横向预应力与压浆加固装配式空心板梁桥试验研究

Test and Study of Assembly Hollow Slab Bridges Strengthened with Transverse Prestressing and Grouting

提出横向预应力+压浆加固装配式空心板梁桥技术,并进行了一座桥梁模型的试验研究,结果表明:铰缝损坏后,各板之间横向传力性能降低,横向分布系数变化不均;横向预应力加固后,最大的横向分布系数减小,横向受力不均现象得到了显著地改善,但加固后的受力性能达不到铰缝完好状态;预应力+压浆加固修复后,桥梁的铰缝剪力传递能力能够得到完全地恢复,相应桥梁模型的横向受力性能完全恢复至铰缝完好状态。横向预应力对铰缝损坏的桥梁横向加固,提高了铰缝损伤界面的机械咬合力与摩擦力;压浆对铰缝损坏的桥梁横向加固,修复了铰缝内破损混凝土,进而有效地恢复桥梁结构的横向连接性能;预应力+压浆加固综合了横向预应力加固技术和压浆加固技术两者的优点。

This paper presents a technology to strengthen assembly hollow slab bridges with bothtransverse prestressing and grouting. An experimental study of a bridge model is conducted. The resultsshow that the shear force transmission ability decreases and the transverse distribution coefficients changeunevenly after the hinge joints are damaged. When the bridge is strengthened by transverse prestressing,the maximum transverse distribution coefficients decreases and the unevenly load carrying phenomenon isimproved, but the transverse mechanical performance of bridge cannot be restored to the state with theundamaged hinge joints. When the bridge is strengthened by both transverse prestressing and grouting,the shear force transmission ability can be fully restored and the transverse mechanical performance ofbridge is well restored to the state with the undamaged hinge joints. Transverse prestressing improves themechanical interaction and the friction between the interfaces of damaged hinge joints for bridges, andgrouting renovates concrete in damaged hinge joints and restores the transverse connecting performance.The technology using both transverse prestressing and grouting to strengthen bridges combines theadvantages of the both technologies.