软土地基邻近堆载对桥梁桩基偏位的影响研究

在软土地基中，邻近堆载不仅将引发桥梁桩基发生侧向偏位，还将导致桩身产生附加弯矩，这对于桥梁的安全使用将产生极其不利的影响。通过对具体工程实例的介绍，利用有限元分析手段，并结合现场桩基偏位的实测结果，对邻近单侧堆载及双侧堆载所引发桩基偏位情况进行深入剖析。通过分析结果可知，在单侧堆载的作用下，桩基将产生侧向偏移及附加弯矩，且反弯点位于软土层与硬土层交界处附近，严重时将导致桩顶区域发生开裂破坏；在双侧堆载的作用下，桩基的偏位情况取决于两侧的堆载作用，而双侧卸载对桩基偏位影响较小，但对缓解桩身附加弯矩具有显著的作用。

Study of influence of surcharge load on lateral displacement of bridge piled foundation in soft ground

In soft ground, the lateral displacement of piled foundation and the additional bending moment of the bridge pile caused by the surcharge load is an extremely negative impact on the safety of the bridge. Through the introduction of specific project, the influences of the unilateral and bilateral surcharge load on the lateral displacement and the internal force of the bridge piled foundation are analyzed in-depth using the finite element analysis; and the calculation results and the measured results are compared. According to above analyses, the change rules of the lateral displacement and the internal force of the bridge piled foundation are further understood. By the impact of unilateral surcharge, the lateral offset and bending moment on the pile is much more significant. The inflection point of the pile is occurred at the interface between the soft soil and hard soil. While the additional bending moment of the pile is significant, it will result in pile cracking. By the impact of bilateral surcharge, the lateral offset of the piled foundation is determined by both sides of the load. Unloading both sides at the same time is less impact on the lateral offset of the piled foundation; but it plays an important role in reducing additional moment of the pile.