斜拉桥节段纵移悬拼法足尺模型试验研究

发布时间：2018-06-02 15:37

本文选题：桥梁工程 + 主梁架设　；参考：《公路交通科技》2017年05期

【摘要】：为验证节段纵移悬拼工艺的可行性、合理性及可操作性,研究施工过程中结构的动力响应,以北盘江大桥为背景进行了足尺模型试验,试验工况涵盖了工艺中每个不确定的、有待验证的状态;并基于耦合系统动力分析理论,将结构简化为两自由度的弹簧-质量块振动系统,建立了试验过程大系统动力学方程进行理论计算,动力模型包含了5个典型动力状态,即地面提升、运梁小车纵向运输、运梁小车与桥机吊点协同前进、桥机吊点前移、桥机整体提升。研究结果表明:各工序下运梁轨道及主桁架测点加速度幅值较小,桥面吊机吊点前移时结构响应最为显著,桥面吊机端部最大加速度为0.212g;轨道梁测点的最大加速度方向为纵向,下弦杆测点的最大加速度方向为竖向,高速挡下轨道梁测点的纵向、竖向加速度实测幅值较低速档分别增大约54%,51%,下弦杆测点的纵向、竖向加速度实测幅值较低速档分别增大约31%,36%,轨道梁应力峰值在高速挡时也有所增大,跨度最大位置的测点对车速最为敏感;测点理论竖向加速度幅值、理论轨道梁应力峰值与实测值吻合较好,验证了理论模型的准确性;试验过程平稳且连贯性较好,节段纵移速度快、整体对接耗时少,较散拼法有较明显的工期优势。
[Abstract]:In order to verify the feasibility, reasonableness and maneuverability of the segmental longitudinal suspension assembly technology, and to study the dynamic response of the structure during the construction process, a full-scale model test was carried out with the Beipanjiang Bridge as the background, and the test conditions covered every uncertain part of the process. Based on the coupled system dynamic analysis theory, the structure is simplified to a two-degree-of-freedom spring-mass vibration system, and the dynamic equation of the large-scale system is established for theoretical calculation. The dynamic model consists of five typical dynamic states, namely, ground lifting, longitudinal transport of beam carrier, coordinated advance of beam carrying vehicle and lifting point of bridge machine, forward moving of suspension point of bridge machine, and overall lifting of bridge machine. The results show that the acceleration amplitude of the moving beam track and the main truss is small, the structural response is the most obvious when the lifting point of the bridge deck crane moves forward, the maximum acceleration at the end of the bridge deck crane is 0.212g, and the maximum acceleration direction of the measuring point of the track beam is longitudinally. The maximum acceleration direction of the measuring point of the lower chord is vertical, and the measured amplitude of the vertical acceleration of the high-speed track beam increases by 54 ~ 51s than that of the low-speed track beam, respectively, and the longitudinal value of the measuring point of the lower chord, The measured amplitude of vertical acceleration is increased by about 31 / 36 and the peak stress of track beam also increases at high speed, and the measuring point of the largest span position is most sensitive to the speed of the vehicle, and the theoretical vertical acceleration amplitude of the measuring point is also increased. The accuracy of the theoretical model is verified by comparing the peak stress value of the theoretical track beam with the measured value, and the experimental process is stable and consistent, the segment longitudinal moving speed is fast, the whole docking time is less, and the theoretical model has obvious advantages over the scattered spelling method.
【作者单位】：长沙理工大学桥梁工程湖南省高校重点实验室;长沙理工大学土木与建筑学院;贵州省公路工程集团有限公司;
【基金】：国家自然科学基金项目(51178059,51678068) 重点基础研究发展计划(九七三计划)项目(2015CB057706) 长沙理工大学桥梁工程湖南省高校重点实验室开放基金项目(14KD09,15KB03) 湖南省研究生科研创新项目(CX2015B343)
【分类号】：U448.27

【相似文献】