatic pressure buildup behind walls. Backfîll should be placed in uniform lifts and compacted to at least 90% of the maximum standard Proctor density at a moisture content near optimum. Backfill in pavement and walkway areas should be compacted to at least 95% of the maximum standard Proctor density. Care should be taken not to overcompact the backfill or use large equipment near the wall, since this could cause excessive lateral pressure on the wall. Some settlement of deep foundation wall backfïll should be expected, even if the material is placed correctly, and could result in distress to facilities constructed on the backfill. The lateral resistance of foundation or retaining wall footings will be a combination of the sliding resistance of the footing on the foundation materials and passive earth pressure against the side of the footing. Resistance to sliding at the bottoms of the footings can be calculated based on a coefficient of fliction of 0.40. Passive pressure of compacted backfill against the sides of the footings can be calculated using an equivalent fluid unit weight of 375 pcf. The coefnicient of friction and passive pressure values recommended above assume ultimate soil strength. Suitable factors of safety should be included in the design to limit the strain which will occur at the ultimate strength, particularly in the case of passive resistance. Fill placed against s) 6) Kumar & Associates, lnc, @ Projec't No. 22-7-748 -7- the sides of the footings to resist lateral loads should be a compacted to at least 95% of the maximum standard Proctor density at a moisture content near optimum. FLOOR SLABS The natural on-site soils, exclusive of topsoil, are suitable to support lightly loaded slab-on-grade construction. To reduce the effects of some differential movement, floor slabs should be separated from all bearing walls and columns with expansion joints which allow unrestrained vertical movement. Floor slab control joints should be used to reduce damage due to shrinkage cracking. The requirements for joint spacing and slab reinforcement should be established by the designer based on experience and the intended slab use. A minimum 4 inch layer of free- draining gravel should be placed beneath basement level slabs to facilitate drainage. This material should consist of minus 2-inch aggregate with at least 50% retained on the No. 4 sieve and less than2Yo passing the No. 200 sieve. All fill materials for support of floor slabs should be compacted to at least95Yo of maximum standard Proctor density at a moisture content near optimum. Required fill can consist of the on-site coarser granular soils devoid ofvegetation, topsoil and oversized rock. LJNDERDRAIN SYSTEM Although free water was encountered deeper than proposed excavation elevations during our exploration, it has been our experience in the areathat local perched groundwater can develop during times of heavy precipitation or seasonal runoff. Frozen ground during spring runoff can create a perched condition. We recommend below-grade construction, such as retaining walls, crawlspace areas deeper than 3 feet, and basement areas, be protected from wetting and hydrostatic pressure buildup by an underdrain system. The proposed shallow foundation of the proposed barn should not need a perimeter foundation drain, provided that the exterior foundation wall backfill is well-compacted and good surface drainage, as described below, is maintained around the structure. If installed, the drains should consist of PVC drainpipe placed in the bottom of the wall backfill surrounded above the invert level with free-draining granular material. The drain should be placed at each level of excavation and at least I foot below lowest adjacent finish grade and sloped at a minimum lYo to a suitable gravity outlet. Free-draining granular material used in the underdrain system should contain less than 2%o passing the No. 200 sieve, less than 50% passing the No. 4 sieve and have a maximum size of 2 inches. The drain gravel backfill should be at least LYz feet deep and covered with filter fabric such as Mirafi 140N or 160N. An impervious membrane such as 20 mil PVC should be placed beneath the drain gravel in a trough shape and attached to the foundation wall with mastic to prevent wetting of the bearing soils. Kumar & Associates, lnc. o Projec{ No. 22-7-748 -8- SURFACE DRAINAGE The following drainage precautions should be observed during construction and maintained at all times after the buildings have been completed: 1) Inundation ofthe foundation excavations and underslab areas should be avoided during construction. 2) Exterior backfill should be adjusted to near optimum moisture and compacted to at least 95%o of the maximum standard Proctor density in pavement and slab areas and to at least 90Yo of the maximum standard Proctor density in landscape areas. 3) The ground surface surrounding the exterior of the building should be sloped to drain away from the foundation in all directions. We recommend a minimum slope of 6 inches in the first 10 feet in unpaved areas and a minimum slope of 3 inches in the first t0 feet in paved areas. Free-draining wall backfill should be capped with about 2 feet of the on-site soils to reduce surface water infïltration. 4) Roof downspouts and drains should discharge well beyond the limits of all backfill. 5) Landscaping which requires regular heavy irrigation should be located at least 5 feet from foundation walls. LIMITATIONS This study has been conducted in accordance with generally accepted geotechnical engineering principles and practices in this arcaatthis time. We make no warranty either express or implied. The conclusions and recommendations submitted in this report are based upon the data obtained from the exploratory borings drilled at the locations indicated on Figure 1, the proposed type of construction and our experience in the area. Our services do not include determining the presence, prevention or possibility of mold or other biological contaminants (MOBC) developing in the future. If the client is concemed about MOBC, then a professional in this special field of practice should be consulted. Our findings include interpolation and extrapolation of the subsurface conditions identified at the exploratory borings and variations in the subsurface conditions may not become evident until excavation is performed. If conditions encountered during construction appear different from those described in this report, we should be notified so that re-evaluation of the recommendations may be made. This report has been prepared for the exclusive use by our client for design pu{poses. We are not responsible for technical interpretations by others of our information. As the project evolves, we should provide continued consultation and field services during construction to review and monitor the implementation of our recommendations, and to veriff that the recommendations have been appropriately interpreted. Significant design changes may require additional analysis Kumar & Associates, lnc. @ Project No.22-7-748 -9- or modifications to the recommendations presented herein. We recommend on-site observation of excavations and foundation bearing strata and testing of structural fill by a representative of the geotechnical engineer. Respectfully Submiued, Kumar & Associates, lnc. Robert L. Duran, P. Reviewed by: ì Daniel E. Hardin, P.E. RLD/kac REFERENCES Kirkham, R.M. and Others, 2002. Evaporite Tectonísm in the Lower Roaring Fork River I/alley, West-Central Colorado, in Kirkham, R.M., Scott, R.B. and Judkins, T.W. eds.. Late Cenozoic Evaporite Tectonísm and Volcanisrn ín West Centrøl Colorado. Geological Society of America Special Paper 366, Boulder, Colorado. Widmann, Beth L., Kirkham, Robert M., and Rogers, William P., 1998. Preliminary Quaternøry Fault and Fold Map and Database of Colorado. Colorado Geological Surve¡ Open File Report 98-8. Í/ u ttJ 6T1H2, Kumar & Associates, lnc.6 Project No.22-7-748 Septic I\lo Wood House BORING Boundary Clww¿Iw Ran¿lt Proposed Buíldirq I APPROXIMATE SCALE_FEET 22-7-748 Kumar & Associates LOCATION OF EXPLORATORY BORINGS Fig. 1 WC=24.5 *4=7 -200=61 BORING 1 EL. 100' BORING 2 EL. 102' BORING 5 BORING 4 o 0 6/12 4/12 WC=16.7 DD=1 01 5/12 32/12 5 56/12 WC=21 .2 DD=94 -2OO=57 6/12 WC=19.6 DD=1 01 -200=55 5/12 WC=12.9 Dù=l12 -200=30 52/12 +4=63 -200=1 0 Fl¡Jl¡ll! I-¡-o- l¿Jo 10 s/12 20/12 18/12 10 l-l¡Jl¡Jl! I-FfL l¡Jô t5 11/12 WC=18.8 DD= 1 O9 +4=12 -2OO=73 14/12 15s/12 20 20/12 2023/12 20/12 25 2550/5 18/12 50 30 WC=7-6 +4=48 -2OO=24 22-7-748 Kumar & Associates LOGS OF EXPLORAÏORY BORINGS Fig. 2 E LEGEND N m W F I TOPSOIL SAND AND SILT, FIRM, SLIGHTLY MOIST, BROWN, ORGANICS. SAND MOIST (SM); SILTY TO VERY SILTY, SCATTERED GRAVEL, LoOSE TO MEDIUM DENSE, VERY TO WET, BROWN. GRAVEL AND COBBLES (GM); SANDY TO VERY SANDY, SILTY, MEDIUM DENSE TO VERY DENSE, MOIST TO WET, MIXED BROWN. DRIVE SAMPLE, z-INCH I.D. CALIFORNIA LINER SAMPLE. DRIVE SAMPLE, 1 3/9-|NCH l.D. SPLIT SPOON STANDARD PENETRATION TEST ^2". DRIVE SAMPLE BLOW COUNT. IND¡CATES THAT 6 BLOWS OF A 140-POUND HAMMERo/ '' FALLTNc Jo TNcHES wERE REQUTRED To DRIvE THE SAMpLER t2 tNcHES. 4 oepru ro wATER LEvEL ENcouNTERED AT THE TIME oF DRrLLrNc. t PRACTICAL AUGER REFUSAL. NOTES 1. THE EXPLORATORY BORINGS WERE DRILLED ON APRIL 20, 2025 WITH A 4_INCH-DIAMETER CONTINUOUS-FLIGHT POWER AUGER. 2. THE LOCATIONS OF THE EXPLORATORY BORINGS WERE MEASURED APPROXIMATELY BY PACING FROM FEATURES SHOWN ON THE SITE PLAN PROVIDED. 3. THE ELEVATIONS OF THE EXPLORATORY BOR]NGS WERE MEASURED BY HAND LEVEL. 4. THE EXPLORATORY BORING LOCATIONS AND ELEVATIONS SHOULD BE CONSIDERED ACCURATE ONLY TO THE DEGREE IMPLIED BY THE METHOD USED. 5. THE LINES BETWEEN MATERIALS SHOWN ON THE EXPLORATORY BORING LOGS REPRESENT THE APPROXIMATE BOUNDARIES BETWEEN MATERIAL TYPES AND THE TRANSITIONS MAY BE GRADUAL. 6. GROUNDWATER WAS NOT ENCOUNTERED IN THE BORINGS AT THE TIME OF DRILLING. 7. LABORATORY TEST RESULTS: WC = WATER CONTENT (%) (ASTM D2216); DD = DRY DENSITY (pcf) (Asru D2216); +4 = PERCENTAGE RETAINED ON NO. 4 SIEVE (ASTM 06915); -200 = PERCENTAGE PASSING NO. 2O0 SIEVE (ASTM D1140). 22-7-748 Kumar & Associates LEGEND AND NOTES Fig. 5 SAMPLE OF: Sondy Silt ond Cloy FROM: Boring2@2.5' WC = 16.7 ?6, DD = f 01 pcf cd mt b. rtDrú¡cld, ADDITIONAL COMPRESSION UNDER CONSTANT PRESSURE DUE TO WETTING APPUED1.0 1 0 àq j*1 l¡¡ =ant-z z.o F- o_< Jooz()ts -4 -5 -6 Fig. 4Kumar & Associates SWELL-CONSOLIDATION TEST RESULTS22-7 -7 48 ? I ! 62 E Ë too 90 ao 70 ao 50 Æ s 20 to o HYDROMETER ANALYSIS SIEVE ANALYSIS lvE Ræx6 Z¿ HRS 7 HRS iltt at tt ¡tô Æ CTEAR SQUARE OPT¡{IXGS ttt- tl^- t ttr'z /1 I ¡ I I I I j l i i i t I I I'+- -- '. I I I ¡ ! I I I I rl o 10 20 30 â 50 60 70 æ 90 'too z E, ë ,oo9 .t 50 I-&5 DIAMETER OF CLAY TO SILT COBBLES GRAVEL 7 '6 SAND UQUID UMIT SAMPLE OF: Sondy Sill ond CloY 32 '6 PTASTICITY INDEX SILT AND CLAY 61 X FROM: Boring I O 10' ond 15' Combined 2 2 t00 90 ao 70 60 50 Æ s 2ø to o HYDRO¡¡ETER ANALYSIS SIEVE ANÀLYSIS TT¡E R€MXOS 2¡+ Hns 7 HR:i lqvtr &tx tutN tt U.S. SNDARD SÉRIES Aı Æ an tta ato s CMR SQUARE OPEXIXGS at^. tfl' I 1/r'5'A- t l! ìi I ' !I i ! I I I I i ¡ I !iI ilir ! i L I I i t!i.ii ¡ I 1 ii 1 o lo 2C) 50 10 50 60 70 ao 90 - E È 1m .500 OF INM CLAY TO SILT COBBLES GRAVEL 12 % SAND UQUID UMIT SAMPLE OF: Sondy Slll ond CloY 15?d PTASTICITY INDEX SILT AND CI.AY 73 % FROM:Boring2O15' Th6! l€t 6ull¡ oÞply only lo lhe romol.¡ whlch TaE lotl.d, Tho tælfåg roporl lholl nol b. roPÞducrd, lxcoDl ln full, vllhoul lhs wrltt.n ooorävol of Kumor & Atroclolo, lnc. Sidvc onolysl¡ loflng lt Þ.rfom.d ln occordoncà r¡th ASn¡ D6915, ASft¡ D792E' ASItl Cl56 q¡d/or AStl¡ Dll,l{!. GRAVELSAND MEDTUM ICO¡nSg FINE COARSEFINE GRAVELSAND FINE COARSEFINEMEDTUM ICOARSE 22-7-748 Kumar & Associates Fis. 5GRADATION TEST RESULÏS : n 4 2 1(þ 90 æ 70 ao 50 6 5{l 20 to o I{YOROUETÉR ANALYSIS SIEV€ ANALYSIS 4HË 7 HnS NTE READIIGA dtr leylx 4lx tvtx ai ¡tß t1i ß M SQI'ÆE ffiIffi !ta- ala- t tt - !. t t J. i -l I l I SAND GRAVEL FINE MEDIUM FINE COARSE to x) :to ß 50 æ 70 ao 90 100 e a E E Ë .t 50 DIAMETER OF CLAY TO SILT COBBLES GRAVEL ß % SAND uQulD uHlT SAMPLE OF: Sllty Sond ond Grovef z8x PI.ASTICITY TNDEX SILT AND CIAY 21 X FROH: BorÍng 5 o f0'ond 15' Combinôd Ê B 100 90 ao 70 80 50 Æ :to 20 fo o o 10 20 :lo tlo 50 æ m ao 90 too =E, þÊ OF IN CLAY TO SILT COBBLES GRAVEL 65 X SAND 27 UQUID UMIT SAIIPLE OF: Sllghlly Silty Sond ond Gravel % PLASTICITY INDEX SILT AND CLAY IO % FRol¡:Borlng4o5' lh6c tst uull¡ qpph onty lo lt. smÞh¡ uhlch w!ru l.d.d. Th. Ldlne nÞorl lho¡l nol b! roÞrcduc.d. !r@pl ln full. çilhout lùo wtlllcnqppddl of Kumqr & Alwlolc, lnc. Slárc qnolyslc t€tlng k Þ.rtomrd ln sccordoncr rtth ASTI¡ D6915, ASft¡ D792E, ASTU C156 qnd/or Asn¡ Dtt/l{r- HYDROYETER ÂNÀLYSIS SIEI/E ANALYSIS ¡im u.s. sßMRo ffiF ¡s m as ¡t3 lto{¿4 HnS 7 r{R!;(¡ vrx t5 ltf, wlf,lrtxdtx rllE nEADlllCS T9UIN 1 l I I SAND GRAVEL FINE MEDIUM ICOARSE FINE COARSE 22-7-748 Kumar & Associates GRADATION TEST RESULTS Fig. 6 ICrti.iHi[ffifËfri''*nË;n'n""'TABLE 1SUMMARY OF LABORATORY TEST RESULTSNo.22.7.74J21BORING510+15Combined51552%10+15Combined5lfrtDEPTHSAMPLE LOCATION7,612.918.8t9.6t6.724.52r.2(olNAÏURALMOISTURECONTENT112109101I0I94NATURALDRYDENSITYlocflGRAD,48127("/"1GRAVEL63281532SAND(%)\TION27243073536I57PERCENTPASSING NO.200 SIEVEI0lohlLIQUID LIM]TlololPLASIICINDËXlosfìUNCONFINEDCOMPRESSIVESTRENGTHSlightly Silty Sand andGravelSilty Sand and GravelSilty Sand with GravelSandy Silt and ClayVery Sandy Silt and ClaySandy Silt and ClaySandy Silt and ClaySandy Silt and ClaySOIL TYPE