预应力高强混凝土箱梁极限承载力研究

Study on ultimate bearing capacity for the pre-stressed high strength concrete box girder

用C70的预应力高强混凝土箱梁进行了足尺破坏试验,研究其受力全过程。分析了从初始加载至弯曲破坏的荷载位移曲线。建立了有限元模型,同时参照规范中相应公式计算梁的开裂弯矩和破坏弯矩,两者与试验数据进行对比,结果较一致。研究结果表明:单梁的开裂弯矩与规范算法、有限元模型计算结果三者吻合较好,三者的两两比值为0.99~1.02。此外,采用有限条代法计算所得破坏弯矩与试验结果也吻合较好。

Taking C70 prestressed high strength concrete box girder as the object of the study,full-scale failure test was carried out and the whole stress process was analyzed.The load displacement curve from initial load to flexural failure was analyzed.The finite element software was used to establish the model,and the corresponding calculated formula from standard was used to analyze the cracking and destruction moment.The two calculated results were consistent with the experimental data.The results showed that the cracking moment of single beam was calculated with the standard algorithm and the finite element model.The three results were in good agreement with each other that the ratio of the 3 databases ranged from 0.99 to 1.02.Moreover,the calculated destruction moment according to strip methods also had better tally with experimental results.