<p><p><figure id='attachment_3390' style='max-width:956px' class='caption alignnone'><img class="wp-image-3390 size-full" src="https://www.geoinstitute.org/sites/default/files/geotech-tools-uploads/…; alt="Photograph sowing Test pile and production pile installation in Sorting/Truck Facility, North Carolina." width="956" height="730" /><figcaption class='caption-text'> Test pile and production pile installation (Lacz et al. 2009).</figcaption></figure></p><p><h2>Project Summary/Scope:</h2>A package sorting/truck facility was constructed in Greensboro, NC. The facility was supported on 821 CFA piles, with lengths from 14.6 meters (48 feet) to 23.6 meters (77.5 feet) below grade. The building footprint is 28,465 square meters (306,400 square feet) in plan area, with maximum building dimensions of approximately 155.4 meters (510 feet) by 192.0 meters (630 feet), and a height of 18.3 meters (60 feet). Several pile locations encountered large shot rock fragments that required excavation.</p><p>Subsurface Conditions: The site is located in the Carolina Slate Belt. The parent bedrock underlying the facility is a well-foliated metamorphosed granitic parent bedrock. The on-site residual soils are the product of in-place weathering of the parent bedrock. The subsurface conditions at the site generally consisted of soil fill, alluvium, residual soils, and partially weathered rock. The groundwater table depth varied from 4.6 to 13.6 meters (15 to 45 feet) across the site.</p><p>Maximum column loads were estimated at 4,110 kN (925 kips) in compression, 670 kN (150 kips) in uplift, and 200 kN (45 kips) in shear during the design phase. Floor loading was anticipated to be moderate to heavy, with floor loads of approximately 24 kPa (500 psf). The diameter of the CFA piles was 16 inches. To reduce settlement, the area of the building was preloaded using a minimum surcharge pressure of 38 kPa (800 psf).</p><p>The 821 CFA piles were installed from October 25, 2006 to December 4, 2006.<br><h2>Performance Monitoring:</h2>Automated Monitoring Equipment (AME) was used during construction. The project used the PIR-A pile installation recorder, manufactured by Pile Dynamics, Inc. Components of the AME included a display unit, depth sensor, magnetic flow meter, grout pressure sensor, field printer, torque pressure sensor, and angle analyzer. The parameters measured included time, depth, and hydraulic pressure during drilling, as well as time, depth, grout volume, and grout pressure during grouting. Conventional auger cast pile observations were performed including shaft diameter, drilling procedures, eccentricity, plumbness, bearing materials, grout usage, and grout procedures. Two static load tests and three tension load tests were also performed. The compression load tests were performed according to ASTM D1143. The tension piles were tested according to ASTM D-3689.<br><h2>Project Technical Paper:</h2>Lacz, S.W. and Wells, R.C. (2009). “Design, testing and automated monitoring of ACIP piles in residual soils.” Contemporary Topics in Deep Foundations, GSP No. 185, ASCE, Orlando, FL, pp. 414-421. <a href="http://ascelibrary.org/doi/abs/10.1061/41021%28335%2952">http://ascelib… Case History Prepared:</h2>November 2012</p></p>