DCPL-2016-R-0024 Attachments J.14
Transcription
DCPL-2016-R-0024 Attachments J.14
Preliminary Geotechnical Engineering Study DCPL – Capitol View Branch Library Washington, D.C. HCEA Job No. 14465A Prepared for: Smoot Construction Company 5335 Wisconsin Avenue, NW Washington, DC 20015 HILLIS-CARNES ENGINEERING ASSOCIATES, INC. Post Office Box 241 Annapolis Junction, MD 20701 February 4, 2015 Baltimore 410-880-4788 DC Metro 301-470-4239 Smoot Construction Company 5335 Wisconsin Avenue, NW Washington, DC 20015 Fax 410-880-4098 www.hcea.com Attention: Mr. Stuart M. Dziura Re: Preliminary Geotechnical Engineering Study DCPL – Capitol View Branch Library Washington, D.C. HCEA Job No. 14465A Gentlemen: Hillis-Carnes Engineering Associates, Inc. (HCEA) is pleased to submit this report concerning the preliminary subsurface exploration and subsequent preliminary geotechnical evaluation for the proposed library construction that is to be located in Washington, D.C. We wish to advise you that the boring samples will be stored at our Annapolis Junction, Maryland office for a period of 30 days from the date of this letter. Should you wish the samples to be stored for a longer period of time or to be delivered to you or another party, please advise us in writing prior to the end of the 30-day period. Otherwise, the samples will be discarded at the end of the 30-day storage period. HCEA appreciates having had the opportunity to provide the geotechnical consultation for this project, and we will remain available for further consultation during the various design stages. In order to provide complete professional services, we strongly recommend that inspection of the geotechnical aspects of construction be conducted by HCEA. This will help to verify that the construction operations are performed in accordance with the design recommendations of this report and the overall project plans and specifications. Should you have any questions concerning the contents of this report, or require additional consultation, design, inspection, or testing services, please contact our Office. Very truly yours, HILLIS-CARNES ENGINEERING ASSOCIATES, INC. Michael P. Johnson, P.E. Timothy B. Hill, P.E. HILLIS-CARNES ENGINEERING ASSOCIATES, INC. ENGINEERING ASSOCIATES, INC. 10975 Guilford Road, Suite A TABLE OF CONTENTS LETTER OF TRANSMITTAL ...................................................................................................i 1.0 PURPOSE AND SCOPE ................................................................................................ 1 2.0 PROJECT CHARACTERISTICS.................................................................................... 1 3.0 FIELD EXPLORATION ................................................................................................... 2 4.0 SUBSURFACE CONDITIONS ....................................................................................... 2 4.1 Man-Placed Fill Materials ................................................................................ 3 4.2 Natural Materials.............................................................................................. 3 4.3 Groundwater .................................................................................................... 3 5.0 PRELIMINARY EVALUATIONS AND RECOMMENDATIONS .................................... 4 5.1 General Site Preparation ................................................................................. 4 5.2 Fill Selection, Placement and Compaction ..................................................... 5 5.3 Foundation Evaluations ................................................................................... 5 5.4 Ground-Supported Slabs................................................................................. 6 5.5 Groundwater and Drainage ............................................................................. 6 6.0 REMARKS ...................................................................................................................... 7 APPENDIX ............................................................................................................................. 9 HILLIS-CARNES ENGINEERING ASSOCIATES, INC. PRELIMINARY GEOTECHNICAL ENGINEERING STUDY DCPL – CAPITOL VIEW BRANCH LIBRARY WASHINGTON, D.C. HCEA JOB NO. 14465A 1.0 PURPOSE AND SCOPE The purpose of this study was to preliminarily determine the general subsurface conditions at the boring locations and to preliminarily evaluate those conditions with respect to concept and design of foundation systems and floor slabs for the proposed construction. The preliminary evaluations and recommendations presented in this report were developed from an analysis of project characteristics and an interpretation of the general subsurface conditions at the site based on the boring information. The stratification lines indicated on the boring logs represent the approximate boundaries between soil types. In-situ, however, the transitions may be gradual. Such variations can best be evaluated during construction and, if necessary, any minor design changes can be made at that time. An evaluation of recommendations are also included. conditions and to properly. the site with respect to potential construction problems and dealing with the earthwork and inspection during construction The inspection is considered necessary to verify the subsurface verify that the soils-related construction phases are performed The Appendix contains a summary of the field work on which this report is based. 2.0 PROJECT CHARACTERISTICS The project site is located at 5001 Central Avenue, SE in Washington D.C. as shown on the Project Location Map (Figure 1) in the Appendix. Based on information provided by the Client, we understand that the proposed construction at the site is to include is to include a new library building. The site is currently occupied by an existing library structure that is to be removed prior to the initiation of new construction. Additional details concerning the proposed construction were not available at the time that this report was being prepared. Should any of the project characteristics differ from those outlined above, then this office should be contacted for a reevaluation of the site. HILLIS-CARNES ENGINEERING ASSOCIATES, INC. DCPL – CAPITOL VIEW BRANCH LIBRARY Preliminary Geotechnical Engineering Study 3.0 FIELD EXPLORATION In order to determine the general foundation soil types and to develop preliminary design parameters, five Standard Penetration Test (SPT) soil borings were drilled to depths of 45 ft below existing site grades in accessible locations at the site. We understand that additional borings are to be drilled once the existing structure is demolished and removed to confirm the subsurface conditions in currently inaccessible areas of the site. The boring locations were located in the field by HCEA by estimation from existing site features. Therefore, the boring locations shown on the Boring Location Plan (Figure 2) in the Appendix should be considered approximate. The borings were advanced with hollow-stem augers and the subsurface soils were sampled at 2.5 ft and 5.0 ft intervals. Samples were taken by driving a 1-3/8 inch I.D. (2-inch O.D.) split-spoon sampler in accordance with ASTM D-1586 specifications. The sampler was first seated 6 inches to penetrate any loose cuttings and then was driven an additional foot with blows of a 140 pound hammer falling 30 inches. The number of hammer blows required to drive the sampler the final foot is designated as the "Penetration Resistance" or "N" value. The penetration resistance, when properly evaluated, is an index to the soil strength and compression characteristics. Representative portions of each soil sample were placed in glass jars and transported to HCEA's laboratory. In the laboratory, the samples were visually examined by the Geotechnical Engineer to verify the driller's field classifications. The samples were visually classified in general accordance with the Unified Soil Classification System and the field classifications were revised where necessary. The Unified Soil Classification Symbols appear on the Boring Logs and the system nomenclature is briefly described in the Appendix. 4.0 SUBSURFACE CONDITIONS Details of the subsurface conditions encountered at the site are shown on the Records of Soil Exploration. A brief description of the subsurface conditions and pertinent engineering characteristics of the soils are given below. Strata divisions shown on the Records of Soil Exploration have been estimated based on visual examinations of the recovered boring samples. In the field, strata changes could occur gradually and/or at slightly different levels than indicated. Also, groundwater conditions indicated on the Records of Soil Exploration are those observed during the period of the subsurface exploration. Fluctuations in groundwater levels could occur seasonally and might also be influenced by changes in grading, runoff and infiltration rates, and other influencing factors. HILLIS-CARNES ENGINEERING ASSOCIATES, INC. 2 DCPL – CAPITOL VIEW BRANCH LIBRARY Preliminary Geotechnical Engineering Study Generalized subsurface conditions based on the results of the borings are discussed below: 4.1 Man-Placed Fill Materials Materials specifically identified as man-placed fill materials or possible manplaced fill materials were encountered at the following locations in the borings: Approximate Depth Boring of Fill Material (ft) B-1 B-2 B-3 B-4 B-5 18.5 17.0 18.0 18.5 17.0 Since the size of the samples obtained is relatively small in comparison to the areal extent of the site and since the fill materials could be of similar composition to the natural soils encountered at the site, it is often difficult to determine the presence and composition of fill materials from the SPT samples. It should be anticipated that man-placed fill materials may be encountered at other locations and to different depths across the site due to the previous construction that has occurred on and around the project site. 4.2 Natural Materials The natural soils encountered at the site were visually classified in general accordance with the Unified Soil Classification System as silty sand (SM) and silty or sandy clay (CL or CH). "N" values from the Standard Penetration Test (SPT) borings typically indicated relative densities in the dense to very dense range for the more granular natural materials encountered. The more fine-grained materials typically exhibited consistencies in the very stiff to hard range. 4.3 Groundwater Groundwater levels were monitored in the open boreholes. The shallowest groundwater encountered in the borings was located at a depth of 25.5+ ft below existing site grades in the caved borehole at the location of Boring B-5. Water that appeared to be perched within the existing fill materials was encountered at a depth of 8.5+ ft in Boring B-4 and at a depth of 5.5+ ft in Boring B-5. HILLIS-CARNES ENGINEERING ASSOCIATES, INC. 3 DCPL – CAPITOL VIEW BRANCH LIBRARY Preliminary Geotechnical Engineering Study A more accurate determination of the hydrostatic water table would require the installation of perforated pipes or piezometers which could be monitored over an extended period of time. The actual level of the hydrostatic water table and the amount and level of perched water should be anticipated to fluctuate throughout the year, depending on variations in precipitation, surface run-off, infiltration, site topography, and drainage. It should also be anticipated that perched water will be encountered in pockets within the fill materials or at the interface of fill materials and natural soils. 5.0 PRELIMINARY EVALUATIONS AND RECOMMENDATIONS Our findings indicate that the site can be developed for the proposed structure utilizing conventional spread footings and ground-supported slab construction. The presence of relatively soft and loose existing fill/possible fill materials to estimated depths of 17+ ft to 18.5+ ft below existing site grades will have a significant impact on construction operations. Footings should not be constructed on or over any existing fill materials. It is recommended that the proposed structure be supported on a deep foundation system consisting of either augered, cast-in-place concrete piles or drilled shafts. Alternatively, it may be possible to utilize alternative subgrade modification techniques (such as rammed-aggregate piers) in order to provide a shallow foundation alternative for the structure. The following preliminary recommendations have been developed on the basis of the previously described project characteristics and subsurface conditions. If there are any changes to the project characteristics or if different subsurface conditions are encountered during construction, HCEA should be consulted so that the recommendations of this report can be reviewed and revised, if necessary. 5.1 General Site Preparation All existing structures (including all above and below ground construction) within the areas to be developed should be removed prior to the initiation of new construction. We suggest that all available information regarding the existing utilities at the site be reviewed prior to construction. Removal should include all underground pipes, utilities, and underground structures that might interfere with the new construction. If abandoned underground utilities are to be removed prior to the initiation of construction, provisions should be made in the construction specifications and budget to restore the subgrade to stable condition. Restoration should include backfilling and compaction of the excavation areas. After the initial stripping process is completed, areas of the site to receive fill, or areas of the site at-grade where structures will be located, should be proofrolled. The proofrolling operations should be performed using a 20-ton, fully-loaded dump truck or another pneumatic-tire vehicle of similar size and HILLIS-CARNES ENGINEERING ASSOCIATES, INC. 4 DCPL – CAPITOL VIEW BRANCH LIBRARY Preliminary Geotechnical Engineering Study weight. The purpose of the proofrolling will be to locate any near-surface pockets of soft or loose soils requiring undercutting. A Geotechnical Engineer or experienced Soils Inspector should witness the proofrolling operations and should determine which areas need further undercutting and/or stabilization. 5.2 Fill Selection, Placement and Compaction All material to be used as fill or backfill should be inspected, tested and approved by the Geotechnical Engineer. In general, the on-site soils which are free from organic and other deleterious components can be re-used as general site fill. Materials suitable for various construction purposes can be identified by an experienced Soils Inspector during grading operations. Moisture conditioning (that is, wetting or drying) of the soils should be anticipated to achieve proper compaction. The moisture contents of the soils should be controlled properly to avoid extensive construction delays. If imported fill material is required, those materials should have Unified Soil Classifications of SM or better. All fill should be placed in relatively horizontal 8-inch (maximum) loose lifts and should be compacted to a minimum of 95 percent of the Standard Proctor (ASTM D-698) maximum dry density. Fill materials in landscape and other non-structural areas should be compacted to at least 90 percent of the Standard Proctor maximum dry density if significant subsidence of the fill under its own weight is to be avoided. Field moisture contents should be maintained within 2 percentage points of the optimum moisture content in order to provide adequate compaction. Structural fill should extend a minimum of ten feet beyond building lines where floor slabs are to be constructed on the fill. Fill slopes no steeper than 2(H):1(V), or flatter, should be used. A sufficient number of in-place density tests should be performed by an experienced Engineering Technician on a full-time basis to verify that the proper degree of compaction is being obtained. 5.3 Foundation Evaluations As stated previously, relatively soft and loose existing fill/possible fill materials were encountered to estimated depths of 17+ ft to 18.5+ ft below existing site grades at the site. As such, foundations for the proposed structure will require special consideration. Footings should not be placed on or over any existing fill materials. Footings should not be constructed on or over any existing fill materials. As such, it is recommended that the proposed structure be supported on a HILLIS-CARNES ENGINEERING ASSOCIATES, INC. 5 DCPL – CAPITOL VIEW BRANCH LIBRARY Preliminary Geotechnical Engineering Study deep foundation system consisting of either augered, cast-in-place concrete piles or drilled shafts. Alternatively, it may be possible to utilize alternative subgrade modification techniques (such as rammed-aggregate piers) in order to provide a shallow foundation alternative for the structure. It is recommended that the additional borings (that are to be drilled during the final study once the existing structure has been removed) be drilled to greater depths below existing site grades to be able to better evaluate the most economical foundation system for the structure. 5.4 Ground-Supported Slabs Floor slabs should be supported on approved, firm natural soils, or on new compacted fill. The slab subgrade should be prepared in accordance with the procedures outlined in Sections 5.1 and 5.2 of this report. In particular, the slab subgrade should be heavily proofrolled to delineate any soft or loose areas requiring undercutting and/or stabilization. Since relatively soft/loose fill materials were encountered in the borings drilled during this study, additional slab subgrade evaluation will be required during the final study. It should be anticipated that the modification of slab subgrade materials will be required at a minimum. Structurally supporting the slab may also need to be considered. It is recommended that the slab be directly supported on a minimum 4-inch layer of clean granular materials such as washed sand, clean sand and gravel, or screened, crushed stone. These materials will require acquisition from an off-site source. A suitable moisture/vapor barrier (that is, polyethylene sheeting) should also be provided. These procedures will provide a moisture break that will help to prevent capillary rise, dampness of the floor slabs and also help to cure the slab concrete. It is also recommend that construction joints on the slab surface and isolation joints between the slab and structural walls be provided (such that the slab would be groundsupported). On most projects, there is a significant time lag between initial grading and a point when the contractor is ready to pour the slabs-on-grade. Environmental conditions and construction traffic often disturb the subgrade soils. Provisions should be made in the construction specifications for the restoration of the subgrade soils to a stable condition prior to the placement of the concrete for the floor slabs. 5.5 Groundwater and Drainage Groundwater levels were monitored in the open boreholes. The shallowest groundwater encountered in the borings was located at a depth of 25.5+ ft below existing site grades in the caved borehole at the location of Boring B-5. Water that appeared to be perched within the existing fill materials HILLIS-CARNES ENGINEERING ASSOCIATES, INC. 6 DCPL – CAPITOL VIEW BRANCH LIBRARY Preliminary Geotechnical Engineering Study was encountered at a depth of 8.5+ ft in Boring B-4 and at a depth of 5.5+ ft in Boring B-5. It should be anticipated that additional water or perched water will be encountered at varying depths across the site. The magnitude of the impact of the water on construction will be dependent on the foundation and slab alternatives selected. Adequate drainage should be provided at the site to minimize any increases in the moisture contents of the foundation soils. All pavement or parking areas should be sloped away from the structure to prevent the ponding of water around the building. The site drainage should also be such that run-off onto adjacent properties is controlled properly. 6.0 REMARKS This report has been prepared to aid in the evaluation of the site for the proposed library construction. It is considered that adequate recommendations have been provided to serve as a basis for preliminary site evaluation. Additional recommendations can be provided as needed. These preliminary analyses and recommendations are, of necessity, based on the information made available to us at the time of the actual writing of the report and the on-site conditions, surface and subsurface, that existed at the time the exploratory borings were drilled. Further assumption has been made that the limited exploratory borings, in relation both to the areal extent of the site and to depth, are representative of conditions across the site. If subsurface conditions are encountered which differ from those reported herein, this Office should be notified immediately so that the analyses and recommendations can be reviewed and/or revised as necessary. It is also recommended that: 1. We be given the opportunity to review any plans and specifications in order to comment on the interaction of the soil conditions as described herein and the design requirements. 2. A Geotechnical Engineer or experienced Soils Inspector be present at the site during the construction phase to verify installation according to the approved plans and specifications. This is particularly important during excavation, placement, and compaction of fill materials. Please note that successful completion of the project is dependent on your compliance with all of the recommendations provided in this report. While represented separately, the recommendations represent work that is intertwined. The successful completion of the project is specifically conditioned on your complying with all recommendations. HILLIS-CARNES ENGINEERING ASSOCIATES, INC. 7 DCPL – CAPITOL VIEW BRANCH LIBRARY Preliminary Geotechnical Engineering Study Our professional services have been performed, our findings obtained, and our recommendations prepared in accordance with generally accepted engineering principles and practices. This warranty is in lieu of all other warranties either implied or expressed. Hillis-Carnes Engineering Associates, Inc. assumes no responsibility for interpretations made by others based on work or recommendations made by HCEA. HILLIS-CARNES ENGINEERING ASSOCIATES, INC. 8 DCPL – CAPITOL VIEW BRANCH LIBRARY Preliminary Geotechnical Engineering Study APPENDIX Figure 1: Project Location Map Figure 2: Boring Location Plan Subsurface Profile Particle Size Distribution Reports Records of Soil Exploration Field Classification Sheet HILLIS-CARNES ENGINEERING ASSOCIATES, INC. 9 HILLIS-CARNES ENGINEERING ASSOCIATES, INC. PROJECT LOCATION MAP Scale: Reduced Figure: 1 B-2 B-4 B-3 B-5 B-1 LEGEND: SOIL BORING LOCATION BORING LOCATION PLAN DCPL - CAPITOL VIEW BRANCH LIBRARY 10975 Guilford Road, Suite A Annapolis Junction, Maryland (410) 880-4788 WWW.HCEA.COM Fax: (410) 880-4098 5001 CENTRAL AVE, SE WASHINGTON, DC 14465A 11/24/14 1" = 40' 1 WH AM MPJ LOG OF BORINGS DCPL Capitol View Branch 120 120 B-1 110 B-4 B-3 B-2 7 B-5 8 2 11 10 4 9 12 5 3 4 4 1 5 5 110 3 3 1 16 9 100 100 16 13 2 9 19 16 23 69 21 90 90 24 38 17 34 33 39 17 35 30 30 80 80 66 47 31 37 56 68 91+ 50 85+ 77+ 70 70 81 90 67 86 60 67 60 Fill Description not given for: "O:" Description not given for: "0O" Description not given for: "FE" Description not given for: "OZ" Low-high plasticity clays Low plasticity clay Silty sand HILLIS-CARNES ENGINEERING ASSOCIATES, INC. Elevation in Feet Elevation in Feet 28 #200 #140 #100 #60 #40 #30 #20 #10 #4 3/8 in. ½ in. ¾ in. 1 in. 1½ in. 2 in. 3 in. 6 in. Particle Size Distribution Report 100 90 80 PERCENT FINER 70 60 50 40 30 20 10 0 100 10 1 0.1 0.01 0.001 GRAIN SIZE - mm. % +3" % Gravel % Sand 0.0 0.0 83.7 SIEVE PERCENT SPEC.* PASS? SIZE FINER PERCENT (X=NO) 3" 2" 1 1/2" 1" 3/4" 3/8" #4 #10 #40 #100 #200 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 99.4 30.0 16.3 % Silt % Clay 16.3 Material Description Orange brown silty sand PL= NP Atterberg Limits LL= NP PI= NP D90= 0.3594 D50= 0.2081 D10= Coefficients D85= 0.3332 D30= 0.1500 Cu= USCS= SM Classification AASHTO= A-2-4(0) D60= 0.2381 D15= Cc = Remarks Moisture Content: 6.9% * (no specification provided) Location: B-1, S-9 Sample Number: 1 Date: 01/23/15 Depth: 33.5'-35.0' HILLIS-CARNES ENGINEERING ASSOCIATES, INC. Annapolis Junction, MD Client: Project: DCPL - Capitol View Branch Library Project No: 14465A Figure #200 #140 #100 #60 #40 #30 #20 #10 #4 3/8 in. ½ in. ¾ in. 1 in. 1½ in. 2 in. 3 in. 6 in. Particle Size Distribution Report 100 90 80 PERCENT FINER 70 60 50 40 30 20 10 0 100 10 1 0.1 0.01 0.001 GRAIN SIZE - mm. % +3" % Gravel % Sand 0.0 0.0 0.4 SIEVE PERCENT SPEC.* PASS? SIZE FINER PERCENT (X=NO) 3" 2" 1 1/2" 1" 3/4" 3/8" #4 #10 #40 #100 #200 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 99.9 99.7 99.6 % Silt % Clay 99.6 Material Description Red with brown fat clay PL= 26 Atterberg Limits LL= 64 PI= 38 D90= D50= D10= Coefficients D85= D30= Cu= USCS= CH Classification AASHTO= A-7-6(45) D60= D15= Cc = Remarks Moisture content: 18.4% * (no specification provided) Location: B-3, S-6 Sample Number: 2 Date: 01/23/15 Depth: 18.5'-20.0' HILLIS-CARNES ENGINEERING ASSOCIATES, INC. Annapolis Junction, MD Client: Project: DCPL - Capitol View Branch Library Project No: 14465A Figure HILLIS - CARNES ENGINEERING ASSOCIATES, INC. RECORD OF SOIL EXPLORATION DCPL Capitol View Branch Project Name Washington DC, SE Location MSL Datum Hammer Wt. 112.5 Surf. Elev. ft 12/3/14 Date Started Elevation/ Depth Hammer Drop Pipe Size SOIL SYMBOLS/ SAMPLE CONDITIONS 140 30 2.0 Description B-1 Boring No. 14465A Job # SAMPLER lbs. Hole Diameter 6" in. Rock Core Diameter in. Boring Method Boring and Sampling Notes N/A HSA Rec. NM% Foreman M. Stawas Inspector W. Harris 1/2/15 Date Completed SPT Blows N SPT Blows/Foot Curve 10 16" 3-4-3 7 15" 4-3-2 5 18" 2-1-2 3 Mottled Light Gray/Dark RedBrown/Orange-Brown, moist, very stiff CLAY with fine sand (CL) Possible Fill 18" 3-7-9 16 Mottled Brown/Orange-Brown/Dark Gray, moist, very stiff SILT with clay and sand (ML) Possible Fill 7" 5-7-9 16 I Light Brown, moist, very stiff CLAY with silt, trace sand (CL) 18" 8-11-17 28 I Gray with Yellow-Brown, moist, very stiff sandy CLAY (CL) 18" 5-10-14 24 I Brown/Gray, moist, very stiff silty CLAY with sand (CL) 18" 7-12-18 30 Light Red-Brown to Gray, moist, 18" 16-30-36 66 I 110 I 5 I Orange-Brown, moist, loose clayey SAND with gravel. (SC) Possible Fill Gray/Orange-Brown, moist, soft CLAY with sand and organics (CL) Possible Fill Light Brown, moist, soft CLAY with silt and trace sand (CL) Possible Fill 3" of Asphalt 2" of Stone 30 50 105 I 10 100 I 15 95 20 90 25 85 30 80 I SAMPLER TYPE DRIVEN SPLIT SPOON UNLESS OTHERWISE SAMPLE CONDITIONS D - DISINTEGRATED AT COMPLETION GROUND WATER ft. Dry CAVE IN DEPTH 33.5 ft. BORING METHOD HSA - HOLLOW STEM AUGERS 66 PT - PRESSED SHELBY TUBE I - INTACT AFTER 24 HRS. ft. ft. CFA - CONTINUOUS FLIGHT AUGERS CA - CONTINUOUS FLIGHT AUGER U - UNDISTURBED AFTER ft. ft. DC - DRIVING CASING RC - ROCK CORE L - LOST HRS. MD - MUD DRILLING STANDARD PENETRATION TEST-DRIVING 2" O.D. SAMPLER 1' WITH 140# HAMMER FALLING 30": COUNT MADE AT 6" INTERVALS. HILLIS - CARNES ENGINEERING ASSOCIATES, INC. RECORD OF SOIL EXPLORATION DCPL Capitol View Branch Project Name Washington DC, SE Location MSL Datum 112.5 Surf. Elev. ft 12/3/14 Date Started Elevation/ Depth 140 Hammer Wt. 30 Hammer Drop Pipe Size SOIL SYMBOLS/ SAMPLE CONDITIONS 2.0 Description B-1 Boring No. 14465A Job # SAMPLER lbs. Hole Diameter 6" in. Rock Core Diameter in. Boring Method Boring and Sampling Notes N/A HSA Rec. NM% Foreman M. Stawas Inspector W. Harris 1/2/15 Date Completed SPT Blows N SPT Blows/Foot Curve 10 30 50 very dense silty SAND (SM) 35 75 Groundwater encountered at 38.5 while drilling I 40 17" 17-35-50/5" 85+ 85+ 18" 18-37-44 81 81 70 I 45 Bottom of boring at 45 ft Boring backfilled with grout and patched at completion 65 50 60 55 55 60 50 65 45 SAMPLER TYPE DRIVEN SPLIT SPOON UNLESS OTHERWISE SAMPLE CONDITIONS D - DISINTEGRATED AT COMPLETION GROUND WATER ft. Dry CAVE IN DEPTH 33.5 ft. BORING METHOD HSA - HOLLOW STEM AUGERS PT - PRESSED SHELBY TUBE I - INTACT AFTER 24 HRS. ft. ft. CFA - CONTINUOUS FLIGHT AUGERS CA - CONTINUOUS FLIGHT AUGER U - UNDISTURBED AFTER ft. ft. DC - DRIVING CASING RC - ROCK CORE L - LOST HRS. MD - MUD DRILLING STANDARD PENETRATION TEST-DRIVING 2" O.D. SAMPLER 1' WITH 140# HAMMER FALLING 30": COUNT MADE AT 6" INTERVALS. HILLIS - CARNES ENGINEERING ASSOCIATES, INC. RECORD OF SOIL EXPLORATION DCPL Capitol View Branch Project Name Washington DC, SE Location MSL Datum Hammer Wt. 111.25 Surf. Elev. ft 1/6/15 Date Started Elevation/ Depth Hammer Drop Pipe Size SOIL SYMBOLS/ SAMPLE CONDITIONS 140 30 2.0 B-2 Boring No. 14465A Job # SAMPLER lbs. Hole Diameter 6" in. Rock Core Diameter in. Boring Method Boring and Sampling Notes Description N/A HSA Rec. NM% Foreman M. Stawas Inspector W. Harris 1/6/15 Date Completed SPT Blows N SPT Blows/Foot Curve 10 0 I 110 I 5 I 105 I 10 100 Orange-Brown/Dark Brown/Gray, moist, loose clayey SAND with gravel and organics (SC) Possible Fill Mottled Light Gray/Red-OrangeBrown/Dark Brown/Yellow-Brown, moist, medium stiff sandy CLAY (CL) Possible Fill Dark Brown/Brown, moist, stiff, sandy SILT with clay (ML) Possible Fill 1" of Topsoil Mottled Brown/Orange-Brown, moist, very loose to medium dense silty fine SAND with clay (SM) Possible Fill I 14" 2-3-5 8 13" 3-4-6 10 15" 3-5-7 12 17" 2-2-2 4 11" 4-6-7 13 30 50 15 95 I Red-Brown with Light Gray, moist, very stiff sandy CLAY (CL) 18" 7-8-11 19 I Light Red-Brown, moist, dense silty SAND (SM) 18" 5-16-22 38 18" 15-17-16 33 18" 7-17-30 47 20 90 25 85 I 30 80 Groundwater Light Red-Brown, moist, dense to SAMPLER TYPE DRIVEN SPLIT SPOON UNLESS OTHERWISE SAMPLE CONDITIONS D - DISINTEGRATED AT COMPLETION GROUND WATER ft. Dry CAVE IN DEPTH 30.5 ft. BORING METHOD HSA - HOLLOW STEM AUGERS PT - PRESSED SHELBY TUBE I - INTACT AFTER 24 HRS. ft. ft. CFA - CONTINUOUS FLIGHT AUGERS CA - CONTINUOUS FLIGHT AUGER U - UNDISTURBED AFTER ft. ft. DC - DRIVING CASING RC - ROCK CORE L - LOST HRS. MD - MUD DRILLING STANDARD PENETRATION TEST-DRIVING 2" O.D. SAMPLER 1' WITH 140# HAMMER FALLING 30": COUNT MADE AT 6" INTERVALS. HILLIS - CARNES ENGINEERING ASSOCIATES, INC. RECORD OF SOIL EXPLORATION DCPL Capitol View Branch Project Name Washington DC, SE Location MSL Datum 111.25 Surf. Elev. ft 1/6/15 Date Started Elevation/ Depth 140 Hammer Wt. 30 Hammer Drop Pipe Size SOIL SYMBOLS/ SAMPLE CONDITIONS 2.0 B-2 Boring No. 14465A Job # SAMPLER lbs. Hole Diameter 6" in. Rock Core Diameter in. Boring Method Description Boring and Sampling Notes very dense silty SAND with Light Red-Brown clay seams (SM) encountered at 35 ft while drilling N/A HSA Rec. NM% Foreman M. Stawas Inspector W. Harris 1/6/15 Date Completed SPT Blows N SPT Blows/Foot Curve 10 I 35 30 50 75 I Light Red-Brown to Gray, moist, very dense silty SAND (SM) 18" 11-20-36 56 18" 25-41-49 90 40 70 I 45 Bottom of boring at 45 ft 65 90 Boring backfilled with grout and patched at completion 50 60 55 55 60 50 65 45 SAMPLER TYPE DRIVEN SPLIT SPOON UNLESS OTHERWISE SAMPLE CONDITIONS D - DISINTEGRATED AT COMPLETION GROUND WATER ft. Dry CAVE IN DEPTH 30.5 ft. BORING METHOD HSA - HOLLOW STEM AUGERS PT - PRESSED SHELBY TUBE I - INTACT AFTER 24 HRS. ft. ft. CFA - CONTINUOUS FLIGHT AUGERS CA - CONTINUOUS FLIGHT AUGER U - UNDISTURBED AFTER ft. ft. DC - DRIVING CASING RC - ROCK CORE L - LOST HRS. MD - MUD DRILLING STANDARD PENETRATION TEST-DRIVING 2" O.D. SAMPLER 1' WITH 140# HAMMER FALLING 30": COUNT MADE AT 6" INTERVALS. HILLIS - CARNES ENGINEERING ASSOCIATES, INC. RECORD OF SOIL EXPLORATION DCPL Capitol View Branch Project Name Washington DC, SE Location MSL Datum Hammer Wt. 111.5 Surf. Elev. ft 1/5/15 Date Started Elevation/ Depth Hammer Drop Pipe Size SOIL SYMBOLS/ SAMPLE CONDITIONS 140 30 2.0 Description B-3 Boring No. 14465A Job # SAMPLER lbs. Hole Diameter 6" in. Rock Core Diameter in. Boring Method Boring and Sampling Notes N/A HSA Rec. NM% Foreman M. Stawas Inspector W. Harris 1/5/15 Date Completed SPT Blows N SPT Blows/Foot Curve 10 I 110 I 5 I 10" 2-1-1 2 8" 2-2-2 4 10" 3-2-3 5 13" 3-2-2 4 Brown/Orange-Brown, very moist, very loose clayey GRAVEL and SAND (GC-SC) Possible Fill 3" 1-1-1 2 Red-Brown/Brown, moist, very stiff CLAY with silt and trace to some sand (CL-CH) 17" 4-7-9 16 18" 4-6-11 17 18" 13-17-22 39 18" 9-15-16 31 Orange-Brown, moist, very loose clayey SAND with gravel (SC) Possible Fill Orange-Brown to Orange-Brown/ Yellow-Brown /Light Gray, moist, soft sandy CLAY (CL) Possible Fill 4" of Asphalt 2" of Stone Orange-Brown, moist, very loose clayey SAND (SC) Possible Fill Groundwater encountered at 13.5 ft while drilling 30 50 105 I 10 100 I 15 95 I 20 90 I 25 85 I 30 Light Red-Brown to Gray, moist, dense to very dense silty SAND (SM) 80 I SAMPLER TYPE DRIVEN SPLIT SPOON UNLESS OTHERWISE SAMPLE CONDITIONS D - DISINTEGRATED AT COMPLETION GROUND WATER ft. Dry CAVE IN DEPTH 31.5 ft. BORING METHOD HSA - HOLLOW STEM AUGERS PT - PRESSED SHELBY TUBE I - INTACT AFTER 24 HRS. ft. ft. CFA - CONTINUOUS FLIGHT AUGERS CA - CONTINUOUS FLIGHT AUGER U - UNDISTURBED AFTER ft. ft. DC - DRIVING CASING RC - ROCK CORE L - LOST HRS. MD - MUD DRILLING STANDARD PENETRATION TEST-DRIVING 2" O.D. SAMPLER 1' WITH 140# HAMMER FALLING 30": COUNT MADE AT 6" INTERVALS. HILLIS - CARNES ENGINEERING ASSOCIATES, INC. RECORD OF SOIL EXPLORATION DCPL Capitol View Branch Project Name Washington DC, SE Location MSL Datum 111.5 Surf. Elev. ft 1/5/15 Date Started Elevation/ Depth 140 Hammer Wt. 30 Hammer Drop Pipe Size SOIL SYMBOLS/ SAMPLE CONDITIONS 2.0 Description B-3 Boring No. 14465A Job # SAMPLER lbs. Hole Diameter 6" in. Rock Core Diameter in. Boring Method Boring and Sampling Notes N/A HSA Rec. NM% Foreman M. Stawas Inspector W. Harris 1/5/15 Date Completed SPT Blows N SPT Blows/Foot Curve 10 30 50 35 75 I 18" 17-30-38 68 68 18" 22-30-37 67 67 40 70 I 45 Bottom of boring at 45 ft 65 Boring backfilled with grout and patched at completion. 50 60 55 55 60 50 65 45 SAMPLER TYPE DRIVEN SPLIT SPOON UNLESS OTHERWISE SAMPLE CONDITIONS D - DISINTEGRATED AT COMPLETION GROUND WATER ft. Dry CAVE IN DEPTH 31.5 ft. BORING METHOD HSA - HOLLOW STEM AUGERS PT - PRESSED SHELBY TUBE I - INTACT AFTER 24 HRS. ft. ft. CFA - CONTINUOUS FLIGHT AUGERS CA - CONTINUOUS FLIGHT AUGER U - UNDISTURBED AFTER ft. ft. DC - DRIVING CASING RC - ROCK CORE L - LOST HRS. MD - MUD DRILLING STANDARD PENETRATION TEST-DRIVING 2" O.D. SAMPLER 1' WITH 140# HAMMER FALLING 30": COUNT MADE AT 6" INTERVALS. HILLIS - CARNES ENGINEERING ASSOCIATES, INC. RECORD OF SOIL EXPLORATION DCPL Capitol View Branch Project Name Washington DC, SE Location MSL Datum Hammer Wt. 111.75 Surf. Elev. ft 1/5/15 Date Started Elevation/ Depth Hammer Drop Pipe Size SOIL SYMBOLS/ SAMPLE CONDITIONS 140 30 2.0 B-4 Boring No. 14465A Job # SAMPLER lbs. Hole Diameter 6" in. Rock Core Diameter in. Boring Method Boring and Sampling Notes Description N/A HSA Rec. NM% Foreman M. Stawas Inspector W. Harris 1/5/15 Date Completed SPT Blows N SPT Blows/Foot Curve 10 I 110 I 5 I 105 16" 2-4-7 11 17" 6-5-4 9 18" 2-1-2 3 17" WOH/12"-1 1 Gray/Yellow-Brown, moist, medium stiff CLAY with sand (CL) Possible Fill 15" 3-4-5 9 Red-Brown/Light Gray to Red Brown, moist, very stiff to hard sandy CLAY (CL) 18" 4-8-15 23 18" 6-14-20 34 18" 5-7-10 17 18" 7-11-26 37 Orange-Brown/Red-Brown/Gray, moist, stiff sandy CLAY with gravel (CL) Possible Fill Gray with Yellow-Brown, moist, medium stiff CLAY (CL) Possible Fill Red-Brown with Gray to Gray, moist to wet, very loose silty SAND (SM) Possilbe Fill I 10 4" of Asphalt No Stone Encountered Groundwater encountered at 8.5 ft while drilling 30 50 100 I 15 95 I 20 90 I 25 85 I 30 80 I SAMPLER TYPE DRIVEN SPLIT SPOON UNLESS OTHERWISE SAMPLE CONDITIONS D - DISINTEGRATED AT COMPLETION GROUND WATER ft. Dry CAVE IN DEPTH 30.5 ft. BORING METHOD HSA - HOLLOW STEM AUGERS PT - PRESSED SHELBY TUBE I - INTACT AFTER 24 HRS. ft. ft. CFA - CONTINUOUS FLIGHT AUGERS CA - CONTINUOUS FLIGHT AUGER U - UNDISTURBED AFTER ft. ft. DC - DRIVING CASING RC - ROCK CORE L - LOST HRS. MD - MUD DRILLING STANDARD PENETRATION TEST-DRIVING 2" O.D. SAMPLER 1' WITH 140# HAMMER FALLING 30": COUNT MADE AT 6" INTERVALS. HILLIS - CARNES ENGINEERING ASSOCIATES, INC. RECORD OF SOIL EXPLORATION DCPL Capitol View Branch Project Name Washington DC, SE Location MSL Datum 111.75 Surf. Elev. ft 1/5/15 Date Started Elevation/ Depth 140 Hammer Wt. 30 Hammer Drop Pipe Size SOIL SYMBOLS/ SAMPLE CONDITIONS 2.0 Description B-4 Boring No. 14465A Job # SAMPLER lbs. Hole Diameter 6" in. Rock Core Diameter in. Boring Method Boring and Sampling Notes N/A HSA Rec. NM% Foreman M. Stawas Inspector W. Harris 1/5/15 Date Completed SPT Blows N SPT Blows/Foot Curve 10 30 50 35 75 I 40 Light Red-Brown/Gray to Gray, moist, dense to very dense silty SAND (SM) 17" 16-41-50/5" 91+ 91+ 18" 22-37-49 86 86 70 I 45 Bottom of boring at 45 ft 65 Boring backfilled with grout and patched at completion 50 60 55 55 60 50 65 45 SAMPLER TYPE DRIVEN SPLIT SPOON UNLESS OTHERWISE SAMPLE CONDITIONS D - DISINTEGRATED AT COMPLETION GROUND WATER ft. Dry CAVE IN DEPTH 30.5 ft. BORING METHOD HSA - HOLLOW STEM AUGERS PT - PRESSED SHELBY TUBE I - INTACT AFTER 24 HRS. ft. ft. CFA - CONTINUOUS FLIGHT AUGERS CA - CONTINUOUS FLIGHT AUGER U - UNDISTURBED AFTER ft. ft. DC - DRIVING CASING RC - ROCK CORE L - LOST HRS. MD - MUD DRILLING STANDARD PENETRATION TEST-DRIVING 2" O.D. SAMPLER 1' WITH 140# HAMMER FALLING 30": COUNT MADE AT 6" INTERVALS. HILLIS - CARNES ENGINEERING ASSOCIATES, INC. RECORD OF SOIL EXPLORATION DCPL Capitol View Branch Project Name Washington DC, SE Location MSL Datum Hammer Wt. 111.0 Surf. Elev. ft 12/31/14 Date Started Elevation/ Depth Hammer Drop Pipe Size SOIL SYMBOLS/ SAMPLE CONDITIONS 140 30 2.0 B-5 Boring No. 14465A Job # SAMPLER lbs. Hole Diameter 6" in. Rock Core Diameter in. Boring Method Boring and Sampling Notes Description N/A HSA Rec. NM% Foreman M. Stawas Inspector W. Harris 12/31/14 Date Completed SPT Blows N SPT Blows/Foot Curve 10 110 I I 5 I 105 14" 3-3-2 5 8" 2-2-1 3 16" 1/12"-1 1 11" 3-4-5 9 Red-Brown/Brown, very moist, very dense silty SAND with gravel (SM) Possible Fill 18" 22-45-24 69 Light Brown/Orange-Brown to Mottled Light Gray/Dark RedBrown/Orange-Brown, moist, very stiff to hard CLAY with silt and trace sand (CL) 14" 7-8-13 21 18" 13-17-18 35 18" 9-13-17 30 18" 18-22-28 50 Mottled Dark Brown/Red-Brown Dark Gray, moist, very loose silty SAND with no to trace clay(SM) Possible Fill 3" of Asphalt 2" of Stone Dark Brown/Red-Brown/Dark Gray, moist, soft to very soft CLAY with sand (CL) Possible Fill Groundwater encountered at 5.5 ft I 30 50 10 100 I 15 69 95 I 20 90 I 25 85 I 30 80 I Light Red-Brown to Gray, moist, SAMPLER TYPE DRIVEN SPLIT SPOON UNLESS OTHERWISE SAMPLE CONDITIONS D - DISINTEGRATED AT COMPLETION GROUND WATER 25.2 ft. CAVE IN DEPTH 37.3 ft. BORING METHOD HSA - HOLLOW STEM AUGERS PT - PRESSED SHELBY TUBE I - INTACT AFTER 24 HRS. ft. ft. CFA - CONTINUOUS FLIGHT AUGERS CA - CONTINUOUS FLIGHT AUGER U - UNDISTURBED AFTER ft. ft. DC - DRIVING CASING RC - ROCK CORE L - LOST HRS. MD - MUD DRILLING STANDARD PENETRATION TEST-DRIVING 2" O.D. SAMPLER 1' WITH 140# HAMMER FALLING 30": COUNT MADE AT 6" INTERVALS. HILLIS - CARNES ENGINEERING ASSOCIATES, INC. RECORD OF SOIL EXPLORATION DCPL Capitol View Branch Project Name Washington DC, SE Location MSL Datum Hammer Wt. 111.0 Surf. Elev. ft 12/31/14 Date Started Elevation/ Depth 140 30 Hammer Drop Pipe Size SOIL SYMBOLS/ SAMPLE CONDITIONS 2.0 Description B-5 Boring No. 14465A Job # SAMPLER lbs. Hole Diameter 6" in. Rock Core Diameter in. Boring Method Boring and Sampling Notes N/A HSA Rec. NM% Foreman M. Stawas Inspector W. Harris 12/31/14 Date Completed SPT Blows N SPT Blows/Foot Curve 10 30 50 dense to very dense silty SAND (SM) 35 75 I 11" 27-50/5" 77+ 77+ 18" 15-28-39 67 67 40 70 I 45 Bottom of Boring at 45 ft 65 Boring backfilled with grout and patched at completion 50 60 55 55 60 50 65 45 SAMPLER TYPE DRIVEN SPLIT SPOON UNLESS OTHERWISE SAMPLE CONDITIONS D - DISINTEGRATED AT COMPLETION GROUND WATER 25.2 ft. CAVE IN DEPTH 37.3 ft. BORING METHOD HSA - HOLLOW STEM AUGERS PT - PRESSED SHELBY TUBE I - INTACT AFTER 24 HRS. ft. ft. CFA - CONTINUOUS FLIGHT AUGERS CA - CONTINUOUS FLIGHT AUGER U - UNDISTURBED AFTER ft. ft. DC - DRIVING CASING RC - ROCK CORE L - LOST HRS. MD - MUD DRILLING STANDARD PENETRATION TEST-DRIVING 2" O.D. SAMPLER 1' WITH 140# HAMMER FALLING 30": COUNT MADE AT 6" INTERVALS. HILLIS-CARNES ENGINEERING ASSOCIATES, Inc. 10975 Guilford Road, Suite A Annapolis Junction, Maryland 20701 Phone: (410)880-4788 Fax: (410)880-4098 Description of Soils – per ASTM D2487 Major Component Component Type Coarse-Grained Soils, More than 50% is retained on the No. 200 sieve Fine Grained Soils, More than 50% passes the No. 200 sieve Highly Organic Soils Component Description Symbol Gravels – More than 50% of the coarse fraction is retained on the No. 4 sieve. Coarse = 1” to 3” Medium = ½” to 1” Fine = ¼” to ½” Sands – More than 50% of the coarse fraction passes the No. 4 sieve. Coarse = No.10 to No.4 Medium = No. 10 to No. 40 Fine = No. 40 to No. 200 Silts and Clays Liquid Limit is less than 50 Low to medium plasticity Clean Gravels <5% Passing No. 200 sieve Gravels with fines, >12% Passing the No. 200 sieve GW GP GM GC Well Graded Gravel Poorly Graded Gravel Silty Gravel Clayey Gravel Clean Sands <5% Passing No. 200 sieve Sands with fines, >12% Passing the No. 200 sieve SW SP SM SC Well Graded Sand Poorly Graded Sand Silty Sand Clayey Sand Inorganic ML CL OL Silts and Clays Liquid Limit of 50 or greater Medium to high plasticity Inorganic Silt Lean Clay Organic silt Organic Clay Elastic Silt Fat Clay Organic Silt Organic Clay Peat Organic Organic Primarily Organic matter, dark color, organic odor Proportions of Soil Components Component Form Noun Adjective Some Trace With MH CH OH Description Sand, Gravel, Silt, Clay, etc. Sandy, silty, clayey, etc. Some sand, some silt, etc. Trace sand, trace mica, etc. With sand, with mica, etc. PT Particle Size Identification Approximate percent by weight 50% or more 35% to 49% 12% to 34% 1% to 11% Presence only Particle Size Boulder Cobble Gravel Sand Silt/Clay (fines) Cohesive Soils Field Description Easily Molded in Hands Easily penetrated several inches by thumb Penetrated by thumb with moderate effort Penetrated by thumb with great effort Indented by thumb only with great effort Group Name Particle dimension 12” diameter or more 3” to 12” diameter ¼” to 3” diameter 0.005” to ¼” diameter Cannot see particle Granular Soils No. of SPT Blows/ft 0–3 4–5 6 – 10 11 – 30 Greater than 30 Consistency Very Soft Soft Medium Stiff Hard No. of SPT Blows/ft Relative Density 0–4 5 – 10 11 – 30 31 – 50 Greater than 50 Very Loose Loose Medium Dense Dense Very Dense Other Definitions: Fill: Encountered soils that were placed by man. Fill soils may be controlled (engineered structural fill) or uncontrolled fills that may contain rubble and/or debris. Saprolite: Soil material derived from the in-place chemical and physical weathering of the parent rock material. May contain relic structure. Also called residual soils. Occurs in Piedmont soils, found west of the fall line. Disintegrated Rock: Residual soil material with rock-like properties, very dense, N = 60 to 51/0”. Karst: Descriptive term which denotes the potential for solutioning of the limestone rock and the development of sinkholes. Alluvium: Recently deposited soils placed by water action, typically stream or river floodplain soils. Groundwater Level: Depth within borehole where water is encountered either during drilling, or after a set period of time to allow groundwater conditions to reach equilibrium. Caved Depth: Depth at which borehole collapsed after removal of augers/casing. Indicative of loose soils and/or groundwater conditions.