无粘结预应力粉煤灰混凝土桥梁极限承载力的有限元分析

Analysis of nonlinear finite element on ultimate bearing capacity of unbonded prestressed high performance fly ash concrete beam

根据有限元理论及基本假定,考虑了材料的非线性及结构的几何非线性,应用Fortran语言编制无粘结预应力高性能粉煤灰混凝土桥梁极限承载力的非线性有限元程序,并用程序对9根无粘结预应力混凝土试验梁进行了计算.计算结果和试验结果符合良好,说明该分析程序是可靠的,并且能准确可靠的预测无粘结预应力高性能粉煤灰混凝土桥梁从开始加载直到破坏的全过程结构响应;试验结果也表明不同粉煤灰掺量对高性能混凝土桥梁的极限承载力影响不大和高性能粉煤灰混凝土桥梁中混凝土、钢筋和预应力钢筋参数按《桥规》取值计算能够取得比较满意的结果.

According to nonlinear finite element theory and basic assumption,considering both material and geometrical nonlinearity,Fortran language was used to compile nonlinear finite element analysis program ,which was utilized to compute nine unbonded prestressed concrete test beams,about the ultimate bearing capacity of unbonded prestressed high performance fly ash concrete beams.The result of computation broadly accord with that of the test,so the analysis program was reliable,besides,it accurately and reliably forecast the whole process of structural response from load to damage about unbonded prestressed high performance fly ash concrete beams. Meanwhile the result of test shows that the differences of fly-ash contents and intensity of concrete hardly have an effect on intensity of high-performance concrete,and it also indicates that the parameters of concrete,steel and reinforce steel referring to General Code for Design of Highway Bridges and Culverts,eventually,achieve satisfactory results in the course of computation.