基于结构面网络模拟的岩体深部卸荷裂隙及非均质特性研究

DEEP UNLOADING FISSURE AND NON-HOMOGENEITY OF ROCK MASS USING ROCK DISCONTINUITY NETWORK SIMULATION

深部卸荷裂隙是一类非构造成因的特殊地质现象,常出现在高山峡谷地带,对工程建设有重要影响。将二维结构面网络模拟运用于模拟某水电站边坡平硐内深部卸荷裂隙和常规卸荷裂隙,在该模拟结果中布设18个虚拟钻孔,利用Autolisp编写岩石质量指标统计程序来计算岩体RQD值。并统计、对比两类裂隙岩体在不同阈值的岩体RQD值及其标准差。利用RQD值的差异将两类岩体裂隙实现区分,同时基于RQD值的标准差体现出的数据的离散性,进一步分析裂隙岩体的非均质特性。

The deep unloading fissure is a non-tectogenetic geological phenomenon in the high mountain and canyon areas. This special phenomenon has an important influence on the engineering construction. This paper surveys the characteristics of both conventional and deep unloading fissures in an adit at a hydroelectric power station. The fissures are simulated by rock discontinuity network simulation. Then a statistical code is implemented into Autolisp based on definition of RQD, and used to calculate the rock quality indices. The results of these analyses are used to detect the rock RQD value and its discrete standard under the different thresholds. Through the differences of RQD values, the type of unloading fissures can be identified. Furthermore, non-homogeneous characteristic of cracked rock mass is performed according to the dispersion of RQD values discrete standard.