Fourier-shape-based reconstruction of rock joint profile with realistic unevenness and waviness features  

考虑真实凹凸度与粗糙度特征的岩石节理轮廓傅里叶形态重构方法（英文）

作　　者：NIE Zhi-hong WANG Xiang HUANG Dong-liang ZHAO Lian-heng 聂志红;王翔;黄栋梁;赵炼恒(School of Civil Engineering,Central South University,Changsha 410075,China;Key Laboratory of Heavy-haul Railway Engineering Structure(Ministry of Education),Central South University,Changsha 410075,China)

机构地区：[1]School of Civil Engineering,Central South University,Changsha 410075,China [2]Key Laboratory of Heavy-haul Railway Engineering Structure(Ministry of Education),Central South University,Changsha 410075,China

出　　处：《Journal of Central South University》2019年第11期3103-3113,共11页中南大学学报（英文版）

基　　金：Projects(51478477,51878668)supported by the National Natural Science Foundation of China;Projects(2014122006,2017-123-033)supported by the Guizhou Provincial Department of Transportation Foundation,China;Project(201722ts200)supported by the Fundamental Research Funds for the Central Universities,China

摘　　要：Rock joint shape characteristics,waviness and unevenness play essential but distinct roles in shear mechanism of rock joints.This study presents a novel method to generate virtual rock joint profiles with realistic waviness and unevenness features.Firstly,joint profiles are obtained by 3D laser scanning device.Secondly,quantification of waviness and unevenness is conducted by traditional method,including digital filtering technique and roughness parameter RL.Thirdly,the discrete Fourier transform(DFT)method is employed to analyze the joint outlines.Two representative Fourier shape descriptors(D3,D8)for characterization of waviness and unevenness are suggested.Then,the inverse discrete Fourier transform(IDFT)is adopted to reconstruct the joint profiles with random values of phase angles but prescribed amplitudes controlled by D3 and D8.The traditional method is then applied to the reconstructed joint profiles to examine statistically the relationships between D3 and D8 and parameters RL of waviness and unevenness,respectively.The results show that larger D8 tends to result in larger waviness while higher D3 tends to increase unevenness.Reference charts for estimation of waviness and unevenness with different pairs of D3 and D8 are also provided to facilitate implementation of random joint reconstruction.岩石节理形态特征,包括凹凸度与粗糙度,是影响岩石节理剪切行为的重要因素.本研究提出了一种新的岩石节理重构方法,该方法能够考虑与真实节理形态相符的凹凸度与粗糙度特征.首先,采用3D镭射激光扫描的方法获取节理的表面轮廓信息.然后,采用传统的凹凸度与粗糙度指标对节理进行形态特征评价.接着,采用傅里叶变换对节理轮廓进行分析,提出了D3与D8两个傅里叶形状指标来分别表征节理的凹凸度与粗糙度.随后,采用傅里叶逆变换,通过设置随机的相位角与调控傅里叶形状指标D3和D8的大小来重构节理轮廓.最后,通过采用传统的凹凸度与粗糙度指标对采用傅里叶方法随机重构的节理轮廓进行分析,研究了傅里叶形状指标D3和D8与传统的凹凸度和粗糙度指标之间的相关性.结果表明随着D3的增大,凹凸度增大;随着D8的增大,粗糙度增大.本文将D3与D8和凹凸度与粗糙度之间的相关关系以云图的形式表示出来,为进一步采用随机轮廓重构方法进行岩石节理数值仿真与力学模拟的相关研究提供了依据.

关 键 词：rock joint profile joint shape analysis discrete Fourier transform joint reconstruction 

分 类 号：TG3[金属学及工艺—金属压力加工]