Study on a new equation for calculating JRC based on fine digitization of standard profiles proposed by Barton
LI Rui1，2，XIAO Weimin1，2
(1. School of Civil Engineering，Sichuan Agricultural University，Dujiangyan，Sichuan 611830，China；2. Sichuan Higher Education Engineering Research Center for Disaster Prevention and Mitigation of Village Construction，Dujiangyan，Sichuan 611830，China)
Takingten standard joint profiles proposed by Bartonas an object，professional image processing softwares PHOTOSHOP and MATLAB were firstly used to digitize the image of ten standard JRC profiles by removing stray dots located close to the profiles and interpolating pixels between discontinuities in the profiles，then accurate coordinates data of ten standard joint profiles were obtained. On this basis，the root mean square of slope Z2 and amplitude parameter hA of the standard profileswere calculatedat different sampling intervals，and anew empirical equation between JRC and Z2 and hAwas established. Then the new equation，as well as other commonly-used empirical equations，were employed to calculate the JRC values of ten standard profiles and some natural rock joint profiles. The predictions of JRC were compared with the back-analysis values from shear tests，from which it can be concluded that the prediction accuracy of the new empirical equation is greater than that of the former empirical equations，and it has a good prospect in engineering applications.
李 锐1，2，肖维民1，2. 基于Barton标准剖面线精细数字化处理的岩石节理JRC计算新公式研究[J]. 岩石力学与工程学报, 2018, 37(S1): 3515-3522.
LI Rui1，2，XIAO Weimin1，2. Study on a new equation for calculating JRC based on fine digitization of standard profiles proposed by Barton. , 2018, 37(S1): 3515-3522.
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2018, Vol. 37 
