螺旋隧道超大管棚预施工支护关键技术研究

Key Technology for Pre-construction Support of Spiral Tunnel Super Large Pipe Shed

近年来,我国在管棚预加固研究方面更是取得了很多显著的成果,这些无可否认。但在目前,管棚预加固理论框架体系依旧十分薄弱,许多比较基础理论研究都没有得到系统的验证,以螺旋隧道超大管棚预施工支护关键技术为例,结合现场施工实际情况,通过对该技术进行分析,主要得到以下研究成果。(1)介绍了螺旋隧道超大管棚预施工工法的设计,分析了管棚的布置形状、几何参数与注浆设计等影响因素。(2)提出了具体的螺旋隧道超大管棚预施工方法,分析了螺旋隧道超大管棚预施工工艺流程。(3)分析了实际工程中存在的问题及解决方法,有效地解决了钻孔孔位偏压、钢管未准确就位,下一循环受侵、注浆效果差等问题。

In recent years, China has achieved many remarkable results in the study of pre-reinforcement of pipe sheds. These are undeniable. However, at present, the theoretical framework system for pipe shed pre-reinforcement is still very weak, and many comparative basic theoretical studies have not been systematically verified. This paper takes the key technology of pre-construction support for spiral tunnel super large pipe shed as an example, combined with the actual situation of site construction, analysis of the technology, the main results are as follows.(1) The design of pre-construction method for spiral tunnel super large pipe shed is introduced. The factors affecting the layout shape, geometric parameters and grouting design of the pipe shed are analyzed.(2) The specific pre-construction method of spiral tunnel super large pipe shed is proposed, and the pre-construction process flow of spiral tunnel super large pipe shed is analyzed.(3) Analyzed the problems and solutions in the actual project, effectively solved the problems of the borehole position bias,the steel pipe not being accurately seated, the next cycle being invaded, and the grouting effect is poor.