Geomechanics and Engineering

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Effects of rock-support and inclined-layer conditions on load carrying behavior of piled rafts

  • Roh, Yanghoon (School of Civil and Environmental Engineering, Yonsei University) ;
  • Kim, Garam (School of Civil and Environmental Engineering, Yonsei University) ;
  • Kim, Incheol (School of Civil and Environmental Engineering, Yonsei University) ;
  • Lee, Junhwan (School of Civil and Environmental Engineering, Yonsei University)
  • Received : 2018.07.05
  • Accepted : 2019.06.15
  • Published : 2019.07.20
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Abstract

In this study, the load carrying behavior of piled rafts installed in inclined bearing rock layer was investigated for rock-mounted and -socketed conditions. It was found that settlements induced for an inclined bearing rock layer are larger than for a horizontal layer condition. The load capacity of piled rafts for the rock-mounted condition decreased as rock-layer inclination angle (${\theta}$) increased, while vice versa for the rock-socketed condition. The load capacities of raft and piles both decreased with increasing ${\theta}$ for the rock-mounted condition. When bearing rock layer was inclined, loads carried by uphill-side piles were greater than those by downhill-side piles. The values of differential settlements of rock-mounted and -socketed conditions were not significantly different whereas slightly higher for the rock-socketed condition. The values of load sharing ratio (${\alpha}_p$) and its variation with settlement were not markedly changed by the inclination of bedrock. It was shown that ${\alpha}_p$ for piled rafts installed in rock layer was not affected by ${\theta}$ whereas actual loads carried by raft and piles may vary depending on the pile installation and rock-layer inclination conditions.

Keywords

Acknowledgement

Supported by : Korea Institute of Energy Technology Evaluation and Planning (KETEP), National Research Foundation of Korea (NRF)

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