单索面斜拉桥钢—混组合索塔施工抗风性能研究  

Research on Wind-resistance of the Steel-concrete Composite Pylon for Single Cable-plane Bridge during Construction

作　　者：张茜[1,2] 冯宗朝 赵呈涛[1] 

机构地区：[1]长安大学公路学院,西安市710064 [2]兰州大学土木工程与力学学院,兰州市730000 [3]大榭大桥有限公司,宁波市315812

出　　处：《公路》2013年第9期286-292,共7页Highway

摘　　要：大榭第二大桥为单索面斜拉桥,为了验证其钢—混组合索塔在施工过程中的抗风安全性,采用有限元数值分析方法,对索塔在下横梁浇筑前、上横梁浇筑前、裸塔阶段等3种施工控制状态,在20年一遇台风作用下的静阵风荷载响应进行了分析,并进一步分析了裸塔状态下施加临时风缆后对抗风性能的改善情况。研究结果表明:索塔施工过程中风荷载作用下产生的最大拉应力出现在裸塔阶段,位于横桥向迎风侧中塔柱根部,与恒载效应组合后,最大拉应力值为5.04MPa,;最大拉应力产生的裂缝宽度为0.067mm,小于规范规定的限值(0.15mm);裸塔状态下施加临时风缆可以显著减小混凝土塔柱的最大拉应力。Daxie Second Bridge is a cable-stayed structure with single cable plane. The finite element model analysis method is used in order to verify the wind-resistance safety of its steel-concrete composite pylon in the construction stage. In three pylon construction control states encountered a typhoon of 20 years return period, the response of the static gust toad is analyzed, which are lower beam before casting, upper beam before pouring, and bare pylon. Further analysis of the improvement to the wind resistance by applying temporary wind cable in the state of bare pylon is made. The results show that： the maximum tensile stress of pylon caused by wind loads in the construction stage occurs on the stage of the bare pylon, and locates in the windward side of the middle pylon roots in the transverse bridge direction. Combined with the effects of dead loads, the maximum value of tensile stress is 5.04 MPa; the crack width is 0. 067 mm caused by the maximum tensile stress, and it is less than the limit of 0.15 mm required by specification; applying the temporary wind cable in the stage of the bare pylon can significantly reduce the maximum tensile stress of concrete pylon.

关 键 词：斜拉桥 索塔 静阵风荷载 裂缝宽度 施工过程 

分 类 号：U441.4[建筑科学—桥梁与隧道工程]