合安高速公路某预应力混凝土空心板桥,因桥下拾荒堆积物起火燃烧,造成第三跨下行11块板梁损伤严重。由于混凝土被烧酥、爆裂、剥落、开裂,造成强度降低,构件的刚度减小,桥体的质量和使用寿命受到一定程度的影响。结合这一实际工程,本文综合运用混凝土结构基本理论、火灾损伤理论、结构试验检测技术、混凝土加固理论以及施工控制技术等理论和方法。 A prestressed concrete hollow slab bridge in He’an Expressway, due to fire and burning of the piled up debris under the bridge, caused serious damage to the 11 slab beams with the third cross-down. As the concrete is crisp, burst, spalling, cracking, resulting in lower strength, stiffness of components to reduce the quality and service life of the bridge to some extent affected. Combining with this practical project, this article synthetically applies theories and methods such as basic theory of concrete structure, fire damage theory, structure test and detection technology, concrete reinforcement theory and construction control technology.