中文摘要：

为快速评定混凝土梁桥的承载能力,采用截面非线性全过程分析方法,得到通用图中桥梁关键截面的弯矩与开裂高度的对应函数,并建立裂缝特征库;根据更详细的裂缝调查和预先构建的裂缝特征库及效应或抗力库,通过查图表确定新的承载能力检算系数Z3,嵌入中国规范体系,并对抗力进行修正,从而实现对混凝土梁桥承载能力的快速、准确评定。研究结果表明：对于RC梁桥,稳定的裂缝高度也可能蕴藏很大危险;对于PC梁桥,利用裂缝高度评估结构承载能力是否满足规范要求的方法适宜性较好;提出的方法可预警普通钢筋和预应力钢筋是否屈服,从而确定是否需要限制交通或封闭交通,尤其在桥梁安全预警、大件运输及旧、危桥改造等领域具有明显优势。

英文摘要：

In order to evaluate the load-bearing capacity of concrete beam bridge rapidly, the relationship between moment and crack height was obtained with nonlinear section analysis of key bridge sections in general drawings, and the crack feather library was established. A new modification coefficient Z3 was determinated just by lookup table and charts of pre-built crack feather libraries and effect or resistance libraries, which was embedded in system of norms to modify the resistance, so rapid evaluation of load-bearing capacity of concrete beam bridges was achieved. The results show that stable crack height may also bear great danger for RC bridges. It is suitable for PC beam bridges to evaluate whether the load-bearing capacity meeting the regulatory requirements. The proposed method can guarantee safety early warning for reinforcement and prestressed reinforcement yield, and then determine whether it is necessary to restrict traffic or close traffic. The method has obvious advantages in the field of bridge safety warning, overweight ＆ oversize cargo transportation and reconstruction of old bridges in dangerespecially.