考虑液化场地效应的地下结构侧向变形研究

针对液化场地侧向变形对地下结构的作用效应，建立土-地下结构体系的简化力学模型。考虑地下结构的非线性变形效应，地下结构弯曲变形效应采用三折线模型，土-地下结构的相互作用采用理想弹塑性模型，由此得出液化场地中地下结构侧向变形的解析解，并通过规范提出的反应位移法对解析解进行验证，证明了解析解的可靠性和有效性。结果表明：当Ug较小时，解析解与反应位移法计算得出的结果吻合程度较好；当Ug较大时，解析解与反应位移法结果沿深度的变化趋势一致，但解析解大于反应位移法的计算结果。不同上覆土层厚度对地下结构的影响不同，地下结构的弯矩在液化层与非液化层的交界面附近达到最大，并且其位置随着上覆层厚度的增加逐渐下移。

Lateral deformation of underground structure based on effect of liquefaction site

A simplified mechanics model of soil-underground structure system is established for the effect of lateral deformation of underground structure. Considering the non-linear deformation effect of underground structure, the three-fold line model is adopted to simulate the deformation of underground structure, and the ideal elastic-plastic model applies for the interaction between soil and underground structure. Based on the two models, the analytical solution of lateral deformation of underground structures in liquefied site is obtained. And the analytical solution is verified by the response displacement method, which proves its reliability and validity. The result shows that the analytical solution and the results calculated by the response displacement method are consistent when Ug is not large enough. However, with Ug get larger, the analytical solution and the response displacement results are consistent with the change of depth, but the analytical solution is larger than that of the response displacement method. In addition, the influence induced by different thickness of overlaying soil on underground structure is different. The bending moment of underground structure reaches the maximum near the interface between liquefied layer and non-liquefied one, and its position gradually decreases with the increase of embedded soil depth.