体外预应力连续梁的受力性能研究与非线性分析

通过试验分析了体外预应力梁在整个加载过程中的反应。如 :预应力筋材料的非线性本构关系 ,体外预应力筋偏心距的变化 ,在转向块处预应力筋受摩擦的影响等。同时利用条带法编制了有限元非线性分析程序EPRCS ,在单元刚度矩阵中 ,考虑了材料非线性与几何非线性 ,轴力二次矩等。计算结果与试验结果对比表明 ,采用的计算模型符合实际受力状态 ,所使用的在转向块处预应力筋摩擦的模型能很好地反映预应力筋在实际受力过程中的状态。

RESEARCH ON STRESSING PROPERTIES OF CONTINUOUS EXTERNALLY PRESTRESSED BEAMS AND NONLINEAR ANALYSIS

The behavior of the externally prestressed concrete beams during the entire process of loading is analyzed through the tests.The influencing factors,such as the nonlinear constitutive relation of the prestressed reinforcement material,a change in the eccentricity of the externally prestressed reinforcement and the effect of the friction on the reinforcement at the steering block etc,are taken into account.The strip method is used for making a nonlinear finite element analysis program EPRCS.The material nonlinearity,geometrical nonlinearity and the axial second order moment are also taken into consideration in the element stiffness matrix.It is indicated by contrasting the calculated results to those of the tests that the behavior by the calculation model is in accord with the actual stressing state;and the frictional model of the prestressed reinforcement at the steering block can well reflect the actual behavior of the prestressed reinforcement during stressing.