摘要
本文针对岩体结构面间距最常见的两种分布形式——负指数分布和对数正态分布,探讨了岩石质量指标(RQD)的Monte-Carlo模拟方法。首先根据结构面间距分布密度函数产生包含50万个随机结构面并按生成顺序排列的模拟真实岩体的总测线,然后为了和实际钻探时以2m测线计算RQD相一致,在总测线上按均匀分布形式随机抽取≥2m的局部测线共5万个计算RQD单值,并进一步统计得出所有RQD的平均值、RQD累积分布曲线及岩石质量描述图。对于自然界大部分岩体,可根据结构面间距统计参数,直接在本文得出的一系列岩石质量图上定出RQD平均值、岩石质量百分比(RQP)及岩石质量风险(RQR)。
A Monte-Carlo simulation method of rock quality designation (RQD) is presented in this paper based on the negative exponential distribution and lognormal distribution for modeling the discontinuity spacings. First of all, 500000 random structure planes were generated based on the negative exponential or lognormal distribution to form a long scan line according to the generation sequence. Subsequently, a series of scan lines, which are about 2 m long in accordance with the practical drilling engineering, were generated based on the uniformly distributed random sampling on the above long scan line and homologous rock quality designations are computed. Meanwhile, the mean value of RQD and cumulative distribution curves of these RQD values were obtained within the same simulation program and the results are plotted. For most rock masses in the nature the mean value of RQD, rock quality percentage (RQP) and rock quality risk (RQR) can be read off from the rock quality description charts plotted in this paper.
出处
《地质论评》
CAS
CSCD
北大核心
2001年第2期146-150,共5页
Geological Review
