基于体外钢束-混凝土协作关系的体外钢束应力增量分析方法

Stress Increment Analysis of the External Prestressing Cables Based on Coordinating Relations Between External Prestressing Cables And Concrete

提出了基于体外钢束-混凝土协作关系的体外钢束应力增量分析方法.针对典型断面构件中相互独立的体外钢束与混凝土一起工作所需满足的关系,推导了钢混协同工作的主从关系式.这种关系可由非线性有限元的求解过程自动实现,即在进行不平衡力的迭代时,引入预应力钢索与混凝土的变形协调关系,进而可求出体外束随结构变形而产生的伸长量及应力增量.算例表明,所提出的方法可有效地分析体外束应力增量、模拟体外索预应力桥梁的结构行为.

In order to find out a method with high precision and fitness for calculation on external prestressing stress increment, the paper has proposed a stress increment analysis method based on coordinating relations between the external prestressing cables and concrete. Aiming at the co-work condition of the independent external prestressing cables and concrete in a typical component section, the coordinating relations between them are induced. The relations can be carried out automatically during the process of solution of the nonlinear equations. In this way, it is convenient to acquire the elongations and the stress increments in any load step. The engineering example shows that the method that developed in this paper is effective to analyze the external prestressing stress increments and simulate the structural behaviors of externally prestressed bridges.