论文部分内容阅读
对于不同混杂配比的预应力高性能混杂纤维增强(HFRP)布,建立高性能HFRP布加固高性能混凝土(HPC)梁的双重非线性分层组合(DNLC)单元模型。根据实体退化单元理论,采用初应力等参层单元对高性能HFRP布的体外预应力效应进行模拟,同时正确地考虑HPC梁的材料非线性效应以及结构的几何非线性,验证DNLC单元分析模型的正确性,并对HPC梁的开裂荷载、普通钢筋应力、高性能HFRP布应力重分布等进行研究。结合试验资料分析表明,预应力碳/玻璃纤维混杂(CFRP/GFRP)布加固HPC梁的理论结果与试验数据吻合程度良好,采用等参层单元有效地模拟高性能HFRP布的预应力作用,及所推导的DNLC单元正确性。预应力GFRP纤维布加固的开裂荷载等均较低,预应力CFRP纤维布加固的开裂荷载等有所提高,但剩余强度过大。HPC梁开裂荷载前预应力高性能HFRP布应力发展缓慢,屈服荷载后,其发展迅速直至结构失效。
For the different mixed ratio of prestressed high performance hybrid fiber reinforced (HFRP) fabrics, a double nonlinear layered combination (DNLC) unit model of high performance HFRP sheet reinforced high performance concrete (HPC) beams was established. According to the theory of solid degenerate element, the prestressing layer element is used to simulate the external prestressing effect of high-performance HFRP fabric. Meanwhile, the material non-linear effect of HPC beam and the geometric nonlinearity of the structure are considered correctly. Correctness, crack load of HPC beam, stress of common rebar, stress redistribution of high-performance HFRP cloth and so on were studied. The experimental results show that the theoretical results of prestressed carbon / glass fiber hybrid (CFRP / GFRP) reinforced HPC beams are in good agreement with the experimental data. The isoparametric elements effectively simulate the prestressing effect of high performance HFRP fabrics and Derived DNLC unit correctness. The cracking load of prestressed GFRP fiber cloth is lower and the cracking load strengthened by prestressed CFRP fiber cloth is improved, but the residual strength is too large. The prestressing high-performance HFRP fabric has a slow development of stress before the cracked HPC beam. After the yield load, the stress develops rapidly until the structural failure occurs.