空心板梁桥火灾后承载力评估

Evaluation of Bearing Capacity on Hollow Slab Beam Bridge After Fire

为了研究火灾后混凝土桥梁的力学性能,以火灾后某钢筋混凝土空心板桥为工程背景,根据火灾后该桥混凝土的颜色、裂缝、脱落情况及锤击反应对桥梁进行了火灾鉴定.为评估火灾后桥梁的承载能力,还测量了该桥受火梁段在静力试验荷载作用下的挠度值、应变值及裂缝的分布状况.鉴定及试验结果表明桥梁刚度有所下降,但桥梁整体仍处于弹性阶段,并不影响结构安全.为保证桥梁长期运营的安全性,建议对梁底损伤部位进行处理.

In order to study the mechanical properties of damaged fire about concrete bridge,this paper regarded areinforced concrete hollow slab bridge as the engineering background after the fire. According to the color,cracks,shedding and hammering response of concrete of the bridge,fire identification was carried out. In order to evaluatethe bearing capacity of the bridge after the fire,the deflection value,the strain value and the distribution of thecrack of the bridge under the static load are measured. The results showed that the stiffness of the bridge was declined,but the bridge was still in the elastic stage,which didn＇t affect the safety of the structure. In order to ensure the safetyof long-term operations of the bridge,this paper recommended to treat the burn site at the bottom of the beam.