预应力FRP网格加固混凝土空心板的张拉工法及其抗弯性能试验研究

Practical Calculation Method Research on Axial Tensile Force Transfer Coefficient of Steel Beams at Joints Connecting Steel Frame and Concrete Core Tube

FRP网格拥有双向纤维筋,刚度较低,强度较高,是一种线弹性材料,相比于FRP片材加固抗剥离性能与耐火性能更好。预应力FRP网格加固技术可以有效改善结构力学性能,充分发挥FRP网格强度高的特点,进一步抑制结构变形和裂缝扩展。设计了一套预应力FRP网格的张拉工法,利用波纹型夹片式锚具完成了网格的张拉,并介绍预应力FRP网格加固混凝土空心板的流程。同时进行了两根FRP网格加固空心板的抗弯性能试验,结果表明使用预应力FRP网格加固后的空心板,其开裂荷载、屈服荷载与极限承载力相对于基准板提高了76%,81%,77%。

FRP grid has two-way fiber ribs, low stiffness, high strength, is a linear elastic material.It has better anti-stripping performance and fire resistance compared to FRP sheet. Prestressed FRP grid reinforcement technology can effectively improve the structural mechanical properties, give full play to the characteristics of high FRP grid, and further inhibit the structural deformation and crack propagation.we designed a set of prestressed FRP grid tension method, completed the grid tension by using corrugated clip- type anchor and make introduction to the process of strengthening.The prestressed FRP grid flexural reinforcement test were carried out on two hollow slabs, and the failure characteristics and failure mechanism of the hollow plate were studied.The results show that the cracking load, the yield load and the ultimate bearing capacity of the prestressed FRP grid are increased by at 76%,81% and 77% respectively.