后张预应力混凝土空心板梁端裂缝分析及试验研究

Beam End Cracks Analysis and Test Study of Post-tension Prestressed Concrete Hollow Slab

为了精确分析后张法预应力混凝土空心板梁,在预应力的作用下梁端横向应力过大产生开裂的现象,考虑到由于后张法梁端开裂分析研究较为复杂,采用平面杆系理论进行桥梁整体分析,同时进行梁端局部实体计算,通过实体分析证明了横向分析的重要性,得出各种裂缝的成因.同时,根据梁的实际情况给出了裸梁加载的计算方法,现场实测了板梁内力、挠度与裂缝发展情况等参数.依据理论和试验研究的结果,给出了板梁的维修、加固方案,保证了结构的安全使用.

In order to analyze the feature of post-tension prestressed concrete hollow slab accurately and find the reasons of the beam end cracks under the prestressed force which causes huge transverse stresses, the plane bar member theory is adopted for the whole analysis of the bridge, and the solid calculation is done on the beam end local, for the analysis of beam end cracks of post-tension prestressed beams is com- plicated. The importance of transverse analysis is proved according to the solid study, and the reasons of all kinds of cracks are obtained. At the same time, the naked beam loading calculating methods are given according to the reality. The internal force, deflection and cracks of the slab beams are measured in spot. The repairing and reinforced projects are given according to the results of theory and test study to ensure the safety use of the stucture.