基于Ansys体外无粘结预应力筋加固铁路盖板涵静载分析

目前大秦铁路运输荷载日趋增加,原有盖板的各种病害日益突出,为了改善大秦重载铁路盖板掉块,钢筋锈蚀等病害,提高盖板的承载能力,对盖板进行了体外无粘结预应力筋加固试验研究。根据已加固盖板涵的室内静载试验和有限元模型,结合数据研究了无粘结预应力筋的加固效果。结果表明,无粘结预应力筋加固可以明显提高盖板的承载能力,在正常使用状态混凝土压应力最大降低约35%。最后,借助力学理论推导了无粘结预应力筋应力增量计算公式,根据试验结果验证了理论计算的准确性,为无粘结预应力筋加固的实际施工提供理论指导。

Ansys-based Static Load Analysis of Railway Culvert with External Unbonded Pre-stressed Reinforcement

With the increasing Da ~ Qinrailway transport load,the defects of original cover have become increasingly prominent. To improve the bearing capacity of Datong-Qinhuangdao railway culvert covers by preventing them from block-dropping and steel corrosion,this paper focuses on the external unbonded pre-stressed reinforcement to dress the issue. Based on the indoor static test of reinforced culver cover and finite element model,this paper studies the effect of unbonded pre-stressed reinforcement. The results show that the unbonded pre-stressed reinforcement can improve remarkably the bearing capacity of cover,and the concrete compressive stress is reduced about 35% in normal use. Finally,with the mechanical theory,the calculation formula of stress increment of external tendons is deduced,the accuracy of theoretical calculation if verified by the test results, which provide theoretical guidance for the construction of external pre-stressed reinforcement.