高性能多功能桥墩永久模板节段节点性能分析

摘要

为了给高性能多功能桥墩永久模板节段节点设计提供科学依据,根据超高性能水泥基复合材料( UHPCC)纵向节段间的节点联接构造,分析了界面应力,建立了切向应力和法向应力分量的表达,提出了界面联接率的设计参量,并给出了焊缝节点应力极限状态方程.基于荷载规范,给出了永久模板的施工荷载计算参量表达.简要介绍了UHPCC的基本性能、计算模型,提出了将UHPCC应用于桥墩用多功能永久模板的设计概念,并结合典型墩柱结构进行了UHPCC管界面节点性能的计算,分析了壁厚、焊缝有效厚度等设计参量对节点性能的影响规律,分析了界面联接参量对焊缝应力的影响规律,提出了UHPCC管连接节点的设计方案.该研究为UHPCC永久模板管结构节段节点强度设计奠定了基础.%In order to propose trre scientific basis for the segmental joint design of the high performance and multifunctional permanent form work of a pier, the interfacial stress was analyzed according to the segmental joint structure of longitudinal sections of ultra high performance cementitious composites (UHPCC), and the expressions of tangential stress and normal stress were given, the design parameters of interface connection rate was proposed, and the ultimate state equation of the weld joint stress was given. Based on the construction load code, the calculating parameter expressions of construction loads for the UHPCC thin circular tube were presented. The basic properties and calculating constitutive model of UHPCC were introduced. The design concept of applying UHPCC into multifunctional permanent form work for bridge piers was presented in this paper. With geometrical dimensions of a typical pier, the interfacial joint performance parameters of a UHPCC tube under typical construction loads were calculated. The effect of the geometrical parameters such as wall thickness and effective thickness of a weld joint on the joint performance, as well as the effect of the interface connection parameters on the weld stress, was analyzed. A design scheme for the UHPCC tube connection joints was proposed. This study lays a basis for the segmental joint strength design of the permanent form work of a UHPCC tube.