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CF-TownC CHC-SY 841127GEOTECHNICAL INVESTIGATION FOR PROPOSED COPPELL CITY HALL PARKWAY BOULEVARD COPPELL, TEXAS PREPARED FOR CITY OF COPPELL COPPELL, TEXAS Maxim Engineers Inc. <~eotecsn~,ca/r¥1a[erial<' 3(}:s~ir~c/Cor~L ~ ~ia' GEOTECHNI CAL INVESTIGATION FOR PROPOSED COPPELL CITY HALL PARKWAY BOULEVARD COPPELL, TEXAS REPORT NO. C-4-0476 REPORT to CITY OF COPPELL COPPELL, TEXAS by MAXIM ENGINEERS, INC. GEOTECHNICAL/MATERIALS TESTING/CONSULTANTS DALLAS, TEXAS November 27. 1984 Maxim Engineers Inc. Maxim Engineers, Inc. Geotechnical Materials Testing Consultants November 27, 1984 Mr. Ron Ragland City of Coppell Box 478 Coppell, Texas 75019 Re: Report No. C-4-0476 Geotechnical Investigation Proposed Coppell City Hall Parkway Boulevard Coppell, Texas Dear Mr. Ragland: Submitted herein is a report summarizing the results of the geotechnical investigation performed at the above referenced project. We trust the recommendations derived from this investigation will pro- vide an adequate and economical foundation design. As your project develops we would be pleased to assist you with material quality inspec- tion and quality assurance testing. We thank you for the opportunity to provide you with our professional services. If we can be of further assistance, please do not hesitate to contact us. Very truly yours, MAXIM ENGINEERS, INC. Vice President due, P.E. President SMH: GWP :lsl cc: O'Brien, O'Brien, Nyfeler & Callaway Corporation TechniStructures 2342 Fabens F~O. Box 59902 Dallas, Texas 75229 (214) 247-7575 SYNOPSIS PROPOSED COPPELL CITY HALL PARKWAY BOULEVARD COPPELL, TEXAS REPORT NO. C-4-0476 The synopsis is included for the convenience of our clients and is intended only as a general overview of the results of this investiga- tion. Designs based upon the information in this report should be made only after reading and thoroughly understanding the recommendations as they are stated in the main body of the report. PROJECT DESCRIPTION The proposed building will be located along the south side of Parkway Boulevard, east of Denton Tap Road in Coppell, Texas. II. SUBSURFACE CONDITIONS Subsurface stratigraphy consisted of intermittent layers of dark brown, brown, and yellowish brown clays, sandy clays, clayey sands and sands underlain by a gray shale stratum encountered at a depth of 15 to 18.5 feet below the ground surface. Subsurface seepage water was encountered 10 to 20 feet below the ground surface. III. FOUNDATION TYPE The building's structural loads may be supported by auger excavated, straight-sided, cast-in-place reinforced concrete piers founded at least three (3) feet into the primary shale formation encountered 15 to 18.5 feet below the existing ground surface. These piers may be designed and proportioned using an allowable end bearing pressure of 22,000 pounds per square foot and a skin friction value of 2,750 pounds per square foot of shaft area in direct contact with the gray shale below the recommended minimum penetration. IV. FLOOR SLABS The building's floor slab may be placed on one of the following subgrade systems: a. 12 to 18 inches of select fill placed on existing compacted soils - Estimated floor slab movement 0.75 to 1.00 inch; or Maxim Engineers Inc. b. A structural floor slab system with a six (6) inch void provided between the concrete slab and the exposed subgrade. V. PAVEMENT RECOMMENDATIONS Light duty pavement may consist of four (4) inches of Portland Cement Concrete over six (6) inches of compacted subgrade. Channelized heavy traffic areas will require six (6) inches of Portland Cement Concrete* over the compacted subgrade. Weakened planes (sawed joints) of at least one fourth the pavement thick- ness should be provided at maximum spacings of 15 feet. *See Guidelines in Appendix of this report. Maxim Engineers Inc. TABLE OF CONTENTS Introduction ............................................. 1 Project Description ..................................... 2 Subsurface Conditions ................................... 2 Analyses and Recommendations ........................... 3-6 APPENDIX Field and Laboratory Investigations ..................... General Construction Recommendations ................... Guidelines for Concrete Pavement ........................ Joint Cross-Section ..................................... Plan of Borings Log of Borings Symbols and Terms used on Boring Logs Unified Soil Classification System A-1 A-3 A-7 A-10 Maxim Engineers Inc. GEOTECHNICAL INVESTIGATION FOR PROPOSED COPPELL CITY HALL PARKWAY BOULEVARD COPPELL, TEXAS REPORT NO. C-4-0476 INTRODUCTION This report transmits the findings of the geotechnical investi- gation performed at the referenced site. The purpose of this investigation was to define and evaluate the general subsurface conditions in the immediate vicinity of the proposed City Hall building. Specifically, the study was planned to determine the following: e Subsurface stratigraphy within the limits of explor- atory borings. Classification. strength and compressibility char- acteristics of the foundation strata. Suitable foundation systems and allowable soil load- ing pressures. The Potential Vertical Rise (PVR) of critical soil strata. Interior floor slab recommendations to accommodate anticipated subgrade movements. Construction requirements for the alteration of existing site conditions. Construction requirements for the placement of necessary earth embankments or fills. Generalized section recommendations for roadways and parking area pavements. Other soil related problems which may be revealed by the investigation. Maxim Engineers Inc. This study was performed in accordance with the request of Mr. Tony Callaway with O'Brien, O'Brien, Nyfeler ~ Callaway Corporation in Dallas, Texas. To accomplish the intended purposes, a three phase study program was conducted which includ- ed: a) a field investigation consisting of nine (9) exploration test borings with samples obtained at selected intervals; b) a laboratory testing program designed to evaluate the expansive and strength characteristics of the subsurface soils; and c) an engineering analysis of the field and test data for foundation and pavement design recommendations. No additional analysis was requested or performed. A brief description of the various field and laboratory tests and their respective results is included in the Appendix of this report. II. PROJECT DESCRIPTION The proposed project will consist of a two-story City Hall. The building will be built at the location indicated on the plan of borings included in the appendix of this report. Light to moderate structural loads are anticipated. The project site is located along the south side of Parkway-Boule- vard, east of Denton Tap Road in Coppell, Texas. III. SUBSURFACE CONDITIONS The subsurface soils encountered at the test borings locations consisted of a dark brown, brown, and yellowish brown clays, sandy clays, clayey sands and sands that extended to a depth of 15 to 18.5 feet below the ground surface, where a gray shale stratum was encountered. Maxim Engineers Inc. At the time this investigation was performed, groundwater was encountered at the borehole locations at depth ranging between 10 and 20 feet. The depth to groundwater may change with variations in atmospheric conditions, therefore, its depth should be verified just prior to construction that may be affected by its presence. If there is a drastic change, then Maxim Engineers, Inc. should be notified to review the effect it may have on the recommended foundation systems. IV. ANALYSES AND RECOMMENDATIONS The professional services which have been performed, the findings obtained and the recommendations prepared were accomplished in accordance with currently accepted geotechnical engineering prin- ciples and practices. The possibility always exists that the sub- surface conditions at the site may vary somewhat from those encountered in the boreholes. The number of borings and spacing was chosen in such a manner as to decrease the possibility of undiscovered abnormalities, while considering the nature of load- ing, size, and cost of the project. If there are any unusual conditions differing from those described herein, Maxim Engineers, Inc. should be notified to review the effects on the performance of the designed foundation. The recommendations given in this report are applicable only for the design of the previously described City Hall to be constructed at locations indicated at this site; they should not be used for any other purpose. This firm is not responsible for the conclusions, opinions, or recom- mendations made by others based on this information. Maxim Engineers Inc. 1. Support of Structural Loads The building's structural loads may be supported by a founda- tion system consisting of auger excavated, straight-sided, cast-in -place, reinforced concrete piers founded at least three (3) feet into the primary shale formation encountered 15 to 18.5 feet below the existing ground surface. The piers may be designed using an allowable end bearing pressure of 22,000 pounds per square foot and a skin friction value of 2,750 pounds per square foot of shaft area in direct contact with the gray shale below the recommended minimum penetration. Foundations designed and constructed in accordance with the recommendations provided in this report will have a factor of safety of 2.5 or more against shear type failure. Total settlement potential is less than one (1) inch with differen- tial settlement potential on the order of 0.50 to 0.75 inch. The majority of all settlement should occur during initial loading. The subsurface water conditions encountered at the test boring locations indicate that temporary casing of some of the foundation piers will be required. 2. Soil Movement The near surface soils encountered at the site exhibited relatively moderate plasticity indices. Some of these soils should be considered as relatively active and capable of vertical soil movements ranging between 1.00 and 2.00 inches with changes in moisture conditions. Maxim Engineers Inc. 5 Floor Slabs To reduce the effect of the moisture induced soil movement on the building, the floor slab may be placed on 12 to 18 inches of select fill that is placed above the surrounding grade. The select fill should be processed in accordance with the recommendations provided in the Appendix of this report. Estimated vertical differential slab movements 0.75 to 1.00 inch. Considerable more movement will occur in areas where water is allowed to pond next to the building during or after construction. In areas where floor slab movement can not be tolerated, a structural floor slab with a six (6) inch void provided under the concrete slab may be used. All grade beams should be underlain by a six (6) inch void space provided between the concrete and the surface soils· Pavement Recommendations Prior to beginning pavement construction, soils at the natural ground surface in the proposed parking area should be scari- fied and grubbed to a depth of at least six (6) inches. Orga- nic materials and any vegetation should be removed from the site. The scarified areas along with areas requiring addi- tional fill should then be recompacted to a minimum of 95 percent of the maximum dry density as defined by ASTM D 698 (Standard Proctor Test) at a moisture content within three (3) percent of the optimum moisture value. Maxim Engineers Inc. The following pavement sections are presented for your consid- eration: Areas of Light Traffic (Auto Parking) 4.00 inches Portland Cement Concrete* (15 foot joint spacing) 6.00 inches Compacted Subgrade Areas of Channelized Traffic 6.00 inches Portland Cement Concrete* (15 foot joint spacing) 6.00 inches Compacted Subgrade *See Guidelines for Concrete Pavement in the Appendix of this report. The light duty pavement is designed for 200 to 300 vehicles per day, two (2) to three (3) of which may be heavy commercial trucks. The channelized heavy traffic pavement is designed to sustain 300 to 500 vehicles per day including five (5) to seven (7) heavy commercial vehicles. Maxim Engineers Inc. FIELD AND LABORATORY INVESTIGATIONS PROPOSED COPPELL CITY HALL PARKWAY BOULEVARD COPPELL, TEXAS REPORT NO. C-4-0476 A-1 Field Investigation Soil conditions at the project site were determined by nine (9) intermittent sample borings which were drilled during November, 1984. The locations of these borings are shown on the sheet entitled "Plan of Borings" of this report. Descriptions of the various strata encountered in each of the borings and the depths at which samples were obtained are presented on the individual "Log of Borings". Undisturbed specimens of cohesive soils were obtained with thin- wailed Shelby tube samplers (ASTM D 1587). The soil specimens were extruded from the tube in the field, logged, sealed and pack- aged to maintain "in situ" conditions. Disturbed samples of the noncohesive granular or stiff to hard cohesive materials have been obtained utilizing a two (2) inch O.D. split-spoon sampler in conjunction with the Standard Penetra- tion Test (ASTM D 1586). This test employs a 140 pound hammer Maxim Engineers Inc. A-2 that drops a free fall vertical distance of 30 inches, driving the split-spoon sampler into the material. The number of blows required for 18 inches of penetration is recorded and the value for the last 12 inches, or the penetration obtained from 100 blows, is reported as the Standard Penetration Value (N) at the appropriate depth on the attached "Log of Borings". II. Laboratory Soils Tests Laboratory soil tests were performed on samples recovered from the borings to verify visual classification and determine the perti- nent engineering properties of the soils encountered. Atterberg Limits, Moisture Content, Unit Dry Weight and Percent Passing A No. 200 U.S. Sieve tests were performed on representa- tive samples in order to classify them according to the Unified Soil Classification System. The results of all the laboratory and field tests are tabulated on the "Log of Borings" presented in the Appendix. Unconfined Compressive Strength tests were performed on selected undisturbed soil samples to determine the ultimate unconfined compressive strength of the different subsurface strata encounter- ed. The results of all the laboratory and field tests are tabulated on the "Log of Borings" presented in the Appendix. Maxim Engineers Inc. GENERAL CONSTRUCTION RECOMMENDATIONS PROPOSED COPPELL CITY HALL PARKWAY BOULEVARD COPPELL, TEXAS REPORT NO. C-4-0476 A-3 Site Preparation Prior to placing any fill material, all existing surface vegeta- tion should be removed. All exposed surfaces should then be scar- ified, watered as required and recompacted to a minimum of 95 per- cent of the maximum dry density as defined by ASTM D 698 (Standard Proctor Test) at a moisture content within three (3) percent of the optimum moisture value. The site may then be filled to grade using a suitable fill material, free from deleterious matter. Fill materials should be placed in six (6) to eight (8) inch loose lifts at moisture contents within three (3) percent of optimum and each lift compacted to between 93 and 100 percent of the maximum dry density as defined in ASTM D 698. inspected and approved by a qualified supervised by a Geotechnical Engineer before added. Each lift should be engineering technician, another lift is II. Select Fill "Select Fill" as referred to in the main body of the report should consist of clayey sands free of organic materials and having a Maxim Engineers Inc. A-4 Plasticity Index between four (4) and fifteen (15), and a Liquid Limit of 40 or less. Placement and compaction of the select fill should be performed in accordance with the above mentioned "Site Preparation" section. III. Foundation System Normal construction procedures for this area of Texas should be employed in the installation of drilled, cast-in-place, straight shaft foundations. Concrete and reinforcing steel should be placed immediately after the excavation has been completed and inspected by a Soils Engineer to assure compliance with design assumptions and to verify: A) the bearing stratum; B) the minimum penetration; C) the removal of all smear zones and cuttings; and D) that groundwater seepage is correctly handled. In no event should an excavation be allowed to remain open for more than eight (8) hours. Ail concrete placed in excavations in excess of ten (10) feet in depth should be properly tremied to prevent separa- tion of the aggregates. Based on borehole information, it appears that temporary casing will be required at some locations to avoid sloughing of the upper soils and seepage infiltration in the area of the proposed excavations. IV. Surface Drainage, Vegetation Drainage should be maintained away from the foundations, both dur- ing and after construction. Trees and large shrubs can, by trans- piration, remove water from the clays and cause shrinkage of these Maxim Engineers Inc.. A-5 soils and settlement of the floor slabs. Therefore, any shrubs or trees planted for landscaping should be located at least one and one-half their anticipated mature height away from the building. Ve Secondary Design Considerations The following information has been assimilated after examination of numerous problems dealing with similar soil throughout the area. It is presented here for your convenience. If these fea- tures are incorporated in the overall design of the project, the performance of the structure will be improved. A. Roof drainage should be collected by a system of gutters and downspouts and transmitted by a pipe to a storm drainage system or to a paved surface where the water can drain away without entering the soil, B. The sidewalks should not be structurally connected to the building. They should be sloped away from the building so that water will be drained away from the structure. Ce Special consideration should be given to completion items out- side the building area such as stairs, walkways, signs, etc. They should be adequately designed to sustain the potential vertical movements mentioned in the main body of the report. Maxim Engineers Inc. _ A-6 D. Parking lots, streets and surface drainage should be sloped away from the buildings on all sides. Water should not be allowed to pond near the buildings after the slab has been placed. Et Backfill for utility lines should be carefully placed so that they will be stable. If the backfill is too dense or too dry, swelling may form a mound along the ditch line. If the back- fill is too loose or too wet, settlement may form a sink along the ditch line. Either case is undesirable since several inches of movement is possible and floor cracks are likely to result. The soils should be processed using the previously discussed compaction criteria. Where the utility lines pass through the parking lot, the top 6 inches should be compacted similarly to the remainder of the lot. The floor slab placed at or below existing grades should be provided with a moisture barrier in order to prevent wet spots. Maxim Engineers Inc.. GUIDELINES FOR CONCRETE PAVEMENT PROPOSED COPPELL CITY HALL PARKWAY BOULEVARD COPPELL, TEXAS REPORT NO. C-4-0476 A-7 CHARACTERISTICS OF CONCRETE: 1. Ail concrete should have a specified 28 -day compressive strength of 3,000 psi. Concrete should be manufactured and delivered in accordance with ASTM C 94; Standard Specification for ready mixed concrete. 2. Four (4) to six (6) percent air should be entrained in the concrete. 3. The maximum coarse aggregate size should not be greater than one-fourth the slab depth. 4. Maximum slump should be four (4) inches + one (1) inch. II. SUBGRADE PREPARATION: 1. Prior to beginning paving operations, all vegetation should be removed to a depth of at least six (6) inches. The exposed surface should then be scarified and recompacted to a minimum of 95 percent of the maximum dry density as determined by ASTM D 698 [ Standard Proctor Test) at a moisture content within three (3) percent of the optimum moisture value. Maxim Engineers Inc. A-8 e In the event that additional fill is necessary to bring the parking area to grade, it should be placed in 6 to 8 inch loose lifts and compacted to a minimum of 95 percent of the maximum dry density as determined by ASTM D 698 (Standard Proctor Test) at a moisture content within three (3) percent of the optimum moisture value. 4. The subgrade should be in a moist condition at the time con- crete is deposited thereon. Using coarse sand (sand cushion) as a leveling material is not recommended. Surface runoff water may be piped through the coarse material and adversely affect the underlying subgrade. III. JOINT S: 1. Recommended joint spacings are provided in the "Pavement Recommendations" section of this report. Control joints or contraction joints should be formed by one of the following methods: sawed, hand-formed or formed by premolded filler. Joint depth should be equal to 1/4 of the slab thickness. Hand-formed joints should have a maximum edge radius of 1/4 inch. Sawing of joints should begin as soon as the concrete has hardened sufficiently to permit sawing with- out excessive ravelling. All joints should be completed before uncontrolled shrinkage cracking occurs. Joints should Maxim Engineers Inc. A-9 be continuous across the slab unless interrupted by full-depth premolded joint filler, and should extend completely through the curb. Joint openings wider than 1/4 inch should be cleaned and sealed before opening parking area to traffic. Expansion joints or isolation joints should be used to isolate fixed objects abutting or within the paved area. They should contain premolded joint filler for the full depth of the slab and should be sealed prior to opening to traffic. 4. Utilization of an integral curb is recommended. Maxim Engineers Inc. Structure I i I Isolation Joint X. , Expansion I 1 Material -~d{Butt-faced Construction Joint JOIb~ CROSS-SECTIONS iSawed Joint 4 Typical Premolded Filler Jo.int, , 17 .~enolded Filler Flush with Surface Keyed Construction Joint d iHand-Formed Joint -V Thickened Edge Isolahion Joint Expansion Material , - Use only where wheel loads will cross the joint Structure Transverse Oonstruction Joint Note: All joints should be cleaned and sealed prior to opening to traffic. PARKWAY BOULEVARD _..~..~ B-6 B-7 B-I t~ B-4 ~B-3 -L1 ~._~ r-F · PROPOSED COPPELL CITY HALL COPPELL, Log of Boring INumber [Location B-1 See Plan of Borings Project Proposed Coppell City Hill Parkway Boulevard Coppell, Texas Type ~ ~ ~ Intermittent Sampling ~ g . Surface Elevation o . = 'o ~ g . ~ = ~ ~ Unknown ~.~ STRATUM DESCRIPTION 10 Non,-?la ;tic BROWN SAND 2.5 ' ( D~ BRO~ S~DY CLAY 13 120 6,020 ~ (Yellowish bro~ sand and gravel seams starting at 10.0') 11 16.0' (CL) 30 72 37~ 35 94 D~K G~Y S~E 25 50 ~ 25.5' - -,, Completion Dopth Dato I Wator Obviations 25.5' 11-12-84~ Encountered at 10.0' Maxim Englneem Log of Boring INumberIL°cati°n B-2 See Plan of Borings Project Pro. posed Coppell City Hall Parkway Boulevard Coppell, Texas -- Type i Intermittent Sampling ~ ~ . S,,rface Elevation O i ~ 9 ~ g Unknown ~ .~ o STRATUM DESCRIPTION ~5 ]~3 2~580 BRO~ S~DY C~Y 2. ~' (C~) 11 122 22 15 7 4,570 5 D~K BRO~ SA~Y C~Y 13 117 3,060 (Gravel seams starting at 10.0') 15.0' (CL) D~ G~Y S~E 72 ~ 20 25 100~  'lb' 25.5' _ _ *THD Cone Penetration Test I I Completion Depth Date ~ Water Obviations 25.5' 11-12-84~ Encountered at 15.0' Maxim Englneem LogofBoringIB-3 IL°cati°n See Plan o:f Borings Project Proposed Coppell City Hall Parkway Boulevard Coppell, Texas ~. Intermittent Sampling ~ ~ Surface Elevation & ¢ -";':'~ '~ ,-- '~ m ~ I~1~ ~ STRATUM DESCRiPTiON ~ - _ ,,~  Z6 ~8 30 ]5 Z5 8~000 ~0~ S~D~ C~A~ 2.5' (c~) ~ L2~ 6~460 s~e 8~a~e~ 7.0' (C~) 13 118 1,670 15 18 15 3 26 ~o YELLOWISH BRO~ A~ G~Y C~YEY S~D w~th some gravel 11 26 1~ 12 2~ ~S .0' (SC) D~ G~Y SH~EY 17.0~ 93 9,~ DA~ G~Y SHOE 100· 6,~ 25.5~ _ Gomplotion ~pth D,to [ W~t~r 25.5~ 11-12-8~I Encountered at 20.0' Maxim Englneer~ Log of Boring INumberIL°cati°n B-4 See Plan of Borings Project Proposed Coppell City Hall Parkway Boulevard Coppell, Texas ~ Intermittent Sampling oU.E g o" Surface Elevation & ~ ~ ._ o STRATUM DESCRIPTION ~ 15 114 29 16 13 2~850 BRO~ S~DY C~Y with yellowish 2.0' bro~ and red sand seams (CL) D~ BRO~ SA~Y C~Y 14 117 3,800  ~0.0' (c~) 10 BRO~ SA~ ~ G~VEL ~4.5' (s~) 18 G~Y SH~EY CLAY 18.5' 0 9~ 10' 16 DA~ G~Y SHOE ~0~, ,,, 1" 25.5' I ~ ~ *T~ Cone Penetration Test Completion Depth Date ~ Water Obviations 25.5 ' 11-12-84~ None encountered Maxim Englneem Log of Boring INumber IL°cati°n B-5 See Plan of Borings Project Proposed Coppell City Hall Parkway Boulevard Coppell, Texas Intermittent Sampling ~ ~ e~ c ~Eg' "' .... Surface Elevation O lEI~~ ~'~--' & ~ .- ~ STRATUM DESCRIPTION ;m~  YELLOWISH BRO~ S~Y C~Y 14 28 14 14 45 2.0 ' (CL) BRO~ S~DY CLAY with some gravel ' 13 [17 4,280 5.0' (C~) 16 115 30 14 16 D~ BRO~ S~Y C~Y 10 ' 15.0 ' (CL) G~Y S~EY C~Y 30 17.0' D~ G~Y S~E ~s ~ ~o~ 25.5' __ ~ [ *THD Cone Penetration Test I I Completion ~pth Date ~ Water Obviations ~ 5' 11-12-84~ Encountered at 15.0' Maxim Englneer~ Log of Boring INumber B-6 It°catl°n See Plan of BorinRs Project Proposed Coppell City Hall Parkway Boulevard Coppell, Texas Continuous Sam~lin~ ~ STRATUM DESCRIPTION o  Z8 [t2 36 ~6 20 8~390, 2.0' (c[) 5.0' _ _ (sc) Completion Depth Date ~ Water Obviations Maxim Englneera Log of Boring 1Number IL°cafl°n B-7 See Plan of Borings Project Proposed Coppell City Hall Parkway Boulevard Coppell~ Texas ~ 3 ~ Continuous SamDlin~ ~ ~ ~ O0 ~ o  15 114 BROWN CLAYEY SAND with some gravel 8 125 16 14 2 4.0' (sc) ~~ ~.0' ,A~_ B~O~ SA~Y C,.AY _ (CL)~V 11~ ~,~00 I I I Completion Depth Date I Water Observations 5.0' 11-12-841 None encountered Maxim Engineers Log of Boring INumber Location B-8 I See Plan of Borings Project Proposed Coppell City Hall Parkway Boulevard Coppell, Texas ~ ~. ContinUous Sampling. . ~ ~g STRATUM DESCRIPTION BRO~ C~YEY S~ s- 5.0' _ 5.0 ' 11-12-8~~ None encountered Maxim Engineers Log of Boring [Number B-9 I L°cati°n See Plan of Borings project Proposed Coppell City Hall Parkway Boulevard Coppell, Texas Type Continuous Sampling  ~ sRo~ cL^~Y sm 11 122 10 is 4 3,870 ... 4.0' (sc) .5 ~ 5.0 ' BROWN SgaNDY CLAY (CL) 1 ? Completion Depth Date ! Water Observations I 11-12-84 None encountered 5.O' Maxim Englneem Symbols and Terms Used on Boring Logs Soil or Rock Types Sampler Types CLAY CLAYEY o e ' CONGLOMERATE Tube Core Spoon Auger Recoveq Consistency of Cohesive Soils DESCRIPTIVE TERM UNCONFINED COMPRESSIVE STRENGTH (TON/SQ. FOOT) Very Soft Less than 0.25 Soft 0.25-0.50 Firm 0.50-1.00 Stiff 1.00-2.00 Very Stiff 2.00-4.00 Hard More than 4.00 Relative Density of Cohesionless Soils STD. PENETRATION RESISTANCE BLOWS/FOOT DESCRIPTIVE TERM RELATIVE DENSITY 0-10 Loose 0 TO 40% 10-30 Medium Dense 40 TO 70% 30-50 Dense 70 TO 90% OVER 50 Very Dense 90 TO 100% Soil Structure CALCAREOUS SLICKENSlDED LAMINATED FISSURED INTERBEDDED Containing deposits of calcium carbonate: generally nodular Having inclined planes of weakness that are slick and glossy in appearance. Composed of thin layers of varying color and texture. Containing shrinkage cracks frequently filled with fine sand or silt. Usually more or less vertical. Composed of alternate layers of different soil types. Physical Properties of Rock VERY SOFT OR PLASTIC SOFT MODERATELY HARD HARD VERY HARD POORLY CEMENTED OR FRIABLE CEMENTED Hardness and Degree of Cementation Can be remolded in hand: corresponds in consistency up to very stiff in soils. Can be scratched with fingernail. Can be scratched easily with knife: Cannot be scratched with fingernail. Difficult to scratch with knife. Cannot be scratched with knife. Easily crumbled. Bound together by chemically precipitated material occurring in the interstices between allogenic particles of rock -- quartz, calcite, dolomite, siderite and iron oxide are common cementing materials. Physical Properties of Rock UNWEATHERED SLIGHTLY WEATHERED WEATHERED EXTREMELY WEATHERED Degree of Weathering Rock in its natural state before being exposed to atmospheric agents. Noted predominantly by color change with no disintegrated zones. Complete color change with zones of slightly decomposed rock. Complete color change with consistency, texture, and general appearance approaching soil. Maxim Engineers Inc. SOIL CLASSIFICATION SYSTEM SYM- TYPICAL NAMES MAJOR DIVISIONS BOLS GW Well graded gravels, gravel * sand mixtures, little or no fines. CLEAN GRAVELS GRAVELS (Little or no fines) GP Poorly graded gravels or gravel - sand (More than 50% of mixtures, little or no fines. coarse fraction is LARGER than the COARSE No. 4 sieve size) GRAVELS GM Silty gravels, gravel - sand - silt mixtures. GRAINED WITH FINES SO! LS (Appreciable amt. (More than 50% of of fines) GC Clayey gravels, gravel - sand - clay mixtures. material is LARGER than Well graded sands, gravelly sands, little No. 200 sieve SW or no fines. size) CLEAN SANDS (Little or no fines) Poorly graded sands or gravelly sands, SANDS SP little or no fines. (More than 50% of coarse fraction is SMALLER than the SM Silty sands, sand-silt mixtures. No. 4 sieve size) SANDS WITH FINES (Appreciable amt. of fines) SC Clayey sands, sand-clay mixtures. Inorganic silts and very fine sands, rock flour, U L silty or clayey fine sands or clayey silts with slight plasticity. Inorganic clays of iow to medium plasticity, SILTS AND CLAYS CE gravelly clays, sandy clays, silty clays, FINE (Liquid limit LESS than 50) lean clays. GRAINED SOl LS (More than 50% of OL Organic silts and organic silty clays of Iow plasticity. material is SMALLER than No. 200 sieve MH Inorganic silts, micaceous or diatomaceous fine sandy or silty soils, elastic silts. size) SILTS AND CLAYS (Liquid limit GREATER than 50) CH Inorganic clays of high plasticity, fat clays. OH Organic clays of medium to high plasticity, organic silts. HIGHLY ORGANIC SOl LS PT Peat and other highly organic soils. BOUNDARY CLASSIFICATIONS: Soils possessing characteristics of two groups are designated by combinations of group symbols. Maxim Engineers Inc.