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Home My WebLink AboutZ-7919-D Application 4A �, ANDERSON ENGINEERING CONSULTANTS, INC. 10205 ROCKWOOD ROAD — LITTLE KJCK, ARKANSAS 72204 PHONE (501) 455-4545 FAX (501) 455-4552 September 20, 2006 Job No.: 10835 Mr. John Burkhalter, P.E. % The Holloway Firm, Inc. 200 Casey Drive Maumelle, Arkansas 72113 Re: Limited Geotechnical Investigation Proposed Residential Development — 2°d and Bond Streets Little Rock, Arkansas Dear Mr. Burkhalter: We are providing this letter report to present the results of our limited geotechnical investigation for the above referenced project. We understand that the proposed project is to consist of a multiple high rise residential complexes and is in the very early planning stages to determine the feasibility of construction. You requested our services to perform preliminary borings in an effort to determine the condition of the underlying soils and indicate likely foundation alternatives that would be required for the structures. FIELD INVESTIGATION The field investigation consisted of the drilling and sampling of two test borings at the proposed site as shown on the Vicinity Map, Plate 1. The location of the borings was suggested by the client at the approximate locations shown on the Plan of Borings, Plate 2. The boreholes were advanced using the wash drilling method. Soil sampling consisted of performing Standard Penetration test in general accordance with ASTM D 1556 at intervals selected by the geotechnical engineer. Soil samples obtained from the sampler were visually classified in the field by the soils technician and placed in containers for transport to the laboratory. The stratigraphy and N -values are summarized on the boring logs, provided on Plates 3 and 4. The classifications indicated on the boring logs are in general accordance with the field classification system for soil and rock exploration with the keys to these classifications provided on Plates 5 through 8. The Unified Soil Classification System (ASTM D 2487) is provided for reference on Plate 9. Several test pits excavated by the client were observed by the geotechnical engineer prior to this investigation. Based on these observations, varying amounts of sandy silt with rubble exist across the site and was verified by the borings. Though the borings indicate these materials range in thickness from 5.0 to 6.0 feet, further variation is likely based on the test pits. We understand that the site was previously utilized as an uncontrolled dump site for a demolition contractor. Concrete rubble, bricks and other various items were observed. Determination of the Geotechnical Engineering — Environmental Assessments m Quality Control Of Construction Materials Anderson Engineering Consultants, Inc. Mr. John Burkhalter, P.E. % The Holloway Firm, Inc. Page 2, 09/21/06 extent and condition of the previously placed fill was beyond the scope of this investigation. Further investigation utilizing borings and/or test pits will aid in the estimation of the quantity of these materials and is recommended prior to final design. The soils encountered beneath the fill materials was found to consists primarily of loose to medium dense silty sand (SM) to an approximate depth of 13.0 feet. As indicated on the boring logs, these soils became more dense with depth, and contained gravel size particles beyond a depth of 40.0 to 50.0 feet. The blow counts obtained in the two borings consistently exceeded 50 blows for 12 inches beyond a depth of 35.0 feet indicating very dense sands. Hard, weathered gray shale with quartzitic sandstone seams was encountered at an approximate depth of 62.0 feet. The borings were terminated at a depth of 5.0 feet into this material. We anticipate that the shale in this area will extend to significant depths. The long term groundwater level was not determined due to the wash drilling method. Due to the nature of the soils and the proximity of the site to the Arkansas River, we anticipate the water level with coincide with the river level. Perched water, however, is likely in the near surface soils, especially within the uncontrolled fill materials. The nature of the soils encountered indicates they are moisture sensitive and will pump and become unstable once the moisture content surpasses optimum. SEISMICITY The seismic analyses require the selection of appropriate site coefficients and other seismic values that can be established from subsurface conditions, guidelines set forth by local, state and federal codes, and historic seismic information. The structure's foundations should be designed using guidelines as set forth in either the 1999 Standard Building Code as required by Arkansas Act 1100-1991 (and subsequent amendments) or the 2000 International Building Code. The predominant soil type is silty sand (SM) that varies from loose to very dense underlain by the Jackfork Shale Formation. Based upon the subsurface soil conditions and the seismic values for Arkansas published by the Arkansas State Building Services, the 1999 Standard Building Code and the 2000 International Building Code the following data are considered applicable to this project site: Site Class (IBC)C* Seismic Zone (ASBS)....................................................... 1 Soil Profile Type (SBC) ................................................... S, Site Coefficient (SBC) ..................................................... 1.0 Peak Acceleration Coefficient (Aa) (ASBS) .................... 0.10 Effective Peak Velocity -Related Acceleration Coefficient (AJ (ASBS) .......................... 0.06 Anderson Engineering Consultants, Inc. Mr. John Burkhalter, P.E. % The Holloway Firm, Inc. Page 3, 09/21/06 CONCLUSIONS Based on the limited field investigation, the following conclusions can be made. The loads exerted by the desired structures will likely require deep foundations. The granular and non- cohesive nature of the soils encountered indicate these soils will likely cave in during deep excavations. Thus, the most likely type of foundation will be auger -cast -in-place (ACIP) piles. Piles are likely the most feasible option in this soil type and can easily provide capacities exceeding 100 kips for a single 14.0 inch pile in dense sand. Based on the limited data obtained, we would anticipate a minimum pile depth of 45.0 feet from existing' grades. Precise pile capacities and depths will require some laboratory testing to obtain the physical properties of the sand and is recommended for a more detailed investigation. Other deep foundation alternatives would be drilled piers or GeoPiers, both of which require an open excavation for concrete or aggregate placement. As stated previously, some cave-ins of the non -cohesive soils is likely. The installation method of the ACIP piles overcomes potential cave-ins and groundwater levels that would hinder the installation of the piers. It is difficult to provide recommendation regarding other construction aspects due to the limited information available at this time. The uncontrolled fill materials will likely require removal from the site to accommodate construction. Locally available fill materials, such as Donnafill, would likely be sufficient for use on the site. We would recommend that fill soils be compacted to a minimum of 95% Modified compaction. LIMITATIONS The boring logs shown in this report contain information related to the types of soil encountered at specific locations and times and show lines delineating the interface between these materials. The logs also contain our driller's interpretation of conditions that are believed to exist in those depth intervals between the actual samples taken. Therefore, these boring logs contain both factual and interpretative information. It is not warranted that these logs are representative of subsurface conditions at other locations and times. The analyses, conclusions, and recommendations contained in this report are based on site conditions as they existed at the time of our field investigation and further on the assumption that the exploratory borings are representative of the subsurface conditions throughout the site. That is, that the subsurface conditions everywhere are not significantly different from those disclosed by the borings at the time they were completed. Since this site has been used as an uncontrolled dump site from a demolition contractor, it will be extremely difficult to determine the condition and content of the rubble present. Anderson Engineering Consultants, Inc. Mr. John Burkhalter, P.E. % The Holloway Firm, Inc. Page 4, 09/21/06 It should also be noted that no grading plans or finished floor elevations were provided at the time of the investigation. Thus, information contained herein is generalized and will not specifically address final elevations. This investigation was primarily performed to determine the condition of the soils/bedrock in an effort to estimate an economical type of foundation that will be required for budgeting purposes. It is strongly recommended that further investigation be performed once site specific plans are developed. It has been a pleasure to have provided this assistance to you and your design team. Please do not hesitate to call with any questions you may have. ANDERSON ENGINEERING J �-4 c3KGNS}LTANiS, INCA 6N®. 73¢. !!ryl!lliIII II 11!111151 SMS/SWA/plf 10835.GEO Very truly yours, ANDERSON ENGINEERING CONSULTANTS, INC. f r - Stuart M. Scheiderer, P.E. Geotechnical Engineer Scott W. Anderson, P.E. Principal Engineer ANDERSON ENGINEERING CONSULTANTS, INC. 10205 ROCKWOOD ROAD, LITTLE ROCK, ARKANSAS 72204 TABL TEXT Important Information About Your Geotechnical Engineering Report .... APPENDIX A Vicinity. Map ............................................... Plan of Borings ........................................... Logs of Borings Field Classification System for Soil Explore Field Identification System for Rocks ........ Key to Soil Classifications and Symbols .... Consolidated Geologic Formations Graphic Unified Soil Classification System (ASTM Ueotecnnical Engineering — Environmental Assessments — uuanty uonzroi UT uonstrucuon iviatenais (-- Geotechnical Engineering Report ---) Geotechnical Services Are Performed for Specific Purposes, Persons, and Protects Geotechnical engineers structure their services to meet the specific needs of their clients. A geotechnical engineering study conducted for a civil engi- neer may not fulfill the needs of a construction contractor or even another civil engineer. Because, each geotechnical engineering study is unique, each geotechnical engineering report is unique, prepared solelyfor the client. No one except you should rely on your geotechnical engineering report without first conferring with the geotechnical engineer who prepared it. And no one — not even you —should apply the report for any purpose or project except the one originally contemplated. Read the Full Report Serious problems have occurred because those relying on a geotechnical engineering report did not read it all. Do not rely on an executive summary. Do not read selected elements only. A Geotechnical Engineeping Reppfmt Is Based on A Unique Set of Protect -Specific Factors Geotechnical engineers consider a number of unique, project -specific fac- tors when establishing the scope of a study. Typical factors include: the client's goals, objectives, and risk management preferences; the general nature of the structure involved, its size, and configuration; the location of the structure on the site; and other planned or existing site improvements, such as access roads, parking lots, and underground utilities. Unless the geotechnical engineer who conducted the study specifically indicates oth- erwise, do not rely on a geotechnical engineering report that was: not prepared for you, not prepared for your project, not prepared for the specific site explored, or completed before important project changes were made. Typical changes that can erode the reliability of an existing geotechhical engineering report include those that affect: m the function of the proposed structure, as when it's changed from a parking garage to an office building, or from a light industrial plant to a refrigerated warehouse, elevation, configuration, location, orientation, or weight of the proposed structure, composition of the design team, or project ownership. As a general rule, always inform your geotechnical engineer of project changes—even minor ones—and request an assessment of their impact. Geotechnical engineers cannot accept responsibility or liability for problems that occur because their reports do not consider developments of which they were not informed. subsurface Conditions Can Change A geotechnical engineering report is based on conditions that existed at . the time the study was performed. Do not rely on a geotechnical engineer- ing reportwhose adequacy may have been affected by: the passage of time; by man-made events, such as construction on or adjacent to the site; or by natural events, such as floods, earthquakes, or groundwater fluctua- tions: Always contact the geotechnical engineer.before applying the report to determine if it is still reliable. A minor amount of additional testing or analysis could prevent major problems. Most Geotechnical Findings Are Professional Opinions Site exploration identifies subsurface conditions only at those,points where subsurface tests are conducted or samples are taken. Geotechnical engi- neers review field and laboratory data and then apply their professional judgment to render an opinion about subsurface conditions throughout the site. Actual subsurface conditions may differ—sometimes significantly— from those indicated in your report. Retaining the geotechnical engineer who developed your report to provide construction observation is the most effective method of managing the risks associated with unanticipated conditions. A Report's Recommendations Are Not Final Do not overrely on the construction recommendations included in your report. Those recommendations are not t<nal, because geotechnical engi- neers develop them principally from judgment and opinion. Geotechnical engineers can finalize their recommendations only by observing actual ANDERSON ENGINEERING CONSULTANTS, INC. 10205 ROCKWOOD ROAD, LITTLE ROCK. ARKANSAS 72204 Geotechnical Engineering — Environmental Assessments — uuaisiy trontrol ur t:onsrrucuorl iviareriais ANDERSON ENGINEERING CONSULTANTS, INC. 10205 ROCKWOOD ROAD, LITTLE ROCK, ARKANSAS 72204 1 NORTH VICINITY MAP LTPTLP ItOCK9 ARKANSAS Geotechnical Engineering - Environmental Assessments - Quality Control Of Construction Materials PLATE 1 PIP cn z z �a N n Z �m <- C) U 00J r J � a Z¢ 0 � 0 ® Y U (J) 0 c W o ® o `+ ALA. ► + s � T r_. 3 0 z PLATE 2 ANDERSON ENGINEERING CONSULTANTS, INC. 10205 ROCKWOOD ROAD, LITTLE ROCK, ARKANSAS 72204 LOG OF BORING PROJECT: PROPOSED RESIDENTIAL DEVELOPMENT BORING NO: B 1 LITTLE ROCK, ARKANSAS FOR: MR. JOHN BURKHALTER LOCATION: SEE PLAN OF BORINGS DATE: 09/08/06 JOB NO: 10835 BORING TYPE: WASH W/SPT/TRICONE DRILLER: JOHNSON GEOTECHNICIAN: JOHNSON GROUND ELEVATION: NOT FURNISHED HILYARD ATV c LEGEND z o ra u0 a S Shelby Tube NX Diamond Core P Penetration Test LL r a T Core ® Standard Penetration m J -Jar N N r n c a g Static Water Table i Hydrostatic Water Table 0 No Recovery C m aj N z 0 F VISUAL DESCRIPTION OF STRATUM 0 P1 50 HARD MOIST BROWN SILT (ML) WITH RUBBLE (FILL) PP = 4.5+ TSF P2 36 PP = 4.5+ TSF P3 11 — APPARENT TOP OF NATURAL GROUND — — — P4 9 MEDIUM DENSE MOIST DARK BROWN SILTY SAND (SM) 10 P5 g LOOSE MOIST DARK BROWN SILTY SAND (SM) P6 20 P7 P8 30—SP9 P10 40 P11 P12 50—S P13 P14 (310-1P15 P16 70 VERY DENSE MOIST BROWN SAND (SP) 50/8" VERY DENSE MOIST BROWN SAND (SP) 50 50 VERY DENSE MOIST BROWN SAND (SP) DENSE MOIST BROWN SAND (SP) 1 39 VERY DENSE MOIST BROWN SAND (SP) 50/8" VERY DENSE MOIST BROWN SAND (SP) 50/7' 50/6" VERY DENSE MOIST BROWN SAND (SP) P17 50/1" HARD WEATHERED GRAY SHALE WITH QUARTZITIC SANDSTONE SEAMS BOTTOM OF HOLE AT 70.5 FEET. BORING REMAINED OPEN. WATER TABLE CANNOT BE VERIFIED DUE TO WASH DRILL METHOD. Geotechnical Engineering®Envlronmental Assessments—Quality Control Of Construction Materials PL ATE 3 4 VERY DENSE MOIST BROWN SAND (Sr) WITH GRAVEL 50 50/11" d•'n VERY DENSE MOIST BROWN SAND (SP) WITH GRAVEL ::P" VERY DENSE MOIST BROWN SAND (SP) WITH GRAVEL 50 BEGIN TRICONE 50/2" k--, HARD WEATHERED GRAY SHALE WITH QUARTZITIC SANDSTONE SEAMS P17 50/1" HARD WEATHERED GRAY SHALE WITH QUARTZITIC SANDSTONE SEAMS BOTTOM OF HOLE AT 70.5 FEET. BORING REMAINED OPEN. WATER TABLE CANNOT BE VERIFIED DUE TO WASH DRILL METHOD. Geotechnical Engineering®Envlronmental Assessments—Quality Control Of Construction Materials PL ATE 3 ANDERSON ENGINEERING CONSULTANTS, INC. 10205 ROCKWOOD ROAD, LITTLE ROCK, ARKANSAS 72204 LOG OF BORING PROJECT: PROPOSED RESIDENTIAL DEVELOPMENT BORING N0: B2 LITTLE ROCK, ARKANSAS FOR: MR. JOHN BURKHALTER LOCATION: SEE PLAN OF BORINGS DATE: 09/08/06 JOB NO: 10835 BORING TYPE: WASH W/SPT/TRICONE DRILLER: JOHNSON GEOTECHNICIAN: JOHNSON GROUND ELEVATION: NOT FURNISHED HILYARD ATV 6c LEGEND w LLc S Shelby Tube NX Diamond Core P Penetration Test L T a to I Core ® Standard Penetration m J -Jar rn L o S Static Water Table Hydrostatic Water Table No Recovery a a E m C a)z coVISUAL DESCRIPTION OF STRATUM D U)P1 50/6" HARD MOIST BROWN SILT (ML) WITH RUBBLE (FILL) PP = 4.5+ TSF P2 50 1 PP = 4.5+ TSF P3 11 STIFF MOIST BROWN SILT (ML) WITH RUBBLE (FILL) PP = 1.25 TSF P4 13 _ — APPARENT TOP OF NATURAL GROUND 10 P5 13 ''' . MEDIUM DENSE MOIST DARK BROWN SILTY SAND (SM) P6 20 P7 P8 30 P9 P10 40—jP11 P12 50-18 P13 P14 60-1P15 P16 70 47 DENSE MOIST BROWN SAND (SP) 50/11" VERY DENSE MOIST BROWN SAND (SP) P17 50/1" ''f" - HARD WEATHERED GRAY SHALE WITH QUARTZITIC SANDSTONE SEAMS BOTTOM OF HOLE AT 70.5 FEET. BORING REMAINED OPEN. WATER TABLE CANNOT BE VERIFIED DUE TO WASH DRILL METHOD - Geotechnical Engineering—Environmental Assessments®®uallty Control Of Construction Materials PLATE 4 VERY DENSE MOIST BROWN SAND (SP) 50 VERY DENSE MOIST BROWN SAND (SP) 50 VERY DENSE MOIST BROWN SAND (SP) 50/10" VERY DENSE MOIST BROWN SAND (SP) 50/8" '` 50/10" a` VERY DENSE MOIST BROWN SAND (SP) WITH GRAVEL VERY DENSE MOIST BROWN SAND (SP) WITH GRAVEL 50/10" 50/11"' VERY DENSE MOIST BROWN SAND (SP) WITH GRAVEL VERY DENSE MOIST BROWN SAND (SP) WITH GRAVEL 50/9.. BEGIN TRICONE 50/1" -a N�•N HARD WEATHERED GRAY SHALE WITH QUARTZITIC SANDSTONE SEAMS P17 50/1" ''f" - HARD WEATHERED GRAY SHALE WITH QUARTZITIC SANDSTONE SEAMS BOTTOM OF HOLE AT 70.5 FEET. BORING REMAINED OPEN. WATER TABLE CANNOT BE VERIFIED DUE TO WASH DRILL METHOD - Geotechnical Engineering—Environmental Assessments®®uallty Control Of Construction Materials PLATE 4 ANDERSON ENGINEERING CONSULTANTS, INC. 10205 ROCKWOOD ROAD, LITTLE ROCK, ARKANSAS 72204 FIELD CLASSIFICATION SYSTEM FOR SOIL EXPLORATION NON COHESIVE SOILS (Silt, Sand, Gravel and Combinations) Density Very Loose - 0 - 4 blows/305 mm Loose - 4 to 10 blows/305 mm Medium Dense - 10 to 30 blows/305 mm Dense - 30 to 50 blows/305 nun Very Dense - over 50 Relative Proportions Descriptive Term Percent Trace 1-10 Little 11-20 Some 21-35 And 36-50 Particle Size Identification Boulders - 203 mm diameter or more Cobbles - 76 to 203 mm diameter Gravel - Coarse - 25 to 76 mm Medium - 13 to 25 mm Fine - 6 to 13 mm Sand - Coarse - 0.6 to 6 mm Plastici (dia. of pencil lead) Medium - 0.2 mm to 0.6 mm None to slight (dia. of broom straw) Fine - 0.05 mm to 0.2 mm Slight (dia. of human hair) Silt - 0.06 mm to 0.002 mm Medium (Cannot see particles) COHESIVE SOILS (Clay, Silt and Combinations) Consistency Plasticily Very Soft - <2 blows/305 mm Degree of Plasties Soft - 2 to 4 blows/305 mm Plastici Index Medium Stiff - 4 to 8 blows/305 mm None to slight 0 - 4 Stiff - 8 to 15 blows/305 mm Slight 5 - 7 Very Stiff - 15 to 30 blows/305 mm Medium 8-22 Hard - over 30 High to Very High over 22 NOTES Classification on logs are made by visual inspection. Standard Penetration Test - Driving a 51 mm O.D., 35 mm I.D., sampler a distance of 305 mm into undisturbed soil with a 63.5 kilogram hammer free falling a distance of 762 mm. It is customary for AECI to drive the spoon 152 mm to seat into undisturbed soil, then perform the test. The number of hammer blows for seating the spoon and making the tests are recorded for each 152 mm of penetration on the drill log (Example: 6/8/9). The standard penetration test results can be obtained by adding the last two figures (i.e., 8 + 9 = 17 blows/305 mm). Strata Changes - In the column "Soil Descriptions" on the drill log the horizontal lines represent strata changes. A solid line (------) represents an actually observed change, a dashed line (- - - -) represents an estimated change. Groundwater observations were made at the times indicated. Porosity of soil strata, weather conditions, site topography, etc., may cause changes in the water levels indicated on the logs. Geotechnical Engineering m Environmental Assessments — Quality Control Of Construction Materials J PLATE 5 ANDERSON ENGINEERING CONSULTANTS, INC. 10205 ROCKWOOD ROAD, LITTLE ROCK, ARKANSAS 72204 FIELD IDENTIFICATION SYSTEM FOR ROCKS CLASSIFICATION NAME 4jCRS IPTIOtL CALCIUM CARBONATE coca LIMESTONE Light to dark colored, crystalline to lino -grained s texture, composed of CoCO , reads with NCI. DOLOMITE Light to dark colored, crystalline to fine-grained texture, composed of MgCO', slightly harder than ra IIMff1oN1 limestone, reads to HCI when powdered. CHERT Light to dark colored, smooth very fine-grained 11JUM MMT texture, composed of .micro -crystalline quartz UMffTOW UNA ONII (Si0 ), brittle, breaks Into angular fragments, will so scratch plass. SHALE Usually dark colored, very fine-grained texture, UMT IAN"Tow My INNS composed of consolidated mud, silt, or clay, 9S usually beddad in thin layen. The unlaminated equivalent is frequently referred to as Ontario, flMlt• •/ANefTOw f�NaY fNAlf daystone, or mudstone. SAND 9:1 1:1 1:0 SILT or SANDSTONE Usually light colored, coarse to fine texture, com- RATIO OF SAND TO SILT AND WY CLAY posed of cemented sand size grains of quartz, feldspar, etc. PHYSICAL PROPERTIES LIDDING CHARACTERISTICS HARDNESS AND DEGREE QF CEMENTATION IBM THICKNESS LIMESTONE HARD — Difficult to scratch with knife. VERY THICK BEDDED >3' >100 THICK BEDDED V.3' 30.100 MEDIUM BEDDED 4"-1' 10.30 THIN BEDDED 1"-4" 3-10 VERY THIN BEDDED 0.4"-1" 1-3 LAMINATED 0.1"-0.4" 0.3-1 THINLY LAMINATED <0.1" <0.3 MODERATELY HARD —Can be scratched easily with knife, cannot be scratched with fingernail. SOFT — Can be scratched with fings mail. SHALE HARD — Can be scratched easily with knife, can- not be scratched with fingernail. MODERATELY HARD — Can be scratched with fingernail. SOFT — Can be easily molded with fingers. BEDDING PLANES Planes dividing sedimentary rocks of the same or different lithology. JOINT Fracture in rock, generally more or less vortical or fronsvarse to the bedding. SEAM Generally applies to bedding plane with an un- specified degree of weathering. GRAIN SIZE x015 1 a�0 41* SANDSTONE WELL CEMENTED — Capable of scratching a knife blade. CEMENTED — Can be hKralched with knife. POORLY CEMENTED — Can be broken apart easily with fingers. L]EGREE OF WEATHERING SLIGHTLY WEATHERED Slight decomposition of parent material In joints and seams. WEATHERED Well developed and decomposed joints and seams. HIGHLY WEATHERED Rads highly decomposed, may lbs oxtiemely broken. SOLUTION AND VOID CONDITIONS A '}� ! }.•p ■eiiiiii S•� n I ■:iie�� i�'%•� esiie0i SOLID VUGGY (Pitted) Contains no voids Rock having small solution pits or cavities up to sash■■ sasses inch diameter, frequently with a mineral T ease � lining. ! ! • ■ i 00000 !!!!a s POROUS Containing numerous voids, pores, or other 0 openings, which may or may not interconnect. 00 i !rr ti CAVERNOUS Containing cavities or caverns, sometimes large. aquite slop O 000. Geotechnical Engineering m Environmental Assessments - Quality Control Of Construction Materials PLATE 6 ANDERSON ENGINEERING CONSULTANTS, INC. 10205 ROCKWOOD ROAD, LITTLE ROCK, ARKANSAS 72204 KEY TO SOIL CLASSIFIQ UNIFIED SOIL CLASSIFICATION SYSTEM( Symbol Major Divisions Letter Name Hatching Color oo"I � o; Well -graded gravels or gr GW o ns mixtures, little or no fines o W Poorly -graded gravels or of GRAVEL GP �.' mixtures, little or no fines AND GRAVELLY SOILS GM 0 O Silty gravels, gravel -sand W } Clayey gravels, gravel-sa COARSE GC mixtures GRAINED SOILS o o o Well -graded sands or gra SW o o o little or no fines o p W Poorly -graded sands or g • •� SAND SP little or no fines AND SANDY SOILS SM Silty sands, sand -silt mixt O Clayey sands, sand -clay SC WW } Inorganic silts and very fii ML flour, silty or clayey fine s silts with slight plasticity SILTS z Inorganic clays of low to i ANDCIL w plasticity, gravelly clays, ((9 silty Gays, lean clays LL<50 I I I Organic silts and organic FINE OIL 1 low plasticity GRAINED Inorganic silts, micaceous SOILS MH diatomaceous fine sandy soils, elastic silts SILTS AND10W Inorganic clays of high pl CLAYS CH m fat clays LL>50 Organic clays of medium OH plasticity, organic silts HIGHLY w ORGANIC Pt z Peat and other highly org SOILS o TERMS DESCRIBING CON COARSE GRAINED SOILS DESCRIPTIVE TERM NO. BLOWS/FOOT DESCRIPTIVE STANDARD PEN. TEST Very Soft Very Loose 0-4 Soft Loose 4-10 Plastic (mediun Firm (medium dense) 10-30 Stiff Dense 30-50 Very Stiff Very Dense over 50 _I Hard Field classification for "Consistency" is determined with a 0.25 -inch diameter pe (1) - From Waterways Experiment Station Technical Memorandum No. 3-357 (2) - From "Soil Mechanics in Engineering Practice" by Terzaghi and Peck Geotechnical Engineering - Environmental Assessments — uumity t,v"uvr yr vvneruucsrvn MULU19UND ___J PLATE 7 ANDERSON ENGINEERING CONSULTANTS, INC. 10205 ROCKWOOD ROAD, LITTLE ROCK, ARKANSAS 72204 CONSOLIDATED GEOLOGIC FORMATIONS GRAPHIC LOG SYMBOLS SEDIMENTARY ROCKS SHALE SHALE SANDSTONE (WEA THERED) `L L IMESTONE (WEATHERED) SLATE L /MES TONE (CAVERNOUS) c3 a o � o � C= O, C � O a LIMESTONE (CHERTY) .0 °' 'Q: •br.'9 - P. o•0'•p ID. •p e• :0�.a .: COWGLOMERA TE BRECCIA METAMORPHIC ROCKS QUARTZITE IGNEOUS ti�►.,.�� r:f.rr. GRAN/TE ROCKS gip, o PORPHYRY SANDSTONE (WEA THERED) MODIFICATION OF THESE FORMATIONS CAN BE SHOWN BY A COMBINATION OF SVM6OLS Geotechnical Engineering - Environmental Assessments - Quality Control Of Construction Materials PLATE 8 ANDERSON ENGINEERING CONSULTANTS, INC. 10205 ROCKWOOD ROAD, LITTLE ROCK, ARKANSAS 72204 UNIFIED SOIL CLASSI (ASTM D Major divisions Group Typical Names Symbols GW Well -graded gravels, gravel -sand H little or no fines ymixtures, c o V m v v GP Poorly graded gravels, gravel - sand mixtures, little or no fines q m O 2 Silly gravels, gravel -sand -silt c m L E mixtures d Z E 3 u c w `a ti C o a " $ GC Clayey gravels, gravel -sand -clay mixtures ka u'-ce- m SW Well -graded sands, gravelly sands, v E H little or no fines e z.- m c E m SP Poorly graded sands, gravelly sands, little or no fines � d Silly sands, sand -silt matures u m nc m m O C m YJ n SC Clayey sands, sand -day matures n Q Inorganic sifts and very fine sands, c ML rock flour, silly or clayey fine sands, C or clayey sifts with slight plasticity v �+ q Inorganic clays of low to medium > c m CL plasticity, gravelly clays, sandy o Gays, silly clays, lean clays N Co k :2 7 z° [T `'' OL Organic silts and organic silty clays r of low plasticity Vl ~ O m E Inorganic sifts, micaceous or c H o MH dlatomaceous fine sandy or '� ko silly soils, elastic silts LLS CH Inorganic clays of high plasticity, fat m clays r _m =' •E m S v � OH Organic clays of medium to high plasticity, organic silts'F oE Pt Peat and other highly organic soils "Division of GM and SM groups into subdivisions of d and u are for roads and airfield only suffix d used when L.L. is 26 or less and the P.I. Is 6 or less; u used when L.L Is greater U -Borderline classifications, used for soils possessing characteristics of two groups, are de For example GW -GC, well -graded gravel -sand mature with clay binder. em. ®ot®®h. — EnMln®®Iring m E.. I—mental Assesamb,,.� eRY 61lly MUNISIVO @ 1 a %J190%1UU&eve1 MOLOreara PLATE 9