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Prologis Park- CS150126GEOTECHNICAL ENGINEERING REPORT PROPOSED SUBARU BTS NEAR NWC OF WEST SANDY LAKE RD AND NORTH COPPELL RD COPPELL, TEXAS Prepared For: ProLogis 2501 North Harwood, Suite 2450 Dallas, Texas 75201 Attention: Mr. Jim McGill January 2015 PROJECT NO. 14-19770 DALLAS | FORT WORTH | AUSTIN | SAN ANTONIO | HOUSTON GEOTECHNICAL ENGINEERING ENVIRONMENTAL CONSULTING CONSTRUCTION MATERIAL TESTING January 26, 2015 Mr. Jim McGill ProLogis 2501 North Harwood, Suite 2450 Dallas, Texas 75201 Re: Geotechnical Engineering Report Proposed Subaru BTS Near NWC of W Sandy Lake Rd and N Coppell Rd Coppell, Texas Rone Project No. 14-19770 Dear Mr. McGill: Submitted herewith are the results of a geotechnical investigation conducted for the referenced project. This investigation was performed in accordance with our proposal P- 20624-14 dated December 10, 2014. This report presents engineering analyses and recommendations for site grading, foundations and pavements. Results of our field and laboratory investigation are submitted in detail in the Appendix section of the report. We appreciate the opportunity to be of service to you on this project. Please contact us if you have any questions or need any additional services. Respectfully Submitted, Xuhui Chang, P.E. Mark D. Gray, P.E. Geotechnical Manager Vice President Texas Engineering Firm License No. F-1572 1.26 . 1 5 TABLE OF CONTENTS Page 1.0 INTRODUCTION........................................................................................................... 1 2.0 PURPOSES AND SCOPE OF STUDY ........................................................................ 1 3.0 FIELD OPERATIONS AND LABORATORY TESTING ............................................... 2 4.0 GENERAL SITE CONDITIONS .................................................................................... 2 4.1 Site Geology .............................................................................................................. 2 4.2 Subsurface Soil Conditions ....................................................................................... 3 4.3 Groundwater ............................................................................................................. 3 5.0 ANALYSIS AND RECOMMENDATIONS .................................................................... 4 5.1 Seismicity Site Class ................................................................................................. 4 5.2 Potential Vertical Soil Movements ............................................................................ 4 5.3 Foundation Recommendations ................................................................................. 5 5.3.1 General Discussion ............................................................................................ 5 5.3.2 Drilled Pier Foundations .................................................................................... 5 5.3.3 Construction Considerations for Drilled Piers .................................................... 6 5.3.4 Grade Beams/Tilt Panels ................................................................................... 6 5.3.5 Interior Floor Slabs ............................................................................................. 7 5.4 Subgrade Treatment ................................................................................................. 7 5.5 Pavement Design Recommendations ...................................................................... 8 5.6 Pavement Subgrade Preparation ........................................................................... 10 5.7 General ................................................................................................................... 12 6.0 GENERAL EARTHWORK RECOMMENDATIONS ................................................... 13 6.1 Site Grading ............................................................................................................ 13 6.2 Preparation of Site .................................................................................................. 13 6.3 Fill Materials ............................................................................................................ 13 6.4 Density Tests .......................................................................................................... 14 7.0 CONSTRUCTION OBSERVATIONS ......................................................................... 14 8.0 REPORT CLOSURE .................................................................................................. 15 APPENDIX A Plate VICINITY MAP…………………………………………………………………………………… .............. …A.1 GEOLOGY MAP…………………………………………………………………………………… ............. .A.2 BORING LOCATION DIAGRAM ......................................................................................................... A.3 LOGS OF BORING ........................................................................................................ A.4 through A.26 KEY TO CLASSIFICATIONS AND SYMBOLS ................................................................................. A.27 UNIFIED SOIL CLASSIFICATION SYSTEM .................................................................................... A.28 SWELL TEST RESULTS (PRELIMINARY INVESTIGATION) .................................................. ……A.29 SWELL TEST RESULTS (CURRENT INVESTIGATION) ......................................................... ……A.30 APPENDIX B Page FIELD OPERATIONS ......................................................................................................................... B-1 LABORATORY TESTING ................................................................................................................... B-2 Project No. 14-19770 Page 1 GEOTECHNICAL ENGINEERING REPORT PROPOSED SUBARU BTS NEAR NWC OF W SANDY LAKE RD AND N COPP ELL RD COPPELL, TEXAS 1.0 INTRODUCTION The proposed project is located near the northwest corner of West Sandy Lake Road and North Coppell Road in Coppell, Texas. We understand the project consists of developing a 300,000 square foot office/warehouse building for Subaru, with associated paved parking and drive areas. Based on 1968 aerial maps. It appears the project site was strip mined in the past. We also understand that fill will be imported from the proposed Building 5 to the subject site to attain the final grade. Based on grading plans provided to Rone, the existing ground surface elevation in the proposed Subaru building ranges from about 477.5 feet on the east side to about 488.5 feet on the west side. The finished floor elevation is proposed to be at 485.5 feet. We anticipate cuts up to 3.5 feet and fills up to 7.5 feet are required to reach the final grade. Rone performed a preliminary geotechnical study for this site (Rone report number 14-18896 dated February 24, 2014). The findings from the preliminary study are included in the report and were used to develop the final geotechnical recommendations. A site vicinity map and geological map are attached as Plates A.1 and A.2, respectively. The general location and orientation of the site are shown on the Boring Location Diagram, Plate A.3, in the Appendix section of this report. 2.0 PURPOSES AND SCOPE OF STUDY The principal purposes of this investigation were to evaluate the general soil and rock conditions at the proposed site and to develop geotechnical recommendations for the design and construction of foundations and pavements. To accomplish its intended purposes, the study was conducted in the following phases: (1) drilled sample borings to evaluate the soil and rock conditions at the boring locations and to obtain soil and rock samples; (2) conducted laboratory tests on selected samples recovered from the borings to establish the pertinent engineering characteristics of the foundation soils; and Project No. 14-19770 Page 2 (3) performed engineering analyses, using field and laboratory data, to develop foundation design criteria. 3.0 FIELD OPERATIONS AND LABORATORY TESTING In addition to the four borings (B-1 through B-4) completed during the preliminary study, soil conditions were determined by 19 additional borings (B-5 through B-23). Borings B-5 through B-15 were drilled to depths of about 30 feet in the proposed Subaru BTS building and future expansion areas, and borings B-16 through B-23 were advanced to depths of about 5 feet in the borrow site (Building 5). The preliminary borings (B-1 through B-4) and the additional borings (B-5 through B-23) were drilled in February, 2014 and January, 2015, respectively, and their locations are shown on Plate A.3. Sample depth, description of soils, and classification (based on the Unified Soil Classification System) are presented on the Log s of Boring, Plates A.4 through A.26. Keys to terms and symbols used on the logs are shown on Plates A.27 and A.28. As mentioned previously, the site appeared to be strip mined in the 1960s and fill could be pre sent at this site. To better define thickness, quality and composition of possible fill at this site, a total of 26 test pits were excavated during our preliminary investigation. Seven of those test pits were performed in or near the proposed S ubaru building area. The seven test pit locations are shown on the boring location diagram. Laboratory soil tests were performed on selected sa mples recovered from the borings to confirm visual classification and determine the pertinent engineering properties of the soils encountered. Classification test results are presented on the Logs of Boring. Swell tests were performed on selected clay samples and the results are tabulated and presented in the Appendix section of this report on Plates A.29 (preliminary investigation) and A.30 (current investigation). Descriptions of the procedures used in the field and laboratory phases of this stu dy are presented in the Appendix of this report. 4.0 GENERAL SITE CONDITIONS 4.1 Site Geology Based on published surface geology maps and our borings, this site appears to be located on Fluviatile Terrace Deposits underlain by the Woodbine Formation. Fluviatile Terrace Deposits generally consist of gravel, sand, silt, and clay. The Woodbine formation generally consists of sand, Project No. 14-19770 Page 3 clays, sandstones and shales. Dense and irregular shaped masses of hard sandstone occur at random throughout the formation. It is often difficult, if not impossible, to trace a particular bed for any distance. Water is found at various levels in the formation, some as perched tables in sand lenses. 4.2 Subsurface Soil Conditions The various strata and their approximate depths and thickness are shown on the boring logs. Stratification boundaries on the boring logs represent the approximate location of changes in soil and rock types; in-situ, the transition between materials may be gradual. A brief summary of the stratigraphy indicated by the borings is given below. Building borings (B-1 through B-15) generally encountered light brown to dark brown and gray, lean clay (CL), fat clay (CH), silty sand (SM), clayey sand (SC), silty clayey sand (SC-SM) to depths of about 7 to 19 feet below existing grades, followed by light brown and gray shale and sandstone to boring termination depths of about 25 to 30 feet. The borings in the borrow areas (B-16 through B-23) generally encountered the similar soils as the building borings. The test pits generally encountered sandy clay, clayey sand, sand and gravel. No debris, trash or other unsuitable materials were observed to the test pit termination depths of about 5.5 to 12.5 feet. Based on our visual observation of the test pit observations, many pockets of on-site soils appear to be suitable to use as select fill. The Plasticity Index of the samples tested varied from non-plastic up to 35, indicating very low to high soil plasticity. A high Plasticity Index is generally associated with a high potential for the active clay soils to shrink and swell with changes in moisture content. 4.3 Groundwater The borings were advanced using auger drilling and intermittent sampling methods in order to observe groundwater seepage levels. Groundwater measurements are shown near the top of the boring logs and are also summarized in the following table. Boring No. Depth to Groundwater Water (feet) During Drilling At Boring Completion B-1 24 18 Project No. 14-19770 Page 4 Boring No. Depth to Groundwater Water (feet) During Drilling At Boring Completion B-2 6 9 B-4 12 10 B-6 13 Not encountered B-7 16 24 B-9 25.5 28 B-12 23 30 Water seepage was not observed in the remaining borings and the se boreholes appeared dry at boring completion. It is difficult to accurately predict the magnitude of subsurface water fluctuations that might occur based upon short-term observations. Groundwater can be encountered at vary depths, particularly during wet periods of the year. Groundwater should be anticipated during the construction phase of this project. Groundwater levels should be expected to fl uctuate throughout the year with variations in precipitation, runoff, and the water levels in nearby surface water features. 5.0 ANALYSIS AND RECOMMENDATIONS 5.1 Seismicity Site Class The site class for seismic design is based on several factors that incl ude soil profile (soil or rock), shear wave velocity, density, relative hardness, and strength, averaged over a depth of 100 feet. The borings for this project did not extend to a depth of 100 feet; therefore, we assumed the soil conditions below the depth of the borings to be similar to those encountered at the termination depth of the borings. Based on Section 1613.5.2 of the 2012 International Building Code, we recommend using Site Class C (stiff soil/soft rock) for seismic design. 5.2 Potential Vertical Soil Movements Potential Vertical Movement calculations were performed in general accordance with the Texas Department of Transportation (TxDOT) Method 124-E. The TxDOT 124-E method is empirical and is based on the Atterberg limits and moisture conten t of the subsurface soils. Swell test results were also used in the estimation of the PVR. The Potential Vertical Rise (PVR) calculated using the TxDOT method ranges from about 1 to 3 inches based on in-situ soil being at a dry antecedent condition, existing site grades at the time of our drilling and the depth of the active soil zone at 12 feet . At the time of drilling, the soils at the Project No. 14-19770 Page 5 borings were generally in a dry to slightly moist condition. Results of free swell tests indicated the PVR could be up to 4 inches. 5.3 Foundation Recommendations 5.3.1 General Discussion Based on conditions encountered at the time of our investigation and our understanding of the project, the proposed building can be supported on auger-excavated, straight shaft, cast-in-place concrete pier foundations with on-grade interior slabs, provided subgrade treatment is performed to reduce the PVR to more tolerable levels (1 inch). Recommendations for foundations are presented below. 5.3.2 Drilled Pier Foundations Drilled pier foundations can be utilized to support the structural loads of the proposed structures. Auger-excavated, straight shaft, steel reinforced, cast-in-place concrete piers, founded in the light brown and gray shale and sandstone (encountered at depths of about 7 to 19 feet below the existing grade in our borings, elevations ranging from 466 to 474.5 feet, generally within 466 to 470 feet) may be used for the structures. The sandstone and shale bedrock was generally encountered at deeper depths ranging from elevations 458.5 to 462 feet (Borings B-2, 14, and 15) in the future expansion area located east of the proposed Subaru building. The piers should have a minimum penetration of 3 feet into the light brown and gray sandstone or shale. These piers may be designed using a net allowable end bearing pressure of 15,000 pounds per square foot (psf). An allowable skin friction of 2,250 psf may be used for the portion of the pier extended below a minimum penetration of 3 feet into the light brown and gray sandstone or shale. Foundation settlement for drilled piers on the gray shale should be less than ½ inch. Based on a finished floor elevation of 485.5 feet and average bearing strata elevation of about 467 feet, the average depth to start of penetration is on the order of 21 feet. We would expect 5 to 10 feet of penetration resulting in an average pier depth of 28 feet. The uplift force on the piers due to swelling of the active clays can be approximated by assuming a uniform uplift pressure of 1,800 psf acting over the perimeter of the shaft to a depth of 12 feet below final pad elevation. The uplift pressure may be reduced to 800 psf acting over the perimeter of the shaft within re-worked, moisture-conditioned soils. Uplift forces should not be developed on piers penetrating through materials classified as select fill. The shafts should contain sufficient full length reinforcing steel to resist uplift forces. The uplift force can be resisted by the dead load on the shafts plus the allowable skin friction resistance in the portion of the shaft embedded in the sandstone and shale described above. Project No. 14-19770 Page 6 Based on anticipated loads, we recommend a minimum shaft size of 18 inches. Adjacent piers should have a minimum center-to-center spacing of 3 shaft diameters (based on diameter of the larger shaft) for uplift design purposes. Closer pier spacing could result in reduced uplift resistance. We should be contacted to review closer pier spacing on a case by case basis. 5.3.3 Construction Considerations for Drilled Piers The construction of all piers should be observed as a means to verify compliance with design assumptions and to confirm: 1) the bearing stratum; 2) the minimum penetration into the light brown and gray sandstone or shale; 3) the removal of all smear zones and cuttings; 4) that groundwater seepage, when encountered, is correctly handled; and 5) that the shafts are vertical (within the acceptable tolerance). Groundwater seepage was observed at depths ranging from 6 to 30 feet in some of the borings during the drilling operations and the possibility of encountering groundwater seepage should be considered high during pier drilling. Temporary steel casings will be required to control seepage and caving of variable materials and conditions. The casing should be seated in the sandstone or shale below the seepage, and all water should be removed from the shaft excavation before beginning the design rock penetration. Any portion of the shale above the bottom of the casing should be neglected in the design penetration. Concrete should be placed immediately after the excavation has been completed. In no event should a pier excavation be allowed to remain open for more than 8 hours. Concrete should have a slump of 5 to 7 inches, and should not be allowed to strike the shaft sidewall or steel reinforcement during placement. 5.3.4 Grade Beams/Tilt Panels Grade beams/tilt panels should be structurally connected to the top of the pi ers. A minimum void space of 8 inches should be provided beneath the beams/tilt panels and the underlying soil between piers. The void space can be reduced to 4 inches if subgrade treatment is completed as presented in this report. This void space allows movement of the soils below the grade beams/tilt panels without distressing the structure. The excavation in which the void box lays must remain dry. In addition, backfill material must not be allowed to enter the void area below the grade beams/tilt Project No. 14-19770 Page 7 panels, since this reduces the void space. These recommendations also apply to interior pile caps. Typically, a soil retainer in the form of a thin pre-cast panel or pieces of wood is placed along the outside edge of the grade beams/tilt panels to prevent the aforementioned soil intrusion. On-site soil then may be placed against the sides of the grade beams/tilt panels. 5.3.5 Interior Floor Slabs If some movement can be tolerated, the floor slab can be ground supported provided subgrade treatment is completed as described in Section “5.4 Subgrade Treatment”. The floor slab may consist of an independent slab not rigidly connected to the building walls, columns or foundations. If the floor slab is rigidly connected to the building walls, a hinge crack may develop in the slab parallel to the wall at a short distance from the wall. The severity of the cracking will depend on the amount of movement that occurs, the rigidity of the floor slab and the rigidity of the connection. In extreme cases, excessive movement and cracking of walls and foundations could occur if the connection to the floor slab is sufficiently rigid. A moisture barrier should be used beneath the interior floor slab in areas where floor coverings will be utilized or in areas that are sensitive to moisture. 5.4 Subgrade Treatment As mentioned earlier, swell tests indicate potential ground movement up to 4 inches is possible at this site. In order to reduce the PVR to more tolerable levels (about 1 inch), subgrade treatment of the building pad subgrade will be required. Subgrade treatment should consist of removing the active subgrade soils to a depth of 10 feet below the final pad elevation. The removed clays can then be replaced with moisture and density control to within 1 foot of final pad elevation and capped with 1 foot of select fill material. Water pressure injection is generally considered as an alternative to mechanically removing and reworking of the active subgrade soils. However, due to the presence of significant sand layers/seams, water pressure injection does not appear practical at this site. Moisture conditioning of clays to be used as fill should be performed to increase the moisture of the clays to a level that reduces their ability to absorb additional water that could result in post-construction heave in these soils. The subgrade should be excavated to the depth of 10 feet below the final pad elevation. Any deleterious materials or rock fragments greater than 4 inches in diameter encountered within the soils should be removed. The subgrade to receive moisture-conditioned clay should be scarified to a depth of 6 inches, and compacted to 92 to 96 percent of the material’s Standard Proctor dry density (ASTM D698) at a workable moisture content at least 3 percentage points above optimum. Project No. 14-19770 Page 8 The clays to be used as fill can then be placed in loose lifts less than 10 inches, compacted to a similar density and moisture content to within 1 foot of final grade. The remaining 1 foot of material placed should consist of select fill as described below. Select fill should consist of a sandy clay or clayey sand with a liquid limit less than 35 and plasticity index (PI) between 5 and 15. The fill should be placed in loose lifts less than 10 inches thick, and compacted to a minimum of 95 percent of the material’s maximum standard Proctor dry density (ASTM D698). The moisture content of the select fill should be within 2 percentage points of the optimum moisture content as determined by the standard Proctor test. Lime-treated, on-site soils may also be used as the select fill cap, provided the PI of the material meets the specifications for select fill. We anticipate 7 to 10 percent lime may be required. The actual percentage of lime should be determined once soils have been stockpiled and sampled. Crushed limestone or concrete can also be used as select fill. The crushed limestone or concrete should meet the requirements of TxDOT Standard Specifications Item 247, Grade 3, Type A. The material should be compacted in maximum 9-inch loose lifts to a minimum of 95 percent of the material’s Standard Proctor maximum dry density, at a moisture content of -2 to +2 percentage points of optimum. The select fill should not extend beyond the perimeter beam and it should be placed over the moisture- conditioned clays immediately after the moisture-conditioning process is complete. The subgrade should be kept moist prior to slab construction. Moisture conditioned clay fill should be monitored and tested on a full-time basis by Rone Engineers to confirm conditions are as anticipated and to confirm the fill is placed with the proper moisture content and degree of compaction. Density tests should be performed on each lift of fill placed. 5.5 Pavement Design Recommendations When designing proposed pavement sections for driveways and parking areas, subgrade conditions must be considered along with expected traffic use/frequency, pavement type, and design period. For this project, traffic loading and frequency conditions were assumed for various conditions as no specific traffic information was provided. The following information and assumptions were used in our analysis: Project No. 14-19770 Page 9 (1) 45,000 total design equivalent single axle load (ESAL) repetitions for parking areas subjected to automobiles and light trucks; (2) 100,000 total design ESAL repetitions for drive/fire lanes subjected to automobile, light trucks and fire trucks; (3) 500,000 total design ESAL repetitions for heavy duty pavements subjected to semi- tractor trailers and dumpster trucks, or equivalent; (4) A concrete modulus of rupture of 530 psi; (5) A design life of 20 years; (6) Initial serviceability, po, of 4.5 and a terminal serviceability, pt, of 2.0 for concrete pavements; (7) Reliability, 85 percent (8) Standard deviation, 0.35 (9) Load transfer (“J” factor), 3.1 (doweled concrete pavement with edge support) (10) Drainage coefficient, 1.0 (11) A k-value of 100 pci for subgrade consisting of clay so ils and 150 pci for lime-stabilized subgrade. The pavement thickness determinations were performed in accordance with the “AASHTO Guide for the Design of Pavement Structures (current edition)” guidelines. The minimum pavement sections are presented in the table below. These pavement sections are estimates based on assumed traffic volumes. A more precise design can be made with detailed traffic loading information. Traffic Use Design ESAL Count Portland Cement Concrete (PCC) Thickness (inches) Parking Areas for Autos and Light Trucks 45,000 5 Drive Lanes for Autos and Light Trucks/Fire Lanes 100,000 6 Light Semi-Truck Traffic/Dumpster Areas 500,000 7 Project No. 14-19770 Page 10 Concrete with a minimum 28 day compressive strength of 3,500 pounds per square inch should be used. As a minimum, reinforcing steel should consist of #3 bars spaced at a maximum of 18 inches on center in each direction. Lime stabilization of the pavement subgrade is recommended for PCC pavements subjected to heavy truck traffic (7 inch pavement section). In small localized areas (dumpster pads, etc.), it may not be practical to perform lime stabilization . In these areas, the concrete thickness may be increased by one (1) inch and lime stabilization omitted. Increased periodic maintenance (i.e. sealing of cracks/joints) is critical to the long -term performance of the pavement in areas without subgrade stabilization. Lime stabilization will improve pavement performance for the 5- and 6-inch section; however, it is not required. Periodic maintenance (i.e. sealing of cracks and joints) should be performed to prevent water intrusion into the underlying clay subgrade. The pavement surface should be contoured such that surfac e water drains off and away from the pavement or into inlets. Water allowed to pond on or adjacent to pavement surfaces could saturate the subgrade soils leading to premature pavement failure. Pavement recommendations are based on the assumed loading conditions and commonly accepted design procedures that should provide satisfactory performance for the design life of 20 years for the assumed traffic loadings. The concrete pavement should have between 4 and 6 percent entrained air. Hand-placed concrete should have a maximum slump of six inches. A sand-leveling course should not be permitted beneath pavements. All steel reinforcement, dowel spacing/diameter, and pavement joints should conform to applicable city standards. 5.6 Pavement Subgrade Preparation All topsoil, vegetation, and any unsuitable materials should be removed. The pavement subgrade should be proofrolled with a fully loaded tandem axle dump truck or similar pneumatic-tire equipment to locate areas of loose subgrade. In areas to be cut, the proofroll should be performed after the final grade is established. In areas to be filled, the proofroll should be performed prior to placement of engineered fill and after subgrade construction is complete. Areas of loose or soft subgrade encountered in the proofroll should be removed and replaced with engineered fill, or moisture conditioned (dried or wetted, as needed) and compacted in place. Grading and compaction of pavement subgrade should follow the recommendations in the “General Earthwork recommendations” section. The final grades must be such that drainage is facilitated, Project No. 14-19770 Page 11 and access of surface water to the subgrade materials is prevented. The existing soils are plastic and can undergo some volume change when subjected to moisture variations. If the moisture contents of these upper soils reduce, they may shrink and cracks may develop. If the moisture content of these materials increases, they could swell and lose strength. Shrinkage, swelling, or strength loss could be detrimental to the proper function of the pavement. Lime stabilization will provide more uniform subgrade support and improve these soil's strength characteristics. If lime stabilization is used, we recommend a minimum of 7 percent lime (by dry soil weight) to a depth of 6 inches. However, the actual percentage lime required should be determined during site development by completing a lime series test. Lime stabilization should be performed in accordance with Item 260, current Standard Specifications for Construction o f Highways, Streets, and Bridges, Texas Department of Transportation (TxDOT) or applicable standards. Clayey sand, sandy clay or sandy soils will not benefit from lime treatment. In these areas, cement treatment may be necessary. Portland cement treatment should be in accordance with TxDOT Item 275, "Standard Specifications for Construction and Maintenance of Highways, Streets, and Bridges." It is anticipated that 5 percent by dry weight of Portland cement will be required to stabilize the clayey sand or sandy clay subgrade to a depth of 6 inches. The cement treated subgrade should be thoroughly mixed and compacted to 95 percent of standard Proctor density at optimum moisture content to + 3 percent. Compaction of the treated subgrade should be performed no later than 4 hours after adding and mixing the cement into the subgrade. The actual percentage of cement required should be confirmed in the field by collecting soil samples during construction once pavement subgrade elevation is attained. A cement series should be performed on the sample collected and the results should be used to determine the actual percentage of cement required. The amount and type of stabilization should be determined when the site is grad ed and the pavement subgrade exposed. The readers should understand that lime /cement stabilizing the upper 6 inches of the subgrade soils will not reduce the shrinking and swelling of the subgrade, which normally occurs with the seasonal moisture fluctuations. Therefore, some differential vertical movements of the pavements should be expected. Water can be introduced beneath the pavement through granular materials used for aggregate bases and utility line embedment, and can cause differential movement in the pavement. Aggregate base or a granular leveling course should not be used beneath pavements, and all utilities should Project No. 14-19770 Page 12 have clay plugs substituted for granular embedment material at the edges of the pavement to reduce the risk of moisture access and possible swelling. 5.7 General All grade supported slabs, outward swinging doors, outside stairs, etc. should be designed to accommodate anticipated potential movements at this site as presented at t he beginning of this section. Every attempt should be made to limit the extreme wetting or drying of the subsurface soils because swelling and shrinkage of these soils will result. Standard construction practices of providing good surface water drainage should be used. A positive slope of the ground away from any foundation should be provided. Also, ditches or swales should be provided to carry the run -off water both during and after construction. Lawn areas should be watered moderately, without allowi ng the clay soils to become too dry or too wet. Roof runoff should be collected by gutters and downspouts, and should discharge away from the building. Backfill for utility lines or along the perimeter beams should consist of site -excavated soil. If the backfill is too dense or too dry, it will swell and a mound will form along the trench line. If the backfill is too loose or too wet, it will settle and a sink will form along the trench line. Backfill should be compacted as recommended in the section titled “General Earthwork Recommendations” below. If granular material is used for embedment in utility trenches, we recommend placing a clay plug, as a replacement for the granular embedment, at the location where the city line is located, at the location where the utility enters the structure and at other connections. The intent is to stop any free moisture from passing through the granular embedment and entering the soil beneath the structures. Root systems from trees and shrubs can draw a substantial amount of water from the clay soils at this site, causing the clays to dry and shrink. This could cause settlement beneath grade-supported slabs such as foundation slabs, walks and paving. Trees and large bushes should be located a distance equal to at least one-half their anticipated mature height away from grade slabs. All excavations should be sloped, shored, or shielded in accordance with OSHA requirements. Project No. 14-19770 Page 13 6.0 GENERAL EARTHWORK RECOMMENDATIONS 6.1 Site Grading Site grading operations, where required, should be performed in accordance with the recommendations provided in this report. The site grading plans and construction should strive to achieve positive drainage around all sides of the proposed buildings. Inadequate drainage around structures built on-grade will cause excessive vertical differential movements to occur. 6.2 Preparation of Site Preparation of the site for construction operations should include the removal and proper disposal of all obstructions that would hinder preparation of the site for construction. These obstructions should include all abandoned structures, foundations, debris, water wells, septic tanks and loose material. It is the intent of these recommendations to provide for the removal and disposal of all obstructions not specifically provided for elsewhere by the plans and specifications. All concrete, trees, stumps, brush, abandoned structures, roots, vegetation, rubbish and any other undesirable matter should be removed and disposed of properly . It is the intent of these recommendations to provide a loose surface with no features that would tend to prevent uniform compaction by the equipment to be used. Areas to be filled should be disced or bladed to a minimum depth of 6 inches until uniform and free from large clods, brought to a moisture content within 2 percent of the optimum moisture value, and compacted to at least 95 percent of maximum dry density in accordance with ASTM D698. 6.3 Fill Materials Materials to be used for general site fill should consist of on-site material approved by the Soils Engineer. Imported general site fill should have a liquid limit less than 60 and should be approved by the Soils Engineer. There should be no roots, vegetation or any other undesirable matter in the soil and no rocks larger than 4 inches in diameter. The fill material should be placed in level, uniform layers, which, when compacted, should have a moisture content and density conforming to the stipulations called for herein. Each layer should be thoroughly mixed during spreading to provide uniformity of the layer. The fill thickness should not exceed 10-inch loose lifts. Project No. 14-19770 Page 14 Prior to and in conjunction with the compacting operation, each layer should be brought to the proper moisture content as determined by ASTM D 698. We recommend the clay soils be moisture conditioned to a moisture content that is between optimum and 4 percentage points above optimum. After each layer has been properly placed, mixed and spread, it should be thoroughly compacted to between 95 and 100 percent of Standard Proctor Density as determined by ASTM D698. 6.4 Density Tests Field Density tests should be made by the Soils Engineer or his representative. Density tests should be taken in each layer of the compacted material below the disturbed su rface. If the materials fail to meet the density specified, the course should be reworked as necessary to obtain the specified compaction. 7.0 CONSTRUCTION OBSERVATIONS In any geotechnical investigation, the design recommendations are based on a limited amount of information about the subsurface conditions. In the analysis, the geotechnical engineer must assume the subsurface conditions are similar to the conditions encountered in the boring. However, during construction quite often anomalies in the sub surface conditions are revealed. Therefore, it is recommended that Rone Engineering Services , Ltd. be retained to observe earthwork and foundation installation and perform materials evaluation and testing during the construction phase of the project. This enables the geotechnical engineer to stay abreast of the project and to be readily available to evaluate unanticipated conditions, to conduct additional tests if required and, when necessary, to recommend alternative solutions to unanticipated conditions . Until these construction phase services are performed by the project geotechnical engineer, the recommendations contained in this report on such items as final foundation bearing elevations, final depth of undercut of expansive soils for non -expansive earth fill pads, and other such subsurface -related recommendations should be considered as preliminary. It is proposed that construction phase observation and materials testing commence by the project geotechnical engineer at the outset of the project. Ex perience has shown that the most suitable method for procuring these services is for the owner to contract directly with the project geotechnical engineer. This results in a clear, direct line of communication between the owner and the owner's design engineers, and the geotechnical engineer. Project No. 14-19770 Page 15 8.0 REPORT CLOSURE The analyses, conclusions and recommendations contained in this report are based on site conditions as they existed at the time of the field investigation and further on the assumption that the exploratory boring is representative of the subsurface conditions throughout the site; that is, the subsurface conditions everywhere are not significantly different fro m those disclosed by the boring at the time it was completed. If during construction, different subsurface conditions from those encountered in our boring are observed, or appear to be present in excavations, we must be advised promptly so that we can review these conditions and reconsider our recommendations where necessary. If there is a substantial lapse of time between submission of this report and the start of the work at the site, if conditions have changed due either to natural causes or to construction operations at or adjacent to the site, or if structure locations, structural loads or finish grades are changed, we urge that we be promptly informed and retained to review our report to determine the applicability of the conclusions and recommendations, considering the changed conditions and/or time lapse. Further, it is urged that Rone Engineering Services, Ltd. be retained to review those portions of the plans and specifications for this particular project that pertain to earthwork and foundations as a means to determine whether the plans and specifications are consistent with the rec ommendations contained in this report. In addition, we are available to observe construction, particularly the compaction of structural fill, or backfill and the construction of foundations as recommended in the report and such other field observations as might be necessary. This report has been prepared for the exclusive use of the client and their designated agents for specific application to design of this project. We have used that degree of care and skill ordinarily exercised under similar conditions by reputable members of our profession practicing in the same or similar locality. No warranty, expressed or implied, is made or intended. APPENDIX A 480.0 472.0 467.0 463.0 460.0 17 14 NP 4.50 2.75 4.5+ N=20 N=25 N=36 N=33 100/5'' N=50/5.0 12 17 10 8 9 11 7 21 35 22 NP SANDY FAT CLAY (CH) - brown and dark brown SANDY LEAN CLAY (CL) - brown, light brown and gray SILTY SAND (SM) - light brown SANDSTONE - light brown SHALE - gray Boring Terminated at 25 Feet 67 60 14 52 36 NP CFA B- 1 RE C % 5 10 15 20 25 Surface Elevation Sy m b o l 2-5-14 Sa m p l e s Water Observations (feet) Completion Date LOG OF BORING NO. Pl a s t i c Li m i t , % Completion Depth Project No. 14-18896 Building A Proposed Prologis Park Coppell, Texas Pa s s i n g N o . 2 0 0 Si e v e , % Dr y U n i t W e i g h t pc f Pl a s t i c i t y In d e x Li q u i d Li m i t , % Pe n e t r o m e t e r Re a d i n g , T S F SP T - B l o w s / F o o t TC P - B l o w s / I n c h 485.0 De p t h , F t . Plate A.4 Location B- 1 Boring No. Un c o n f i n e d Co m p r e s s i o n ps f Type Stratum Description Mo i s t u r e Co n t e n t , % 25.0' While Drilling 24 18At Boring Completion End of Day After Boring Completion RO N E E N G I N E E R I N G L O G S - 1 1 4 - 1 8 8 9 6 . G P J R O N E . G D T 1 / 2 6 / 1 5 475.0 473.0 469.0 464.0 458.5 452.0 17 NP 1.00 0.50 N=27 N=26 N=70 N=50/2.5" N=50/3.0" 8 14 19 23 17 14 14 20 6 NP SANDY CLAY (CL) - brown SANDY CLAY (CL) - dark brown and light brown SILTY CLAYEY SAND (SC-SM) - light brown SILTY SAND (SM) - light brown SHALEY CLAY (CH) - gray SHALE - gray Boring Terminated at 25 Feet 41 27 23 NP CFA B- 2 RE C % 5 10 15 20 25 Surface Elevation Sy m b o l 2-4-14 Sa m p l e s Water Observations (feet) Completion Date LOG OF BORING NO. Pl a s t i c Li m i t , % Completion Depth Project No. 14-18896 Building A Proposed Prologis Park Coppell, Texas Pa s s i n g N o . 2 0 0 Si e v e , % Dr y U n i t W e i g h t pc f Pl a s t i c i t y In d e x Li q u i d Li m i t , % Pe n e t r o m e t e r Re a d i n g , T S F SP T - B l o w s / F o o t TC P - B l o w s / I n c h 477.0 De p t h , F t . Plate A.5 Location B- 2 Boring No. Un c o n f i n e d Co m p r e s s i o n ps f Type Stratum Description Mo i s t u r e Co n t e n t , % 25.0' While Drilling 6 9At Boring Completion End of Day After Boring Completion RO N E E N G I N E E R I N G L O G S - 1 1 4 - 1 8 8 9 6 . G P J R O N E . G D T 1 / 2 6 / 1 5 486.5 480.5 475.5 467.5 15 14 2.75 4.5+ 4.5+ N=38 N=41 N=50/3.0" 100/3.75'' 100/3'' 14 11 10 10 15 13 26 28 CLAYEY SAND (SC) - brown, dark brown and reddish brown, with sand CLAYEY SAND (SC) - brown and gray SANDSTONE - light brown SHALE - gray Boring Terminated at 25 Feet 42 48 41 42 CFA B- 3 RE C % 5 10 15 20 25 Surface Elevation Sy m b o l 2-4-14 Sa m p l e s Water Observations (feet) Completion Date LOG OF BORING NO. Pl a s t i c Li m i t , % Completion Depth Project No. 14-18896 Building A Proposed Prologis Park Coppell, Texas Pa s s i n g N o . 2 0 0 Si e v e , % Dr y U n i t W e i g h t pc f Pl a s t i c i t y In d e x Li q u i d Li m i t , % Pe n e t r o m e t e r Re a d i n g , T S F SP T - B l o w s / F o o t TC P - B l o w s / I n c h 492.5 De p t h , F t . Plate A.6 Location B- 3 Boring No. Un c o n f i n e d Co m p r e s s i o n ps f Type Stratum Description Mo i s t u r e Co n t e n t , % 25.0' While Drilling not encountered not encounteredAt Boring Completion End of Day After Boring Completion RO N E E N G I N E E R I N G L O G S - 1 1 4 - 1 8 8 9 6 . G P J R O N E . G D T 1 / 2 6 / 1 5 470.0 464.5 453.0 14 17 4.25 4.5+ 3.50 2.75 0.25 100/5" 100/6.75'' 100/6'' 15 13 15 14 19 23 2 CLAYEY SAND (SC) - brown SILTY SAND (SM) - light brown SANDSTONE - gray Boring Terminated at 25 Feet 44 16 37 19 CFA B- 4 RE C % 5 10 15 20 25 Surface Elevation Sy m b o l 2-14-14 Sa m p l e s Water Observations (feet) Completion Date LOG OF BORING NO. Pl a s t i c Li m i t , % Completion Depth Project No. 14-18896 Building A Proposed Prologis Park Coppell, Texas Pa s s i n g N o . 2 0 0 Si e v e , % Dr y U n i t W e i g h t pc f Pl a s t i c i t y In d e x Li q u i d Li m i t , % Pe n e t r o m e t e r Re a d i n g , T S F SP T - B l o w s / F o o t TC P - B l o w s / I n c h 478.0 De p t h , F t . Plate A.7 Location B- 4 Boring No. Un c o n f i n e d Co m p r e s s i o n ps f Type Stratum Description Mo i s t u r e Co n t e n t , % 25.0' While Drilling 12 10At Boring Completion End of Day After Boring Completion RO N E E N G I N E E R I N G L O G S - 1 1 4 - 1 8 8 9 6 . G P J R O N E . G D T 1 / 2 6 / 1 5 485.5 474.5 457.5 14 14 2.00 4.5+ 4.5+ 4.5+ 4.5+ 100/1'' 100/2'' 100/3.5'' 100/3'' 15 11 11 10 10 11 17 18 18 10 14 25 SANDY LEAN CLAY (CL) - brown to light brown LEAN CLAY (CL) - light brown to brown SANDSTONE - gray, with shale layers Boring Terminated at 30 feet. 63 81 28 39 CFA B- 5 RE C % 5 10 15 20 25 30 Surface Elevation Sy m b o l 1-12-15 Sa m p l e s Water Observations (feet) Completion Date LOG OF BORING NO. Pl a s t i c Li m i t , % Completion Depth Project No. 14-19770 Proposed Prologis Park One Twenty One - Subaru BTS Warehouse Coppell, Texas Pa s s i n g N o . 2 0 0 Si e v e , % Dr y U n i t W e i g h t pc f Pl a s t i c i t y In d e x Li q u i d Li m i t , % Pe n e t r o m e t e r Re a d i n g , T S F SP T - B l o w s / F o o t TC P - B l o w s / I n c h 487.5 De p t h , F t . Plate A.8 Location B- 5 Boring No. Un c o n f i n e d Co m p r e s s i o n ps f Type Stratum Description Mo i s t u r e Co n t e n t , % 30.0' While Drilling Not Encountered Not Encountered Not Measured At Boring Completion End of Day After Boring Completion RO N E E N G I N E E R I N G L O G S - 1 1 4 - 1 9 7 7 0 . G P J R O N E . G D T 1 / 2 6 / 1 5 466.0 451.5 449.5 14 14 2.00 4.5+ 4.5+ 4.5+ 4.5+ N=50/3" N=50/2" N=50/4" 100/2.25'' 16 8 9 12 12 25 17 21 20 22 LEAN CLAY (CL) - dark brown, with sand SANDSTONE - gray, with shale layers SHALE - gray Boring Terminated at 30 feet. 78 76 34 36 CFA B- 6 RE C % 5 10 15 20 25 30 Surface Elevation Sy m b o l 1-8-15 Sa m p l e s Water Observations (feet) Completion Date LOG OF BORING NO. Pl a s t i c Li m i t , % Completion Depth Project No. 14-19770 Proposed Prologis Park One Twenty One - Subaru BTS Warehouse Coppell, Texas Pa s s i n g N o . 2 0 0 Si e v e , % Dr y U n i t W e i g h t pc f Pl a s t i c i t y In d e x Li q u i d Li m i t , % Pe n e t r o m e t e r Re a d i n g , T S F SP T - B l o w s / F o o t TC P - B l o w s / I n c h 479.5 De p t h , F t . Plate A.9 Location B- 6 Boring No. Un c o n f i n e d Co m p r e s s i o n ps f Type Stratum Description Mo i s t u r e Co n t e n t , % 30.0' While Drilling 13 Not Encountered Not Measured At Boring Completion End of Day After Boring Completion RO N E E N G I N E E R I N G L O G S - 1 1 4 - 1 9 7 7 0 . G P J R O N E . G D T 1 / 2 6 / 1 5 471.0 448.0 15 14 3.00 3.00 1.50 4.5+ N=50/4.25" N=50/5.75" 100/2.5'' N=50/4.75" 100/2.75'' 100/1.5'' 11 11 8 8 10 7 25 21 23 CLAYEY SAND (SC) - brown to light brown SANDSTONE - gray, with shale layers Boring Terminated at 30 feet. 29 27 36 37 CFA B- 7 RE C % 5 10 15 20 25 30 Surface Elevation Sy m b o l 1-10-15 Sa m p l e s Water Observations (feet) Completion Date LOG OF BORING NO. Pl a s t i c Li m i t , % Completion Depth Project No. 14-19770 Proposed Prologis Park One Twenty One - Subaru BTS Warehouse Coppell, Texas Pa s s i n g N o . 2 0 0 Si e v e , % Dr y U n i t W e i g h t pc f Pl a s t i c i t y In d e x Li q u i d Li m i t , % Pe n e t r o m e t e r Re a d i n g , T S F SP T - B l o w s / F o o t TC P - B l o w s / I n c h 478.0 De p t h , F t . Plate A.10 Location B- 7 Boring No. Un c o n f i n e d Co m p r e s s i o n ps f Type Stratum Description Mo i s t u r e Co n t e n t , % 30.0' While Drilling 16 24 Not Measured At Boring Completion End of Day After Boring Completion RO N E E N G I N E E R I N G L O G S - 1 1 4 - 1 9 7 7 0 . G P J R O N E . G D T 1 / 2 6 / 1 5 469.5 465.5 457.5 14 15 4.00 4.5+ 4.5+ 4.5+ 4.5+ 4.5+ 100/1.25'' 100/3.75'' 100/2.5'' 14 3 10 8 11 10 12 28 SANDY LEAN CLAY (CL) - brown to dark brown SANDSTONE - tan and gray, with shale layers SHALE - gray Boring Terminated at 30 feet. 61 76 26 43 CFA B- 8 RE C % 5 10 15 20 25 30 Surface Elevation Sy m b o l 1-10-15 Sa m p l e s Water Observations (feet) Completion Date LOG OF BORING NO. Pl a s t i c Li m i t , % Completion Depth Project No. 14-19770 Proposed Prologis Park One Twenty One - Subaru BTS Warehouse Coppell, Texas Pa s s i n g N o . 2 0 0 Si e v e , % Dr y U n i t W e i g h t pc f Pl a s t i c i t y In d e x Li q u i d Li m i t , % Pe n e t r o m e t e r Re a d i n g , T S F SP T - B l o w s / F o o t TC P - B l o w s / I n c h 487.5 De p t h , F t . Plate A.11 Location B- 8 Boring No. Un c o n f i n e d Co m p r e s s i o n ps f Type Stratum Description Mo i s t u r e Co n t e n t , % 30.0' While Drilling Not Encountered Not Encountered Not Measured At Boring Completion End of Day After Boring Completion RO N E E N G I N E E R I N G L O G S - 1 1 4 - 1 9 7 7 0 . G P J R O N E . G D T 1 / 2 6 / 1 5 468.0 462.0 450.0 15 2.25 4.5+ 4.5+ 3.50 2.50 100/1.25'' 100/5.75'' 100/5.5'' 100/5.5'' 16 13 13 15 18 13 8 14 16 17 26 LEAN CLAY (CL) - brown to light brown with sandstone fragments SANDSTONE - gray, with shale layers SHALE - gray, with sandstone seams Boring Terminated at 30 feet. 86 41 CFA B- 9 RE C % 5 10 15 20 25 30 Surface Elevation Sy m b o l 1-12-15 Sa m p l e s Water Observations (feet) Completion Date LOG OF BORING NO. Pl a s t i c Li m i t , % Completion Depth Project No. 14-19770 Proposed Prologis Park One Twenty One - Subaru BTS Warehouse Coppell, Texas Pa s s i n g N o . 2 0 0 Si e v e , % Dr y U n i t W e i g h t pc f Pl a s t i c i t y In d e x Li q u i d Li m i t , % Pe n e t r o m e t e r Re a d i n g , T S F SP T - B l o w s / F o o t TC P - B l o w s / I n c h 480.0 De p t h , F t . Plate A.12 Location B- 9 Boring No. Un c o n f i n e d Co m p r e s s i o n ps f Type Stratum Description Mo i s t u r e Co n t e n t , % 30.0' While Drilling 25.5 28 Not Measured At Boring Completion End of Day After Boring Completion RO N E E N G I N E E R I N G L O G S - 1 1 4 - 1 9 7 7 0 . G P J R O N E . G D T 1 / 2 6 / 1 5 470.5 466.5 450.5 448.5 12 17 2.50 2.50 4.5+ 2.50 4.5+ 100/0.75'' 100/1.5'' 100/1.75'' 100/6'' 12 9 6 10 18 7 10 13 17 8 21 CLAYEY SAND (SC) - brown to light brown LEAN CLAY (CL) - gray SANDSTONE - gray, with shale layers SHALE - gray, with sandstone seams Boring Terminated at 30 feet. 47 99 20 38 CFA B-10 RE C % 5 10 15 20 25 30 Surface Elevation Sy m b o l 1-12-15 Sa m p l e s Water Observations (feet) Completion Date LOG OF BORING NO. Pl a s t i c Li m i t , % Completion Depth Project No. 14-19770 Proposed Prologis Park One Twenty One - Subaru BTS Warehouse Coppell, Texas Pa s s i n g N o . 2 0 0 Si e v e , % Dr y U n i t W e i g h t pc f Pl a s t i c i t y In d e x Li q u i d Li m i t , % Pe n e t r o m e t e r Re a d i n g , T S F SP T - B l o w s / F o o t TC P - B l o w s / I n c h 478.5 De p t h , F t . Plate A.13 Location B-10 Boring No. Un c o n f i n e d Co m p r e s s i o n ps f Type Stratum Description Mo i s t u r e Co n t e n t , % 30.0' While Drilling Not Encountered Not Encountered Not Measured At Boring Completion End of Day After Boring Completion RO N E E N G I N E E R I N G L O G S - 1 1 4 - 1 9 7 7 0 . G P J R O N E . G D T 1 / 2 6 / 1 5 476.0 469.5 463.0 458.0 15 14 4.00 4.5+ 4.5+ 4.5+ 4.5+ N=38 N=50/5" 100/4.25'' 100/3.5'' 19 12 12 11 10 7 11 28 23 LEAN CLAY (CL) - brown to dark brown SILTY SAND (SM) - light brown SANDSTONE - gray, with shale layers SHALE - gray Boring Terminated at 30 feet. 91 81 43 37 CFA B-11 RE C % 5 10 15 20 25 30 Surface Elevation Sy m b o l 1-10-15 Sa m p l e s Water Observations (feet) Completion Date LOG OF BORING NO. Pl a s t i c Li m i t , % Completion Depth Project No. 14-19770 Proposed Prologis Park One Twenty One - Subaru BTS Warehouse Coppell, Texas Pa s s i n g N o . 2 0 0 Si e v e , % Dr y U n i t W e i g h t pc f Pl a s t i c i t y In d e x Li q u i d Li m i t , % Pe n e t r o m e t e r Re a d i n g , T S F SP T - B l o w s / F o o t TC P - B l o w s / I n c h 488.0 De p t h , F t . Plate A.14 Location B-11 Boring No. Un c o n f i n e d Co m p r e s s i o n ps f Type Stratum Description Mo i s t u r e Co n t e n t , % 30.0' While Drilling Not Encountered Not Encountered Not Measured At Boring Completion End of Day After Boring Completion RO N E E N G I N E E R I N G L O G S - 1 1 4 - 1 9 7 7 0 . G P J R O N E . G D T 1 / 2 6 / 1 5 476.0 470.0 454.0 452.0 13 17 1.50 4.5+ 3.50 1.75 0.50 4.5+ 100/0.75'' N=50/5" N=50/6" 20 8 12 16 23 10 13 16 17 18 34 SANDY LEAN CLAY (CL) - brown to dark brown SANDY FAT CLAY (CH) - gray SANDSTONE - gray, with shale layers SHALEY CLAY (CH) - gray, with sandstone fragments Boring Terminated at 30 feet. 60 51 31 51 CFA B-12 RE C % 5 10 15 20 25 30 Surface Elevation Sy m b o l 1-8-15 Sa m p l e s Water Observations (feet) Completion Date LOG OF BORING NO. Pl a s t i c Li m i t , % Completion Depth Project No. 14-19770 Proposed Prologis Park One Twenty One - Subaru BTS Warehouse Coppell, Texas Pa s s i n g N o . 2 0 0 Si e v e , % Dr y U n i t W e i g h t pc f Pl a s t i c i t y In d e x Li q u i d Li m i t , % Pe n e t r o m e t e r Re a d i n g , T S F SP T - B l o w s / F o o t TC P - B l o w s / I n c h 482.0 De p t h , F t . Plate A.15 Location B-12 Boring No. Un c o n f i n e d Co m p r e s s i o n ps f Type Stratum Description Mo i s t u r e Co n t e n t , % 30.0' While Drilling 23 30 Not Measured At Boring Completion End of Day After Boring Completion RO N E E N G I N E E R I N G L O G S - 1 1 4 - 1 9 7 7 0 . G P J R O N E . G D T 1 / 2 6 / 1 5 475.5 467.5 451.5 449.5 13 14 2.25 2.25 4.5+ 4.5+ 4.5+ N=50/2.5" 100/1.5'' N=50/6" 100/4.5'' 12 9 13 11 18 13 17 18 11 20 CLAYEY SAND (SC) - brown to light brown SANDY LEAN CLAY (CL) - light brow and gray SANDSTONE - gray, with shale layers SHALE - gray, with sandstone seams Boring Terminated at 30 feet. 44 56 24 34 CFA B-13 RE C % 5 10 15 20 25 30 Surface Elevation Sy m b o l 1-12-15 Sa m p l e s Water Observations (feet) Completion Date LOG OF BORING NO. Pl a s t i c Li m i t , % Completion Depth Project No. 14-19770 Proposed Prologis Park One Twenty One - Subaru BTS Warehouse Coppell, Texas Pa s s i n g N o . 2 0 0 Si e v e , % Dr y U n i t W e i g h t pc f Pl a s t i c i t y In d e x Li q u i d Li m i t , % Pe n e t r o m e t e r Re a d i n g , T S F SP T - B l o w s / F o o t TC P - B l o w s / I n c h 479.5 De p t h , F t . Plate A.16 Location B-13 Boring No. Un c o n f i n e d Co m p r e s s i o n ps f Type Stratum Description Mo i s t u r e Co n t e n t , % 30.0' While Drilling Not Encountered Not Encountered Not Measured At Boring Completion End of Day After Boring Completion RO N E E N G I N E E R I N G L O G S - 1 1 4 - 1 9 7 7 0 . G P J R O N E . G D T 1 / 2 6 / 1 5 472.5 469.5 460.5 449.5 13 NP 4.5+ 4.5+ 4.5+ 4.5+ N=9 N=32 100/3.25'' 100/3.25'' 100/2.25'' 12 8 8 7 4 17 14 17 9 17 NP LEAN CLAY (CL) - brown to dark brown SILTY SAND (SM) - light brown SHALEY CLAY (CH) - gray, with sandstone seams SHALE - gray with sandstone seams Boring Terminated at 30 feet. 88 10 30 NP CFA B-14 RE C % 5 10 15 20 25 30 Surface Elevation Sy m b o l 1-13-15 Sa m p l e s Water Observations (feet) Completion Date LOG OF BORING NO. Pl a s t i c Li m i t , % Completion Depth Project No. 14-19770 Proposed Prologis Park One Twenty One - Subaru BTS Warehouse Coppell, Texas Pa s s i n g N o . 2 0 0 Si e v e , % Dr y U n i t W e i g h t pc f Pl a s t i c i t y In d e x Li q u i d Li m i t , % Pe n e t r o m e t e r Re a d i n g , T S F SP T - B l o w s / F o o t TC P - B l o w s / I n c h 479.5 De p t h , F t . Plate A.17 Location B-14 Boring No. Un c o n f i n e d Co m p r e s s i o n ps f Type Stratum Description Mo i s t u r e Co n t e n t , % 30.0' While Drilling Not Encountered Not Encountered Not Measured At Boring Completion End of Day After Boring Completion RO N E E N G I N E E R I N G L O G S - 1 1 4 - 1 9 7 7 0 . G P J R O N E . G D T 1 / 2 6 / 1 5 462.0 448.0 13 13 4.5+ 4.50 2.50 1.25 4.5+ 2.25 100/4.25'' 100/3.25'' 100/3.5'' 11 13 16 13 16 22 17 LEAN CLAY (CL) - brown to light brown, with trace gravel SHALE - gray Boring Terminated at 30 feet. 73 79 35 30 CFA B-15 RE C % 5 10 15 20 25 30 Surface Elevation Sy m b o l 1-14-15 Sa m p l e s Water Observations (feet) Completion Date LOG OF BORING NO. Pl a s t i c Li m i t , % Completion Depth Project No. 14-19770 Proposed Prologis Park One Twenty One - Subaru BTS Warehouse Coppell, Texas Pa s s i n g N o . 2 0 0 Si e v e , % Dr y U n i t W e i g h t pc f Pl a s t i c i t y In d e x Li q u i d Li m i t , % Pe n e t r o m e t e r Re a d i n g , T S F SP T - B l o w s / F o o t TC P - B l o w s / I n c h 478.0 De p t h , F t . Plate A.18 Location B-15 Boring No. Un c o n f i n e d Co m p r e s s i o n ps f Type Stratum Description Mo i s t u r e Co n t e n t , % 30.0' While Drilling Not Encountered Not Encountered Not Measured At Boring Completion End of Day After Boring Completion RO N E E N G I N E E R I N G L O G S - 1 1 4 - 1 9 7 7 0 . G P J R O N E . G D T 1 / 2 6 / 1 5 498.0 495.0 13 4.25 4.5+ 12 7 8 21 SANDY LEAN CLAY (CL) - brown CLAYEY SAND (SC) - light brown Boring Terminated at 5 feet. 43 34 CFA B-16 RE C % 5 Surface Elevation Sy m b o l 1-12-15 Sa m p l e s Water Observations (feet) Completion Date LOG OF BORING NO. Pl a s t i c Li m i t , % Completion Depth Project No. 14-19770 Proposed Prologis Park One Twenty One - Subaru BTS Warehouse Coppell, Texas Pa s s i n g N o . 2 0 0 Si e v e , % Dr y U n i t W e i g h t pc f Pl a s t i c i t y In d e x Li q u i d Li m i t , % Pe n e t r o m e t e r Re a d i n g , T S F SP T - B l o w s / F o o t TC P - B l o w s / I n c h 500.0 De p t h , F t . Plate A.19 Location B-16 Boring No. Un c o n f i n e d Co m p r e s s i o n ps f Type Stratum Description Mo i s t u r e Co n t e n t , % 5.0' While Drilling Not Encountered Not Encountered Not Measured At Boring Completion End of Day After Boring Completion RO N E E N G I N E E R I N G L O G S - 1 1 4 - 1 9 7 7 0 . G P J R O N E . G D T 1 / 2 6 / 1 5 496.0 493.0 13 3.75 N=8 N=20 11 9 31 LEAN CLAY (CL) - brown SILTY SAND (SM) - brown Boring Terminated at 5 feet. 34 14 CFA B-17 RE C % 5 Surface Elevation Sy m b o l 1-12-15 Sa m p l e s Water Observations (feet) Completion Date LOG OF BORING NO. Pl a s t i c Li m i t , % Completion Depth Project No. 14-19770 Proposed Prologis Park One Twenty One - Subaru BTS Warehouse Coppell, Texas Pa s s i n g N o . 2 0 0 Si e v e , % Dr y U n i t W e i g h t pc f Pl a s t i c i t y In d e x Li q u i d Li m i t , % Pe n e t r o m e t e r Re a d i n g , T S F SP T - B l o w s / F o o t TC P - B l o w s / I n c h 498.0 De p t h , F t . Plate A.20 Location B-17 Boring No. Un c o n f i n e d Co m p r e s s i o n ps f Type Stratum Description Mo i s t u r e Co n t e n t , % 5.0' While Drilling Not Encountered Not Encountered Not Measured At Boring Completion End of Day After Boring Completion RO N E E N G I N E E R I N G L O G S - 1 1 4 - 1 9 7 7 0 . G P J R O N E . G D T 1 / 2 6 / 1 5 491.5 154.5+ 4.5+ 4.5+ 4.5+ 13 9 10 10 30LEAN CLAY (CL) - brown to light brown Boring Terminated at 5 feet. 84 45 CFA B-18 RE C % 5 Surface Elevation Sy m b o l 1-8-15 Sa m p l e s Water Observations (feet) Completion Date LOG OF BORING NO. Pl a s t i c Li m i t , % Completion Depth Project No. 14-19770 Proposed Prologis Park One Twenty One - Subaru BTS Warehouse Coppell, Texas Pa s s i n g N o . 2 0 0 Si e v e , % Dr y U n i t W e i g h t pc f Pl a s t i c i t y In d e x Li q u i d Li m i t , % Pe n e t r o m e t e r Re a d i n g , T S F SP T - B l o w s / F o o t TC P - B l o w s / I n c h 496.5 De p t h , F t . Plate A.21 Location B-18 Boring No. Un c o n f i n e d Co m p r e s s i o n ps f Type Stratum Description Mo i s t u r e Co n t e n t , % 5.0' While Drilling Not Encountered Not Encountered Not Measured At Boring Completion End of Day After Boring Completion RO N E E N G I N E E R I N G L O G S - 1 1 4 - 1 9 7 7 0 . G P J R O N E . G D T 1 / 2 6 / 1 5 496.5 13 4.00 4.5+ 4.5+ 12 10 9 25 LEAN CLAY (CL) - brown, with calcareous nodules Boring Terminated at 5 feet. 81 38 CFA B-19 RE C % 5 Surface Elevation Sy m b o l 1-8-15 Sa m p l e s Water Observations (feet) Completion Date LOG OF BORING NO. Pl a s t i c Li m i t , % Completion Depth Project No. 14-19770 Proposed Prologis Park One Twenty One - Subaru BTS Warehouse Coppell, Texas Pa s s i n g N o . 2 0 0 Si e v e , % Dr y U n i t W e i g h t pc f Pl a s t i c i t y In d e x Li q u i d Li m i t , % Pe n e t r o m e t e r Re a d i n g , T S F SP T - B l o w s / F o o t TC P - B l o w s / I n c h 501.5 De p t h , F t . Plate A.22 Location B-19 Boring No. Un c o n f i n e d Co m p r e s s i o n ps f Type Stratum Description Mo i s t u r e Co n t e n t , % 5.0' While Drilling Not Encountered Not Encountered Not Measured At Boring Completion End of Day After Boring Completion RO N E E N G I N E E R I N G L O G S - 1 1 4 - 1 9 7 7 0 . G P J R O N E . G D T 1 / 2 6 / 1 5 495.5 14 2.25 3.50 4.5+ 4.5+ 12 13 8 1128 LEAN CLAY (CL) - brown to light brown, with sand and calcareous nodules Boring Terminated at 5 feet. 73 42 CFA B-20 RE C % 5 Surface Elevation Sy m b o l 1-8-15 Sa m p l e s Water Observations (feet) Completion Date LOG OF BORING NO. Pl a s t i c Li m i t , % Completion Depth Project No. 14-19770 Proposed Prologis Park One Twenty One - Subaru BTS Warehouse Coppell, Texas Pa s s i n g N o . 2 0 0 Si e v e , % Dr y U n i t W e i g h t pc f Pl a s t i c i t y In d e x Li q u i d Li m i t , % Pe n e t r o m e t e r Re a d i n g , T S F SP T - B l o w s / F o o t TC P - B l o w s / I n c h 500.5 De p t h , F t . Plate A.23 Location B-20 Boring No. Un c o n f i n e d Co m p r e s s i o n ps f Type Stratum Description Mo i s t u r e Co n t e n t , % 5.0' While Drilling Not Encountered Not Encountered Not Measured At Boring Completion End of Day After Boring Completion RO N E E N G I N E E R I N G L O G S - 1 1 4 - 1 9 7 7 0 . G P J R O N E . G D T 1 / 2 6 / 1 5 494.5 16 3.75 4.5+ 4.5+ 17 11 10 32 LEAN CLAY (CL) - brown to light brown, with calcareous nodules Boring Terminated at 5 feet. 92 48 CFA B-21 RE C % 5 Surface Elevation Sy m b o l 1-8-15 Sa m p l e s Water Observations (feet) Completion Date LOG OF BORING NO. Pl a s t i c Li m i t , % Completion Depth Project No. 14-19770 Proposed Prologis Park One Twenty One - Subaru BTS Warehouse Coppell, Texas Pa s s i n g N o . 2 0 0 Si e v e , % Dr y U n i t W e i g h t pc f Pl a s t i c i t y In d e x Li q u i d Li m i t , % Pe n e t r o m e t e r Re a d i n g , T S F SP T - B l o w s / F o o t TC P - B l o w s / I n c h 499.5 De p t h , F t . Plate A.24 Location B-21 Boring No. Un c o n f i n e d Co m p r e s s i o n ps f Type Stratum Description Mo i s t u r e Co n t e n t , % 5.0' While Drilling Not Encountered Not Encountered Not Measured At Boring Completion End of Day After Boring Completion RO N E E N G I N E E R I N G L O G S - 1 1 4 - 1 9 7 7 0 . G P J R O N E . G D T 1 / 2 6 / 1 5 500.5 498.5 15 1.50 3.00 N=15 16 10 57 SANDY LEAN CLAY (CL) - brown to light brown SILTY CLAYEY SAND (SC-SM) - light brown Boring Terminated at 5 feet. 30 22 CFA B-22 RE C % 5 Surface Elevation Sy m b o l 1-8-15 Sa m p l e s Water Observations (feet) Completion Date LOG OF BORING NO. Pl a s t i c Li m i t , % Completion Depth Project No. 14-19770 Proposed Prologis Park One Twenty One - Subaru BTS Warehouse Coppell, Texas Pa s s i n g N o . 2 0 0 Si e v e , % Dr y U n i t W e i g h t pc f Pl a s t i c i t y In d e x Li q u i d Li m i t , % Pe n e t r o m e t e r Re a d i n g , T S F SP T - B l o w s / F o o t TC P - B l o w s / I n c h 503.5 De p t h , F t . Plate A.25 Location B-22 Boring No. Un c o n f i n e d Co m p r e s s i o n ps f Type Stratum Description Mo i s t u r e Co n t e n t , % 5.0' While Drilling Not Encountered Not Encountered Not Measured At Boring Completion End of Day After Boring Completion RO N E E N G I N E E R I N G L O G S - 1 1 4 - 1 9 7 7 0 . G P J R O N E . G D T 1 / 2 6 / 1 5 503.5 500.5 13 13 N=32 N=16 14 9 7 21 16 CLAYEY SAND (SC) - brown to light brown SANDY LEAN CLAY (CL) - light brown Boring Terminated at 5 feet. 49 51 34 29 CFA B-23 RE C % 5 Surface Elevation Sy m b o l 1-14-15 Sa m p l e s Water Observations (feet) Completion Date LOG OF BORING NO. Pl a s t i c Li m i t , % Completion Depth Project No. 14-19770 Proposed Prologis Park One Twenty One - Subaru BTS Warehouse Coppell, Texas Pa s s i n g N o . 2 0 0 Si e v e , % Dr y U n i t W e i g h t pc f Pl a s t i c i t y In d e x Li q u i d Li m i t , % Pe n e t r o m e t e r Re a d i n g , T S F SP T - B l o w s / F o o t TC P - B l o w s / I n c h 505.5 De p t h , F t . Plate A.26 Location B-23 Boring No. Un c o n f i n e d Co m p r e s s i o n ps f Type Stratum Description Mo i s t u r e Co n t e n t , % 5.0' While Drilling Not Encountered Not Encountered Not Measured At Boring Completion End of Day After Boring Completion RO N E E N G I N E E R I N G L O G S - 1 1 4 - 1 9 7 7 0 . G P J R O N E . G D T 1 / 2 6 / 1 5 Plate A.29 SWELL TEST RESULTS GEOTECHNICAL ENGINEERING REPORT Proposed Prologis Park Coppell, Texas Rone Project No. 14-18896 Boring Depth (ft) Liquid Limit Plastic Limit Plasticity Index Initial MC (%) Final MC (%) Load (psf) Swell (%) B- 1 2-4 52 17 35 19 20 375 1.4 B- 2 4-6 23 17 6 20 19 625 0.0 B- 3 4-6 42 14 28 10 14 625 4.0 B- 4 2-4 37 14 23 13 14 375 0.5 B- 4 8-10 19 17 2 22 18 1125 0.0 Boring Depth (ft) Liquid Limit Plastic Limit Plasticity Index Initial MC (%) Final MC (%) Load (psf) Swell (%) B- 5 0-2 28 14 14 16 16 125 0.0 B- 6 2-4 34 14 20 9 14 375 5.7 B- 6 6-8 36 14 22 13 16 875 2.0 B- 7 0-2 36 15 21 14 14 125 0.0 B- 8 2-4 26 14 12 11 19 375 0.0 B- 9 4-6 41 15 26 14 19 625 1.8 B-10 8-10 38 17 21 18 19 1125 0.2 B-11 6-8 37 14 23 11 16 875 4.2 B-12 6-8 51 17 34 15 15 875 0.1 B-13 6-8 34 14 20 10 13 875 0.0 B-14 2-4 30 13 17 8 15 375 2.3 B-15 2-4 35 13 22 11 13 375 0.8 B-15 6-8 30 13 17 16 16 875 0.0 Rone Project Number: 14-19770 Coppell, Texas Proposed Prologis Park One Twenty One - Subaru BTS Warehouse Geotechnical Engineering Report SWELL TEST RESULTS Plate A.30 APPENDIX B B-1 FIELD OPERATIONS Subsurface conditions were defined by a total of 23 borings located as shown on the Boring Location Diagram, Plate A.3. The borings were drilled at locations staked in the field by Rone. The borings were advanced between sample intervals using continuous flight auger drilling procedures. The results of the borings are shown graphically on the Log s of Boring, Plates A.4 through A.26. Sample depth, description, and soil classification based on the Unified Soil Classification System are shown on the Logs of Boring. Keys to the symbols and terms used on the Logs of Boring are presented on Plates A.27 and A.28. Relatively undisturbed samples of cohesive soils were obtained with Shelby tube samplers in general accordance with ASTM D1587 at the locations shown on the Log of Boring. The Shelby tube sampler consists of a thin-walled steel tube with a sharp cutting edge connected to a head equipped with a ball valve threaded for rod connection. The tube is pushed into the undisturbed soils by the hydraulic pull- down of the drilling rig. The soil specimens were extruded from the tube in the field, logged, tested for consistency with a hand penetrometer, sealed, and packaged to maintain "in situ" moisture content. The consistency of cohesive soil samples was evaluated in the field using a calibrated hand penetrometer. In this test, a 0.25-inch diameter piston is pushed into the undisturbed sample at a constant rate to a depth of 0.25 -inch. The results of these tests are tabulated at respective sample depths on the logs. When the capacity of the penetrometer is exceeded, the value is tabulated as 4.5+. Samples of granular materials were also obtained using split-barrel sampling procedures in general accordance with ASTM D1586. In the split-barrel procedure, a disturbed sample is obtained in a standard 2 inch OD split barrel-sampling spoon driven into 18 inches into the ground using a 140 - pound hammer falling freely 30 inches. The number of blows for the last 12 inches of a standard 18-inch penetration is recorded as the Standard Penetration Test resistance (N -value). The N- values are recorded on the boring logs at the depth of sampling. The samples were sealed and returned to our laboratory for further examination and testing. The shale and sandstone encountered was also evaluated with a modified version of the Texas Cone Penetration test. Texas Department of Transportation (TX-DOT) Test Method Tex-132-E specifies driving a 3-inch diameter cone with a 170-pound hammer freely falling 24 inches. This results in 340 B-1 foot-pounds of energy for each blow. This method was modified by utilizing a 140-pound hammer freely falling 30 inches. This results in 350 foot-pounds of energy for each hammer blow. In relatively soft materials, the penetrometer cone is driven 1 foot and the number of blows required for each 6-inch penetration is tabulated at respected test depths, as blows per 6 inches on the log. In hard materials (rock or rock-like), the penetrometer cone is driven with the resulting penetrations, in inches, recorded for the first and second 50 blows, a total of 100 blows. The penetration for the total 100 blows is recorded at the respective testing depths on the boring logs. Groundwater observations during and after completion of the boring are shown on the upper right of the boring log. Upon completion of the boring, the borehole was backfilled from the top and plugged at the surface. B-2 LABORATORY TESTING General Laboratory tests were performed to define pertinent engineering characteristics of the soils encountered. The laboratory tests included moisture content, gradation (percentage of material passing through a standard U.S. No. 200 sieve), Atterberg limits, and visual classification. Classification Tests Classification of soils was verified by natural moisture content and Atterberg limits determinations. These tests were performed in general accordance with American Society for Testing and Materials (ASTM) procedures. The Atterberg limits, gradations and natural moisture content determinations are presented at the respective sample depths on the Log of Boring. Free Swell Tests Selected samples of the near-surface cohesive soils were subjected to free swell tests. In the free swell test, a sample is placed in a consolidometer and subjected to the estimated overburden pressure. The sample is then inundated with water and allowed to swell. Moisture contents are determined both before and after completion of the test. Test results are recorded as the percent swell, with initial and final moisture content.