摘要
山岭隧道施工阶段的围岩动态分级以开挖揭露的围岩为评价对象,随着隧道开挖支护循环动态进行。由于隧道施工的时效性,要求围岩分级不仅要合理且其评价指标要取值简便、实施过程快捷。以岩体结构控制论为基础,选取岩块强度、结构面发育特征和岩体结构特征作为基本分级因素,选取地下水、地应力发育状态和不利结构面产状影响作为修正因素;采用Bieniawski模型作为数学模型,并给定各因素权重;用字符RMD表示围岩动态分级各因素的评分,并给出各因素的定性特征和定量指标及其对应的评分区间;总评分采用百分制,并等分为五级,从差到好依次对应Ⅴ级、Ⅳ级、Ⅲ级、Ⅱ级和Ⅰ级围岩。结合河北省境内若干条山岭隧道的2000余幅掌子面的围岩分级实践,将本方法与国标BQ法进行了比较。结果表明:RMD评分与[BQ]值呈线性关系,其分级结果与BQ法有较高的一致性。
The rock mass dynamic classification （RMDC） of mountain tunnel during construction took the tunnel faces excavated by the drill-blast method as the evaluation objectives. RMDC was carried out dynamically with excavation cycles. Its evaluation indexes must be gained conveniently, and the classification process must be rapid, and also the classification results must be rational. The UCS, characters of structural plane and rock mass structure were selected as the basic factors of RMDC. The ground water, crustal stress condition and the occurrence of disadvantageous structural plane were selected as the emendatory factors. The Bieniawski model was used as the mathematical model of RMDC, and the proportion of each factor was determined. The RMD was used in token of rating of every factor of RMDC, and the character and rating of each factor was given. The total rating was in centesimal grades, and was divided to five levels averagely, corresponding to levels Ⅴ,Ⅳ, Ⅲ, Ⅱ and Ⅰ of rock mass from bad to good. Then this method and the BQ method were contrastively ap- plied in 92 road tunnel faces of different highways in the Hebei Province. It is shown that RMD is lineer with [BQ], and also the classification results of this method are much coincident with the BQ method.
出处
《铁道学报》
EI
CAS
CSCD
北大核心
2013年第10期106-113,共8页
Journal of the China Railway Society
基金
国家重点基础研究发展计划(973)项目(2010CB732103)
中航勘察设计研究院有限公司博士后科研基金(2012bsh001)
关键词
隧道工程
山岭隧道
围岩动态分级
施工阶段
tunnel engineering
mountain tunnel
rock mass dynamic classification（RMDC）
construction stage
