Predicting the probability distribution of Martian rocks mechanical property based on microscale rock mechanical experiments and accurate grain-based modeling

Abstract

The exploration of Mars would heavily rely on Martian rocks mechanics and engineering technology. As the mechanical property of Martian rocks is uncertain, it is of utmost importance to predict the probability distribution of Martian rocks mechanical property for the success of Mars exploration. In this paper, a fast and accurate probability distribution method for predicting the macroscale elastic modulus of Martian rocks was proposed by integrating the microscale rock mechanical experiments (micro-RME), accurate grain-based modeling (AGBM) and upscaling methods based on reliability principles. Firstly, the microstructure of NWA12564 Martian sample and elastic modulus of each mineral were obtained by micro-RME with TESCAN integrated mineral analyzer (TIMA) and nanoindentation. The best probability distribution function of the minerals was determined by Kolmogorov-Smirnov (K-S) test. Secondly, based on best distribution function of each mineral, the Monte Carlo simulations (MCS) and upscaling methods were implemented to obtain the probability distribution of upscaled elastic modulus. Thirdly, the correlation between the upscaled elastic modulus and macroscale elastic modulus obtained by AGBM was established. The accurate probability distribution of the macroscale elastic modulus was obtained by this correlation relationship. The proposed method can predict the probability distribution of Martian rocks mechanical property with any size and shape samples.