空心板梁使用阶段底板应力分析及纵向裂缝成因研究

针对先张法预应力空心板梁底板纵向裂缝病害往往在使用阶段才出现这一现象，提出纵向裂缝形成与使用阶段活载作用有重要联系；通过对使用阶段车辆荷栽作用下板梁的横向应力情况进行计算，并以桥梁宽跨比、板梁底板厚度为可变参数，分析活载作用下纵向裂缝形成的规律；探讨得出使用阶段板梁底板纵向裂缝形成的原因，提出针对性处治措施。

Study on Floor Stress of Hollow Plate Beams and Causes of Longitudinal Cracks in Service Stage

Considering that longitudinal cracks on the floor of pre-tensioned prestressed hollow slabs are usually occurred in service stage, the live load which should be a quite important factor is proposed. Based on the calculation of transverse stress on the floor in service stage, the forming process of longitudinal cracks is analyzed, while the width-span ratio and the thick- ness of the floor are both considered as variable parameters. Then the causes of longitudinal cracks are discussed and demonstrated, and several treatments are proposed.