桥梁桩基础施工对航道演变影响分析

近年来多座桥梁建设期间工程河段航道发生了明显变化。针对这一问题,以荆岳长江公路大桥桥墩基础施工阶段为例,对比施工前后的实测水文、地形。结果发现桩基施工时搭设的栈桥、水上施工平台引起丁家洲边滩和南阳洲洲头发生较大改变,加速了局部河段航道条件向不利方向发展的趋势,说明桥梁基础施工对航道演变有较大影响。为尽量避免不利影响,在前期跨度研究阶段,应提前考虑可能采用的施工方案对航道的影响。如果通过调整施工方案难以消除或者减小影响,必须优化桥跨和桥墩布置方案。分析成果可为后续桥梁建设管理提供参考借鉴。

Influence of pile foundation construction of cross-river bridges on channel evolution

In recent years,during the construction of many bridges,obvious changes have taken place in the channel of the project reach.In order to solve this problem,taking Jingyue Yangtze River Highway bridge pier foundation construction stage as an example,the measured hydrology and topography before and after construction are compared.The results show that the trestle and water construction platform set up during pile foundation construction have caused great changes in Dingjiazhou beach and Nanyangzhou head zone,and has accelerated the development trend of channel conditions in some reaches to the adverse direction,which shows that bridge foundation construction has a great impact on channel evolution.In order to avoid the adverse effect as far as possible,the influence of the possible construction scheme on the channel should be considered in advance in the early stage of span study.If it is difficult to eliminate or reduce the impact by adjusting the construction scheme,the layout scheme of bridge span and pier must be optimized.The analysis results can provide reference for subsequent bridge construction management.