DFI-PFSF Piled Foundations & Ground Improvement Technology for the Modern Building and Infrastructure Sector, (DFI and PFSF)
Performance of Large-Diameter Bored Pile Socketed in Sandstone and Siltstone in Thailand
Zaw Zaw Aye, Thayanan Boonyarak, Nutthapon Thasnanipan and Sereyroath Chea
As there are only limited numbers of bored pile constructed in sandstone and siltstone in Thailand, load transfer and settlement behavior of a pile in these rocks are still not fully understood. Major factors which influence the performance of the pile in the sedimentary rock should be systematically investigated. The objective of this paper is to analyze load distribution and load-settlement behavior of bored pile in sedimentary rock. Interpreted data was obtained from instrumented load testing results of large-diameter bored piles. These piles were drilled in aeolian soil and socketed in sandstone or siltstone, having socketed length varying from 1 to 3 times the pile diameter. Factors that influenced pile settlement behavior, consisting of rock type at the pile base, socket length, at-rest earth pressure and rock conditions, were analyzed. For interpretation of results, analytical solutions were used to estimate load bearing capacity and calculate settlement of each pile. According to test results of mobilized unit skin friction in siltstone, relationship of 0.1 – 0.3 square root of the unconfined compressive strength of rock appears to reasonably capture the measured shaft friction. Note that shaft movement in siltstone layer was not fully mobilized as maximum pile head settlement was still less that 1% of the pile diameter.
|article #2581; publication #1032 (IC-2017)|