<p>A piled-raft foundation (PRF) allows carrying higher superstructure loads with restrained settlements. This paper highlights the importance of adopting bored piles over driven piles in supporting a PRF in a compressible ground with the aid of a case study related to an infrastructure development at IIT Guwahati campus. Based on two-dimensional finite element analyses, a comparative is presented to elucidate the detrimental implications of adopting driven piles for PRFs resting on soft compressible medium with water table near the ground surface. It is successfully perceived that dynamic loading applied on driven piles lead to substantial generation or pore pressure that take long time to dissipate from the low-permeable soils, thereby inflicting long-term distresses in the PRF system. Further, with the aid of the case study, the response of a PRF supported by bored cast-in-situ piles are exhibited and the influences of various pile and raft entities are manifested. The sharing of the applied load by the pile and the raft are manifested through ‘load sharing ratio’ that is computed from the outcomes of the finite element analysis. It is observed that the pile of larger lengths and diameters with those located at closer spacing to each other are more effective in accommodating the major share of the externally applied load, thereby exhibiting larger load sharing ratios.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

Behavior of piled-raft foundation (PRF) in compressible ground: A case study delineating the importance of adopting bored piles over driven piles

  • Arindam Dey,
  • Milind Patil,
  • Kandukuri Shanker

摘要

A piled-raft foundation (PRF) allows carrying higher superstructure loads with restrained settlements. This paper highlights the importance of adopting bored piles over driven piles in supporting a PRF in a compressible ground with the aid of a case study related to an infrastructure development at IIT Guwahati campus. Based on two-dimensional finite element analyses, a comparative is presented to elucidate the detrimental implications of adopting driven piles for PRFs resting on soft compressible medium with water table near the ground surface. It is successfully perceived that dynamic loading applied on driven piles lead to substantial generation or pore pressure that take long time to dissipate from the low-permeable soils, thereby inflicting long-term distresses in the PRF system. Further, with the aid of the case study, the response of a PRF supported by bored cast-in-situ piles are exhibited and the influences of various pile and raft entities are manifested. The sharing of the applied load by the pile and the raft are manifested through ‘load sharing ratio’ that is computed from the outcomes of the finite element analysis. It is observed that the pile of larger lengths and diameters with those located at closer spacing to each other are more effective in accommodating the major share of the externally applied load, thereby exhibiting larger load sharing ratios.