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Duke Lesley 2RC-CS121227 s' ,OV‘x- %,¢tel Q I')u� C 64- -(% `4*:: GEOTECHNICAL INVESTIGATION COPPELL CONVENTION HOTEL COPPELL, TEXAS ,lam 4F ;-,,.4.v* """ : , AGG REPORT NO. E12-1106 V. / 5, ,,, DECEMBER 27, 2012 ir 4 \p„,:„..„ . ,,\,:,..„,,,,, .., :„,,,., . . ,.,,.„,4 III j ,f X19 III 1 PREPARED FOR: .t ° so ONE GROUP DESIGN, L.P. • 1 PRESENTED 8Y: _ ` FILL IAI'ICE 'a ` (IGO GEOTEO111ICAL 1 , ' GROUP z. . ^^--r Geotechnical Engineering-Environmental Consulting-Construction Materials Engineering Testing 3228 Halifax Street - Dallas,TX 75247 Ph, 972.444.8889 FX.972.444.8893 ICE TECHNIL • GEOTECHNICAL ENGINEERING GROUP • ENVIRONMENTAL CONSULTING • CONSTRUCTION MATERIALS ENGINEERING AND TESTING December 27, 2012 Mr. Gary Murphree, AIA One Group Design, L.P. 2311 Texas Drive, Suite 105 Irving, Texas 75062 Phone: (972) 255-9464 Email: gary@savaone.com Re: Geotechnical Investigation Coppell Convention Hotel Coppell, Texas AGG Report No. E12-1106 Dear Mr. Murphree: Please find enclosed our report summarizing the results of the geotechnical investigation performed at the above referenced project site. We trust the recommendations derived from this investigation will provide you with the information necessary to complete your proposed project successfully. For your future construction materials testing and related quality control requirements, it is recommended that the work be performed by Alliance Geotechnical Group, Inc. in order to maintain continuity of inspection and testing services for the project under the direction of the geotechnical project engineer. We thank you for the opportunity to provide you with our professional services. If we can be of further assistance, please do not hesitate to contact us. Sincerely, ALLIANCE GEOTECHNICAL GROUP, INC. ,c,OTECHN `f��''SOF T}�•�����■/��� {. �^.� �.•••N1.•�:..� V� .'mow,,,,/ ichael D. R. .nd, P.E. q`ys;_' � , /Go Mark J. Farrow, P.E. Principal S Senior Vice President /MICHAEL DANE ROLAND� 96043 :' ,� 0%ticEt40-4`,0 197 MEMBER 3228 Halifax Street • Dallas, Texas 75247 ,,���� AC IL Tel:972-444-8889 • Fax: 972-444-8893 • www.aggengr.com �'��''Z TABLE OF CONTENTS PAGE 1.0 PROJECT INFORMATION 1 2.0 SCOPE OF INVESTIGATION 1 3.0 FIELD OPERATIONS 1 4.0 LABORATORY TESTING 2 5.0 SURFACE CONDITIONS 3 5.1 GENERAL SITE CONDITIONS 3 5.2 SUBSURFACE CONDITIONS 3 5.3 SUBSURFACE CONDITIONS 3 5.4 GROUNDWATER 3 5.5 SOIL MOVEMENT 3 6.0 EXECUTIVE SUMMARY 4 7.0 PIER FOUNDATION RECOMMENDATIONS (OPTIONS 1 & 2) 5 7.1 STRAIGHT SHAFT FOUNDATION SYSTEM (OPTION 1) 5 7.2 DRILLED SHAFT SOIL INDUCED UPLIFT LOADS 6 7.3 DRILLED SHAFT CONSTRUCTION CONSIDERATIONS 7 7.4 GRADE BEAMS 8 7.5 FLOOR SLAB 8 7.6 FLAT WORK AND PIPING CONSIDERATIONS 9 7.7 BELLED PIER FOUNDATION SYSTEM (OPTION 2) 9 8.0 PTI FOUNDATION RECOMMENDATIONS (OPTIONS 3 & 4) 10 8.1 BUILDING PAD WORK - OPTION 3 (PVR OF 1 INCH) 10 8.2 BUILDING PAD WORK - OPTION 4 (PVR OF 3 INCHES) 11 8.3 POST-TENSIONING PARAMETERS (2005 PTI THIRD EDITION) -- 12 8.3.1 FOUNDATION DESIGN RECOMMENDATIONS 13 9.0 PAVEMENT RECOMMENDATIONS 15 9.1 SUBGRADE PREPARATION 15 9.2 RECOMPACTED PAVEMENT SUBGRADE 15 9.3 DRIVE APPROACHES 16 9.4 PAVEMENT SECTIONS 16 9.5 PAVEMENT CONSIDERATIONS 18 10.0 EARTHWORK GUIDELINES 19 10.1 SITE GRADING AND DRAINAGE 19 10.2 PROOFROLLING AND SUBGRADE PREPARATION 20 10.3 SELECT FILL 20 ALLIANCE GEOTECHNICAL GROUP E12-1106 10.4 ON-SITE CLAY FILL PLACEMENT IN PAVEMENT AND LANDSCAPING AREAS 20 10.5 ON-SITE CLAY FILL PLACEMENT IN BUILDING AREAS 20 10.5.1 MOISTURE CONDITIONING PRIOR TO COMPACTION 20 10.5.2QUALITY ASSURANCE REQUIREMENTS 21 10.6 FIELD SUPERVISION AND DENSITY TESTING 22 11.0 LIMITATIONS 22 FIGURES PLAN OF BORINGS 1 LOGS OF BORING 2 through 10 KEY TO TERMS OF BORINGS 11 SWELL TEST SUMMARY 12 APPENDIX APPENDIX MEASURESURES TO MINIMIZE DEEP SEATED SWELL ALLIANCE GEOTECHNICAL GROUP E12-1106 . • GEOTECHNICAL INVESTIGATION COPELL CONVENTION HOTEL COPPELL, TEXAS 1.0 PROJECT INFORMATION The project consists of a 200 room hotel facility and adjacent conference center. The hotel will consist of two separate, four story, wood frame buildings with plan areas of about 15,000 sf each. The conference center will be a one story structural steel building with a plan area of 16,000 sf. We understand that the preferred foundation systems for the proposed hotel buildings consist of either post-tensioned or conventionally reinforced slab on grade foundations. We further understand that the preferred foundation system for the convention center will consist of either drilled piers or shallow footings. Grading information is not available at this time. For the purpose of this geotechnical investigation, we have assumed that cut and fills to achieve final pad grade will be minimal (less than 2 feet). 2.0 SCOPE OF INVESTIGATION The purposes of the study were to: 1) explore the subsurface conditions at the site, 2) characterize the subsurface conditions by testing the physical and engineering properties of the underlying soil strata and by observing groundwater conditions, 3) provide foundation recommendations for the proposed new structures, 4) provide comments on the presence and effect of expansive clay soils on slab-on-grade construction, 5) provide alternative methods of reducing any anticipated swell movements associated with expansive clay soils, 6) provide pavement subgrade preparation and pavement thickness recommendations, and 7) provided recommendations for site grading and compaction of earthwork. This report was prepared in general accordance with AGG Proposal No. P12-1102E dated November 5, 2012 for the original geotechnical investigation and AGG Proposal No. P12-1209E dated December 14, 2012 for the additional services consisting of extending four of the original test borings to greater depths. 3.0 FIELD OPERATIONS The field investigation consisted of drilling five (5) test borings in the vicinity of the proposed new structures. The test borings were originally drilled to depths of 25 feet below the existing ground surface. Since highly expansive clay soils extended to the full 25 foot boring depths and rock was not encountered, four (4) of the test borings (at the corners) were later ALLIANCE GEOTECHNICAL GROUP El 2-1106 PAGE 1 drilled to greater depths in order to penetrate the unweathered rock. The deeper borings extended to depths ranging from 45 to 55 feet below the existing ground surface. The borings were located at the approximate locations shown on the Plan of Borings (Figure 1). A truck-mounted drilling rig was used to advance these borings and to obtain samples for laboratory evaluation. Undisturbed specimens of the cohesive soils were obtained using standard, thin-walled, seamless tube samplers. These specimens were extruded in the field, logged, sealed, and packaged in plastic sample bags to protect them from disturbance and maintain their in-situ moisture content during transportation to our laboratory. The rock formations were evaluated by the Texas Department of Transportation Penetrometer (TxDOT Cone) test. The TxDOT Cone is driven with the resulting penetration in inches recorded for 100 blows. The results of the TxDOT Cone test are recorded at the respective testing depth on the Logs of Borings. The results of the boring program are presented on the Logs of Borings, Figures 2 thru 10. A key to the descriptive terms and symbols used on the logs is presented on Figure 11. 4.0 LABORATORY TESTING Samples were examined at our laboratory by the project geotechnical engineer. Selected samples were subjected to laboratory tests under the supervision of this engineer. The in-situ unit weight, moisture content, and liquid and plastic limits of selected soil samples were measured. These tests were used to estimate the potential volumetric change of the different soil strata and as an indication of the uniformity of the material. Hand penetrometer tests were performed to provide an indication of the variation of soil strength and soil swell with depth. Unconfined compressive strength testing was performed on selected clay samples to determine the bearing strength at depth. The results from these tests are presented on the Logs of Borings (Figures 2 thru 10). To provide additional information about the swell characteristics of these soils (at their in-situ moisture conditions), absorption swell tests were performed on selected samples of the clay soils (see Figure 12). ALLIANCE GEOTECHNICAL GROUP E12-1106 PAGE 2 5.0 SURFACE CONDITIONS 5.1 GENERAL SITE CONDITIONS The project site is located east of Point West Blvd. about halfway between Dividend Drive and IH 635 in Coppell, Texas. See Plan of Borings (Figure 1) for site configuration, location and aerial view. The site is currently vacant, undeveloped and covered with grass. 5.2 SUBSURFACE CONDITIONS Subsurface conditions encountered in the borings, including descriptions of the various strata and their depths and thicknesses, are presented on the Logs of Boring. Note that depth on all borings refers to the depth from the existing grade or ground surface present at the time of the investigation. Boundaries between the various soil types are approximate. 5.3 SUBSURFACE CONDITIONS As shown on the Dallas sheet of the Geologic Atlas of Texas, the site is located in an area underlain by the Eagle Ford Shale Formation. The Eagle Ford Formation typically consists of interbedded layers of clay, weathered clay shale and shale. Soils derived from this formation are typically highly plastic clays exhibiting a high shrink/swell potential with variations in moisture content. These Eagle Ford shaley clay soils typically have very high soluble sulfate levels. 5.4 GROUNDWATER The borings were advanced with continuous flight auger drilling equipment. This method allows relatively accurate groundwater observations to be made while drilling. Groundwater seepage was encountered within the deeper test borings during drilling at depths ranging from 27 to 29 feet. However, the groundwater encountered within these test borings elevated to depths of 17 to 18 feet by the time of drilling completion of each boring. The subsurface water conditions are subject to change with variations in climatic conditions and are also functions of subsurface soil conditions and rainfall. 5.5 SOIL MOVEMENT The subsurface exploration revealed the presence deep clay and shaley clay soils. The clay soils have a very high shrink/swell potential. Potential Vertical Rise (PVR) calculations were ALLIANCE GEOTECHNICAL GROUP E12-1106 PAGE 3 performed using swell test results, pocket penetrometer readings, and moisture content tests to estimate the swell potential of the soil. Potential Vertical Rise (PVR) values based upon the current dry moisture conditions and current grades have been estimated to exceed 12 inches of anticipated "active zone" swell. In addition, the potential for large additional "deep-seated" swell exists at this site. The assumed "active zone" swell values are upward soil movements that could occur due to typical seasonal moisture changes and soil swelling within the upper ten (10) feet as measured from finished floor grade. The deep-seated swell values are additional upward soil movements that could occur due to moisture changes and soil swelling below a typical ten (10)foot deep "active-zone". Large deep-seated swell (on the order of 6 inches) could occur due to groundwater fluctuations or free water sources such as ponding water conditions, percolation of water in landscaped areas, detention basins, leaking swimming pools, leaking sprinkler lines and/or leaking utility lines that are not detected and repaired in an expedient manner. The potential for large additional deep seated swell exists at this site as indicated on the Swell Test Results (Figure 12) of this report. if the risk of large additional deep-seated swell is not desired, pier foundation systems in conjunction with structural floors should be used. Additional measures to minimize deep seated swell associated with free water sources are provided in the Appendix to this report. 6.0 EXECUTIVE SUMMARY The subsurface exploration revealed the presence of highly active clay soils with the potential for very large soil swell movements. In addition, there is a potential for large deep seated soil swell heave at this site. Based on conversations with the design team, it is understood that different foundation options are to be considered for support of the proposed structures. The foundation options provided in this report are as follows: 1. Recommendations for deep cased straight shaft piers founded within the unweathered rock to support the proposed structures in conjunction with structurally supported floor slabs over void space / crawl space. 2. Recommendations for belled piers to support the proposed structures in conjunction with structurally supported floor slabs over void space /crawl space. 3. Recommendations for PTI slab on grade foundation systems supported on prepared subgrade where the soil swell movements have been reduced to about 1 inch. Anticipated subgrade preparation will consist of deep excavation with deep select fill placement over moisture conditioned on-site soil. ALLIANCE GEOTECHNICAL GROUP E12-1106 PAGE 4 4. Recommendations for PTI slab foundation systems supported on prepared subgrade where the soil swell movements have been reduced to about 3 inches. Anticipated subgrade preparation will consist of deep excavation and moisture conditioning of the on-site clay soils and capping with low PI select fill. 7.0 PIER FOUNDATION RECOMMENDATIONS (OPTIONS 1 & 2) 7.1 STRAIGHT SHAFT FOUNDATION SYSTEM (OPTION 1) The proposed structures may be supported by deep drilled straight shaft piers. The drilled shafts should be straight-sided continuously reinforced shafts that bear within the moderately hard to hard unweathered dark gray shale. Due to the presence of groundwater and jointed shaley clay above the unweathered shale, the drilled shafts will likely have to be cased. We recommend that the drilled shafts penetrate the moderately hard to hard unweathered dark gray shale to the minimum depths indicated in Table 1 to develop the allowable end bearing pressure and provide anchorage resisting uplift forces generated by the expansive clay soils. Unweathered dark gray shale was first encountered within the deeper test borings at depths ranging from 35 to 44 feet below the existing ground surface. It should be noted that actual pier depths required during construction will vary depending upon depth to bearing stratum, depth of cut and/or fill required in the building pad, and design penetrations into the bearing stratum. The allowable end bearing pressure and side resistance pressures are provided in Table 1 and have been developed based on the assumption that a minimum 2 pier diameter clear spacing will be provided between piers. Closer spacing will require some reductions in skin friction. For piers touching, a 50% reduction in skin friction should be used. Where the clear spacing is 3D, no reduction is necessary. For a spacing between 0 and 3D, a straight line interpolation should be used. The skin friction values provided are for compression loading and for resistance to soil swell uplift. For other structural tension loads (sustained uplift or transient uplift due to wind loads), the allowable skin friction is 50% of the value indicated above. These straight shaft foundations should be subject to settlements of less than one-half inch. Differential settlements should be limited to about one-quarter inch. ALLIANCE GEOTECHNICAL GROUP E12-1106 PAGE 5 • TABLE 1. ALLOWABLE BEARING VALUES BEARING STRATA SHAFT LOADING TYPE MODERATELY HARD TO HARD UNWEATHERED DARK GRAY SHALE Axial End Bearing 30,000 psf** Skin Friction Side Resistance 5,000 psf* *For penetrations into moderately hard to hard unweathered dark gray shale exceeding 2 feet or 1D, whichever is larger (where D is pier diameter) as verified by the AGG geotechnical team. The skin friction values provided are for compression loading and for resistance to soil swell uplift. For other structural tension loads (sustained uplift or transient uplift due to wind), the allowable skin friction is 50% of the value indicated above. **A minimum 10 foot penetration into moderately hard to hard unweathered dark gray shale is recommended to develop the allowable end bearing pressure and to resist soil swell uplift. Note: Penetrations into dark gray weathered shale (identified by iron staining or tan colored seams) should not be counted on for the design penetrations during pier installations. The design penetrations should be counted on only for penetrations into continuous moderately hard to hard unweathered dark gray shale as verified by AGG. The design shaft penetrations should be counted on from the bottom of the temporary casing. Shaft penetrations should not be counted on within that portion of the bearing stratum through which the casing is set. 7.2 DRILLED SHAFT SOIL INDUCED UPLIFT LOADS All piers will be subject to uplift loads as a result of swelling within the overlying clays. Straight shafts should be socketed into moderately hard dark gray shale as indicated in Section 7.1 to provide anchorage in resisting uplift forces generated by soil swelling. The piers should have sufficient continuous vertical reinforcing steel extending to the bottom of the piers to resist the computed net uplift loads (uplift less dead load). The magnitude of the uplift loads varies with the shaft diameter, soil parameters, free water sources, and the depth of the active clays acting on the shaft. The uplift pressures can be ALLIANCE GEOTECHNICAL GROUP El 2-1106 PAGE 6 • approximated at this site by assuming a uniform uplift pressure of 2,500 pounds per square foot acting on the shaft perimeter for a depth of 20 feet. 7.3 DRILLED SHAFT CONSTRUCTION CONSIDERATIONS Groundwater was encountered within the jointed shaley clay above the unweathered dark gray shale. Therefore temporary casing will likely be required for the straight shaft pier installations to seal out groundwater and the caving jointed shaley clay prior to and during concrete placement. Temporary casing should be properly seated and sealed in the unweathered shale to prevent seepage and caving into the drilled shaft excavation. Care must then be taken that a sufficient head of plastic concrete is maintained within the casing during extraction. Concrete used for the shafts should have a slump of 6 inches plus or minus 1 inch and placed in a manner to avoid striking the reinforcing steel and walls of the shaft during placement. Complete installation of individual shafts should be accomplished within a 4-hour period in order to help prevent deterioration of bearing surfaces. The drilling of individual shafts should be excavated in a continuous operation and concrete placed as soon as practical after completion of the drilling. No shaft should be left open for more than 8 hours. Eagle Ford shaley clay soils are present at this site and will be in contact with the drilled shafts. The Eagle Ford shaley clay soils typically have very high soluble sulfate levels than can exceed 20,000 ppm. Sulfate levels in excess of 40,000 ppm have been found at some sites. Sulfate resistant concrete mix designs utilizing fly ash are recommended for concrete in contact with these clay soils. The mix design should include the type and amount of cement and the type and amount of fly ash proposed. A locally available fly ash/cement mix design utilizing Type II cement and 25% Type F fly ash or an approved equal is recommended for below grade concrete due to its resistance to sulfate attack. ACI has additional requirements for high sulfate levels (over 20,000 ppm)that should be implemented at this site. We recommend that Alliance Geotechnical Group be retained to observe and document the drilled pier construction. The engineer, or his representative, should document the shaft diameter, pier penetration, casing installations and extractions, depth, cleanliness, plumbness of the shaft, and the type of bearing material. Significant deviations from the specified or anticipated conditions should be reported to the owner's representative and to the structural engineer. The drilled pier excavation should be observed to verify the bottom of the hole is dry and thoroughly cleaned of cuttings after completion and again prior to concrete placement. ALLIANCE GEOTECHNICAL GROUP E12-1106 PAGE 7 7.4 GRADE BEAMS Grade beams supported by piers should be constructed over a void space. A minimum void space of 24 inches should be provided between the bottom of these members and the subgrade. Permanent retainer forms should be used. Structural cardboard forms are one means of providing this void beneath these members. Care must be exercised during concrete placement to avoid collapsing the cardboard void boxes. The cardboard carton forms should not be allowed to become wet or crushed prior to concrete placement. Permanent earth retainer forms should be used. As a quality control measure during construction, "actual" concrete quantities placed should be checked against "anticipated" quantities during construction of the grade beams. Significant concrete "overage"would be an early indication of a collapsed void. The exterior portions of the grade beams along the perimeter of the buildings should be carefully backfilled with on—site clayey soils unless specified otherwise below. The backfill soils should be placed at a moisture content between +1 and +4 percentage points wet of optimum. The fill should be compacted to 95 percent of maximum dry density as determined in accordance with ASTM D-698 (Standard Proctor). Note: "Mushrooming" must not be allowed around top of piers, pier caps or grade beams. 7.5 FLOOR SLAB The subsurface exploration revealed the presence of deep highly expansive shaley clay soils. The clay soils have a very high shrink/swell potential depending upon the soil moisture condition at the time of construction. Potential Vertical Rise (PVR) values based upon the current dry moisture conditions and current grades have been estimated to exceed 12 inches of anticipated "active zone" swell. In addition, the potential for large additional "deep- seated" swell (on the order of 6 inches) exists at this site (see Section 5.5 of this report and see Figure 12). Due to the potential for large slab movements, the floor slabs in conjunction with pier foundation systems at this site should be structurally supported and suspended above the site soils. The structurally supported floor slabs should be suspended above the underlying soils by a crawl space in excess of 24 inches below the bottom of piping hanging from the bottom of the ALLIANCE GEOTECHNICAL GROUP E12-1106 PAGE 8 floor slab. The crawl space should be ventilated and drained. A suitable vapor barrier should be used below all floor slabs. NOTE: A crawl space is recommended to allow utility lines to be hung to the floor system and to allow access for future maintenance. Otherwise, the piping beneath the building would be crushed and fixtures damaged. Appropriate sleeving should be used for piping penetration below or through grade beams to accommodate large differential upward movments as described in this report. 7.6 FLAT WORK AND PIPING CONSIDERATIONS Provisions should be made for large post-construction differential upward movement of adjacent flat work and piping. Site grading plans should include provisions for the effects of soil movements on access and entry slabs and adjacent sidewalks. Utility line details and fixtures should consider the potential for large differential upward movement beneath any piping. See Note in Section 7.5 of this report. To prevent potential tripping hazards, access and entry slabs should be elevated above the adjacent sidewalks and pavement slabs. We recommend that all access and entry slabs also be structurally supported on drilled shafts and suspended above the active clays by a minimum 24 inch drained void space. To prevent potential tripping hazards, these access and entry slabs should be elevated above adjacent sidewalks and pavement slabs and provided with transition slabs over a 24 inch drained void space that are hinged at grade beam connections and provided with toe beams at connections to adjacent flatwork. All void spaces should be drained. These transition slabs should be graded to accommodate large differential upward movements as described in this report. We recommend that Alliance Geotechnical Group be retained to review the project drawings and specifications to ensure compliance with the geotechnical report. If deep excavation and moisture conditioning is performed per Sections 8.1 or 8.2, the potential for large differential upward movements should be considered within 15 to 20 feet of the building. Also, large differential movement of plaza slabs and pavements should be anticipated. AGG should be contacted if it is desired to reduce differential upward movement of plaza slabs and/or pavements. 7.7 BELLED PIER FOUNDATION SYSTEM (OPTION 2) As an alternative to straight shaft pier foundations, belled pier foundations were considered. However, belled pier depths of 25 feet would be required due to the presence of deep highly ALLIANCE GEOTECHNICAL GROUP E12-1106 PAGE 9 • expansive shaley clay. Due to the presence of groundwater at depths of 17 to 18 feet and the presence of jointed shaley clay, caving of the underreams during belling is anticipated. Therefore, belled piers are not recommended at this site. 8.0 PTI FOUNDATION RECOMMENDATIONS (OPTIONS 3 & 4) Based on conversations with the design team, it is understood that PTI slab on grade foundation recommendations to support the proposed structures are also desired. It is further understood that separate PTI slab recommendations are desired to where one design is based upon the PVR being reduced to about one (1) inch and the other design is based upon the PVR being reduced to about three (3) inches. PTI slab recommendations for both of these PVR options are provided in the following sections of this report. 8.1 BUILDING PAD PREPARATION WORK—OPTION 3 (PVR OF 1 INCH) We recommend that the following site preparation work be performed in order to reduce the potential vertical rise to about 1 inch. This assumes that significant deep seated swelling does not occur below depths of 20 feet and that any deep seated swell that does occur is dampened out by the presence of the deep fill over the deeper expansive shaley clay. 1. Excavate to a depth of 20 feet below the existing ground surface or 20 feet below final pad grade, whichever is deeper. Excavations should extend 10 feet beyond building lines or 2 foot beyond adjacent sidewalks and entry areas, whichever is greater. Vertical cuts should not be made. Excavations should be sloped for safety and to minimize differential movement along the sloped transition zones. We recommend that an AGG Engineer review the excavation plan for compliance with this report prior to construction bidding. 2. The upper 10 inches of existing subgrade soil at base of cut should be scarified and compacted as specified in Item #3 below. 3. Fill to within 10 feet of final pad grade using on-site moisture conditioned soils. On- site clay soils can be used as fill within the building pad if the clay soils are moisture conditioned as specified below. Below 10 foot depth: Compact on-site clay soils in maximum 8 inch lifts between +5% to +8% above optimum moisture content to a minimum of 93% Standard Proctor density (ASTM D698). Note: These "targeted" moisture contents are subject to compressive strength verification and 1% average soil swell verifications under the proposed select fill surcharge per Section 10.5.2 of this report. ALLIANCE GEOTECHNICAL GROUP E12-1106 PAGE 10 4. Fill to final pad grade with a minimum of 10 feet of low PI select fill to limits specified in Item 1. The material used as select fill should be a very sandy clay to clayey sand (uniform consistency free of clay clods) with a plasticity index between 7 and 15. The fill should be spread in 8 inch loose lifts and uniformly compacted to a minimum of 97 percent of ASTM Standard D 698 between -2 and +2 percentage points of the soil's optimum moisture content. 5. The upper 40 inches of fill in unpaved areas near the building should consist of compacted on-site clay to minimize water infiltration into the select fill (compact in 8 inch lifts at +1% to +4% above optimum moisture to 95% ASTM D 698). 6. Moisture condition of completed pad must be maintained until all slabs are in place. All work should be performed in accordance with the Earthwork Guidelines (Section 10.0) of this report. 8.2 BUILDING PAD PREPARATION WORK-OPTION 4 (PVR OF 3 INCHES) We recommend that the following site preparation work be performed in order to reduce the potential vertical rise to about 3 inches. This assumes that significant deep seated swelling does not occur below depths of 15 feet and that any deep seated swell that does occur is dampened out by the presence of the deep fill over the deeper expansive shaley clay. 1. Excavate to depth of 15 feet below the existing ground surface or 15 feet below final pad grade, whichever is deeper. Excavations should extend 10 feet beyond building lines or 2 foot beyond adjacent sidewalks and entry areas, whichever is greater. Vertical cuts should not be made. Excavations should be sloped for safety and to minimize differential movement along the sloped transition zones. We recommend that an AGG Engineer review the excavation plan for compliance with this report prior to construction bidding. 2. The upper 10 inches of existing subgrade soil at base of cut should be scarified and compacted as specified in Item #3 below. 3. Fill to within 6 feet of final pad grade using on-site moisture conditioned soils. On-site clay soils can be used as fill within the building pad if the clay soils are moisture conditioned as specified below. 5 to 10 feet below final pad grade: Compact on-site clay soils in maximum 8 inch lifts between +7% to +10% above optimum moisture content to a minimum of 91% Standard Proctor density (ASTM 0698). Below 10 foot depth: Compact on-site clay soils in maximum 8 inch lifts between +5% to +8% above optimum moisture content to a minimum of 93% Standard Proctor density (ASTM D698). ALLIANCE GEOTECHNICAL GROUP E12-1106 PAGE 11 Note: These "targeted" moisture contents are subject to compressive strength verification and 1% average soil swell verifications under the proposed select fill surcharge per Section 10.5.2 of this report. 4. Fill to final pad grade with a minimum of 6 feet of low PI select fill to limits specified in Item 1. The material used as select fill should be a very sandy clay to clayey sand (uniform consistency free of clay clods) with a plasticity index between 7 and 15. The fill should be spread in 8 inch loose lifts and uniformly compacted to a minimum of 97 percent of ASTM Standard D 698 between -2 and +2 percentage points of the soil's optimum moisture content. 5. The upper 40 inches of fill in unpaved areas near the building should consist of compacted on-site clay to minimize water infiltration into the select fill (compact in 8 inch lifts at +1% to +4% above optimum moisture to 95% ASTM D 698). 6. Moisture condition of completed pad must be maintained until all slabs are in place. All work should be performed in accordance with the Earthwork Guidelines (Section 10.0) of this report. 8.3 POST-TENSIONING DESIGN PARAMETERS (2005 PTI THIRD EDITION) Design requirements for post-tensioned slab-on-grade foundations are indicated below for building pads prepared in accordance with either Section 8.1 or Section 8.2 of this report. Design criteria for a slab designed in accordance with the Post-Tensioning Institute's (PTI) slab-on-grade design method have been developed. The edge moisture variation distances (em) for center lift and edge lift conditions were derived based on a Thornthwaite Index ranging from 0 to 20 for the project site. The edge moisture variation distances are based upon the 2005 PTI Manual criteria and are provided in Table 2. PTI differential movement (ym) is indicated in Tables 3 & 4. TABLE 2. RECOMMENDED EDGE MOISTURE VARIATION DISTANCES(em) 2005 PTI Third Edition (Options 3 and 4) Center Lift Condition em = 5.5 feet Edge lift Condition em = 4.5 feet ALLIANCE GEOTECHNICAL GROUP E12-1106 PAGE 12 TABLE 3. RECOMMENDED PTI DIFFERENTIAL MOVEMENTS(ym)* 2005 PTI Third Edition (Option 3) ZONES All Borings Design PVR 1.0 Center Lift Condition ym 3.0 Edge Lift Condition ym 1.0 *The design values indicated above are based on the site preparation work being performed in accordance with Section 8.1 of this report in order to reduce the PVR to about one (1) inch. TABLE 4. RECOMMENDED PTI DIFFERENTIAL MOVEMENTS(y„)** 2005 PTI Third Edition(Option 4) ZONES All Borings Design PVR 3.0 Center Lift Condition ym 4.0 Edge Lift Condition ym 2.0 **The design values indicated above are based on the site preparation work being performed in accordance with Section 8.2 of this report in order to reduce the PVR to about three (3) inches. Note: Required foundation details using the 2005 PTI Third Edition should be evaluated by the structural engineer to verify that beam depths are as deep or deeper and that beam spacings are as close or closer than requirements determined from the previous PTI Second Edition when using the above parameters. If the new design does not result in foundations as stiff or stiffer than the old design, please have your structural engineer consult Alliance Geotechnical Group prior to final design. 8.3.1 FOUNDATION DESIGN RECOMMENDATIONS The Post-Tensioning Institute (PTI) method incorporates numerous design assumptions associated with the derivation of required variables needed to determine the soil design criteria. The PTI method of predicting differential soil movement is applicable only when site moisture conditions are controlled by the climate alone on a well-graded site (i.e. no improper drainage, water leaks or free water sources). Under these conditions, moisture increases ALLIANCE GEOTECHNICAL GROUP E12-1106 PAGE 13 within the supporting soils and the resulting differential foundation movements are much lower than differential movements that can occur due to post-construction movements due to localized saturation caused by free water sources near or beneath the structures. The performance of a slab foundation can be significantly influenced by landscaping details, maintenance, recessed landscaping details, additions near the structures, water line leaks, pool leakage, any other free water sources, as well as by deep rooted trees and shrubs. A polyethylene moisture barrier is recommended below slab-on-grade floor slabs where floor coverings or painted floor surfaces will be applied with products which are sensitive to moisture or if products stored on the building floors are sensitive to moisture. Procedures for installation of vapor barriers are recommended in ACI 302. The slab-on-grade foundation systems may be post-tensioned or conventionally reinforced and should be designed by a structural engineer to withstand the estimated potential soil movements. Grade beams founded in properly compacted low PI select fill soils may be designed using an allowable soil bearing pressure of 2,000 pounds per square foot. We recommend a minimum width of 12 inches for the beams to provide a margin of safety against a local or punching shear failure of the foundation soils. The owners should be advised of the importance of maintaining a moist soil condition within 5 feet of the foundation during prolonged periods of dry weather. Also, the owner should be advised that trees should not be planted within 25 feet of the structure to minimize settlements caused by ground shrinkage associate with moisture absorption of the tree root systems. In order to accommodate differential foundation movements, it is recommended that closely spaced vertical joints be provided along all walls to control cracking associated with differential foundation movement. If swimming pools are to be constructed at this site, specific recommendations for design of all swimming pools, pool decking, and all other flatwork should be provided by Alliance Geotechnical Group to minimize the potential of destructive damage caused by soil movements to the pool and the building foundations. It should be recognized that a post-tensioned or conventionally reinforced slab-on-grade foundation system placed at this site would be subjected to some differential movements as indicated above. These movements can cause cracking of interior sheetrock walls and cracking of exterior brick walls. Differential movements can cause planar movements of widow frames and door frames requiring adjustments to the doors and windows. Cosmetic ALLIANCE GEOTECHNICAL GROUP E12-1106 PAGE 14 distress can be minimized through the use of resilient floor and wall coverings and through the use of closely spaced vertical joints. The performance of a slab foundation can be significantly influenced by landscaping maintenance, recessed landscaping additions near the structures, water line leaks, any other free water sources, and deep rooted trees and shrubs. It is imperative that measures be taken during design and construction to reduce the risk of free water sources near the foundations. See the Appendix to this report to minimize the risk of free water sources and to minimize deep seated soil swell. 9.0 PAVEMENT RECOMMENDATIONS We assume that only occasional heavy to medium truck traffic will be present on the drive areas and that only automobile traffic will be used in the parking pavements. The following recommendations are based upon these assumed conditions. NOTE: Large differential upward slab movements are likely at this site due to soil swelling and should be anticipated. Excavation and moisture conditioning could be performed in pavement areas sensitive to differential movement if it is desired to reduce differential pavement movements. See section 5.5 of this report. Recommdations for this could be provided by AGG based on tolerances for pavement movement determined by the owner. 9.1 SUBGRADE PREPARATION The surficial clay soils are active and have a very high shrink/swell potential. At most sites, clay soils react with hydrated lime, which serves to improve their support value and provide a firm, uniform subgrade beneath the paving. However, this site is underlain by the Eagle Ford Shale Formation. The Eagle Ford clays contain high levels of soluble sulfates whereby the risk for lime-induced heave is unacceptable. 9.2 RECOMPACTED PAVEMENT SUBGRADE The upper eight (8) inches of subgrade soil should be compacted at +1 to +4 percentage points above optimum moisture to a minimum of 96% Standard Proctor density (ASTM D 698). Only on-site soil (comparable to the underlying subgrade soil) should be used for fine grading the pavement areas. After fine grading, the subgrade should again be watered if ALLIANCE GEOTECHNICAL GROUP E12-1106 PAGE 15 needed and re-compacted in order to re-achieve the moisture and density levels discussed above and provide a tight non-yielding subgrade. Sand should be specifically prohibited beneath pavement areas during final grading, since these more porous soils can allow water inflow, resulting in heave and strength loss of subgrade soils. It should be specified that only native day soil will be allowed for fine grading. After fine grading each area in preparation for paving, the subgrade surface should be lightly moistened, as needed, and recompacted to obtain a tight non-yielding subgrade. The subgrade moisture content and density must be maintained until paving is completed. The subgrade should be watered just prior to paving to assure concrete placement over a moist subgrade. Note: The subgrade should be aerated and retested if a rain event occurs prior to paving. Due to the presence of expansive clay soils, large differential upward pavement movements should be anticipated. Inspection during construction is particularly important to insure proper construction procedures are followed. 9.3 DRIVE APPROACHES Water should not be allowed to pond in drive approaches prior to paving. Density tests should be performed on the subgrade soils in each drive approach prior to fine grading in preparation for paving to verify compliance with project specifications. 9.4 PAVEMENT SECTIONS Tables 5 thru 7 present the recommended pavement sections for this project based upon a design life of 20 years: TABLE 5. LIGHT DUTY PAVEMENT SECTION AUTOMOBILE TRAFFIC ONLY (Parking Stalls) PCC SECTION 5 inches Portland Cement Concrete 8 inches Scarified and Compacted Subgrade ALLIANCE GEOTECHNICAL GROUP E12-1106 PAGE 16 TABLE 6. MEDIUM DUTY PAVEMENT SECTIONS MEDIUM DUTY PAVEMENT (Auto Drive Approaches and High Density Travel Lanes with Occasional Truck Traffic) * PCC SECTION 6 inches Portland Cement Concrete 6 inches Scarified and Compacted Subgrade * For less than 25 heavy truck repetitions per week. TABLE 7. HEAVY DUTY PAVEMENT SECTIONS HEAVY DUTY PAVEMENT (Moderate Heavy Truck Use) * PCC SECTION 7 inches Portland Cement Concrete 8 inches Scarified and Compacted Subgrade * * For 75 heavy truck repetitions per week. This Section is also recommended for dumpster pad/service area. The concrete in automobile traffic only areas should have a minimum 28 day compressive strength of 3,000 psi. In truck drive areas, the concrete strength should be increased to 4,000 psi for improved performance and increased serviceable life. Concrete quality will be important in order to produce the desired flexural strength and long term durability. Assuming a nominal maximum aggregate size of 1 inch to 1 3/8 inches, we recommend that the concrete have entrained air of 5 percent (± 1%) with a maximum water cement ratio of 0.44. Proper joint placement and design is critical to pavement performance. Load transfer at all longitudinal joints and maintenance of watertight joints should be accomplished by use of tie bars. Control joints should be sawed as soon as possible after placing concrete and before shrinkage cracks occur. All joints including sawed joints should be properly cleaned and sealed as soon as possible to avoid infiltration of water. Our previous experience indicates that joint spacing on 12 to 15 foot centers have generally performed satisfactorily. It is our recommendation that the concrete pavement be reinforced with No. 3 bars placed on chairs on approximately 18—inch centers in each direction. We ALLIANCE GEOTECHNICAL GROUP E12-1106 PAGE 17 recommend that the perimeter of the pavements have a stiffening curb section to prevent possible distress due to heavy wheel loads near the edge of the pavements and to provide channelized drainage. Eagle Ford shaley clay soils are present at this site and will be in contact with the drilled shafts. The Eagle Ford shaley clay soils typically have very high soluble sulfate levels than can exceed 20,000 ppm. Sulfate levels in excess of 40,000 ppm have been found at some sites. Sulfate resistant concrete mix designs utilizing fly ash are recommended for concrete in contact with these clay soils. The mix design should include the type and amount of cement and the type and amount of fly ash proposed. A locally available fly ash/cement mix design utilizing Type II cement and 25% Type F fly ash or an approved equal is recommended for below grade concrete due to its resistance to sulfate attack. ACI has additional requirements for high sulfate levels (over 20,000 ppm) that should be implemented at this site. 9.5 PAVEMENT CONSIDERATIONS It is recommended that provisions be made in the contract to provide for proofrolling in areas where the subgrade will support new pavements. It is also recommended that an item be included for removal and replacement of soft materials, which are identified by this procedure. Proofrolling can generally be accomplished using a heavy (25 ton or greater total weight) pneumatic tired roller making several passes over the areas. Where soft or compressible zones are encountered, these areas should be removed to a firm subgrade. Wet or very moist surficial materials may need to be undercut and either dried or replaced with proper compaction or replaced with a material which can be properly compacted. Any resulting void areas should be backfilled to finished subgrade in 6 inch compacted lifts compacted to 95 percent of maximum dry density as determined by ASTM D 698 at optimum to +4 percentage points of its optimum moisture content. Achieving the required field density is dependent upon the adequate pulverization of the clay fill materials, the magnitude of compaction energy and the maintenance of field moisture near optimum. All joints and pavements should be inspected at regular intervals to ensure proper performance and to prevent crack propagation. The soils at the site are active and large differential heave within the pavements should be anticipated. Note: See Section 5.5 of report. The service life of paving may be reduced due to water infiltration into subgrade soils through heave induced cracks in the paving section. ALLIANCE GEOTECHNICAL GROUP E12-1106 PAGE 18 This will result in softening and loss of strength of the subgrade soils. A regular maintenance program to seal paving cracks will help prolong the service life of the paving. The life of the pavement can be increased with proper drainage. Areas should be graded to prevent ponding adjacent to curbs or pavement edges. Backfill materials, which could hold water behind the curb, should not be permitted. Flat pavement grades should be avoided. 10.0 EARTHWORK GUIDELINES 10.1 SITE GRADING AND DRAINAGE All grading should provide positive drainage away from the structures, and should prevent water from collecting or discharging near the foundations. Water must not be permitted to pond adjacent to the structure during or after construction. Otherwise, differential foundation movements could exceed estimates contained within this report. Surface drainage gradients should be designed to divert surface water away from the building and edges of pavements and towards suitable collection and discharge facilities. Unpaved areas and permeable surfaces should be provided with steeper gradients than paved areas. Surface drainage gradients within 10 feet of the building should be constructed with a maximum slopes allowed by local code. The roof system should be provided with gutters and downspouts to prevent the discharge of rainwater directly onto the ground adjacent to the building foundations. Downspouts should discharge directly onto well-drained areas or drainage swales, if possible. Roof downspout and surface drain outlets should discharge into erosion-resistant areas. Leave-outs are second-pour strips around columns placed after column erection and adjacent to grade beams placed after compaction of grade-beam backfill. Leave outs for drilled shafts or around the perimeter of the structures should not be allowed to collect and hold water. These leave outs should be pumped out as needed. Water permitted to pond in planters, open areas, or areas with unsealed joints next to the structure can result in on-grade slab or pavement movements, which exceed those indicated in this report. Exterior sidewalks and pavements are subject to some post construction movement. Flat grades should be avoided. Where concrete pavement is used, joints should also be sealed to prevent the infiltration of water. Since some post construction movement ALLIANCE GEOTECHNICAL GROUP E12-1105 PAGE 19 of pavement and flatwork may occur, joints particularly around the building should be periodically inspected and resealed where necessary. 10.2 PROOFROLLING AND SUBGRADE PREPARATION Prior to placing fill, the exposed subgrade in areas to receive fill should be stripped and proofrolled. Soft areas should be undercut and replaced with compacted on site soils. The surface should then be scarified to a depth of 8 inches and recompacted to 95 percent of the maximum density as determined by ASTM D 698 between optimum and +4 percentage points above its optimum moisture content. 10.3 SELECT FILL The material used as select fill should be a very sandy clay to clayey sand (uniform consistency free of clay clods) with a plasticity index between 7 and 15. The fill should be spread in loose lifts, less than 8 inches thick, and uniformly compacted to a minimum of 97 percent of ASTM Standard D 698 between -2% and +2% percentage points of the soil's optimum moisture content. 10.4 ON-SITE CLAY FILL PLACEMENT IN PAVEMENT AND LANDSCAPING AREAS The on—site surficial clays may be used for general grading and filling. The fill materials should be free of surficial vegetation or debris. Clay materials should be spread in loose lifts, less than 8 inches thick and uniformly compacted to a minimum of 95 percent of the maximum density as determined by ASTM D 698 (Standard Proctor) between +3% and +6 percentage points above its optimum moisture content. 10.5 ON-SITE CLAY FILL PLACEMENT IN BUILDING AREAS On-site clay soils may be used as fill in building areas if PTI slabs are used with a design PVR of 3 inches. All fill should be placed and compacted in maximum 8-inch lifts. See Section 8.2 of this report for specification requirements. 10.5.1 MOISTURE CONDITIONING PRIOR TO COMPACTION Each layer shall be leveled with approved equipment. After spreading, each layer shall be thoroughly manipulated by plowing, discing, or other approved methods of the full depth of the layer being placed to insure uniform density and moisture distribution for proper compaction. ALLIANCE GEOTECHNICAL GROUP E12-1106 PAGE 20 LL The moisture content at the time of compaction shall be within the range specified in these special provisions. If the material is too dry, it shall be moistened by watering before and during manipulation, to properly condition the material for compaction. If the material is too wet, the compaction operation shall be delayed until the moisture content has been reduced to within satisfactory compaction range. Because of time of completion limitations, thoroughly processing of the on-site clay soils will be required during manipulation if the moisture content is below optimum at the time of placement. Each fill lift should be processed until the soil mixture is free of large clods to allow uniform moisture distribution and uniform compaction within the entire fill lift. This is particularly important if highly plastic clay soils are to be used as fill in the building pads. The amount of processing and reworking required to achieve uniform moisture conditions can be reduced by pre-wetting the onsite soils prior to placement. 10.5.2 QUALITY ASSURANCE REQUIREMENTS As a quality control measure, pocket penetrometer (P.P.) Tests shall be performed with each field density test during construction as further verification that proper moisture conditioning is being achieved within the clay fill soils. A penetrometer reading between 1.1 tsf and 1.7 tsf will indicate that proper moisture conditioning is being achieved for the clay soils within the upper 10 feet. A penetrometer reading between 1.3 tsf and 2.0 tsf will indicate that proper moisture conditioning is being achieved for the clay soils below 10 feet. Similarly, P.P. tests should be performed on each Proctor Compaction Point in the laboratory for correlation and verification of the desired P.P. range with respect to Proctor moisture, density and swell (with verification that volumetric swell is less than 1% under the proposed select fill surcharge at the targeted moisture content). Prior to construction, it should be confirmed that the "targeted moisture contents" recommended in Section 8.2 will result in an average volumetric swell of less than 1% under the proposed select fill surcharge. This swell testing should be performed in conjunction with all proctor compaction testing. If the targeted moisture contents result in an average swell of over 1% under the proposed select fill surcharge or in a P.P. value outside the range indicated above, Alliance Geotechnical Group should be contacted to determine if the intent of the geotechnical design is being achieved with respect to required swell reduction and bearing capacity. ALLIANCE GEOTECHNICAL GROUP E12-1106 PAGE 21 • y 10.6 FIELD SUPERVISION AND DENSITY TESTING Field density and moisture content determinations should be made on each lift of fill with the minimum of 1 test per lift per 2,500 sf in the building pads (minimum 3 tests per lift per pad), 1 test per lift per 5,000 sf in pavement areas, and 1 test per lift per 100 linear feet of utility trench backfill. Supervision by the field technician and the project engineer is required. Some adjustments in the test frequencies may be required based upon the general fill types and soil conditions at the time of fill placement. Many problems can be avoided or solved in the field if proper inspection and testing services are provided. It is recommended that all footing construction, building pad preparation, pavement construction and site and subgrade preparation be monitored by a qualified engineering technician. Density tests should be performed to verify compaction and moisture content of any earthwork. Inspection should be performed prior to and during concrete placement operations. Alliance Geotechnical Group employs a group of experienced, well- trained technicians for inspection and construction materials testing who would be pleased to assist you on this project. 11.0 LIMITATIONS The professional services that have been performed, the findings obtained, and the recommendations prepared were accomplished in accordance with currently accepted geotechnical engineering principles and practices. The possibility always exists that the subsurface conditions at the site may vary somewhat from those encountered in the boreholes. The number and spacing of test borings were chosen in such a manner as to decrease the possibility of undiscovered abnormalities, while considering the nature of loading, size, and cost of the project. If there are any unusual conditions differing significantly from those described herein, Alliance Geotechnical Group should be notified to review the effects on the performance of the recommended foundation system. The recommendations given in this report were prepared exclusively for the use of client and their consultants. The information supplied herein is applicable only for the design of the previously described development to be constructed at locations indicated at this site and should not be used for any other structures, locations, or for any other purpose. ALLIANCE GEOTECHNICAL GROUP E12-1106 PAGE 22 We will retain the samples acquired for this project for a period of 30 days subsequent to the submittal date printed on the report. After this period, the samples will be discarded unless otherwise notified by the owner in writing. ALLIANCE GEOTECHNICAL GROUP E12-1106 PAGE 23 FIGURES a • 0 ' • , ,: 046,64, Divri'dena Driv ' r°1140,441,4i4'1,4 ; , ,, "., ' ° ''''°•0° ' '" '41 '"'''.ig''J.;; 4 : ...... .... ...... ...... ,........ 4,, . ,,,,,, ,..,.,,...,,, .0,.. „,, , a * 1 . ..., ft.* osatt worekii 110 , :ii tot , . i II , .. 0.1 .., , aot-vo ' a * „,,,,. 1111 t A et Ifflos00 110,01t ,:i. 3 , , VOr'444 1 III 1 0 440 MOO Ategilfr wtor Pa4P B2 0 , . ..... c , ',. 65 ..5 cv 76:il „il 0 C o , N Li \Itt,r, so, Coppell Convention Hotel PLAN OF BORINGS FIGURE 41•1106•00111111•111110.46 ALLIANCE Coppell, Texas GEOTECHNICAL 'F..trd. GROUP Dra\vn a DR (Dale 2/24/12 IRevisedNIA - - Not to scale 1Project No E 1206 '-11 —,.... .., a LOG OF BORING B-1 Project: Coppell Convention Hotel - Coppell, Texas Project No.: E12-1106 Date: 12/17/12 Elev.: Location: See Figure 1 Depth to water at completion of boring: 17 feet Depth to water when checked: was: Depth to caving when checked: was: LLEVATON? SOIL SYMBOLS F DEPTH SAMPLER SYMBOLS DESCRIPTION MC LL PL pi -200 DD PPEN UNCON Str., (feel) &FIELD TEST DA FA °h l °l / pof lsf ksf r2_ ___ Dark olive brown & dark brown shaley CLAY w/ 45++ `calcareous nodules, jointed �J 21 ._._ 455++ — — — Olive, gr,ay &yellowish brown shaley CLAY w/gypsum 4.5+Y crystalsjointed 45++ 45 -5 23 75 28 47 4 5+ ++ 10 0 . : -.. -15 7 -°1411°.;°°# 23 68 25 43 138 3 3 -20 II" -25 r -water seepage @ 29 feet during drilling P Yellowish brown shaley CLAY with weathered shale 2° 30 layers and gypsum crystals, jointed _ A_ -35 0---+r le vi 3 1, Soft to moderately hard dark gray weathered SHALE, Notes FIGURE:2 Alliance Geotechnical Group, Inc. • LOG OF BORING B-1 Project: Coppell Convention Hotel -Coppell, Texas Project No.: E12-1106 Date: 12/17/12 Elev.: Location: See Figure 1 Depth to water at completion of boring 17 feet Depth to water when checked: was: Depth to caving when checked: was: ELEVATION/ SOIL SYMBOLS DEPTH SAMPLER SYMBOLS DESCRIPTION MC LL PL -200 ED P PEN UNISON Strain tfeetl &FIELD TEST DATA % % % ) h pcf tsf ksf % _jointed Moderately hard to hard dark gray SHALE • d0 /50/2" 5011 25" 50/7;' 45 = 1 50/25" —_ 50/5" 50/25" Boring terminated at 50' 55 SO 6.5 -70 Notes. FIGURE:3 Alliance Geotechnical Group, Inc. LOG OF BORING B-2 Project: Coppell Convention Hotel - Coppell, Texas Project No.: E12-1106 Date: 12/18/12 Elev.: Location: See Figure 1 Depth to water at completion of boring: 17.5 feet Depth to water when checked: was: Depth to caving when checked: was: ELEVATION! SOIL SYMBOLS DEPTH SAMPLER SYMBOLS DESCRIPTION MC ll PL Pi -200 OD P PEN UNCON Strain {feet; a FIELD TEST DATA % % % '% pcf tsf ksf --\Olive brown s salty CLAY w/trace of gravel, jointed - - —4 5+r Olive, gray & yellowish brown shaley CLAY w/gypsum 4 5+ crystals, jointed 2 45+_+ +r -- 4 5+i. 4 5++ -5 2` 4 5++ r 21 72 27 45 109 4 5++ 4 5++ 10 ic IC 27 71 27 44 99 4 5++ -20 T —25 040 -water seepage © 27 feet during drilling -30 aaa Soft to moderately hard yellowish brown and dark gray tea- weathered SHALE with gypsum crystals, jointed -35 `-�-�- -7-7— 2C —_ 1 • Notes: FIGURE:4 Alliance Geotechnical Group, Inc. ,,_ LOG OF BORING B-2 Project: Coppell Convention Hotel - Coppell, Texas Project No.: E12-1106 Date: 12/18/12 Elev.: Location: See Figure 1 Depth to water at completion of boring: 17.5 feet Depth to water when checked: was: Depth to caving when checked: was: ELEVATION/ SOIL SYMBOLS DEPTH SAMPLER SYMBOLS MG LL Pt. •200 DO P PEN UNCON Strain (toal7 &FIELD TEST DATA DESCRIPTION h °lo °k HCf 1st k31 f --'_ Moderately hard to hard dark gray SHALE q0 '- 5012.. 50/5" _-_-_- I - k450/t" 4 --- 50/05" -`--' k 50/075' -50 = Boring terminated at 50' -55 -GO -G5 -T0 h cies FIGURE:5 Alliance Geotechnical Group, Inc. LOG OF BORING B-3 Project: Coppell Convention Hotel - Coppell, Texas Project No.: E12-1106 Date: 12/18/12 Elev.: Location: See Figure 1 Depth to water at completion of boring: 17 feet Depth to water when checked: was: Depth to caving when checked: was: ELEVATION! SOIL SYMBOLS DEPTH SAMPLER SYMBOLS DESCRIPTION MC LL PL PI -200 DO PPEN UNCON Strain OW; 3 FIELD TEST DATA % % % pcf 1st ksi P- Olive, gray & yellowish brown shaley CLAY w/gypsum _— 'T.T __ crystals, jointed 22 4 5+ 45++ 36 0001 45 -5 Ir 1 114 22 42 45+ 4 5•+ 4 g++ -10 it 24 70 26 44 15 01111°1 111111-1111- 2G V 1111 -25 -water seepage a@ 27 feet during drilling Yellowish brown and dark gray shaley CLAY with shale — — seams and gypsum crystals, jointed Soft to moderately hard dark gray weathered SHALE, { f sora jointed -35 _7_7_7 50/1 25 _== Moderately hard to hard dark gray SHALE Notes: FIGURE:6 Alliance Geotechnical Group, Inc. $ LOG OF BORING B-3 Project: Coppell Convention Hotel - Coppell, Texas Project No.: E12-1106 Date: 12/18/12 Elev.: Location: See Figure 1 Depth to water at completion of boring: 17 feet Depth to water when checked: was: Depth to caving when checked: was: I ELEVATION/ SOIL SYMBOLS DEPTH SAMPLER SYMBOLS DESCRIPTION r,1C LL PL {,I -200 DD PPER UNCON Shea) (feet) &FIELD TEST DATA �• °k P Is! ksf „ Moderately hard to hard dark gray SHALE 50/S" 40 150/5" - 50/5' 50125" Boring terminated at 45' 50 55 60 { ..70 Notes: FIGURE:7 Alliance Geotechnical Group, Inc. LOG OF BORING B-4 Project: Coppell Convention Hotel - Coppell, Texas Project No.: E12-1106 Date: 12/18/12 Elev.: Location: See Figure 1 Depth to water at completion of boring: 18 feet Depth to water when checked: was: Depth to caving when checked: was: ' ELEVATION/ SOIL SYMBOLS - DEPTH SAMPLER SYMBOLS DESCRIPTION MC LL PL PI -200 DD P PEN UNCON Strain (feel/ &FIELD TEST DATA % % % % pcf 1st ksf oAY Olive brown & dark brown CLAY w/trace of calcareous nodules 16 62 21 41 45,. 4 5•+ 4 5.+ -5 dr,• ` Olive brown CLAY WI gypsum crystals .1y-OrAdiela - 45+.`— __ _ Olive brown, gray &yellowish brown shaley CLAY w/ _ _ 4 5+� ~— gypsum deposits,jointed 20 73 27 46 4 5+. 0 4 5++ —10 ""r 20 a 5-+ 15 0000 _ 23 105 4 5+ 0'3 7 5 -20 0 45 -25 11° I 0411 -water seepage @ 28 feet during drilling J __ Yellowish brown and dark gray shaley CLAY w/shale —25 30 layers and gypsum crystals,jointed r ros, -35 Ill_ ` Notes: FIGURE:8 Alliance Geotechnical Group, Inc. • LOG OF BORING B-4 Project: Coppell Convention Hotel - Coppell, Texas Project No.: E12-1106 Date: 12/18/12 Elev.: Location: See Figure 1 Depth to water at completion of boring: 18 feet Depth to water when checked: was: Depth to caving when checked: was: 1DEPTH SOL SYMBOLS MC LL. PL -200 DD P PEN UNCON Strain I DEPTH SAMPLER SYMBOLS DESCRIPTION t (Feel) &HELD TEST DATAOki °� C % Pc of ksf % Yellowish brown and dark gray shaiey CLAY w/ shale layers and gypsum crystals, jointed 26 -40 Dark gray shaley CLAY, jointed Soft to moderately hard dark gray weathered SHALE; - {,� jointed :t 1 Moderately hard to hard dark gray SHALE 45, --- J5os. --_,-.44 '15 -50 - ---- 15Ur5 -2-:_---`Li50/25' -55 Boring terminated at 55` I -65 -70 E Notes: FIGURE:9 Alliance Geotechnical Group, Inc. • LOG OF BORING B-5 Project Copped Convention Hotel - Coppell, Texas Project No.: E12-1106 Date: 11/18/2012 Elev.: Location: See Figure 1 Depth to water at completion of boring: Dry Depth to water when checked: end of day was: Dry Depth to caving when checked: was: LLEVATION/ SOIL SYMBOLS DEPTH SAMPLER SYMBOLS DESCRIPTION MC LL PLPI .200 DD PPEN UNCON Strain I (feel) &FIELD TEST DATA % % % % pcf sf ksf Olive gray, gray & yellowish brown shaley CLAY WI 45`1 gypsum crystals, jointed 1e 45+. 4 5+. 22 1731 30 49 108 4 5+. 4 5+. '-5 45++ _I 4 5++ 45+4 --10 '41 014-11#1 21 71 24 47 107 4 5+4 (-15 F 201 25 75 25 50 102 4 5-+ -25 Boring terminated at 25' -30 -35 FIGURE:10 Alliance Geotechnical Group, Inc_ ♦ • KEY TO LOG TERMS & SYMBOLS Symbol Description Symbol Description Strata symbols m THD Cone /// Penetration CLAY, Test shaley SHALE, 47-7weathered = SHALE r/-2L CLAY Misc. Symbols Water table at boring completion Boring continues Soil Samplers Thin Wall Shelby Tube Auger Notes: 1. Exploratory borings were drilled on dates indicated using truck mounted drilling equipment. 2. Water level observations are noted on boring logs. 3. Results of tests conducted on samples recovered are reported on the boring logs. Abbreviations used are: DD = natural dry density (pcf) LL = liquid limit (%) MC = natural moisture content (%) PL = plastic limit (%) Uncon.= unconfined compression (tsf) PI = plasticity index P.Pen.= hand penetrometer (tsf) -200 = percent passing #200 4. Rock Cores REC = (Recovery) sum of core sample recovered divided by length of run, expressed as percentage. RQD = (Rock Quality Designation) sum of core sample recovery 4" or greater in length divided by the run, expressed as percentage. FIGURE:11 Affiance Geotechnical Group, Inc. V J SWELL TEST RESULTS ATTERBERG IN-SITU FINAL BORING DEPTH UNIT LIMITS LOAD °/0 NO. (FEET) WEIGHT MOISTURE MOISTURE VERTICAL LL PL PI CONTENT CONTENT (PSF) SWELL 7 8-2 7-8 109.1 72 27 45 20.9 27.1 938 9.6 B-2 19-20 99.0 71 27 44 27.1 28.7 2,438 2.1 8-5 3-4 107.8 79 30 49 21.7 31.2 438 16.2 B-5 14-15 106.9 71 24 47 21.4 25.4 1,813 5.5 B-5 24-25 102.4 75 25 50 24.9 25.7 3,063 0.8 PROCEDURE: 1. Sample placed in confining ring, design load (including overburden) applied, free water with surfactant made available, and sample allowed to swell completely. 2. Load removed and final moisture content determined. SWELL TEST RESULTS COPELL CONVENTION HOTEL COPELL,TEXAS ALLIANCE GEOTECHNICAL GROUP E12-1106 Date: 12/24/12 FIGURE 12 APPENDIX MEASURES TO MINIMIZE DEEP-SEATED SWELL APPENDIX MEASURES TO MINIMIZE DEEP SEATED SWELL In order to reduce the risk of excessive upward ground movements caused by soil swelling associated with free water sources, the following measures should be taken during design and construction: • The use of superior contractors and utility line materials accompanied with Quality Control inspection and testing of all utility line installations including automatic sprinkler systems installed after construction. • Sprinkler lines should not be installed near the structure. Instead, the system should be designed so that the lines themselves are as far away from the structure as possible. Sprinkler heads should be used with a capacity to direct water toward the structure from distances of several feet. • Utility under-drains with impervious barriers along the trench bottom may be used as an additional safeguard to minimize post-construction upward movement caused by water percolation into the deeper clay soils. • Elevated landscape beds over impervious lining should be used in lieu of recessed beds to prevent ponding water conditions near the structure. • If swimming pools are to be constructed at this site, specific recommendations for design of all swimming pools, pool decking, and all other flatwork should be provided by Alliance Geotechnical Group to minimize the potential of destructive damage caused by soil movements. • Positive drainage should be provided. Surface drainage gradients within 10 feet of the building should be constructed with maximum slopes allowed by local codes. • Roof gutters should be used to direct roof runoff away from the structure in the most direct manner. Downspouts should not be allowed to discharge into landscaped areas located near the building. Downspout extensions should be used to facilitate drainage from the structure. • Rapid repair of any utility leak including water lines, sewer lines, sprinkler line, sprinkler heads. • Trees and deep rooted shrubs should be located no closer to the structure than one- half their ultimate mature height to reduce foundation settlement effects caused by moisture absorption of the root systems. If the risk of large additional deep-seated swell is not desired, pier foundations in conjunction with structural floors should be used in areas sensitive to movement. ALLIANCE GEOTECHNICAL GROUP E12-1106