在役空心板梁桥底板纵向裂缝成因及处治对策分析

结合江苏省内某高速公路全线桥梁的定期检查及病害调研,总结了空心板梁桥底板纵向裂缝的一般特征,从设计、施工和运营等方面分析了底板纵向裂缝的成因。根据底板纵向裂缝的分布性状、板梁底板厚度不足及板梁自身渗漏水等实际情况,提出了底板纵向裂缝的灌浆处治对策,该处治对策的有益效果在于可主动封闭纵向裂缝、抑制板梁渗漏水进入裂缝内部以及防止预应力钢绞线锈蚀。该法能够提高空心板梁桥结构的耐久性和安全性,具有普遍的针对性和实用性。最后,详细阐述了灌浆施工工艺、流程及其注意事项。该项底板纵向裂缝的灌浆处治对策可被同类桥梁工程借鉴。

Cause Analysis and Treatment Measure on Bottom Longitudinal Crack of In-service Hollow Slab Girder Bridges

Combining with the periodic inspection and disease investigation on the whole line bridges of one ex- pressway in Jiangsu Province, this paper summarized the general characteristics of the bottom longitudinal crack in hol- low slab girder bridges and analyzed its causes from design, construction, operation and some other aspects. According to actual situation of the distribution characters of the bottom longitudinal crack, thickness defwiency of the bottom plate and water leakage of the slab girder itself, etc. , a grouting treatment measure for the bottom longitudinal crack was proposed, which has beneficial effects on closing the longitudinal crack actively, inhibiting slab girder＇s water leakage into the internal of the crack and preventing the prestressed strand from corrosion. The method can improve the hollow slab girder bridge structure＇s durability and safety and has universally pertinent and practical property. Final- ly, the grouting construction technology, process and its precautions was described in details. The grouting treatment measure for the bottom longitudinal crack can be used popularly in the same type bridge project.