将杆系结构有限单元法与荷载传递迭代法相耦合。形成一桩基沉降分析计算的混合法.采用近似解析解中Ran—dolph and Worth’Model和双曲线模型相结合,模拟桩身与桩周介质边界上剪切滑移.桩间相互作用,采用弹性理论Mindlin方程解答计算,...将杆系结构有限单元法与荷载传递迭代法相耦合。形成一桩基沉降分析计算的混合法.采用近似解析解中Ran—dolph and Worth’Model和双曲线模型相结合,模拟桩身与桩周介质边界上剪切滑移.桩间相互作用,采用弹性理论Mindlin方程解答计算,并考虑了桩间“加筋与遮帘”作用.编制了群桩沉降分析计算程序GPSA1.通过计算分析,对刚性承台下群桩桩数、桩长、桩间距和桩土模量比等群桩工作特性的影响进行了系统研究.该方法和成果,可以作为今后群桩沉降分析研究的参考.展开更多
The pile group with elevated cap is widely used as foundation of offshore structures such as turbines, power transmission towers and bridge piers, and understanding its behavior under cyclic lateral loads induced by w...The pile group with elevated cap is widely used as foundation of offshore structures such as turbines, power transmission towers and bridge piers, and understanding its behavior under cyclic lateral loads induced by waves, tide water and winds, is of great importance to designing. A large-scale model test on 3×3 pile group with elevated cap subjected to cyclic lateral loads was performed in saturated silts. The preparation and implementation of the test is presented. Steel pipes with the outer diameter of 114 mm, thickness of 4.5 mm, and length of 6 m were employed as model piles. The pile group was cyclic loaded in a multi-stage sequence with the lateral displacement controlled. In addition, a single pile test was also conducted at the same site for comparison. The displacement of the pile cap, the internal forces of individual piles, and the horizontal stiffness of the pile group are presented and discussed in detail. The results indicate that the lateral cyclic loads have a greater impact on pile group than that on a single pile, and give rise to the significant plastic strain in the soil around piles. The lateral loads carried by each row of piles within the group would be redistributed with loading cycles. The lateral stiffness of the pile group decreases gradually with cycles and broadly presents three different degradation patterns in the test. Significant axial forces were measured out in some piles within the group, owing to the strong restraint provided by the cap, and finally lead to a large settlement of the pile group. These findings can be referred for foundation designing of offshore structures.展开更多
文摘将杆系结构有限单元法与荷载传递迭代法相耦合。形成一桩基沉降分析计算的混合法.采用近似解析解中Ran—dolph and Worth’Model和双曲线模型相结合,模拟桩身与桩周介质边界上剪切滑移.桩间相互作用,采用弹性理论Mindlin方程解答计算,并考虑了桩间“加筋与遮帘”作用.编制了群桩沉降分析计算程序GPSA1.通过计算分析,对刚性承台下群桩桩数、桩长、桩间距和桩土模量比等群桩工作特性的影响进行了系统研究.该方法和成果,可以作为今后群桩沉降分析研究的参考.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.51225804 and U1234204)the Zhejiang Electric Power Design Institute
文摘The pile group with elevated cap is widely used as foundation of offshore structures such as turbines, power transmission towers and bridge piers, and understanding its behavior under cyclic lateral loads induced by waves, tide water and winds, is of great importance to designing. A large-scale model test on 3×3 pile group with elevated cap subjected to cyclic lateral loads was performed in saturated silts. The preparation and implementation of the test is presented. Steel pipes with the outer diameter of 114 mm, thickness of 4.5 mm, and length of 6 m were employed as model piles. The pile group was cyclic loaded in a multi-stage sequence with the lateral displacement controlled. In addition, a single pile test was also conducted at the same site for comparison. The displacement of the pile cap, the internal forces of individual piles, and the horizontal stiffness of the pile group are presented and discussed in detail. The results indicate that the lateral cyclic loads have a greater impact on pile group than that on a single pile, and give rise to the significant plastic strain in the soil around piles. The lateral loads carried by each row of piles within the group would be redistributed with loading cycles. The lateral stiffness of the pile group decreases gradually with cycles and broadly presents three different degradation patterns in the test. Significant axial forces were measured out in some piles within the group, owing to the strong restraint provided by the cap, and finally lead to a large settlement of the pile group. These findings can be referred for foundation designing of offshore structures.
