doi:10.3850/9789628014194_0012

ABSTRACT

The piled-raft foundation is a type of economical foundation where the raft, piles and soil work together to bear vertical load. In design, the key issue is how to reduce differential settlements on the raft. Three dimensional elasto-plastic numerical simulation for a test model of piled-raft foundation with equilong piles in a high-rise building is carried out in this paper to determine the effect of raft thickness, pile diameter and length, different pile arrangements on settlements and moments on the raft. According to the analytical results, the new concept of area stiffness is proposed to characterize the mutual bearing mechanism among raft, pile and soil . If the slope coefficient K_AS of the trendline for area stiffness distribution is equal to 10⁶kN/m, the differential settlement on the raft is found to be minimal.

Keywords: Area stiffness, Differential settlement, Piled-raft foundation.

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