土-管-水耦合作用效应及埋地供水管道地震伤损机理

Water supply pipeline is an important part of urban lifeline engineering, but the damages of buried water supply pipeline have an important impact on the safety of water supply, these damages are as the main form of rupture, broken and loose joints. At present, seismic damage mechanism of buried pipeline was studied more based on pipe-soil interaction, but there was lack of the systematic research on the seismic damage problem of buried water supply pipeline based on the consideration of soil - pipe - water interaction at home and abroad, furthermore, the real seismic date show that the Wenchuan earthquake damage of pipelines with pressure water conditions is particularly prominent.. This project aims to the seismic damages of water supply pipeline in different site conditions, through the analysis of deformation characteristics of buried water supply pipelines under earthquake, put forward reasonable soil-pipe-water interaction physical model with comprehensive consideration pipe-soil interaction and fluid-structure interaction, the physical model parameters and seismic damage mechanism of buried water supply pipelines under different conditions were proved by shake table tests, numerical simulation method was studied according to the characteristics of soil - pipe - water interaction physical model, and the seismic damages conditions and development mechanism were studied through the numerical analysis and experiments research, so as to explain the damage mechanism and development mechanism of buried water supply pipelines from the whole theory. The research will be helpful to further enrich and perfect the theory of damage of buried water supply pipelines.

供水管道是城市生命线工程的重要组成部分，但以管道断裂、破损、接头松动等为主要形式的伤损问题会对供水安全产生重要影响。目前，国内外对基于管土相互作用理论的埋地管道伤损机理开展了较深入的研究，但是基于土-管-水耦合作用的伤损问题还缺乏系统的研究，而汶川地震的实震资料表明在有压水条件下埋地管道的伤损问题尤为突出。本项目拟针对不同场地条件下埋地供水管道的伤损问题，通过分析埋地供水管道在地震作用下的变形发展特点，提出合理的综合考虑管土相互作用和管水流固耦合作用的土-管-水耦合作用物理模型，利用振动台试验探明埋地供水管道在不同条件下的物理模型参数取值以及伤损机理，根据土-管-水耦合作用物理模型特点研究其数值模拟计算方法，并通过数值分析和试验研究埋地供水管道伤损条件和发展机制，从而从整体理论上对埋地供水管道的伤损机理和发展机制进行解释。研究成果将为进一步丰富和完善埋地供水管道的伤损理论提供参考。

地震作用下埋地供水管道的伤损问题非常普遍，地震的实震资料表明在有压水条件下埋地管道的伤损问题又尤为突出，国内外对基于管土相互作用理论的埋地管道伤损机理研究很重视，本项目针对基于土-管-水耦合作用的伤损问题进行了系统深入研究。首先，我们在分析总结了埋地供水管道的地震灾害资料基础上，结合管土相互作用理论和流固耦合理论建立了土-管-水耦合作用动力学计算模型；其次，利用有限元方法计算分析了地震作用下管流自振周期、场地条件、管道埋深、管长、管径、壁厚、管材以及流体参数和地震参数等对供水管道内动水压力的变化规律特性，开展了管-土相互作用试验研究，获得了不同管材的管土阻力大小及等效土弹簧系数值；最后，对埋地供水管道在地震作用下伤损的形成与发展机制进行了研究，分析了余震次数与烈度大小对伤损段发展的影响。项目成果中地震作用下埋地供水管道的土-管-水耦合动力学分析理论模型以及埋地供水管道内的地震动水压力变化规律特性，在理论上取得了较大突破，具有较高的学术价值；管道的伤损发展预测与结构整体寿命评估对于埋地管道维修时机的确定也具有很高的应用价值。目前，成果总体情况：已发表论文4篇，已录用待刊2篇，申请发明专利1项，已培养毕业研究生4名，2名待答辩。