To evaluate the responses of fixed and pinned pile groups under torsion, a method is presented to analyze the nonlinear behavior of free-standing pile groups with rigid pile caps. The method is capable of simulating t...To evaluate the responses of fixed and pinned pile groups under torsion, a method is presented to analyze the nonlinear behavior of free-standing pile groups with rigid pile caps. The method is capable of simulating the nonlinear soil response in the near field using p-y and τ-θ curves, the far-field interactions through Mindlin's and Randolph's elastic solutions, and the coupling effect of lateral resistance on torsional resistance of the individual piles using an empirical factor. Based on comparisons of the solutions for fixed-and pinned-head, 1×2, 2×2, and 3×3 pile groups subjected to torsion, it was found that pile-cap connection significantly influences the torsional capacity of pile groups and the assignment of applied torques in the pile groups. In this study, the applied torques for the pinned-head pile groups are only 44%～64% of those for the corresponding fixed-head pile groups at a twist angle of 2°. Such a difference is mainly due to the change of the lateral resistances of individual piles in the groups.展开更多
Rectangular-closed-diaphragm-wall foundation is a new type of bridge foundation.Diaphragm wallsoil-cap interaction was studied using a model test.It was observed that the distribution of soil resistance under the cap ...Rectangular-closed-diaphragm-wall foundation is a new type of bridge foundation.Diaphragm wallsoil-cap interaction was studied using a model test.It was observed that the distribution of soil resistance under the cap is not homogeneous.The soil resistance in the corner under the cap is larger than that in the border;and that in the center is the smallest.The distribution of soil resistance under the cap will be more uniform,if the sectional area of soil core is enlarged within a certain range.Due to the existence of cap,there is a“weakening effect”in inner shaft resistance of the upper wall segments,and there is“enhancement effect”in the lower wall segments and in toe resistance.The load shearing percentage of soil resistance under the cap is 10%–20%.It is unreasonable to ignore the effects of the cap and the soil resistance under the cap in bearing capacity calculations.展开更多
基金Project (No. HKUST 6037/01E) supported by the Research GrantsCouncil of Hong Kong SAR, China
文摘To evaluate the responses of fixed and pinned pile groups under torsion, a method is presented to analyze the nonlinear behavior of free-standing pile groups with rigid pile caps. The method is capable of simulating the nonlinear soil response in the near field using p-y and τ-θ curves, the far-field interactions through Mindlin's and Randolph's elastic solutions, and the coupling effect of lateral resistance on torsional resistance of the individual piles using an empirical factor. Based on comparisons of the solutions for fixed-and pinned-head, 1×2, 2×2, and 3×3 pile groups subjected to torsion, it was found that pile-cap connection significantly influences the torsional capacity of pile groups and the assignment of applied torques in the pile groups. In this study, the applied torques for the pinned-head pile groups are only 44%～64% of those for the corresponding fixed-head pile groups at a twist angle of 2°. Such a difference is mainly due to the change of the lateral resistances of individual piles in the groups.
基金supported by the National Basic Research program(2008CB425801)。
文摘Rectangular-closed-diaphragm-wall foundation is a new type of bridge foundation.Diaphragm wallsoil-cap interaction was studied using a model test.It was observed that the distribution of soil resistance under the cap is not homogeneous.The soil resistance in the corner under the cap is larger than that in the border;and that in the center is the smallest.The distribution of soil resistance under the cap will be more uniform,if the sectional area of soil core is enlarged within a certain range.Due to the existence of cap,there is a“weakening effect”in inner shaft resistance of the upper wall segments,and there is“enhancement effect”in the lower wall segments and in toe resistance.The load shearing percentage of soil resistance under the cap is 10%–20%.It is unreasonable to ignore the effects of the cap and the soil resistance under the cap in bearing capacity calculations.
