Shear Stress Redistribution as a Mechanism to Mitigate the Risk of Liquefaction
Shear Stress Redistribution as a Mechanism to Mitigate the Risk of Liquefaction
复制标题
剪切应力重新分布作为减轻液化风险的机制
DOI：
10.1061/40975(318)115
复制
发表时间：
2008
期刊：
影响因子：
--
通讯作者：
K. Wissmann
中科院分区：
文献类型：
--
作者：
R. Green;C. Olgun;K. Wissmann
在松散、饱和的砂层中安装碎石桩或桥墩，通过将诱发的剪应力从砂土重新分布到桩或桥墩，从而减少对土壤的地震需求，从而潜在地减轻液化风险。在计算剪应力重分布时，通常假定土体和柱子或桥墩均为剪力梁。虽然不太常见，但也假设土体作为剪切梁响应，柱或桥墩作为弯曲梁响应，并相应地计算剪应力的重新分布。然而，本文的结果表明，柱或墩以及柱/墩周围的土体在剪切和弯曲的共同作用下发生变形。柱或墩的剪切变形对弯曲变形的贡献百分比随深度不同而不同，柱/墩的变形主要表现在地表附近的弯曲变形和深度的剪切变形上。每种变形模式的贡献百分比决定了剪应力从土体到桥墩的重新分布。土与柱子或桥墩之间的剪应力分布被量化为用ImpactTMRammed Aggregate PiersTM加固的松散饱和砂土剖面的“典型”特性。
The installation of stone columns or piers in a loose, saturated sand deposit can potentially mitigate the risk of liquefaction by decreasing the seismic demand on the soil by redistributing the induced shear stresses from the sand to the columns or piers. In calculating the shear stress redistribution, it is commonly assumed that both the soil and the columns or piers respond as shear beams. Although less common, it has also been assumed that the soil responds as a shear beam and that the columns or piers respond as flexural beams, with the redistribution of the shear stresses computed accordingly. However, the results presented herein show that the columns or piers, and the soil immediately surrounding the column/pier, deform in a combination of shear and flexure. The percent contribution of shear versus flexural deformation of the column or pier varies with depth, with the column/pier deforming predominantly in flexure near the ground surface and predominantly in shear at depth. The percent contribution of each mode of deformation governs the redistribution of the shear stresses from the soil to the pier. The distribution of the shear stresses between the soil and columns or piers are quantified for "typical" properties of a loose, saturated sand profile reinforced with ImpactTMRammed Aggregate PiersTM.