受腐蚀超大排水箱涵安全评估与力学性能研究

SAFETY ASSESSMENT AND MECHANICAL PROPERTY STUDY OF CORRODED LARGE-SPAN DRAINAGE CULVERT

基于规范法和有限元方法分别建立了受损箱涵的计算模型,对不同损伤状态进行受力计算,并基于有限元计算结果分析受腐蚀箱涵的破坏模式,提出受腐蚀箱涵的极限承载力界定方法,讨论箱涵受力性能随损伤程度的变化规律。研究表明,箱涵腐蚀后,顶板跨中的抗弯能力大幅降低,远不能满足规范要求,但这一抗弯能力缺口在一定程度上可通过消耗两腋角的抗弯能力来弥补,并对有腐蚀风险的排水箱涵提出针对性的加固及保护建议。

The mechanical model of a typical corroded culvert is established by both code method and numerical method （FEM, finite element method） separately, on which a variety of damage states are evaluated. Based on the evaluation results, the failure mode of the corroded culvert is analyzed, then a method to define its ultimate bearing capability is presented, and the regularity between the degree of damage and the mechanical property of the culvert is discussed. The study indicates that the bending capability of the mid-section of the ceiling slab is significantly weakened after the major corrosion and is fail according to the code, but this can be partly made up by consuming the bending capability of the hunch area. Finally, this paper proposes several suggestions on the fastening and protection of drainage culverts that suffer such corrosion-related damage.