横向预应力对装配整体式空心板桥纵向抗裂性能的影响

装配式空心板梁桥普遍应用于中小型公路桥梁中,但其容易在竖向梯度温度的作用下产生铰缝开裂。针对这一现象,提出了横向预应力预压抗裂的方法。利用ABAQUS有限元软件建立装配式空心板桥梁实体模型,分析装配式空心板桥梁的开裂成因,研究横向预应力对装配式空心板桥梁抗裂性能的影响。结果表明:竖向梯度温度作用下,空心板桥梁铰缝截面产生极大的拉应力,是导致铰缝初期开裂的重要因素;对空心板桥梁施加横向预应力能有效的消除铰缝处由于温度作用效应所产生的拉应力,使铰缝处于受压状态,提高铰缝的抗裂性能。研究所得结论能为解决装配式空心板桥梁铰缝病害提供借鉴。

Impacts of Transverse Prestress on Cracking Resistance of Assembly Type Hollow Slab Bridge

Assembly hollow slab bridge has been commonly adopted in middle and small span highway bridges ,but vertical gradient temperature may easily result in the crack of the hinge joints in assembly hollow slab bridge .In order to solve this problem ,this paper proposed a transverse prestress preloading method to prevent crack .By using ABAQUS finite element software the entity model of assembly hollow slab bridge was developed ,then the cracking causes of assembly hollow slab bridge and the crack resistance of assembly hollow slab bridge after applying transverse prestress was analyze .The results show that under the action of vertical temperature gradient , great tensile stress produced at the section of hollow slab bridge ,and become the important factors in the early cracking of the hinge joints .Second ,prestress in the transverse for assembly type hollow slab bridge can eliminate the tensile stress on the section of hinge joints cause by the vertical gradient temperature ,and make prestress on the section of hinge joints to improve the crack resistance of the bridge .The research conclusion can provide references for solving the diseases of hinge joints in assembly hollow slab bridge .