朔黄铁路32 m超低高度预应力混凝土简支T梁适应30 t轴重货车加固改造分析

摘要

T hrough the calculations of 32 m-span super-low height prestressed concrete simply-supported T-girder on the Shuozhou-Huanghuagang railway under 30-ton heavy haul railway,it indicated that the actual force-bearing performance and the stiffness of the girder could not meet the requirement of the rating standard,thus demanding the strengthening and retrofit. A reinforcing method with a pre-bent steel beam was selected. T he original concrete girder and the pre-bent steel beam were combined to a composite structure,and the deflection of the composite structure was coordinated under live load. It indicated that the crack resistance,the strength and the vertical stiffness meet the requirement of the current rating code,proving its reinforcement effect.%对朔黄铁路跨度32 m超低高度预应力混凝土简支 T梁适应轴重30 t及以上重载货车(1．2倍ZH (2010)活载)进行了检算分析，结果表明梁体的竖向刚度和力学性能已不能满足现行铁路规范的要求，需对桥梁进行加固改造。选取顶升预弯辅助钢梁的加固方案，使原混凝土梁和预弯辅助钢梁组成组合结构，在活载作用下二者跨中挠度协调一致，在30 t轴重活载作用下梁体的抗裂性、强度和竖向刚度等各项关键指标均满足现行规范要求，能够达到预期加固效果。