摘要
对南京地铁2号线东延高架线路采用的U型梁进行结构计算,以及1∶1静载试验和1.9m模型梁试验。结果表明:在设计荷载下,跨中处道床板底部的横向拉应力超过C55的极限抗拉强度。建议适当增加道床板底部的横向配筋率。静载试验中,各加载工况下的U型梁纵向裂纹发展满足规范要求。模型梁试验结果表明,钢筋在设计寿命内不会发生疲劳失效。从裂缝控制角度而言,U型梁等效运营时间大于33年。
According to the structural characteristics of U-beam in partial elevated sections of Nanjing metro Line 2(the east extension),this paper introduces the results of the structural calculation,the static load test(1∶1)and the model test of U-beam,which showed that the transverse tensile stress at the bottom of ballast slab midspan exceeded the ultimate tensile strength of C55 concrete.So,the transverse reinforcement ratio at the bottom of ballast slab should be increased properly.The results also showed that the development of longitudinal crack in U-beam could meet the standards in every process of static load test.The model tests showed that the fatigue failure of steel would not happen within its design life and the service time of U-beam will be possibly beyond 33 years while considering the crack control.
出处
《城市轨道交通研究》
北大核心
2009年第8期8-12,共5页
Urban Mass Transit
关键词
地铁
高架线路
U型梁
结构计算
静载试验
模型试验
metro
elevated line
U-beam
structural calculation
static load test
model test
