大跨度小净距黄土隧道关键支护参数研究

Research on the Key Parameters of the Large Span and Small Distance Loess Tunnel

依托河南省武西高速公路桃花峪隧道工程,采用数值模拟手段对黄土地区修建大跨度小净距黄土隧道的关键支护参数进行了分析研究,计算结果及工程实践表明,黄土地区修建超大断面小净距公路隧道以"强支护、早封闭"为基本原则是合理的;通过选用大型号格栅拱架、增大喷射混凝土厚度的方法提高初期支护强度,取消系统锚杆以争取支护时机实现早封闭,设置锁脚锚管以控制围岩整体沉降的措施是可行的。

Based on Taohuayu Tunnel on the Wuzhi-Xixia Expressway in Henan Province, by numerical simulation method, key branch support parameters for tunnels with large span small spacing in loess area are analyzed and studied, calculation results and engineering practice show that： in loess area construction of large section and small spacing of highway tunnel with ＂ strong branch support, early closure＂ as the basic principle is reasonable; through the use of large number of lattice girder, increasing injection thickness of concrete method can improve the early strength of support, the abolition of anchor system for supporting the opportunity can achieve the closed early, set the lock pin anchor tube to control measures for settlement of the whole of the surrounding rock is feasible.