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Denton Tap 1A-SY050311 REPORT OF SUBSURFACE EXPLORATION AND GEOTECHNICAL ENGINEERING SERVICES WACHOVIA BANK GRANDY'S ADDITION DENTON TAP ROAD COPPELL, TEXAS FOR WACHOVIA CORPORATE REAL ESTATE MARCH 11, 2005 ENGINEERING CONSULTING SERVICES~ LTD. Geotechnical · Construction Materials · Environmental Mr. Ken Clausen Wachovia Corporate Real Estate 5080 Spectrum Blvd. Suite 400 Addison, Texas 75001 Reference: Mamh 11, 2005 ECS Project No. 19:4236 Report of Subsurface Exploration and Geotechnical Engineering Services Wachovia Bank Grandy's Addition Denton Tap Road Coppell, Texas LDAC #141-9619-00 Dear Mr. Clausen: Engineering Consulting Services, Ltd. has completed the subsurface exploration for the proposed bank building at the referenced site in Coppell, Texas. The enclosed report describes the subsurface exploration procedures, laboratory testing, and geotechnical recommendations for development of the site. A Boring Location Diagram is included in the Appendix of this report along with the Boring Logs performed for the exploration. We appreciate this opportunity to be of service to you during the design phase of this project. If you have any questions with regard to the information and recommendations presented in this report, or if we can be of further assistance to you in any way during the planning or construction of this project, please do not hesitate to contact us at (972) 392-3222. Respectfully, ENGINEERING CONSULTING SERVICES, LTD. Mark A. Mendel, P.E. i~ .............................. ~Damel L. Fmnkhn, Jr., P.E. Project Engineer ~I.,E.L..~..F..~..?...LI..N:..J,.II:~ Vice President/Principal Engineer '~. 87430 The seal appearing on this document was authorized by Daniel L. Franklin, Jr., P.E. 87430 on March 11, 2005 cc: Ms. Kathryn Rabuse, AIA Litl. le Diversified Architectural Consulting (2 U.S. Mail} (1 Electronic Copy) 4950 Keller Springs Road, Suite 480, Addison, Texas 75001 · (972) 392-3222 · FAX (972) 392-0102 Al~rdeei~ MD* · Atlanta, GA · Austin~ TX · BaRimo~e, MD - Chantilly, VA Charlotte, NC Chicago, IL Dallas, TX Danville, VA REPORT PROJECT Subsurface Exploration and Geotechnical Engineering Services Wachovia Bank Grandy's Addition Denton Tap Road Coppell, Texas CLIENT Wachovia Corporate Real Estate 5080 Spectrum Blvd. Suite 400 Addison, Texas 75001 SUBMITTED BY Engineering Consulting Services, Ltd. 4950 Keller Springs Road Suite 480 Addison, Texas 75001 PROJECT #19:4236 DATE March 11,2005 ECS Project No. 19:4236 Wachovia Bank Coppell, Texas TABLE OFCONTENTS PROJECT OVERVIEW Introduction Scope of Work Proposed Construction Purposes of Exploration EXPLORATION PROCEDURES Subsurface Exploration Procedures Laboratory Testing Program EXPLORATION RESULTS Site Conditions Subsurface Conditions Groundwater Observations ANALYSIS AND RECOMMENDATIONS Earthwork Operations Building Pad Preparation Foundation Recommendations Monolithic Slab Foundation Straight-Sided Drilled Shaft Foundation Construction Considerations - Drilled Shafts Grade Beams - Drilled Shafts Pavement Subgrade Pavement Sections Drainage Closing APPENDIX PAGE 1 1 1 1 1 2 2 2 3 3 3 4 4 5 5 7 7 8 8 9 9 9 10 10 12 ECS Project No. 19:4236 Wachovia Bank Coppell, Texas PROJECT OVERVIEW Introduction This report presents the results of our subsurface exploration and geotechnical engineering recommendations for the proposed bank building located at the northwest coruer of Denton Tap Road and Fitness Court at the former Grandy's Restaurant i n Coppell, Texas. The Boring Location Diagram included in the Appendix of this report shows the approximate location of this project. Scope of Work The conclusions and recommendations contained in this report are based on four soil borings sampled in the vicinity of the proposed building and paved areas/drive lanes. Borings B-1 and B- 2 were drilled to a depth of about 20 feet below existing grade in the proposed building footprint. Borings B-3 and B-4 were drilled to a depth of about 5 feet below exisfmg grade in the proposed paved areas and overhead canopy/drive-through area. The results of the soil borings, along with a Boring Location Diagram showing the approximate locations where the borings were performed, are included in the Appendix of this report. This report also presents our recommended gcotcchnical design parameters for foundation design for the project. In addition, the report provides construction considerations based upon the results of the soil borings and our previous experience hi this area. Recommendations for site grading and area paving are also provided. Proposed Construction According to the information provided, we understand the project consists of constructing an approximate 4,000 square foot branch bank building. It is our understanding that the structure will most likely be steel framed with exterior concrete masonry trait (CMU) walls. Associated paved parking areas and drive lanes are also planned for the site. Purposes of Exploration The purposes of this exploration were to explore the soil and groundwater conditions at the site and to develop engineering recommendations to guide design and construction of the project. We accomplished these purposes by: Drilling four borings in the vicinity of the proposed building footprint and pavement areas/drive lanes to depths of about 5 and 20 feet to explore the subsurface soil and groundwater conditions. ECS Project No. 19:4236 Wachovia Bank Coppell, Texas Performing laboratory tests on selected representative soil samples from the bork~gs to evaluate pertinent engineering properties. 3. Analyzing the field and laboratory data to develop appropriate engineering recommendations. EXPLORATION PROCEDURES Subsurface Exploration Procedures The soil borings were located in the field by a representative of ECS, Ltd. using taping procedures based on landmarks shown on the site plan provided by the architect. The soil borings were performed with a track-mounted rotary-type auger drill rig that utilized continuous flight augers to advance the boreholes. Representative samples were obtained using thin-walled tube and split-barrel sampling procedures in general accordance with ASTM Specifications D-1587 and D-1586, respectively. In the thin- walled tube sampling procedure, a thin-walled seamless steel tube with a sharp cutting edge is pushed hydraulically into the ground to obtain relatively tmdisturbed samples of cohesive or moderately cohesive soils. In the split-barrel sampling procedure, a standard 2-inch O.D. split- barrel sampling spoon is driven into the ground with a 140-pound hammer falling 30 inches. The number of blows required to advance the sampling spoon the last 12 inches of a nominal 18-inch penetration is recorded as the standard penetration resistance value. These values are indicated on the boring logs at the depth of occurrence. Texas cone penetrometer tests were performed to evaluate the load carrying capacity of the shale encountered. The tests were performed in general accordance with test method Tex-132-E in the Texas Department of Transportation (TxDOT) Manual of Testing Procedures. The results of the tests are shown on the attached boring logs at the depths of occurrence. Field logs of the soils encountered in the borings were maintained by the drill crew. After recovery, each geotechnical soil sample was removed fi.om the sampler and visually classified. Representative portions of each soil sample were then wrapped in plastic and transported to our laboratory for further visual examination and laboratory testing. After completion of the drilling operations, the boreholes were backfilled with auger cuttings to the existing ground surface. Laboratory Testing Program Representative soil samples were selected and tested in our laboratory. The soil samples were tested for moisture content, dry trait weight, unconfined compressive strength, percent passing the No. 200 sieve, and Atterberg limits. A calibrated hand penetrometer was also used to estimate ECS Project No. 19:4236 Wachovia Bank Coppell, Texas the unconfined compressive strength of several of the soil samples. The calibrated hand penetrometer has been correlated with unconfined compression tests and provides a better estimate of the soil consistency than visual observation alone. These test results are provided on the attached boring logs in the Appendix. An experienced geotechnical engineer classified each soil sample on the basis of texture and plasticity in general accordance with the Unified Soil Classification System. The group symbols for each soil type are indicated in parentheses following the soil descriptions on the boring logs. A brief explanation of the Unified System is included with this report. The geotechnical engineer grouped the various soil types into the major zones noted on the boring logs. The stratification lines designating the interfaces between earth materials on the boring logs and profiles are approximate; in sim, the transitions may be gradual. The soil samples will be retained in our laboratory for a period of 60 days, after which, they will be discarded unless other instructions are received as to their disposition. EXPLORATION RESULTS Site Conditions The site of this investigation is located at the northwest comer of Denton Tap Road and Fitness Court in Coppell, Texas. The site is located within a commercial area. At the time of this investigation, the site was occupied by a former Grandy's Restaurant. Subsurface Conditions The boring locations were selected to explore the proposed building and paved areas/drive lanes. The soil conditions encountered at the boring locations can be summarized as follows. Stratum I consists of stiff to very stiff, brown gray, and red SANDY CLAY (CL) and CLAY (CH) FILL, with trace gravel. This stratum was encountered at the ground surface in all the borings, and extended to depths of about 2 to 4 feet below existing grade. The Liquid Limit of this stratum was 57 percent with a corresponding Plasticity Index (PI) of 36 percent. The Stratum I clay soils are plastic and susceptible to moisture induced volumetric changes. Stratum II consists of very stiff to hard, red-brown, gray and dark gray SANDY CLAY (CL), with trace calcareous and ferrous nodules. This stratum was encountered below Stratum I and extended to depths of 6 feet at Borings B-1 and B-2, and extended to the 5-foot termination depths at Borings B-3 and B-4. Liquid Limits (LL) ranged from 31 to 37percent with corresponding Plasticity Indices (PI) of 16 to 23 percent. The amount of particles passing the No. 200 sieve was 61 percent. The unconf'med compressive strength of these soils was measured to be 5,270 psf. The Stratum II clay soils are slightly to moderately plastic. ECS Project No. 19:4236 Wachovia Bank Coppell, Texas Stratum III consists of stiff to very stiff, light gray and tan, SANDY CLAY (CL) with trace calcareous and ferrous nodules. This material was encountered below Stratum II and extended to about the 12-foot depth at the building borings. The LL of this Stratum ranged from 32 to 41 percent with PI's ranging from 19 to 26 percent. The amount of particles passing the No. 200 sieve ranged from 53 to 66 percent. The unconfined compressive strength of this stratum was measured to be 3,380 psf. Stratum IV consists of stiff, red-tan and light gray, SANDY CLAY (CL) and medium dense CLAYEY SAND (SC) with gravel. This Stratum was encountered below Stratum III and extended to depths of about 16 to 17 feet in the building borings. The standard penetration N value of this stratum was 12 blows per foot. Stratum V consists of dark gray SHALE (CH) with trace gravel. This stratum was encountered below Stratum IV and extended to the 20 foot termination depths of Borings B-1 and B-2. The standard penetration N Value was 77 blows in 11 inches and the Texas Cone Penetrometer test yielded a value of 100 blows for 6 inches of penetration. Refer to the attached boring logs for a more detailed description of the subsurface conditions encountered in the borings. The specific soil types observed at the borings are noted on the boring logs, enclosed in the Appendix. Groundwater Observations The borings were monitored while drilling and after the completion of drilling for the presence and level of groundwater. Groundwater seepage was observed at about the 14-foot depth, within Stratum IV, while advancing the borings. Fluctuations of the groundwater level can occur due to seasonal variations in the amount of rainfall, runoff and other factors not evident at the time the borings were performed. The possibility of groundwater level fluctuations should be considered when developing the design and construction plans for the project. Groundwater conditions may require special attention if encountered during construction. ANALYSIS AND RECOMMENDATIONS The following 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, ECS, Ltd. should be consulted so that the recommendations of this report can be reviewed. ECS Project No. 19:4236 Wachovia Bank Coppell, Texas Earthwork Operations In preparing the site for construction, all loose soil, vegetation, organic soil, stumps/mots, or other unsuitable materials should be removed fi'om all proposed building and paving areas, and any areas receiving new fill. Following stripping of the site and before placing any fill, we recommend pmofrolling the site with heavy construction equipment such as a fully loaded semper or tandem axle dump track with a minimum axle load of 10 tons. The purpose of the pmofi'olling is to attempt to locate any sell or compressible soils prior to placing new fill. Unsuitable materials located during proofrolling should be removed to finn ground and replaced with properly compacted fill as described in the following paragraphs. Prior to placement of any new fill, the subgrade should be properly prepared. The subgrade should be scarified to a minimum depth of 6 inches, moisture conditioned and compacted to at least 95% of maximum standard Proctor dry density (ASTM 12)-698) at a workable moisture content above optimum value. Soil moisture levels should be preserved (by various methods that can include covering with plastic, watering, etc.) until new fill, pavements or slabs are placed. Placement and compaction of new fill will depend on soil type and its intended purpose. Fill soils used in the building pad area should be placed and compacted as described in the Building Pad Preparation section. Fill used in pavement areas should be placed in 9 inch loose lifts and compacted to at least 95% of maximum standard Pmctor dry density (ASTM D-698) at a workable moisture content above optimum value. Fills placed in general landscape areas should be compacted to at least 90% of maximum standard Proctor dry density (ASTM D-698) at a workable moisture content near optimum value. Imported fills for geneml site grading should be similar to on-site soils, or preferably have a liquid limit less than 50. Upon completion of the filling operations, care should be taken to maintain the subgrade moisture content prior to construction of floor slabs and pavements. If the subgrade becomes desiccated, the affected material should be removed and replaced or these materials should be scarified, moisture conditioned and recompacted. Utility cuts should not be left open for extended periods of time, and should be properly backlllled. Backfilling should be accomplished with properly compacted on-site soils, rather than granular materials. If granular materials are used, a cut-off at the building line is recommended to help prevent water from migrating through the utility trench backfill to beneath the proposed structure. Building Pad Preparation The clay soils encountered at this site are considered active. These active clays can subject the lightly loaded interior floor slabs to movements (due to shrinking and swelling) with fluctuations in their moisture content. Based on test method TEX-124-E in the Texas Department of Transportation (TxDOT) Manual of Testing Procedures and our experience with f~_rnilar soils, we estimate total slab movements on the order of 1½ inches could occur. These movements are based on d~ conditions ECS Project No. 19:4236 Wachovia Bank Coppell, Texas (giving the greatest estimates of potential swell) that can occur prior to construction. The actual movements could be greater if poor drainage, ponded water and/or other unusual sources of moisture are allowed to saturate the soils beneath the structure after construction. Consideration can be given to providing a moisture conditioned soil zone beneath the building area to reduce post-construction soil movements to less than 1 inch. The moisture conditioned soil zone should extend at least 5 feet beyond the building perimeter, and should include any flat work sensitive to vertical movements. The moisture conditioned soil zone can be achieved by reworking the on-site clay soils with proper moisture/density control. The reworked soils should extend to a minimum depth of 3 feet. A minimum thickness of 1 foot of select fill should be installed above the moisture conditioned soil zone immediately following the completion of the reworking process to preserve the moisture content of the clay soils prior to placement of the floor slab. In heu of select fill, consideration can be given to lime- treating the upper 6 inches of the building pad area as described in the Pavement Subgrades section of this report. Reworking of the existing clays is performed to increase the moisture of the clays to a level tbat reduces their ability to absorb additional water that could result in post-construction heave in these soils. The existing clays in the building area should be excavated to the required depth. The exposed clay subgrade should then be scarified to a depth of 6 inches and compacted to a minimum of 92% of standard Proctor maximum dry density at a workable moisture content at least 2% above optimum. The excavated clays can then be replaced to the base of the planned select fill layer in loose lifts less than 9 inches thick and compacted to between 92% and 97% of standard Proctor maximum dw density at a moisture content of 3 to 6% above optimum. In lieu of moisture conditioning the clay soils, removal of two feet (minimum) of the clay soils and replacement with a non-expansive select fill material will reduce the PVR to 1 inch or less. Select fill material (such as clayey sand or very sandy clay that is free of debris and organic matter) should have a Liquid Limit less than 35 and a Plasticity Index between 5 and 15. The non-expansive replacement soil should be placed in loose lifts of 9 inches or less and compacted to at least 95% of its standard Proctor cliy density at a moisture content ranging from -2% to +3% of its optimum value. After completing the filling operations in the building pad area, care should be taken to maintain the subgrade moisture content prior to constructing the floor slab. If the subgrade becomes desiccated, the affected material should be scarified, moistened and recompacted prior to floor slab placement. Preventing large moisture fluctuations in the clay soils beneath the grade-supported floor slab is critical to slab performance. We recommend paving/sidewalks be placed adjacent the structure perimeter to reduce seasonal drying of the moisture conditioned soils near the perimeter of the structure. In'igation of lawn and landscaped areas should be moderate, with no excessive wetting or drying of soils around the perimeter of the structure allowed. Positive drainage away from the structure should also be provided. Trees and bnshes/shrubs planted near the perimeter of the structure can withdraw large ECS Project No. 19:4236 Wachovia Bank Coppell, Texas amounts of water from the soils and should be planted at least their anticipated mature height away from the building. If floor treatments that are sensitive to moisture will be used, a vapor banier of polyethylene sheeting or similar material should be placed beneath the slab to retard moisture migration through the slab. Foundation Recommendations The Stratum I clay soils encountered at this site can subject shallow foundation systems beating on these soils to significant differential movements due to moisture-induced volume changes in these soils. Consideration can be given to supporting the structure on a monolithic slab-on-grade foundation system provided it can withstand anticipated soil-related movements without impairing the structural or operational performance of the structure. Another method of supporting the proposed structure would be straight-sided drilled shafts bearing in shale. Temporary casing will be required for drilled shaft installation. Monolithic Slab Foundation Consideration may be given to supporting the structure on a monolithic slab-on-grade foundation, provided that the Building Pad Preparation recommendations have been followed. An effective plasticity index of 36 is recommended for use in slab design and the following design parameters are recommended for the Post-Tensioning Institute's slab-on-grade design method: EDGE MOISTURE VARIATION Center Lift 5.2 feet Edge Litt 4.2 feet DIFFERENTIAL SWELL Center Lift Edge Lift 1.5 inches 0.8 inch These design parameters assume that positive drainage will be provided away from the structure and moderate irrigation of surrounding lawn and planter areas with no excessive wetting or chying of soils adjacent to the foundations. Greater potential movements could occur with extreme wetting or drying of the soils due to ponding of water, plumbing leaks or lack of irrigation. A net allowable soil beating pressure of 2,500 psf can be used to design grade beams founded on the existing softs or on properly compacted fill extending down to suitable soils. Grade beams should extend at least 18 inches below final adjacent grade to utilize this bearing pressure. Fills should extend a minimum of 3 feet beyond the edge of the foundation and be sloped to drain surface water away from the structure. ECS Project No. 19:4236 Wachovia Bank Coppell, Texas Straight-Sided Drilled Shaft Foundation Straight-sided drilled shafts should bear at a minimum depth of 20 feet (3 feet minimum embedment) into dark gray shale in the building footprint area. The shafts will develop their load canying capacity through a combination of end beating and skin fidction in the shale. We recommend an allowable end bearing capacity of 18,000 psfin the shale. Skin friction values of 1,800 psfmay be used in the shale. Skin fi'iction should only be considered for that portion of the shaft extending into the shale. Properly installed and consaucted drilled shafts beating in the shale could be subject to potential settlements on the order of 1 inch or less. Expansion of the near surface clays with moisture increases can subject the shafts to uplift forces. The magnitude of these forces is difficult to estimate and depends on seveml factors including the in-situ moisture levels at the time of construction and the availability of water. We estimate the magnitude of these forces to be approximately 1,200 psf for the clay soils to a depth of 12 feet below existing grade. The uplift pressure can be reduced to 750 psf over the entire shaR perimeter, if a moisture conditioned soil zone is constructed as described in the Building Pad Preparation section~ Uplift forces must be resisted by the dead load on the shafts and uplift skin fi'iction resistance in the shale. We recommend using an allowable skin friction resistance of 1,400 psfin the shale. The shafts should contain sufficient reinforcing steel continuously throughout the shaft depth to resist anticipated tensile forces. Construction Considerations - Drilled Shafts The use of temporary steel casings will be required for drilled shaft installation. Concrete and steel should be placed as soon as possible after shaft excavations are complete to reduce the potential for seepage problems and detehomtion of the beating surface. The casing should be seated in the shale below any seepage. All water should be removed from the cased excavation before beginning the design rock penetration. A sufficient head of concrete must be maintained in the casing during withdrawal. Installation of individual shafts should be completed in one day. The concrete placed for drilled shafts should have a slump between 5 and 7 inches and should be placed in a manner that prevents it from striking the reinforcing steel and sides of the excavation. We recommend that all drilled shafts be observed by qualified geotechnical personnel, to verify proper shaft installation. ECS Project No. 19:4236 Wachovia Bank Coppell, Texas Grade Beams - Drilled Shafts All grade beams should be supported by the drilled shags and formed with a nominal 6-inch void beneath the beam. This void is provided to isolate the grade beams from the underlying active clays. Cardboard carton forms can be used to create this void. A soil retainer should be provided to help prevent in fill of this void. Soils placed along the exterior of the grade beams should be on-site clay soils that are compacted to at least 95% of their maximum standard Proctor dry density. The clay fill should be compacted at a workable moisture content above its optimum value. The purpose of this clay backfill is to reduce the opportunity for surface water infiltration beneath the structure. Pavement Subgrade All proposed paved areas should be pmofrolled with heavy compaction equipment to attempt to locate any soft or undesirable soils so they can be removed and replaced with properly placed and compacted soils. "[he clay soils present at this site are plastic. The subgrade support value of these clays tends to decrease with increased moisture levels that normally occur beneath area paving. Treatment of the clay soils with hydrated lime will improve their subgrade characteristics to support area paving. Lime treatment of the clay soils is recommended for all clay subgrade areas supporting asphaltic concrete paving. Treatment of the subgrade will also improve performance of Portland cement concrete paving, although concrete paving subject to automobile and light track traffic generally will perform satisfactorily if placed on a prepared (untreated) subgrade. We recommend a minimum of 8%-hydrated lime be used to modify the clay subgrade soils. The hydrated lime should meet the requirements of Item 264 (Type A) in the TxDOT Standard Specifications for Construction of Highways, Streets and Bridges, and should be thoroughly mixed and blended with the upper 6 inches of the clay subgrade (TxDOT Item 260). This mixture should be uniformly compacted to a minimum of 95% of its maximum Standard Proctor dry density (ASTM D- 698) at a moisture content in the range of-2% to +3 as determined by that test. Lime treatment should extend at least 1 foot beyond exposed pavement edges to reduce the effects of shrinkage and associated loss of subgrade support. Pavement Sections If asphaltic concrete pavement is used, we recommend a full depth asphaltic concrete section having a minimm total thickness of 5.0 inches for automobile parking areas and 6.5 inches for drive lanes receiving hght to medium size tracks. A minimum surface course thickness of 2 inches is ECS Project No. 19:4236 Wachovia Bank Coppell, Texas recommended for asphaltic concrete pavements. The asphaltic concrete surface course should conform to Type D and the base course should conform to Type A or B in Item 340 of the TxDOT Standard Specifications. The coarse aggregate in the surface course should be crashed limestone rather than gravel. If Portland cement concrete pavement is used, a minimum thickness of 5.0 inches of reinforced concrete is recommended for parking areas for automobiles and light tracks, and 6.0 inches for drive lanes receiving light to medium size tracks. A minkmum 6.0 inch reinforced concrete section with a lime treated subgrade is recommended in areas receiving occasional heavy tracks. A minimum 8.0 inch reinforced concrete section is recommended for dumpster pickup areas. Concrete with a minimum 28 day compressive strength of 3,500 psi should be used. Drainage Positive drainage should be provided around the entire building penmeter and pavement areas to prevent ponding of water. Pavements, sidewalks or flatwork are preferable to open areas around the building perimeter. Irrigation of lawn and landscaped areas adjacent to the structure should be moderate, with no excessive wetting or crying of soils adjacent to the sUucture. If landscaped areas are provided they should be sloped to drain away from the saucture and landscape borders should allow water to drain freely away from the area. It is preferable that landscape beds immediately adjacent to the structure be self-contained, or a vertical moisture barrier provided between the landscaped area and the building. Closing We recommend that the construction activities be monitored by ECS, Ltd. to provide the necessary overview and to check the suitability of the subgmde soils for supporting the foundations and pavements. We would be most pleased to provide these services. This report has been prepared in order to aid in the evaluation of this property and to assist the architect and/or engineer in the design of this project. The scope is limited to the specific project and locations described herein and our description of the project represents our understanding of the significant aspects relative to soil and foundation characteristics. In the event that any change in the nature or location of the proposed constraction outlined in this report are planned, we should be informed so that the changes can be reviewed and the conclusions of this report modified or approved in writing by the geotechnical engineer. It is recorrnnended that all construction operations dealing with earthwork and foundations be reviewed by an experienced geotechnical engineer to provide information on which to base a decision as to whether the design requirements are fulfilled in the actual construction. If you wish, we would welcome the opporttmity to provide field construction services for you during construction. 10 ECS Project No. 19:4236 Wachovia Bank Coppell, Texas The analysis and recommendations submitted in this report are based upon the data obtained from the soil borings and tests performed at the locations as indicated on the Boring Location Diagram and other information referenced in this report. This report does not reflect any variations, which may occur between the borings. In the performance of the subsurface exploration, specific information is obtained at specific locations at specific times. However, it is a well-known fact that variations in soil and rock conditions exist on most sites between boring locations and also such situations as groundwater levels vary from time to time. The nature and extent of variations may not become evident until the course of construction. If variations then appear evident, after performing on-site observations during the construction period and noting characteristics and variations, a reevaluation of the recommendations for this report will be necessary. 11 APPENDIX Boring Location Diagram Boring Logs Reference Notes For Boring Logs Unified Soil Classification System -- Z B-3 B-1 ~ I I o FITNESS COURT BORING LOCATION DIAGRAM E~ WACHOVLA, - GRANDY'S N)DmON Pmject No.:4236 mmml DENTON TAP ROAD ~ 02/24/05 CLIENT JOB # BORING # SHEET PROJECT NAME ARCHItECT-ENGINEER Wochovio - Grandy's Addition Little Diversified Arch. Consultants Denton Tap Road - Coppell, Texas DESCRIPTION OF MATERIAL ~ -_~ ~ ~ ~ ~ ~'~ ENGLISH UNITS 0 1 ST 12 FILL - SANDY CLAY (CL), brown o.o ~'~ ~s,6 :~asoo: : ~\stiff to very stiff Z0 ,~ : - 4 ST 1~ SANDY C~Y (CL), red-brown and~ 18,5 :~5500: 37 15 E~ 61 gray, trace ferrous nodules, - 5 ST ~ ve~ stiff ~7.0 5~70 SANDY C~Y (CL), light gray and ~ : : calcareous nodules, ve~ stiff : : 10 SANDY C~Y (CL), red-fan and I[ght gray, with gravel, stiff SHALE, dark gray : : 80 _ ~'~ : : END OF BORING ~ 20.0' ~5~ 30 ....... TH[ STR~T]F[C~T[~ L[NES REPE[SENT THE ~PPRDX[~T[ "OUN~ LINES ~[TV[EN SDJL TY~S [N-S]TU THE TE~S[T[DN NAY ~E w~a ~ os~o~s song ~ 02/24/05 CUENT JOB # BOR]NG ~ SHEET Wachovia Corporate Real Estate 4256 8-2 1 oF 1 ~mm~m~')rmD PR0~ECT NA~E ARCH]TECT-ENGINEER Wachovia - Grandy's Addition Little Diversified Arch, Consultants Denton Tap Road - Coppell, lexas 0 1 ST lS FILL - SANDY CLAY (CL), brown 0.o ~ ST 1~ a~d gray-brown, stiff fo ve~ ZO L~.4 :~eo~o : : : 3 ST ~ stiff ~X m,~ .sooo : 4 ST 1~ S~NDY C~Y (CL), dark brown, ~.0 ~7.~ - 5 ST 1~ ~ ve~ stiff ~ ~ S~NDY C~Y (CL), brown and ~.0 gray-brown, trace calcareous - 7 ST 1~ stiff fo ve~ stiff~ 12.4 3380 118 :: 3~ 13 19 ;: 53 C~YEY SAND (SC), red-fan, ~', ;,~ trace gravel, modium dense 9 SS END OF BORING ~ 20.0' : m~ B-41 m~ GC ~N~ ~OD CFA CLIENT JOB ~ BORING # ~i~ST pRO,I~CT NA~E ARCHrrECT-ENGINEER Wachovia - Grandy's Addition Little Diversified Arch. Consultants Denton Tap Road - Coppell, Texas SURFACE ELEVATION 0 1 ST 1~ FILL - CLAY (CH), gray-tan and 0.0 - 2 ST 3.2 red-brown, very stiff - 3 ST 12 SANDY CLAY (CL), dark brown and - 4 ST 12 brown, very stiff fo hord 5 END OF BORING @ 5.0' 10--- 15-- ~0~ :30 -- TF~ STRATIFICATIDN LIN~ZS REPRESENT THE ~PRDXIMATE BOUN]DARY LINES BETWEEN SDIL w~ ~ oe~oss so~s ~ 02/24/05 m~ 8-41 ~ GC ~ ~oD CFA Wachovla Corporate Real Estate 4236 8-4 1 O~ 1 Wachovia - Grandy's Addition Little Diversified Arch. Consultants Denton Tap Road - Coppell, Texas DESCRIPTION OF ~  ~ ENGUSH UN]~ 0 1 ST 18 FILL - SANDY CLAY (CL), 0.0~ ~ ST 1~ red-brown, gray and fan, stiff~ to ve~ stiff 5 ST 1~ SANDY C~Y (CL), dark brown, ~ ~5.~ END OF BORING ~ 5.0' 10~ ~5~ 20-- 25~ 30 ....... w~ ~ o~o~s so~o ~ 02/24/05 ~ B-41 m~ GC ~R~ ~oD CFA REFERENCE NOTES FOR BORING LOGS I. Drilling and Sampling Symbols: SS - Split Spoon Sampler ST - Shelby Tube Sampler RC - Rock Core: NX, BX, AX PM - Pressuremeter DC - Dutch Cone Penetrometer TC - Texas Cone Penetrometer RB - Rock Bit Drilling BS -Bulk Sample of Cuttings PA - Power Auger (no sample) HS - Hollow Stem Auger WS - Wash Sample Standard penetration (blows/ft) refers to the blows per foot of a 140 lb. hammer falling 30 inches on a 2 inch O.D. split spoon sampler, as specified in ASTM D-1586. The blow count is commonly referred to as the N-value. Texas cone penetrometer (blows/in) refers to the penetration of a 3-inch diameter cone after the cone is driven 100 blows with a 140 lb. hammer falling 30 inches. This is a modification of the Texas Department of Transportation test method TEX-132-E that requires a 170 lb. hammer falling 24 inches. II. Correlation of Penetration Resistances to Soil Properties: Relative Density-Sands, Silts Consistency of Cohesive Soils SPT-N Relative Density 0- 3 Very Loose 4- 9 Loose 10-29 Medium Dense 30-49 Dense 50-80 Very Dense Unconfined Compressive Strength. Qp, psf Consistence under 500 Very Soft 500-1,000 Soft 1,000-2,000 Firm 2,000-4,000 Stiff 4,000-8,000 Very Stiff 8,000-16,000 Hard over l&000 V~ry Hard IlL Unified Soil Classification Symbols: GP - Poorly Graded Gravel GW -Well Graded Gravel GM -Silty Gravel GC - Clayey Gravels SP - Poorly Graded Sands SW -Well Graded Sands SM - Silty Sands SC - Clayey Sands ML - Low Plasticity Silts MH -High Plasticity Silts CL - Low Plasticity Clays CH - High Plasticity Clays OL - Low Plasticity Organics OH - High Plasticity Organics CL-ML - Dual Classification (Typical) IV. Water Level Measurement Symbols: WL - Water Level WS - While Sampling WD - While Drilling AB - After Boring Completion BCR - Before Casing Removal ACR - After Casing Removal WCI - Wet Cave In DCI - Dry Cave In The water levels are those water levels actually measured in the borehole at the times indicated by the symbol. The measurements are relatively reliable when augering, without adding fluids, in a granular soil. In clays and plastic silts, the accurate determination of water levels may require several days for the water level to stabilize. In such cases, additional methods of measurement are generally applied. Unified Soil Classification System (ASTM Designation D-2487) Major Division Group Symbol Typical Names Classification Criteria GW Well-graded gravels and gravel- C~ = D6o/D ~0 Greater than 4 ~ ~, sand mixtures, little or no fines = ~ Cz = (D30)2/(D~0xD6o) Between I and 3 ° ~ GP Poorly graded gravels and gravel- t= ~ '~ Not meeting both criteria for GW _~ o~ = sand mixtures, little or no fines ~ ~ ~ ~ GM Silty gravels, gravel-sand-silt ~ . ._~ ~ Atterberg limits plot below "A" line or eq mixtures ~ ~ ~ ~ plasticity index less than 4 ~ GC Clayey gravels, gravel-sand-clay ~ Atterberg limits plot above "A' line '~ ~ ~ mixtures '~ ~ and plasticity index greater than 7 ~ SW Well-graded sands and gravelly o r~ ~o C~ = D60/D~0 Greater than 6 ~ ~ og sands, little or no fines .~ ~ ~ ~ C~ = (D30)~/(D~0xD~0) Between I and 3 ~ m Not meeting both criteria for SW ~ ooz © SP Poorly graded sands and gravelly .~ ~ ~z ~ ~ sands, little or no fines ~ m .~ ~ r~ ~ ~ ~ Atterberg limits plot below "A" line or ~~ ~ ~ ~ SM Silty sands, sand-silt mixtures ~ ~ - ~ plasticity index less than 4 ~ ~ SC Clayey sands, sand-clay mixtures o, ~ and plasticity index greater than 7 ~' ML Inorganic silts, very fine sands, '~ rock flour, silty or clayey fine -~ - *, CL Inorganic clays of low to medium = - plasticity, gravelly clays, sandy ~ ~ ~r ~ clays, silty clays, lean clays ~ ,' ~ OL Organic silts and organic silty e , ~, clays of Iow plasticity ~ MH Inorganic silts, micaceous or ,~ diatomaceous fine sands or silts, ~ .~ ~ elastic silts fi ~ ~ CH Inorganic clays of high plasticitiy, o , Highly organic soils Pt Peat, muck and other highly Fibrous organic matter; will organic soils char, bum, or glow II CLASSIFICATION SYSTEM