高级检索

真空管道双层衬砌结构力学特性研究

Mechanical Properties of Evacuated Tube Transport Double Lining Structure

  • 摘要: 为了保证真空管道运输系统的密封性能,提出了盾构管片与二次衬砌组合的真空管道结构。基于双层衬砌数值仿真模型,以上海淤泥质粘土为模拟地层,分别分析了复合式衬砌结构和叠合式衬砌结构真空管道的内力分布。在与常规盾构隧道内力对比的基础上,分析了复合式和叠合式两种结构形式的真空管道内力分布差异、压差荷载引起的轴力增量及层间接触压力等力学特性,探讨了压差荷载、竖向荷载、结构形式等因素对双层衬砌结构内力的影响规律。结果表明:双层衬砌结构的真空管道在压差荷载作用下对衬砌的弯矩无影响,但会引起轴力增量;当竖向荷载较小时,压差荷载会使真空管道双层衬砌结构产生脱离区,脱离区随着竖向荷载的减小逐渐发展扩大;复合式真空管道的管片、二衬的弯矩量值大于叠合式真空管道;在较大的荷载条件下,复合式真空管道横断面轴力分布不均匀比叠合式真空管道更加凸显。

     

    Abstract: In order to ensure the sealing performance of the evacuated tube transport (ETT) system, a structure combining shield segment and secondary lining was proposed. Based on the numerical simulation model of double-layer lining, taking Shanghai silt clay as the simulated stratum, the internal force distribution of ETT of composite double-layer lining structure and superimposed lining structure is simulated and analyzed respectively. Compared with the internal force of conventional shield tunnel, the ETT internal force distribution difference between composite double-layer lining and superimposed lining structures is analyzed; mechanical properties such as differential pressure load increment caused by axial force and contact pressure between the layers are discussed; the effects of differential pressure load, vertical load, and structural forms on the internal forces of the double-layer lining structure are studied. The results show that the pressure differential load has no effect on the bending moment of the double-layer lined ETT, but it will cause the increment of axial force. When the vertical load is small, the pressure differential load will cause the disconnection zone of the double-layer lining structure of ETT, and the disconnection zone will develop gradually with the decrease of the vertical load. The bending moment value of the segment and second lining of the composite double-layer lining structure ETT is generally larger than that of the superimposed lining structure. Under larger load conditions, the uneven distribution of axial force in the composite cross-section is more prominent than that in the superimposed cross-section.

     

/

返回文章
返回