缆索吊装混凝土拱桥施工过程的稳定性分析

发布时间：2018-05-08 12:07

本文选题：混凝土拱桥 + 缆索吊装　；参考：《重庆交通大学》2014年硕士论文

【摘要】：通过查阅大量文献,本文详细阐述了钢筋混凝土拱桥的发展现状和大跨径钢筋混凝土拱桥的施工方法,对缆索吊装施工技术作了简要介绍。缆索吊装施工技术在受到广泛运用的同时,施工过程中拱肋的稳定性已成为一个无法回避的重要课题。论文依托龙门大桥实际工程从拱箱安装阶段和单拱肋合拢后两个施工阶段对拱肋的稳定性进行了理论分析。着重分析研究拱肋在吊装过程中所处的不利状态(拱脚段拱箱安装悬挂状态、次拱脚段拱箱悬挂状态、次拱顶段安装悬挂状态)下的稳定问题。对混凝土拱肋合拢状态下的稳定性分析时,采用按照规范求解计算和利用有限元软件建模计算两种计算方式。得到以下结论：①单拱肋合拢后,拱肋在自重作用下其纵向稳定性和横向稳定性都均能满足规范要求；②在拱肋两侧设置浪风索,能显著提高拱肋的横向稳定性。对吊装阶段的拱肋稳定性分析时,通过改变浪风索索力研究拱肋受横向风荷载作用下螺栓拉力的变化情况。由计算可知,浪风索索力与接头处螺栓所受拉力成线性关系；距离接头处较远的浪风索对该接头螺栓受力的影响更为明显。对混凝土拱箱吊装阶段的稳定性分析时,采用有限元分析的方法研究了拱肋的横向偏移对拱肋稳定性的影响。得出下列结论：①在50年一遇风荷载作用下,与拱座接触的拱脚段拱箱混凝土发生弹性变形,各接头处连接螺栓受力也能够满足承载力要求,拱肋在吊装阶段不会发生失稳；②吊装拱脚段拱箱时,拱肋不发生横向失稳的横向偏移角的范围为0～2°；③吊装次拱脚段拱箱时,拱肋不发生横向失稳的横向偏移角的范围为0～0.9°；④吊装次拱顶段拱箱时,拱肋不发生横向失稳的横向偏移角的范围为0～0.3°。
[Abstract]:By consulting a large number of documents, this paper expounds in detail the development of reinforced concrete arch bridge and the construction method of long span reinforced concrete arch bridge, and briefly introduces the construction technology of cable hoisting. With the wide application of cable hoisting construction technology, the stability of arch rib in construction process has become an important issue that can not be avoided. Based on the actual project of Longmen Bridge, the stability of arch rib is analyzed theoretically from the two construction stages of arch box installation stage and single arch rib closure stage. The stability of arch ribs under the unfavorable conditions (arch foot arch box installation and suspension, secondary arch foot arch box suspension, secondary arch roof installation and suspension) during hoisting process is analyzed and studied emphatically. In the analysis of the stability of concrete arch rib under the condition of closure, two calculation methods are adopted, which are to solve the problem according to the specification and to model and calculate by using finite element software. It is concluded that the longitudinal and transverse stability of the arch rib under the action of self-weight can meet the requirements of the specification and that the transverse stability of the arch rib can be significantly improved by installing wave wind cables on the two sides of the arch rib after the closure of the one-arch rib at the ratio of 1: 1. In the analysis of the stability of arch rib in hoisting stage, the change of bolt tension under transverse wind load is studied by changing the cable force of wave wind. It can be seen from the calculation that the cable force is linear with the tensile force of the bolt at the joint, and that the influence of the wind cable far away from the joint on the stress of the joint bolt is more obvious. In the stability analysis of concrete arch box during hoisting stage, the influence of transverse deviation of arch rib on the stability of arch rib is studied by finite element method. The following conclusions are drawn: 1 under the action of 50 years wind load, the arch box concrete in contact with the arch seat has elastic deformation, the connection bolt at the joint can also meet the bearing capacity requirements, and the arch rib will not lose stability in the hoisting stage; (2) when the arch box is hoisted, the transverse deviation angle of the arch rib does not occur transverse instability in the range of 0 ~ 2 掳/ 3 when the arch box is hoisted with the secondary arch foot section, and the transverse deviation angle of the arch rib does not occur when the transverse displacement angle of the arch rib is 0 ~ 0.9 掳/ 4 when the sub-arch box is hoisted, The range of lateral deviation angle of arch rib without transverse instability is 0.3 掳.
【学位授予单位】：重庆交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U448.22;U445.4

【参考文献】