挤压性围岩大变形危险性评价的组合赋权-理想点模型  

Combination weight and ideal point method model for risk evaluation on squeezing large deformation

作　　者：周航 陈仕阔 刘彤 李涵睿 ZHOU Hang;CHEN Shikuo;LIU Tong;LI Hanrui(Faculty of Geosciences and Environmental Engineering,Southwest Jiaotong University,Chengdu 611756,China)

机构地区：[1]西南交通大学地球科学与环境工程学院,四川成都611756

出　　处：《中南大学学报（自然科学版）》2021年第10期3647-3658,共12页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(41672295);四川省科技厅面上项目(17YYJC0799);中铁二院科研项目(KYY2020122(20-22))。

摘　　要：通过研究分析国内11条隧道65段挤压性大变形案例的发生规律,并考虑到艰险山区地质条件的复杂性及评价指标的全面性,选取围岩洞壁最大主应力、岩石抗压强度、围岩强度应力比、岩石弹性模量、围岩级别、地质构造和地下水构建评价指标体系。由于影响围岩大变形的因素众多,且特定工程地质条件下各指标差异性较大,权重影响相对离散,通过引入距离函数判别法,结合层次分析法和熵权法建立组合赋权规则,综合确定各个指标的权重系数。基于理想点法的计算规则及理论,构建一种挤压性围岩大变形预测模型,最后利用该模型对相关隧道的大变形案例进行工程实例验证。研究结果表明:采用欧氏距离函数进行大变形危险性评价的准确率达到90.9%,说明该模型具有较高可靠性和准确性。Based on the comprehensive analysis of the key factors influencing large deformation, the occurrence rules of 65 sections squeezing large deformation cases about 11 tunnels engineering in China were quantitatively studied and analyzed. Considering the complexity of geological conditions in difficult mountainous areas and the comprehensiveness of evaluation indexes, seven factors were selected as the final evaluation indexes, including the maximum principal stress of the cavern, compressive strength of rock, strength to stress ratio of surrounding rock,elastic modulus of rock, surrounding rock classification, geological structure and groundwater. Because the occurrence of large deformation was influenced by a lot of factors, the weight of each factor varied greatly. By introducing distance function, a combination weights rule was constructed, and the weight coefficients of each index were comprehensively determined with the combined analytic hierarchy process(AHP) and information entropy weight method(EWM). Then, the ideal point method was used to calculate the offset distance between each evaluation value and the ideal point value, and a large deformation prediction model in deep lying and long tunnel engineering was proposed and applied to some statistical cases. The results show that 90.9% accuracy is obtained by calculating with Euclidean distance function, and thus the feasibility and accuracy of the model are verified.

关 键 词：深埋长大隧道 挤压性大变形 危险性评价 理想点法 组合赋权 

分 类 号：TU45[建筑科学—岩土工程]