基于不同围岩特性的月牙肋钢岔管联合承载研究

Research on Crescent Rib Steel Bifurcation Joint Bearing Based on Different Surrounding Rock Characteristics

月牙肋岔管和围岩的联合承载比例与结构的受力有密切关系,围岩弹性抗力系数K是影响其联合承载的重要因素。为研究与围岩联合承载状态下岔管的复杂应力分布规律,以某抽水蓄能电站为例,建立三维月牙肋钢岔管数值仿真模型,考虑定常间隙值的影响,研究不同K值对钢衬应力、围岩应力、接触滑移状态及联合承载比的影响。结果表明:岔管钢衬与围岩存在一定间隙的情况下,合理的围岩弹性抗力系数对于改善管壳应力分布和变形有着良好的作用,选择0.5 N/mm 3作为钢岔管的临界围岩弹性抗力系数,既可充分利用钢岔管的材料强度,又能发挥围岩联合承载能力。

The joint bearing ratio of crescent rib bifurcated pipe and surrounding rock is closely related to the stress of structure,and the elastic resistance coefficient(K value)of surrounding rock is an important factor affecting the joint bearing.In order to study the complex stress distribution law of bifurcated pipe under the condition of joint bearing with surrounding rock,a three-dimensional numerical simulation model of crescent rib steel bifurcated pipe is established for a pumped-storage power station.The influences of different elastic resistance coefficient of surrounding rock on the stress of steel lining,surrounding rock stress,contact slip state and joint bearing ratio are studied considering the influence of constant clearance value.The results show that the reasonable elastic resistance coefficient of surrounding rock plays a good role in improving the stress distribution and deformation of the shell when there is a certain gap between the steel lining of bifurcated pipe and surrounding rock.In this case,when selecting 0.5 N/mm 3 as the critical surrounding rock elastic resistance coefficient of steel bifurcation,it can not only make full use of the material strength of steel bifurcation,but also can play the role of the joint bearing capacity of surrounding rock.