流体压力对沉降场地输液管网应变特性的影响

Effects of fluid pressure on strain properties of liquid-conveying pipe network in settlement site

管内流体压力和场地变形影响着管网力学性能.设计小型埋地输液管网室内试验模型,利用MTS加载装置模拟场地不均匀沉降,研究管内流体压力对管网应变特性的影响.通过分析不同流体压力和场地沉降作用下管网的应变、变形等试验结果,得出:场地沉降中心或附近的管网应变最大,易破坏;在一定的压力范围内,管网内部流体压力越大,管网应变越小,管网抵抗场地破坏能力越强;分支管道的存在使得三通连接处的管道受力发生变化,容易产生应力集中现象,且靠近沉降中心位置的管段变形严重,而分支处的支管道变形较小,抵抗破坏能力较强.

Fluid pressure within pipes and site deformation influence the mechanical properties of buried pipe network.By designing an experimental model of small buried pipe network in the laboratory and simulating the uneven settlement by loading equipment-MTS,the effects of internal fluid pressure on the strain properties of buried pipe network were investigated.By analyzing the experimental results of strain and deformation of pipes under the effects of fluid pressures and site subsidence,the following conclusions are reached.In general,pipes at or near the center of subsidence region are easily damaged whose strain is the largest.Within a span of pressure,the more the internal pressure within pipe network,the less strain and the greater resistance of pipe network is to site damage.But the existence of branch pipe makes the stress concentration of the pipe at the T-junction,and serious deformation near the center of subsidence region,which is easily destroyed.As the deformation of branch pipe at the T-junction is less,its capacity for resisting damage is stronger.