Estimation of rock mass discontinuity spacing distributions using maximum entropy principle
ZUO Yulong1，2，3，ZHU Hehua2，3，LI Xiaojun2，3
(1. CCCC Highway Consultants Co．，Ltd．，Beijing 100088，China；2. Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education，Tongji University，Shanghai 200092，China；3. Department of Geotechnical Engineering，College of Civil Engineering，Tongji University，Shanghai 200092，China)
The discontinuity spacing is an important parameter to characterize the integrality of rock mass. Due to the complexity of the geological processes leading to the development of rock discontinuities，exponential and lognormal distributions can not adequately describe the discontinuity spacing in the field. With the discontinuity spacing data，the maximum entropy principle is applied by an energy balance to derive the discontinuity spacing distribution，and the obtained maximum entropy distribution is unbiased and consistent. A three dimensional discontinuity network is generated by Monte Carlo simulation. The discontinuity spacings are calculated along 5 different scanlines. The maximum entropy distribution and exponential distribution are used to estimate the discontinuity spacing distributions. Then，K-S tests are used to test the goodness-of-fit to the spacings. The sampling data of discontinuity spacing from Maluanshan tunnel are analysed and estimated by the proposed method. The results show that the maximum entropy distribution exhibits the better performance compared to exponential and lognormal distributions.
左育龙1，2，3，朱合华2，3，李晓军2，3. 最大熵在岩体结构面间距分布估计中的应用研究[J]. 岩石力学与工程学报, 2017, 36(S1): 3492-3498.
ZUO Yulong1，2，3，ZHU Hehua2，3，LI Xiaojun2，3. Estimation of rock mass discontinuity spacing distributions using maximum entropy principle. , 2017, 36(S1): 3492-3498.
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2017, Vol. 36 
