Pile ID TP-1 TP-2 TP-3 TP-4 Pile Type PSC SCPTC SCPTC SCPTC Pile width / diameter in (mm) 30 (762) 66 (1676) 66 (1676) 66 (1676) Test pile (TP) information samples were extracted at different depths for comprehensive laboratory testing. The laboratory testing program included moisture content, Atterberg limits and unconsolidated undrained (UU) triaxial tests. The in-situ testing program included performing cone penetration tests (CPT) and standard penetration tests (SPT) near the TP locations. The CPT provided measurements of cone tip resistance (q ) c and sleeve friction (f ). The profile of CPT s tests was used to classify the soil using the Zhang and Tumay (1999) probabilistic region estimation method. The subsurface soil stratigraphy at each of the TP locations primarily consisted of clay with inter- mittent sand layers. Pile Instrumentation and Installation: The TPs were instrumented with 3 to 6 strain gauge pairs to evaluate the load distribution along the length of the piles and to determine the side and tip resis- tances, separately. TP-1 was driven with a Conmaco 300 E5 pile driving hammer. The LDOE cylinder piles (i.e., TP-2, TP-3 and TP-4) were driven using a Bruce SGH-3013 hydraulic hammer. The SGH-3013 has a rated hammer energy of 282.1 kip-ft with a ram weight of 66 kips (294 kN) and a maximum stroke height of 4.3 ft (1.3 m). Plugging was not measured in this project due to the construction constraints. Load Testing Program The load testing program was designed to confirm the pile resistance, study the pile setup behavior and assess drivability. An extensive load testing program was carried out after pile installation using a SLT, DLTs, and SNLTs at this construction site. The SLT was performed only on the PSC TP (i.e., TP-1). It was decided that multiple restrikes and one SNLT would be used to 82 • DEEP FOUNDATIONS • SEPT/OCT 2019 Soil profile, CPT profile and classification at TP-2 Total length ft. (m) 57 (17.4) 153 (46.6) 183 (55.8) 176 (53.6) Penetration length ft (m) 41.5 (12.6) 119.8 (36.5) 174.9 (53.3) 164.3 (50.1) Pile Hammer Conmaco 300 E5 Bruce SGH-3013 hyd. Bruce SGH-3013 hyd. Bruce SGH-3013 hyd. Pairs of Strain Gauges 5 3 6 5 Strain Gauge Depth, below ground ft (m) 0, 13.5, 24, 34, 44.5 (0, 4.1, 7.3, 10.4, 13.6) 0, 56, 88.5 (0, 17.1, 27.0) 0, 51, 82.5, 114, 147, 173.5 (0, 15.5, 25.1, 34.7, 44.8, 52.9) 0, 3, 51.5, 84, 116, 148 (0, 0.9, 15.7, 25.6, 35.4, 45.1) Note: PSC = prestressed concrete pile; SCPTC = spun cast post-tensioned cylindrical pile (LDOE) Driving resistance and CAPWAP analyses of test piles
