基于掘进性能的TBM施工围岩综合分级方法

A novel classification method of rock mass for TBM tunnel based on penetration performance

传统围岩分级方法侧重于围岩的稳定性,对于TBM施工隧道工程,围岩与TBM均扮演重要角色,有必要建立一套服务于TBM隧道工程的围岩分级新方法。依托引汉济渭引水隧洞工程的现场数据,对场切深指数FPI与地质参数、掘进参数的相关性进行分析,建立TBM隧道的围岩可掘性分级;对影响TBM利用率的主要地质因素进行分析,建立TBM隧道的适应性分级。综合考虑工程的围岩可掘性及TBM适应性,以施工速度为指标,建立基于掘进性能的TBM施工围岩综合分级。分级选取岩石强度、岩体完整性、地下水状态、初始地应力状态、隧道轴线与主要软弱结构面夹角等5方面因素指标,对TBM推力、贯入度、利用率和施工速度进行影响关系综合分析。结果表明,新建立的TBM施工围岩综合分级方法可以进行TBM掘进性能预测与工期、成本分析,有效解决开敞式TBM工程实用围岩分级问题。

The traditional rock mass classification method focuses on the stability of surrounding rock. For TBM tunnel,the machine performance should also be considered in construction. It is necessary to establish a new method of surrounding rock classification for TBM tunnel. Based on the field data of Hanjiang to Weihe River Valley Diversion Project,the correlation among field penetration index（FPI）,geological parameters and tunneling parameters is analyzed. Then the boreability classification of rock mass is established. The main geological factors affecting the machine utilization were analyzed and the adaptability classification of TBM is also established. In order to reflect the TBM performance,the rock mass is finally classified by evaluating the advance rate,which is affected by the boreability of surrounding rock and the adaptability of TBM at the same time. Five factors,including the rock strength,rock mass integrity,groundwater state,in-situ stress state,tunnel axis and weak structure characteristics,were selected in the study and finally to establish the comprehensive classification of rock mass. The results show that the comprehensive classification of rock mass for TBM tunnel can be used to predict the TBM performance,analyze the duration and cost of project,and effectively solve the practical surrounding rock classification problem of open TBM.