两桩承台拉压杆模型的构形方法及关键参数取值研究

Strut-and-tie Models for Two-pile Caps:Configuration and Parameter Selection

研究了两桩承台在3种典型受力工况下的拉压杆模型设计方法,分别对应于桥墩处于轴压、小偏压和大偏压的情形。给出了不同工况下拉压杆模型的定量化几何构形;研究并确定了拉压杆模型中的节点几何形状和尺寸、混凝土有效强度等关键参数的取值方法;最后,通过实例计算演示了应用拉压杆模型进行承台验算的一般流程,结果表明本文方法具有较好的可操作性和适用性。

In this paper, strut-and-tie models （STMs） for two-pile caps were established for three different typical load cases , which include piers under axial compression , small eccentric compression and large eccen-tric compression.Firstly, shape configurations of STMs in different load cases were studied .After that, geom-etries and dimensions of nodes and effective concrete strengths in STMs were investigated .Finally, the general procedure for pile-cap strength checking was illustrated through a working example , which shows that the pro-posed method is practical and applicable .