Study on Estimation Method of Rock Mass Discontinuity Shear Strength Based on Three- Dimensional Laser Scanning and Image Technique

• Published in: Journal of earth science (Wuhan, China) Vol. 23; no. 6; pp. 908 - 913
• Main Author: 唐辉明 葛云峰 王亮清 苑谊 黄磊 孙淼军
• Format: Journal Article
• Language: English
• Published: China University of Geosciences China University of Geosciences 01.12.2012; Springer Nature B.V
• Subjects: Biogeosciences; Discontinuity; Earth and Environmental Science; Earth science; Earth Sciences; Estimating techniques; Geochemistry; Geology; Geotechnical Engineering & Applied Earth Sciences; Laboratory tests; Lasers; Light sources; Mathematical models; Rock; Rocks; Scanning; Shadows; Shear strength; Shear stress; Stresses; Three dimensional imaging; 三维激光扫描; 图像技术; 实验室测试; 岩体结构面; 强度估算; 抗剪强度; 直接剪切试验; 表面粗糙度; China; rock mass discontinuity; shear strength; rock mechanics; image recognition technique; estimation method; three-dimensional laser scanning technique
• ISSN: 1674-487X; 1867-111X
• DOI: 10.1007/s12583-012-0301-2

The estimation of shear strength of rock mass discontinuity is always a focal, but difficult, problem in the field of geotechnical engineering. Considering the disadvantages and limitation of exist- ing estimation methods, a new approach based on the shadow area percentage （SAP） that can be used to quantify surface roughness is proposed in this article. Firstly, by the help of laser scanning technique, the three-dimensional model of the surface of rock discontinuity was established. Secondly, a light source was simulated, and there would be some shadows produced on the model surface. Thirdly, to obtain the value of SAP of each specimen, the shadow detection technique was introduced for use. Fourthly, compared with the result from direct shear testing and based on statistics, an empirical for- mula was found among SAP, normal stress, and shear strength. Data of Yujian （~ River were used as an example, and the following conclusions have been made. （1） In the case of equal normal stress, the peak shear stress is positively proportional to the SAP. （2） The formula for estimating was derived, and the predictions of peak-shear strength made with this equation well agreed with the experimental re- suits obtained in laboratory tests.