Abstract:

An analysis method of piled raft foundation with rigid cap is presented with the research results about allocation rhythm of side resistance in pile group. Based on displacement compatibility relationship, pile body stress and strain equation and force equilibrium relationship, stiffness matrix which relate top force to displacement is deduced. Four types of intreraction is considered herein, that is pile-soil-pile interaction, pile-soil-plate interaction, plate-soil-pile interaction and plate-soil-plate interaction. It is mentioned that pile group can be comprised of piles with the property of various lengths, radii and stiffnesses. The method does not involve the discretization of the soil or piles and it follows the same analysis process and the content of stiffness matrix is just related to the number of pile and soil nodes under foundation cap. Comparison with the results of other analysis methods shows that the method is feasible and accurate.

Key words: piled raft foundation, rigid cap, displacement, side resistance force