矮塔斜拉桥施工控制技术研究

发布时间：2018-10-15 12:02

【摘要】：随着桥梁事业的蓬勃发展,新的桥梁结构形式不断涌现,矮塔斜拉桥就是一个典型代表,其受力性能介于连续梁桥和斜拉桥之间,且造型新颖、组合形式丰富、易与环境融合,因此在国内外得到了广泛应用。为了保证结构在施工过程中的安全、成桥状态结构内力和线形满足设计目标,对矮塔斜拉桥进行施工控制研究有着重要的现实意义。以常山大桥为工程背景,首先运用有限元分析软件Midas/Civil建立基于梁单元的有限元模型,并使用正装迭代法求解合理施工索力。在此基础上,对全桥施工过程进行仿真模拟,计算分析了结构在各施工阶段的内力和变形,由此验证施工方案的合理性。同时,针对平行钢绞线斜拉索体系,以无应力状态法为理论核心计算出单根钢绞线张拉力大小,保证钢绞线之间索力的均匀性,实现等值张拉。其次,对矮塔斜拉桥施工控制过程中各影响参数进行敏感性分析,获取主要敏感性参数,并根据现场测试结果分析误差原因,采用最小二乘法进行参数识别,并将修正后的参数反馈到模型中,使得有限元模型与实际结构力学响应逐渐逼近。最后,根据常山大桥的施工控制方案,详细介绍了本桥线形和应力的控制方法,通过立模标高和斜拉索初张拉大小指导梁段施工。通过控制结果分析,可知施工过程线形满足要求,应力处于安全可控范围,成桥结构满足设计预期要求。
[Abstract]:With the rapid development of the bridge industry, new bridge structure forms are emerging constantly, the short tower cable-stayed bridge is a typical representative, its mechanical performance is between continuous beam bridge and cable-stayed bridge, and the shape is novel, the combination form is rich, easy to blend with the environment. Therefore, it has been widely used at home and abroad. In order to ensure the safety of the structure during the construction process, the internal force and the linear shape of the state structure of the bridge meet the design objectives, so it is of great practical significance to study the construction control of the cable-stayed bridge with low tower. Taking Changshan Bridge as the engineering background, the finite element model based on beam element is established by using finite element analysis software Midas/Civil, and the rational construction cable force is solved by means of formal iteration method. On this basis, the construction process of the whole bridge is simulated, and the internal force and deformation of the structure in each construction stage are calculated and analyzed, which verifies the rationality of the construction scheme. At the same time, aiming at the cable system of parallel steel strand, the tensile force of a single strand is calculated with the stress free state method as the theoretical core, so as to ensure the uniformity of the cable force between the steel strands and to realize the equivalent tensioning. Secondly, the sensitivity analysis of the influence parameters in the construction control process of the low tower cable-stayed bridge is carried out, the main sensitivity parameters are obtained, and the error causes are analyzed according to the field test results, and the least square method is used to identify the parameters. The modified parameters are fed back to the model, which makes the finite element model approach to the actual structural mechanical response. Finally, according to the construction control scheme of Changshan Bridge, the control methods of the bridge alignment and stress are introduced in detail. The construction of the beam section is guided by the elevation of the vertical formwork and the initial tension size of the stay cable. Through the analysis of the control results, it can be seen that the line shape of the construction process meets the requirements, the stress is in the safe and controllable range, and the bridge structure meets the expected design requirements.
【学位授予单位】：东北林业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U445.4;U448.27

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