摘要
准确预测或识别隧道挤压变形对于隧道的设计和施工非常重要.基于案例统计和证据理论,建立了一种新的隧道挤压变形等级预测方法.首先综合考虑隧道挤压变形影响因素,选取强度应力比、隧道埋深、隧道等效直径、支护刚度、岩体质量指标作为挤压变形预测评价指标.然后基于Hoek提出的隧道挤压变形分级方案,建立了隧道挤压变形等级的识别框架.基于挤压变形案例统计和分析,建立了各评价指标的高斯分布隶属度模型,客观地确定各指标的基本概率分配(BPA).最后通过D-S合成公式融合生成的BPA,实现对隧道挤压变形等级的预测.此外,采用准确率和Kappa系数作为模型准确率的评价指标,对国内外139组隧道挤压变形数据进行了验证,准确率和Kappa系数分别为82%和0.77.将该模型应用于木寨岭高速公路隧道的围岩挤压变形预测,预测结果与现场实际条件完全一致,进一步验证了本文模型的准确性和适用性.本文的研究结果有利于提高隧道挤压变形预测的理论水平和可靠性,为类似工程提供参考.
An accurate prediction or identification of tunnel squeezing is extremely important for tunnel design and construction.According to case statistics and evidence theory, a new approach is proposed to predict the tunnel squeezing intensity.The proposed methodology takes five indicators including strength-stress ratio, tunnel burial depth, rock quality index, tunnel diameter and support stiffness as predictive indicators of tunnel squeezing.A framework for identifying the tunnel squeezing intensity is then developed based on the classification scheme proposed by Hoek.At the same time, the Gaussian distribution model is adopted to objectively determine the basic probability assignment of predictive indicators based on case statistics.Finally, the generated BPAs are fused by the D-S synthetic rule to predict the tunnel squeezing intensity.Besides, Accuracy and Kappa coefficient were adopted as evaluation indicators of model performance.A total of 139 cases of tunnel squeezing were used to validate accuracy of the proposed model, the accuracy and Kappa coefficient of prediction results reaches 82% and 0.77.Finally, the established squeezing prediction method is applied to predict the squeezing intensity of Muzhailing highway tunnel, and the prediction results are in full agreement with the actual conditions in the field, further verifying the accuracy and applicability of the model in this paper.The results of this paper can be used to improve the theoretical level and reliability of tunnel squeezing prediction and provide a good reference for similar projects.
作者
焦玉勇
欧光照
王浩
张国华
邹俊鹏
谭飞
张为社
JIAO Yuyong;OU Guangzhao;WANG Hao;ZHANG Guohua;ZOU Junpeng;TAN Fei;ZHANG Weishe(Faculty of Engineering,China University of Geosciences,Wuhan 430074,China;State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan 430071,China)
出处
《应用基础与工程科学学报》
EI
CSCD
北大核心
2021年第5期1156-1170,共15页
Journal of Basic Science and Engineering
基金
国家自然科学基金重点项目(41731284)
国家自然科学基金国际合作项目(41920104007)。
关键词
挤压变形预测
预测指标
案例统计
证据理论
高斯分布
基本概率分配(BPA)
squeezing prediction
predictive indicators
case statistics
evidence theory
gaussian distribution
basic probability assignment(BPA)
作者简介
焦玉勇(1968-),男,博士,教授,博士生导师.E-mail:yyjiao@cug.edu.cn。
