3D FE Analysis of Effect of Ground Subsidence and Piled Spacing on Ultimate Bearing Capacity of Piled Raft and Axial Force of Piles in Piled Raft
- 1 Department of Civil Engineering, Chulalongkorn University, Bangkok, Thailand
- 2 Department of Civil and Earth Resources Engineering, Kyoto University, Kyoto, Japan
- 3 Department of Civil Engineering, Chulalongkorn University, Bangkok, Thailand
Abstract
The effects of ground subsidence and piled spacing on axial force of piles in squared piled rafts were investigated using numerical analysis. Two cases of piled rafts in soft clay including case 1 (s = 2d) and case 2 (s = 4d) with s and d were piled spacing and piled diameter respectively were considered in this study. Undrained (without ground water pumping) and drained (with ground water pumping) conditions were applied in each case in order to evaluate variations of ultimate bearing capacity of piled raft and axial force of the piles in piled raft. The results showed that ultimate bearing capacity increased about 25% for undrained condition and about 32% for drained condition when piled spacing increased from 2d to 4d. In the same piled spacing, axial force of the piles increased about 9% for piled spacing of 2d and 7% for piled spacing of 4d when drained condition was applied. When piled spacing increased 2 times (2d to 4d), the axial force of piles increased about 7% for undrained condition and about 5% for drained condition.
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