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Northlake 635(4)-SY 980925PROJECT NO. 4814 REPORT NO. 1 SEPTEMBER, 1998 GEOTECHNICAL INVESTIGATION COPPELL TECH CENTER 1I CRESTSIDE DRIVE AND L4,KESHORE DRIVE COPPELL, TEXAS Presented To: CMC - COMMERCL~kL REALTY GROUP DALLAS, TEXAS September 25, 1998 Project No. 4814 Report No. 1 CMC - Commercial Realty Group One Lincoln Centre 5400 LBJ Freeway, Suite 1450 Dallas, Texas 75240 ATTN: Mr. Subash Gaitonde GEOTECHNICAL hNVESTIGATION COPPELL TECH CENTER I1 CRESTSIDE DRIVE AND LAKESIIORE DRIVt; COPPELL, TEXAS Gentlemen: Transmitted herewith are copies of the referenced report. Should you have any questions concerning our findings or if you desire additional information, please do not hesitate to call. Sincerely, REED 1~NGINrEERII',.~,~BObq~, INC. // ' X.,ice.~resident Ronald F. Reed,' - ' P.E. ~".." '~, .... .76' · . . ~,~. '.~'~ Pnnc~pal Engineer $ :. "~ '. ,'~ ........ '...~ FWS;RFR/aap ~ laON.N_~...F..fi..~.~.; :.?"-z~ cop'es submitted: ( .'1 l.~:. t .... ~ .5,, · I- ~'o' -. ,~-et~ ~.' ~ HEED E n r- I I--'1 '-~" E F:I I I'"1 r~- ............................................................... TABLE OF CONTENTS PAGE INTRODUCTION ................................................................................................ 1 Project Description ................................................................................... 1 Authorization ............................................................................................ Purpose and Scope ................................................................................... 1 FIELD AND LABOIL-kTORY IxNVESTIGATIONS ........................................... 2 General .................................................................................................... 2 Field Investigation .................................................................................... 2 Laboratory Testing ................................................................................... 3 GENERAL SITE CONDITIONS ........................................................................ 4 Geology. .................................................................................................... 4 Stratigraphy .............................................................................................. 4 Ground Water .......................................................................................... 5 Texas Natural Resource Conservation Commission (TNRCC) Comment .......................................................... 5 ANALYSIS AND RECOMMENDATIONS ....................................................... 6 Potential Vertical Movements .................................................................. 6 Foundation Design .................................................................................... 7 Grade Beams/'I'ilt-Wall Panels ................................................................. 9 Floor Slab .................................................................................................. 10 Earthwork ................................................................................................. 13 Pavement ................................................................................................... 14 Construction Observation and Testing Frequency. ................................ 16 -i- TABLE OF CONTENTS (Continued) ILLUSTRATIONS PLATE PLAN OF BORhNGS ........................................................................................... 1 BORLNG LOGS ............................................................................................... 2-6 KEYS TO TEILMS AND SYMBOLS USED .................................................... 7&8 LABORATORY TEST RESULTS ..................................................................... 9-I 1 ABSORPTION PRESSURE-SWELL TEST RESULTS .................................... 12-14 SPECIFICATIONS PAGE WATER INJECTION WP'SELECT" FILL CAP OPERATIONS .................... 1 WATER INJECTION W/LIME-MODI'FI_ED CAP OPERATIONS ................. 1 WATER AND LIME INJECTION OPEIL, kTIONS ........................................... I - ii- INTRODUCTION Project Description This report presents the results of a geotechnical investigation performed for the proposed Coppell Tech Center II to be located northwest o£ the intersection of Lakeshore and Crestside Drives in Coppell, Texas. The project consists of an 80,071-square foot office building with associated parking and dr/yes. The general orientation of' the building is shown on the Plan of' Borings, Plate 1 of'the report Illustrations. Tilt-wall construction with brick facing, or concrete block construction on grade beam is anticipated. The use of pier foundation support in conjunction with a ground-supported "floating" floor is also anticipated. Authorization This investigation was authorized by Mr. Subash Gaitonde of CMC - Commercial Realty Group on August 11, 1998. Purpose and Scope The purpose of this investigation has been to evaluate the general subsurface conditions and provide recommendations for: · design of the foundation system; · floor slab; · pavement subgrade; and · site preparation and earthwork compaction criteria. Project No. 4814/Report No. 1 - I - September 25, 1998 The investigation has included drilling sample borings, performing laboratory testing, engineering and geologic analyses, and development of geotechnical recommendations. The follov,4ng sections present the methodology used in this investigation. Recommendations provided herein are site-specific and were developed for the project discussed in the report Introduction. Persons using this report for other than the intended purpose do so at their own risk. FIELD AND LABOIL4,TORY INVESTIGATIONS General The field and laboratory investigations have been conducted in accordance with applicable standards and procedures set forth in the 1998 Annual Book of ASTM Standards, Volumes 04.08 and 04.09, "Soil and Rock, Geosynthetics". These volumes should be consulted for information on specific test procedures (see ASTM D-1587). Field Investigation Subsurface conditions were evaluated by five sample borings drilled to depths of 30 feet in August, 1998. The approximate locations of the borings are shown on Plate 1 of the report Illustrations. Borings were advanced between sampling intervals by means of a truck-mounted drilling rig equipped with continuous qight augers. Samples of cohesive soils and shale were obtained with three-inch diameter Shelby tubes. Project No. 4814/Report No. I - 2 - September 25, 1998 Delayed water level observations were made in the open boreholes to evaluate ground water conditions. Borings were backfilled at completion of field operations. Sample depth, description of materials, field tests, water conditions and soil classification [Unified Soil Classification System (USCS), ASTM D-2488] are presented on the Boring Logs, Plates 2 through 6. Keys :o terms and symbols used on the logs are included as Plates 7 and 8. Laboratory Testing All samples were returned to the iaboratoD' and visually logged in accordance with the USCS. The consistency of cohesive soils ,,vas evaluated by means of a pocket penetrometer. Results of the pocket penetrometer readings are presented on the boring logs. LaboratoD' tests were performed to evaluate index properties, confirm visual classification, and evaluate the undrained shear strength of selected samples. Tests and ASTM designations are provided in Table 1. TABLE 1 TESTS CONDUCTED AND ASTM DESIGNATIONS Tyoe of Test ASTM Designation Atterberg Limits D-4318 Moisture Content D-2216 ,'""' D-5298 Soil S.,..un I I Unconfined Compression (Soil) i D-2166 The results of these tests are summarized on Plates 9 through 11. Project No. 4814,rR. eport No. I -3- September 25, 1998 The expansive characteristics of the upper soils and weathered shale were also evaluated by means of absorption pressure-swell tests~. Results of the swell tests are presented graphically on Plates 12 through 14. GENERAL SITE CONDITIONS Geology The site is located within terraced alluvial soils overlying xveathered and unweathered shale of the Cretaceous Eagle Ford Formation. The terraced alluvial soils are associated wit},, Quaternary deposition in the floodplain of the Elm Fork Trinity River and its tributaries in the geologic past. In its unweathered state, the Eagle Ford Formation typically consists of a dark gray, soft clay shale which weathers to form a highly plastic material with the engineering properties of a CH clay. Stratigraphy Subsurface conditions encountered in the borings consist of allu~qal soils overl54ng weathered and unweathered shale. The alluvial soils consist of very' dark grayish-brown to grayish-brown and dark yellowish-brown, high plasticity clays with vao'ing quantities of sand, calcareous particles and ironstone fragments. ~ Johnson, L.D., & Snethen, D.tL (1978). "Prediction of Potential H~ve of Swelling Soil.~ Geotechnical Testing Journal. ASTM 1 (3), 117-124. Project No. 4814/R. eport No. 1 - 4 - September 25, 1998 The alluvial soils extend to depths of' eight to nine Feet and are underlain by dark yellowish- brown to yellowish-brown and gray, severely weathered to weathered shale. The degree o£ weathering decreases with depth. The weathered shale possesses the engineering properties of'a CH clay and is, therefore, classified as such on the boring logs. Dark gray, soft, slightly silty, unweathered shale was encountered below depths of 27 to 29-1/2 feet in Borings B-1, B-2, and B-4. The remairfing borings terminated within the weathered shale at depths of 30 feet. Based on the field and laboratory data, the soils were relatively moist below' depths of about 8 to 10 feet at the time of the field investigation (August, 1998). Ground Water Based on post-drilling water level obser~'ations, ground water was present at depths of about 8 to 11 feet in Au~st, 1998. The ground water is perched above the relatively, impermeable, unweathered shale in the overlying weathered shale and alluvial soils. Quantities are generally anticipated to be limited. The depth to ground water will fluctuate with variations in seasonal and yearly rainfall. Texas Natural Resource Conser~'ation Commission (TNRCC) Comment The TNRCC adopted regulations, known as "Subch.~pter T," on April 19, 1995, pertaining to land development over closed municipal solid waste landfill units. The site observations and subsurface data do not indicate the presence of buried municipal solid waste at this site. Based on this data, development of this site will not require Subchapter T permitting. Project No. 4814/Report No. 1 - 5 - September 25, 1998 ......................................... ANALYSIS AND RECOMMENDATIONS Potential Vertical Movements Potential Vertical Movements 0VVM) were evaluated using an empirical procedure developed by McDowell2 and modified by the Texas Department of Transportation, TxDOT Test Method 124-Ea in conjunction with the soil suction and absorption pressure-swell tests. As previously noted, the clays were relatively moist below depths ofabout 8 to 10 feet in August, 1998. Based on the P\,'M calculations and past experience, potential movements are estimated to be on the order of four to six inches. Movement will be associated with seasonal changes in soil moisture within the upper 8 to 12 feet Ground-supported improvements (i.e., sidewalks and paving) x¥fll move in response to changes in soil moisture. The movement will be observed as heave if the soils are dry at the time the pavement or sidewalk is constructed. The movement will be observed as settlement if the soils are moist at the time of constrdction. Generally, settlement will be limited to the outer perimeter (outer four to five feet) of larger slabs. Settlement can be controlled by prudent watering during extended dr)' climatic periods. Recommendations are provided to limit movement below the building; however, some movement of site paving and sidewalks should be anticipated. : McDowell, C. "The Relation of Laboratory Testing to Design for Pavements and Structures on Expansive Soils". Quarterly of the Colorado School of Mines, Volume 54, No. 4, 127-153. 3 "Method for Determining the Potential Vertical Rise, PVR." (1978). Texas Department of Transportation, Test Method Tex- 124.-E. Project No. 4814/Report No. 1 - 6 - September 25, 1998 The estimated PVM' is based on existing site grades. If signific~t cut m~d fill will be required below the building to establish finished grade, this office should be consulted for additional analysis and recommendations. Foundation Design Foundation support for concentrated column loads should be provided by reinforced concrete, underreamed (belled) piers. The piers should be founded at a depth of 15 feet below existing (April, 1998) gra,des, within the yellowish-brown and gray clays (weathered shale). The piers should be designed for an allowable bearing pressure of seven kips per square foot (ksf). Piers proportioned in accordance with the allowable bearing value will have a minimum factor of safety of three considering a shear or plunging failure. The weight of the pier concrete below final grade may be neglected in determining foundation loads. Properly constructed underreamed piers should not undergo post-construction settlements in excess of 1/2 inch. Piers will be subjected to uplift associated with swelling within the upper clays. The piers should contain reinforcing steel throughout the pier to resist the tensile upliR forces. Reinforcing requirements may be estimated based on an u?lift pressure of 1.5 ksfacting over the top 10 feet of pier surface area. The calculated uplift va!ue is considered a working load. Appropriate factors of safety should be applied in calculating tile percent of reinforcement. Project No. 4814/R. eport No. I 7 September 25, 1998 "Mushrooming" or widening of the upper portion of the pier shafts will significantly increase the uplift pressure from the upper clays. "Mushrooms" should be removed from the piers prior to backfill operations. Pier caps should not be used with the piers unless a minimum void of six inches is created below the portion of the cap emending beyond the shaft diameter. This void is applicable considering implementation of subgrade modification as outlined in the Floor Slab section. Uplift resistance for underreamed piers will be provided by the weight of the soil overl54ng the bell and the dead load from the structure A minimum bell-to-sha?t diameter ratio of two to one (2:1) is recommended to resist uplift associated with sw'elling of the upper soils. A maximum bell-to-shaft diameter ratio of 3: 1 is recommended from construction consideration. Due to presence of ground water, close coordination of drilling and concrete placement should be performed to minimize the need for dewatering Dependent upon site conditions, pier depths may be raised (at the direction of the engineer) to avoid ground water. Pier excavations should be do, and free of deleterious materials prior to concrete placement. In no case should the pier shaft excavations remain open for more than four hours prior to concrete placement. Project No. 4814/'Report No. I - 8 - September 25, 1998 Continuous obserYation of the pier construction by a representative of this office is recommended. Observation is recommended to confirm the bearing stratum and that the excavations are dr3' prior to placement of concrete. Grade Beams/Tilt-Wall Panels Grade beams or tilt-wall panels should be constructed with a minimum void of six inches. This void is applicable considering subgrade modification as described in the following Floor Slab section. A void is recommended to limit potential foundation movements associated with swelling of the underlying soils. The void can be created below grade beams by use of wax-impregnated cardboard forms, or beneath tilt panels by over-excavating the required void space prior to panel erection. Retainer boards along the outside of the grade beams or tilt-wall panels should not be necessary. Grade beams should be double-formed. Earth-forming of beams below ground is not recommended because of the inability to control the beam excavation width. Fill on the outside of perimeter grade beams and'or tilt walls should be placed in a controlled manner. Bac'~ll should consist of site-excavated clays, or equal, placed and compacted in accordance with the Earthwork section. Ifbedding soils must be used adjacent to the perimeter of the building, the clay/bedding soil interface should be sloped to drain away from the building. Compaction criteria are included in t?,e Earthwork sect[on. Project No. 4814/Report No. I - 9 - September 25, 1998 Floor Slab Potential movements associated with heave £rom a dry condition to a moist condition are estimated to be on the order of four to six inches. Additional movement is possible if the clays become saturated, such as can happen from utility leaks and excessive ponding adjacent to the perimeter walls. Two types of floor systems are considered feasible; a suspended floor, and a ground-supported (or "floating") slab. The suspended floor is considered the most expensive, but does provide the highest degree of confidence that post-construction movement cf the floor will not occur. If this alternative is desired, a minimum void o~12 inches (appro×imate F.S. of 2) is recommended Use of a ground-supported floor is feasible, provided the ri3k of some post-construction floor movement is acceptable. The potential movement can be reduced by proper implementation (i.e., construction) of remedial earthwork recommended in the following paragraphs. The risk of the potential movement occurring can be reduced by implementation of positive grading of surface water away from the building and backfilling immediately adjacent to the structure ,,,,4th on-site clays. Considering a finished floor elevation close to existing grades, the most economical means of limiting the potential for post-construction floor movement is to preswell the upper clays via water pressure i~iection then provide a surface seal with either 12 inches of"select" fill or a Project No. 4814/Report No. 1 - 10 - September 25, 1998 lime-stabilized cap. The lime-stabilized cap can be provided by either of two ways; scarification of approximately four percent lime into the top six inches of subgrade at completion of preswelling, or integration of one pass of lime with the water pressure injection passes. General procedures are presented in the following paragraphs. 1. Cut and fill balance to within 12 inches of finished subgrade with on-site soils, or to subgrade if the lime-stabilized cap option is desired. Place and compact soils in accordance with recommendations in the Earthwork section. · Note: If insufficient on-site fill exists to achieve proposed subgrade for the "select" fill option, all imported fill for use below the building should consist of "select" soils. Balance on-site soils to provide a uniform thic'kness of selec, 2. Preswell the upper clays via pressure injection with water to a depth of 10 feet. Guideline specifications for performance of' the injection are included in the report Specifications. 3. Place and compact the surface moisture barrier, consisting of 12 inches of "select" soil or a lime-stabilized cap. As discussed above, the lime cap may consist of either four percent hydrated lime scarified into the top six inches of injected soil, or one pass of lime may be substituted for one of the water injection passes. Placement recommendations for "select" fill are included in the Earthwork section. Guideline specifications for all three options, "select" fill, lime cap, and lime injection are provided in the report Specifications. Injections should be extended a minimum cf five feet beyond the general building lines. The injection should be increased to 10 feet beyond the buildii:.g at entrances and docks to lin-tit the potential for ditTerential movement bezween the structure and sidewalks or entrance pavement. Project No. 4814/Report No. 1 11 - September 25, 1998 The performance of an injected subgrade is dependent upon the quality of the workmanship. Therefore, water pressure injection is not recommended unless a representative of this office is present full-time to observe all injection operations. The actual number of injection passes required will be dependent upon the soil moisture conditions at the time of construction. For estimating purposes, and considering relatively dry conditions at the time of construction, a minimum of four injection passes should be anticipated. The surface moisture sea! should be constructed as soon as possible after completion of injection operations to ~imit moisture loss within the upper clays. Potential floor movements considering a properly preswelled subgrade are anticipated to be on the order of !/2 to 1 inch. Positive drainage of water away from the structure must be provided and maintained after construction. Architectural detailing of interior finishes should allow for approximately 1/2 to 1 inch of differential floor movement. A moisture barrier (minimum 6-mil polyethylene) is recommended below a ground-supported floor. This is of particular importance below sections of the floor covered with carpeting, paint, or tile. Ground-supported floors over expansive soils may be subject to settlement if the underly4ng clays dry during the life of the st,~cture. Natural desiccation will be limited to the outer four to five feet along the perimeter. Roots f:om trees and shrubs can however grow below the Project No. 4814,rReport No. 1 - 12 - September 25, 1998 structure and increase the zone of'desiccation. This process typically requires 8 to 10 years to develop. An effective means of limiting plant root growth is construction of a vertical moisture barrier adjacent to the foundation, or extension of paving to the perimeter of the building. The barrier, if utilized, should consist of a minimum six-inch wide, five-foot deep lean concrete wall. Trees and shrubs should be planted outside the barrier. Earthwork All vegetation and topsoil containing organic material simuld be cleared and grubbed at the beginning of earthwork construction. Areas of the site which will underlie fill or within the building should be scarified to a depth of'6 inches and recompacted to a minimum of 92 percent and a maximum of 98 percent of the maximum density as determined by ASTM D-698, "Standard Proctor". The moisture content should range from +1 to +5 percentage points above optimum. Site-excavated soils, ,.,,,here used as fi!l, should be placed in maximum eight-inch loose lifts and compacted to the moisture and density requirements outlined above. The final 6 inches of subgrade below pavement should be compacted to a minimum of 95 percent of Standard Proctor, at or above optimum moisture. Project No. 4814/Report No. I - 13 - September 25, 1998 Proper backfilling around the building perimeter will reduce the potential for water seepage beneath the structure. Fill against the perimeter of the foundation should consist of site- excavated clays, or equal, and should be placed and compacted in accordance with the recommendations outlined above. "Select" fill is defined as a uniformly blended clayey sand with a Plasticity Index (PI) of between 4 and 15. Select fill should be placed in maximum 8-inch loose lifts and compacted to at least 95 percent of ti~e Standard Proctor density, at a moisture content between -2 to +3 percentage points of optimum. The select fill should be placed as soon as possible over the injected subgrade to limit moisture loss within the underlying soils. Pavement Concrete pavement is anticipated for both car and light truck parking, and for drives and se~,ice areas. In general, stabilization of the subgrade is not cost-effective when using rigid pavement, and does not sigrdficantly increase the load-carrying capacity of the pavement. Stabilization does however pro~Ade a construction or working pad, and may be advantageous from this perspective, especially if construction occurs during the wetter portions of the year. Stabilization is ho'~,-ever recommended iftra~c speeds will exceed 30 miles per hour (mph). Project No. 4814/Report No. I 14 - September 25, 1998 The specific pavement sections will be dependent upon the type and frequency of traffic. For drives and parking subject to cars and light trucks, a 5-inch thick, 3,000 pounds per square inch (psi) compressive strength pavement section constructed over a subgrade scarified and recompacted as outlined in the Earthwork section should provide for unlimited repetitions over a 20-year life. For drives and ser¥ice areas subject to the equivalent of four or less loaded semi-trucks per day and within fire lanes, a minimum 6-inch thick, 3,000-psi compressive strength pavement section is recommended The pavement should be constructed over a subgrade scarified and recompacted as discusse~ in the Earthwork section. Pavements should be lightly reinforced to control shrinkage cracks. Reinforcing should consist of the approximate equivalent of #3 bars at 24 inches on-center. The specific amount of steel should be determined based on spacing of expansion, construction and contraction (saw)joints. Pavement sections should be saw cut at an appro.,dmate spacing in feet of 2.5 to 3 times the pavement thickness expressed in inches. (For example, a 5-inch pavement should be saw cut in approximate 12.5 to 15-foot squares.) The actual joint pattern should be carefully designed to Project No. 4814/Report No. I - 15 - September 25, 1998 avoid irregular shapes. Recommended jointing techniques are discussed in detail in "Joint Design for Concrete Highway and Street Pavements", published by the Portland Cement Association4. Construction Observation and Testing Frequency It is recommended that the following items (as a minimum) be observed and tested by a representative of this office during construction. Observation: · Fill placement and compaction. · Pressure injection operations. · Pier construction and concrete placement. Testing: · Earthwork · One test per 5,000 s.£ per lift within fills below the building. · One test per 10,000 s.f. per lift within fills in the paving area. · One test per 150 linear &et per lift in utility and grade beam backfill. · Post-injection borings, one boring per 10,000 s.f. of injected area. The purpose of the recommended obserYation and testing is to confirm the proper foundation bearing stratum and the earthwork and building pad construction procedures. 4 "Joint Design for Concrete Highxvay and Street Pavements" (1980). Portland Cement Association, Skokie, IL. Project No. 4814/Report No. 1 - 16 - September 25, 1998 reed engineering GROUP Coppell Tech Center II Project NO. 4814 Crestside Drive and Lakeside Drive Bate: 08-21-g8 Coppell, Texas Location: See Plate '" CORE Pocklt Plnetro~eter Standard Penetration Tests '~ ~ DESCRIPTION OF STRATA ~o~ per Foot - + m O- CLAY, very dark ~rayish-bro~n, hard, w/trace of weathered, calcareous particles gcoarse, quartz sand (CH) 5- CLAY, grayish-brown, very stiff, " / w/trace of calcareous particles ~ mmeral~zation (CH) / / CLAY, yei~owish-brown w/some gray, lO- very (severelyweathereo shale) (CH) very ~tiIf to hor~. ~lockg, ~li~htly 15- (weathered shale) (CH) / 20- 25- . :::fi:~ S~ALE, dark gray, soft, slightly silty 30- ~ Total Depth - 30 feet 35- BORING LOG B-1 PLATE 2 ~-~ ~-. reed engineering GROUP Coppell Tach Center I! Proiect No, 48;4 Crestside Drive and Lakeside Orive Date: 00-OI-08 Coppell, Texas Location: See Plate "' CORE PoCke{ Pene[rometer Readings > u~ ~ Tons Per S~I. FL ~ ~ ~ DESk[PT[ON ~ STRATA ao.s per Foot ~ ~ ~ ~ ~ ! 2 3 4 o- ~ CLAY, dark grayish-brown, hard.  ~/trace of calcareous particles ICH) 5- ~ ~/trace of ironstone fragments belo~ CLAY, yellowish-brown ~/gray, har~ _ t0- (severe,y ~eathered shale) (CH) CLAY, yellowish-brown w/trace of gray, ,5- hard, blocky, slightly silty, w/traceofmineralization (weathered shale) CCH) , / 30- -'~ SHALE, dark gray, soft, slightly silty /-- ~ - Total Depth ,' 30 feet Dry @ completion. Hater ~ 8-1/2' & blocked 35- @ 9' .m 09-04-98. BOR!NG LOG B-2 PLATE 3 6EOTEI~-I~CN. CONSULT~ _ reed eno~g " GROUP Coppell Tech Center I! Proiect No. 4814 Crestside Drive and Lakeside Drive Date: 08-01-88 Coppell, Texas Location: See Plate ! cu CORE Pocket I'e~e~*o~eter Readings ~ ~ ~ ~ DES~IPTION ~ STRATA ~ow~ ~ F~t- + I I 2 3 4 O- CLAY. Uark oFay)sh-bFown, hard, w/trace of calcareous parUcles (CH) 5- (:;ark yellowish-brown belOw 5' - CLAY, dark yellowish-brown 10- w/yellowish-brown (;; trace of dark gray, hard, lam;niated, blocky, slightly silty (weathered shale) (CH) 15- *~" CLAY, yellowish-brown to olive-brown w/trace of gray. very stiff to hard. blocky, slightly silty, w/trace of 20- minerslization (CH) _~. ,See>a~;e (~ur ng dr, lin;i/ - / / - 30- Total Oep[h ' 30 feet Seepage encountered ~ 20' during drilling. ~aJer ~ 8' ~ blocked J 22' on 09-04-g8. 35- BORING LOG B-3 PLATE 4 ~ ~T~ -' -- ..-. - reed engineering Coppell Tech Center II GROUP Project No. 4814 Crestside Drive and Lakeside Drive Date: 09-01-98 Coppell, Texas Location: See Plate cu CORE Pocket Penetrometer Readings ~ ol co Tons Per 54. FL -! ~.~ ~ = ~ ~ St.da,d Pe. traUon O- CLAY, very dark Grading to dark grayish-brown, hard. w/trace of calcareous particles (CH) 5- CLAY, grayish-brown C, yellowish-brown w/trace of gray, hard, w/trace of calcareous &ironstone particles (CH) / / ~AY, yellwoish-brown w/trace of gray 10- [; brownish-yellow, hard, blocky, slightly ~,~ siity, w/trace of mineralization [weathered shale) (CH) 30- -~ SHALE, dark gray, soft, slightly silty /-- ~ - Total Depth - 30 feet Water O 6-1/2' G blocked @ 18-1/2' on 35- 09-04-98. BORING LOG B-4 PLATE 5 6E~ I:~NSULTANTS Coppell Tech Center I! GROUP.. Project No. 4814 Crestside Drive and Lakeside Drive Date: og-oI-g8 Coppell, Texas Location: See Plate '" CORE Pocket Penetrometer Readings ~ u~ m Tons Per S4. FL -! ~ ~ ~ ~ DESk[PT[ON ~ STRATA ao.s ~er F~t - * ~ g I 2 3 4 ~ ~ O- CLAY, very dark gray, hard. ~/trace of calcareous particles (CH) E 5- CLAY, grayish-brown w/trace of ~ . i yeliowish-brown, hard, w/trace of / calcareous G ironstone particles (CH) / CLAY, yellowish-brown w/trace of / ~ browmsh-yeHow, hard, blocky IO- I,j (se~'erely weathered shale) (CH) ~,~ SHALE, yellowish-brown w/trace of gray, hard, blocky, slightly silty, ~\ w/trace of mineralization 15- (weathered shale) (CH) 20- ~- ,~ See)a[e Cur ng Or lin'J. / 30- E Total Oepth = 30 feet Seepage encountered ~ 26' during drilling, Nater @ 27-1/2' after 5 minutes. Nater 0 I1' G blocked @ 21-I/2' on 09-04-98. 35- BORING LOG B-5 PLATE 6 ~ -- reed engineering GROUP reed engineering GROUP .... Coppell Tech Center [! Project No. 4814 Crestside Drive and Lakeside Drive ~j Fa Date: 08-21-98 Coppell, Texas Location: See Plate 1 ~k/Y~ Type of - -- Tons P~ ~cl. Ft -~ O.AY  j~ Star~tard Pe.~t~at~n Tests (~.<50) m ~ ~ ~ I Z 3 4 45+ 4.5++ O~ CLAY, verydark grayish-brown, . ~ ~>~)  hard, ~/trace of weathered, :~__ calcareous part,cle5 ~ coarse, ..  ousrtz san~ (CH) SILT ~) '~ CLAY, gray,sh-brown, very st,fl.' /~- ~ (~<~) ' ~ w/trace of calcareous parhcles ~ m'.~era.~:5;cn ~CH) SILT (~) s,:t, J ~ ~ ~AYEY SANO ~5-- gr3/, +e',' 5' ~ t3 h9ra. D'.ocky, J SJLTY SA~ sl.~r-tW s:ity j i~e~therea Shale] (CH) J [sP-sw) ~AY~ ~VEL j , 30 - ' ~ - ~2~ (unweat~rec: J Tota~ Dectr. = 33 feet ~ L~STO~ {un~eat~e~) ~sJ I BORING LOG B-1 F;ATE 2 ~:,:~ (~weat~c) ~-C~e) TEST ~ = wat~ ~e a: t~e of ~g.  ~ ~ ~ ~ = Svbse~ent wat~ le,~ ~ Cate. . ~ TEST KEYS TO SYMBOLS USED ON BORING LOGS PLATE 7 I~OT~ cocSUlT~rrs GROUP SOIL PROPERTIES COHFS[ONLFSS SOILS COHFS[VF SOILS SPT Pocket NIValues Relative Penetrometer (blows/foot) Density (T.S.F.) Consistency 0 - 4 ...................... Very Loose <0.25 .............. Very Soft 4 -I0 ......................... Loose 0.25-0.50 ............Soft 10-30 ...................... Nedi~m Dense 0.50-L00 .............Hedium Stiff 30-50 ....................... Dense 1.00-2.O0 ............... Stiff 50 + ......................... Very Der,se 2.00-4.00 ............. Very Stiff 4.00 + .................. Herd ROCK PROPERTIES HARDNF,~,~ RIAGNO,~TIC FFATURF,~ Very Soft .......................... Can be dented with moclerate finger pressure. Soft ................................. Can be scratched easily ~ith fingernail. Hoderately Hard ............. Can be scratched easily with knife but not with fingernail Hard ................................. Can be scratched ~ith knife ~ith some difficulty; can be I:h'oken by light to moderate hammer blow. Very Hard ........................ Cannot be scratched ~ith k~',ife; can be broken by repeated heavy hammer blows. FF'~ OF WF'ATI.-iF~,~ DiAGNOSTiC FFATURFS Slightly Heathe~ed ..............Slight discoloration i~arct~ from open fractures. ~leathered. ............................ ~scoloretion th,'ouGhout; ~eeker mine~els decomposed; strength sc. aether than fresh rock; struclCre preserved. Severely Heathered .......... Host minerals somewhat deco~.c)oses; much softer th,~n fre~ rock; texture becoming In~sl, inct l~l fa~ic and structure I~'eservect. Completely Heathere,3 ....... N;nerals ~ecomposeO to so;i; rock fabric and sb'ucture Qestroye~l (residua~ soil). KEY TO DESCRIPTIVE TERNS ON BORING LOGS PLATE 8 6EOTE~ COI~TANTS GEOTECHNlCAL INVESTIGATION COPPELL TECH CENTER II CRESTSlDE DRIVE AND LAKESHORE DRIVE COPPELL, TEXAS Summary of Classification and Index Property Tests Matdc Moisture Liquid Plastic Plasticity Soil Boring Depth Content Limit Limit Index Suction No. (feet) (%) (%) (%) (PI) (pst'). B-1 1.5 30 19.7 - - - 60,660 4.5 6.0 27.7 67 28 39 10,630 9.0 - 100 16.3 - - - 3,420 14.0 - 15.0 29.9 - - - 3,400 19.0 - 20.0 30.6 .... 5,690 24.0 - 25.0 27.5 .... 4,420 B-2 1.5 - 3.0 17.5 - - - 55,670 3.0 - 4.5 18.0 - - - 58,120 4.5 - 6.0 20.1 - - - 35,510 9.0 - 10.0 26.3 67 29 38 6,400 14.0 - 15.0 27.6 - - - 5,770 19.0 - 20.0 15.7 69 31 38 3,470 24.0 - 25.0 28.0 63 31 32 5,240 B-3 1.5 -3.0 13.2 ..... 161,730 4.5 -6.0 20.6 .... 18,360 9.0 -10.0 25.4 - - - 7,450 14.0 -15.0 22.5 - - - 6,160 19.0 -20.0 28.7 .... 3,110 24.0 - 25.0 29.8 - - - 5,920 29.0 - 30.0 29.7 - - - 3,620 B.-4 1.5 3.0 12.4 .... 272,770 3.0 4.5 14.6 62 22 40 165,960 4.5 6.0 19.1 - - - 56,750 9.0 - 10.0 26.3 - - - 3,800 14.0 - 15.0 25.2 - - - 4,610 19.0 - 20.0 24.6 - - - 3,780 24.0 - 25.0 30.2 - - - 3,830 S-OM'MARY OF I._~BORATORY TEST RES'0LTS 'PEA-'%E-~ ....... GEOTECHNICAL INVESTIGATION COPPELL TECH CENTER I! CRESTSIDE DRIVE AND LAKESHORE DRIVE COPPELL, TEXAS (Continued) Summary of Classification and Index Property Tests Matdc Moisture Liquid Plastic Plasticity Soil Bodng Depth Content Limit Limit Index Suction No. _( fe.e.tJ_ _( o/_~_ _(%) (%) (P I) (PS0 B-5 1.5 3.0 13.1 - - - 172,630 4.5 6.0 14.8 - - - 97,040 9.0 - 10.0 24.9 - - - 6,270 14.0 - 15.0 20.9 60 27 33 5,530 19.0 - 20.0 25.5 - - - 5,960 24.0 - 25.0 23.4 - - - 3,700 29.0 - 30.0 28.0 - - - 3,440 SUMMARY OF LABORATORY TEST RESULTS PLATE 10 Summary of Unconfined Compression Tests Dry Unconfined Moisture Unit Compressive Sample Bodng Depth Content Weight Strength legend No. (feet) (%) (pcf) (psf) A B-1 14.0 15.0 29.8 94.2 4830 B B-2 19.0 20.0 29.1 94.9 4450 C B-3 14.0 15.0 24.7 103.7 4470 D B-4 14.0 15.0 24.5 103.1 4500 E B-5 19.0 - 20.0 23.9 103.2 4860 ¢' ~,', .I?-.~/ · A ~ ~B ~ ~- ..' ~D 2 +E · ..- /j/?' 0 1 2 3 4 Strain (%) SUMMARY OF LABORATORY TEST RESULTS PLATE 11 Absorption Pressure Swell Test " Project No. 4814 Moisture Content (%) 28.2 31.9 Boring No. B-2 Penetrometer (tsf) 4.5++ 4.0 Depth (ft) 24-25 Dry Unit Weight (pcl) 90.5 89.4 Liquid Umit - Specific Gravity 2.65 2.65 Piasticit7 Index - Void Ratio 0.827 0.849 Cs 0.030 Saturation (%) 90 100 alpha 0.22 Spec. Volume 0.69 0.70 Percent Swell 1.2 Swell Pressure (PSO 1,300 250 · [ ~ 0.978 "'- ; ; . Ii' i J i ' ! ', ~' 0.928 ~ (:1,) · : -,!i- ' ' .0 (.,,0 4 : il-.t I .... n" - 0.878 > 0 ~ 0.828 100 1000 10000 100000 Restraining Swell Pressure (pst') 0.698 0.692 - 0.69 0.688 28 29 30 31 32 33 Moisture Content (%) ABSORPTION PRESSURE SWELL TEST PLATE 12 Absorption Pressure Swell Test Project No. 4814 Moisture Content (%) 25.7 32.3 Boring No. B-4 Peneb'ometer (ts0 3.75 1.25 Depth (ft) 19-20 Dry Unit Weight (PC0 98.0 91.2 Liquid Emit - Specific Gravity 2.76 2.78 Plasticity Index - Void Ratio 0.758 0.888 Cs 0.117 Saturation (%) 93 100 alpha 0.71 Spec. Volume 0.64 0.68 Percent Swell 7.4 Swell Pressure (psf) 3,240 250 " ', I "-' ~--,I J ' J !- 0.839 '.~ 0 · ~ i i · · 0.739 100 1000 10000 100000 Restraining Swell Pressure (ps~ 0.7 ~ 0.68 > 0.66 -- rd~ 0.64 I 0.§2 24 26 28 30 32 34 Moisture Content (%) ABSORPTION PRESSURE SWELL TEST PLATE 13 Absorption Pressure Swell Test Project No. 4814 Moisture Content (%) 22.7 25.9 Boring No. B-5 Penetrometer (tsf) 3,75 3.5 Depth (1~) 14-15 Dry Unit Weight (pc0 104.9 102.0 Liquid Umit - Specific Gravity 2.84 2.84 Plasticity Index - Void Ratio 0.690 0.737 Cs 0.046 Saturation (%) 93 100 alpha 0.52 Spec. Volume 0.60 0.61 Percent Swell 2.8 Swell Pressure (psf) 2,590 250 0.918 - .~1 ! ~i I ~ '----' ' ::' : ~ :: - 0.868 .._... -- : 'i I I~ , ~, o Ct) 4 ...... ,-:-? j,' ~ 0 · 0.768 100 1000 10000 100000 Restraining Swell Pressure (ps~ 0.615 ~) 0.61 ..... '~ o.605 .... o '~ 0.6 - /- : 0 595 0.59 22 23 24 25 26 27 Moisture Content (%) ABSORPTION PRESSURE SWELL TEST PLATE 14 Observation and Testing 1. Injection operations will be observed by a full-time representative of Reed Engineering Group, Inc. 2. Undisturbed soil samples will be obtained continuously throughout the injected depth, at a rate of one test hole per 10,000 square feet of injected area for confirmation. Sampling will be performed a minimum of 48 hours after the completion of the final injection pass. Project No. 4814/Report No. 1 - 3 - Water Injection Specifications September 25, 1998 w/Lime-Modified Cap GUIDELINE SPECIFICATIONS SOI~L MODIFICATION LIME AND WATER INJECTION FOR COPPELL TECH CENTER li CRESTS[DE DRIVE AND LAKESHORE DRIVE COPPELL, TEXAS Site Preparation Prior to the start of injection operations, the building pad should be brought to finished subgrade and staked out to accurately mark the areas to be injected. Allowance should be made for four to six inches of swelling that may occur as a result of the injection process. Materials 1. The lime slurry shall consist of potable water, hydrated lime and suffactant and shall be agitated as necessary to ensure uniformity of mixture. 2. Lime may be delivered to the jobsite as hydrated lime (calcium hydroxide) and mixed into a slurry or as calcium oxide and slaked on the jobsite to produce hydrated lime slurry. In either instance, the lime shall conform to the applicable parts of ASTM #C977. 3. A nonionic surfactant (wetting agent) shall be used according to manufacturer's recommendations, but in no case shall proportions be less than one part (undiluted) per 3,500 gallons water. Equipment I. The injection vehicle shall be capable of forcing injection pipes into soil with minimum lateral movement to prevent excessive blowback and loss of slurry around the injection pipes. The vehicle may be a rubber tire or trac machine suitable for the purpose intended 2. Slurry pumps shall be capable of pumping at least 3,000 GPH at 100 - 200 pounds per square inch (psi). 3. Slurry tanks shall have a suitable mechanical agitation system to insure proper mixing and uniformity of slurD'. Project No. 4814/Report No. 1 - I - Lime and Water Injection September 25, 1998 Specifications Application 1. The injection stabilization work shall be accomplished after the site has been brought to grade and prior to installation of any plumbing, utilities, ditches or foundations. 2. Adjust injection pressures within the range of 100 - 200 psi at the pump. 3. Mix slurry at the rate of 2-1/2 to 3 pounds lime per gallon of water which will produce a specific gravity of approximately 1.15 to 1.178 at 68°F (20°C). If quicklime is slaked, the specific gravity of the elevated temperature slurry must be adjusted to compensate for the decrease in density of water at slurry temperatures of 175° - 195OF using an appropriate conversion table. The injection contractor shall provide a hydrometer, Baroid Scale or other suitable method to accurately verif3, slurry, mixes. 4. Space injections not to exceed five feet on-center each way, and inject a minimum of five Feet outside building area Inject I0 feet beyond building at entrances. 5. Inject lime slurry to a depth of 10 feet, or impenetrable material, whichever occurs first. Impenetrable material is the maximum depth to which two injection rods can be mechanically pushed into the soil using an injection machine having a minimum gross weight of five tons. Injections to be made in 12-inch to 18-inch intervals down to the total depth with a minimum of seven stops or intervals. The lower portion of the injection pipes shall contain a hole pattern that will uniformly disperse the slurry in a 360° radial pattern. Inject at each interval to "refusal" (i.e., until the maximum quantity of slurry has been injected into the soil and slurry is running freely at the surface, either out of previous injection holes or from areas where the surface soils have fractured). Fluid coming up around or in the vicinity of one or more of the injection probes shall not be considered as soil refusal. If this occurs around any probe, this probe shall be cut off so that water can be properly injected through the remaining probes until refusal occurs for all probes. In any event, no probe shall be cut offwithin the first 30 seconds of injection after refusal at each depth interval. (The 30-second criteria is not the maximum time for each depth interval, but a minimum time. Additional time may be required to achieve refusal, dependent upon the contractor's equipment.) Project No. 4814/Report No. 1 - 2 - Lime and Water Injection September 25, 1998 Specifications 6. Following completion of all lime injection work specified alone, the entire area shall " be injected v,4th water and suffactant in the same manner and to the same total depth as specified for the lime injection. 7. Injections shall be made in approximately 12-inch to 18-inch intervals fi-om the surface down to the specified depth, injecting to refusal at each interval. 8. Multiple injections will be required. Injections shall be orthogonally offset fi-om pre,~4ous injections by 2-1/2 feet in each direction. Subsequent injections shall be such that existing probe holes are not utilized. 9. A minimum of 48 hours shall be allowed between the lime injection and subsequent water injection pass and between each water injection pass. 10. Injections will be continued until a pocket penetrometer reading of 3.0 tsf or less is obtained on undisturbed soil samples throughout the injected depth. This requirement can be waived by the engineer of record, if in his opinion, additional injections v,4il not result in additional swelling. 1 I. At the completion of injection operations, the surficial lime shall be mixed into the top four to six inches of soil and compacted to a minimum of 95 percent of maximum ASTM D-698 density, at or above optimum moisture. Observation and Testing 1. Injection operations will be observed by a full-time representative of Reed Engineering Group, Inc. 2. Undisturbed soil samples w411 be obtained continuously throughout the injected depth, at a rate of one test hole per 10,000 square feet of building area for confirmation. Sampling w411 be performed a minimum of 48 hours after the completion of the last injection pass. Project No. 4814/Report ~4o. 1 - 3 - Lime and Water Injection September 25, 1998 Specifications GUIDELENE SPECIFICATIONS SOIL MODHqCATION WATER INJECTION WP'SELF. Cr" FILL CAP FOR COPPELL TECH CENTER H CRESTSIDE DRIVE AND LAKESHORE DRIVE COPPELI,, TEXAS Site Preparation Prior to the start of injection operations, the building pad should be brought to finished subgrade, minus select fill, and staked out to accurately mark the areas to be injected. Allowance should be made for four to six inches of swelling that may occur as a result of the injection process Materials 1. Thc water shall be potable, with added surfactant, agitated as necessary to ensure uniformiw of mix-ture. 2. A nonionic surfactant (wetting agent) shall be used according to manufacturer's recommendations, but in no case shall proportions be less than one part (undiluted) per 3,500 gallons of water. Equipment 1. The injection vehicle shall be capable of forcing injection pipes into soil with minimum lateral movement to prevent excessive blowback and loss of slurry around the injection pipes. The vehicle may be a rubber tire or trac machine suitable for the purpose intended. 2. Slurry.' pumps shall be capable of pumping at least 3,000 GPH at 100 - 200 pounds per square inch (psi). Application 1. The injection work shall be accomplished after the building pad has been brought to finished subgrade, minus select fill, and prior to in~tallation of any plumbing, utilities, ditches or foundations. 2. Adjust injection pressures within the range of 100 - 200 psi at the pump. Project No. 4814/Report No. I 1 Water Injection Specifications September 25, 1998 wffSelect" Fill Cap 3. Space injections not to exceed five feet on center each way, and inject a minimum of five feet outside building area. Inject 10 feet beyond building at entrances.' 4. Inject to a depth of 10 feet or impenetrable material, whichever occurs first. Impenetrable material is the maximum depth to which two injection rods can be mechanically pushed into the soil using an injection machine having a minimum gross weight of five tons. Injections to be made in 12-inch to 18-inch intervals down to the total depth with a minimum of seven stops or intervals. The lower portion of the injection pipes shall contain a hole pattern that will uniformly disperse the slurry in a 360° radial pattern. Inject at each intel'al to "refusal". Refusal is reached when water is flowing freely at the surface, either out of pre,~4ous injection holes or from areas where the surface soils have fractured. Fluid coming up around or in the vicinity of one or more of the injection probes shall not be considered as soil refusal. If this occurs around any probe, this probe shall be cut off so that water can be properly injected through the remaining probes until refusal occurs for all probes. In any event, r:o probe shall be cut off within the first 30 seconds of injection at each depth interval. 5. Multiple injections with water and surfactant will be required. The second injection shall be orthogonally offset from the initial injection by 2-1/2 feet in each direction. Subsequent injections shall be offset such that existing probe holes are not utilized. 6. A minimum of 48 hours shall be allowed between each injection pass. 7. Injections vdll be continued until a pocket penetrometer reading of 3.0 tsf or less is obtained on undisturbed soil samples throughout the injected depth. This requirement can be wa/red by the engineer of record, if in his opinion, additional injections will not result in additional swelling. 8. At the completion of injection operations, the exposed surface shall be scarified and recompacted to a density of between 92 and 98 percent of maximum ASTM D-698 density, at or above optimum moisture. A minimum of 12 inches of select fill shall be placed over the injected subgrade as soon as is practical after completion of injection operations. Select fill should be placed in maximum loose Lifts of eight inches and compacted to at least 95 percent of maximum density, ASTM D-698, at a moisture content between -2 to +3 percentage points of optimum. Project No. 4814,rReport No. 1 - 2 - Water Injection Specifications September 25, 1998 w/"Select" Fill Cap Observation and Testing 1. Injection operations will be observed by a full-time representative of Reed Engineering Group, Inc. 2. Undisturbed soil samples will be obtained continuously throushout the injected depth, at a rate of one test hole per 10,000 square feet of injected area for confirmation. Sampling will be performed a minimum of 48 hours at, er the completion of the second injection pass. Project No. 4814/Report No. 1 - 3 - Water Injection Specifications September 25, 1998 wP'Select" Fill Cap