大跨径连续刚构桥裂缝成因分析与梁体加固设计

Analysis of crack causes and girder reinforcement design for large span continuous rigid frame bridge

箱梁腹板斜裂缝及顶底板纵向裂缝已成为大跨径预应力混凝土连续刚构桥梁在运营过程中的常见病害之一。本文依托某大跨径预应力混凝土连续刚构桥,运用有限元分析软件MIDAS/CIVIL及MIDAS/FEA建立数值模型,分析主桥箱梁腹板斜向裂缝、顶底板下缘纵向裂缝及跨中下挠变形原因。在病害成因分析基础上提出了预张紧钢丝绳网片及粘贴碳纤维布的加固设计方案,制订了加固关键工序施工工艺流程,并对施工工艺进行了详细论述。

During the operation of long-span prestressed concrete continuous rigid bridges,oblique cracks of box girder web and longitudinal cracks of roof and floor have become one of the common diseases.This paper relies on a long-span prestressed concrete continuous rigid bridge,to established a numerical model by using the finite element analysis software MIDAS/CIVIL and MIDAS/FEA to analyze the oblique cracks of the box girder web of the main bridge,the longitudinal cracks of the lower edge of the top and bottom plates,and the deflection deformation of the middle and lower spans.Based on the analysis of disease causes,the reinforcement design scheme of pre-tensioned steel wire rope mesh and pasted carbon fiber cloth was proposed,the construction process of the key reinforcement process was formulated,and the construction process was discussed in detail.