盖板体外预应力加固的应力增量统一算法

A Unified Algorithm for Calculating Stress Increment of Externally Prestressed Slab Culvert

基于体外预应力筋应力增量与梁体跨中挠度及混凝土压应变的相关性,提出了盖板体外预应力筋加固的结构计算模型.利用结构变形前后的几何关系,导出了体外预应力筋应力增量的统一表达式,并用室内模型试验证明计算方法的准确性.同时分析了影响体外筋应力增量的力筋面积、预应力值、外荷载形式及既有梁配筋率等参数的敏感性,可为实际工程提供理论支持.

Based on the pertinence of the external tendons stress increment,the calculation model of linear type external prestressing slab culvert is proposed.By using the geometrical relationship before and after deformation,a unified expression for external tendons stress increment is solved.The accuracy of the method is demonstrated by a laboratory model test.And the sensitivity analysis is performed to study the parameters,such as area of external tendons,effective prestress,load form and reinforcement ratio,thus to provide good technical support for practical engineering reinforcement.