富水条件下板溪群板岩隧道围岩分级研究  

Surrounding Rock Classification of Banxi Group Slate with Abundant Water

作　　者：吴友银 左清军[1] 闫天玺 WU Youyin;ZUO Qingjun;YAN Tianxi(Hubei Key Laboratory of Disaster Prevention and Mitigation, China Three Gorges University, Yichang 44300)

机构地区：[1]三峡大学防灾减灾湖北省重点实验室,宜昌443002

出　　处：《现代隧道技术》2018年第3期61-68,共8页Modern Tunnelling Technology

基　　金：国家自然科学基金项目(41402259);防灾减灾湖北省重点实验室(三峡大学)开放基金项目(2016KJZ18)

摘　　要：富水板岩隧道围岩泥化、软化问题突出,目前此类隧道的围岩分级是将单轴饱和抗压强度作为分级指标之一。由于板溪群板岩具有特殊的工程地质特性,因此将单轴饱和抗压强度作为板溪群板岩隧道围岩分级指标存在一定的局限性。针对此问题,文章以沪昆客运专线长昆湖南段油坊坪隧道为工程实例,引入软化系数,并将地下水、岩体完整性系数、主要结构面与洞轴交角作为主控因素,建立富水板岩隧道围岩分级体系;基于模糊数学理论,构造各评价指标的隶属函数,利用层次分析法求取指标权重值,并根据最大隶属度原则确定围岩级别。研究结果表明:采用模糊理论对富水板岩隧道进行围岩分级,有效地处理了隧道围岩分级的模糊信息,实现了围岩分级从定性到定量的跨越;引入软化系数通过模糊理论得到的围岩级别与现场实际情况较为接近,说明引入软化系数的富水板岩隧道围岩分级方法具有较强的实用性,可为富水板岩隧道的设计和施工提供参考。For water-rich slate, surrounding rock argillization and softening is a serious problem. At present the uni-axial saturated compressive strength of rock is used as one of the indexes for classification of water-rich slate sur-rounding rock. Since Banxi Group slate has special geological characteristics, the above mentioned grading index isnot completely suitable for its surrounding rock classification due to limitations. For this reason, using the Youfang-ping tunnel at the Changsha to Kunming Section of the Shanghai to Kunming high-speed railway in China as an ex-ample, a softening coefficient is introduced, and the underground water, rock mass integrity coefficient and angle ofthe main structural surface and tunnel axis are regarded as the main controlling factors. A system of surrounding rockclassification for tunnels in water-rich slate is established. Based on the theory of fuzzy mathematics, the member-ship function of each index is structured and the weight of each index is calculated by AHP, and the grade of the sur-rounding rock is determined according to the maximum membership degree principle. The results show that the fuzzyinformation of surrounding rock classification is processed effectively and the classification of surrounding rock isachieved by qualitative analysis to quantitative evaluation by using fuzzy theory. The surrounding rock classificationdetermined by introducing the softening coefficient on the basis of fuzzy theory is close to that determined in practicalapplication, indicating that the practicability of this classification of tunnel surrounding rock in water-rich slate ishigh. This classification system therefore is a reference for the design and construction of tunnels in water-rich slate.

关 键 词：板溪群板岩 隧道 围岩分级 软化系数 权重 层次分析法 

分 类 号：U452.11[建筑科学—桥梁与隧道工程]