Empirical Correlation of Weathering Grade and Rock Properties of Weathered Granitic Rock

Abstract

Rock mass in Malaysia seems to experience high rate of weathering due to its tropical climate. The understanding of weathering process in influencing rock mass behaviour is vital. Previous studies have found that many geotechnical characteristics such as weathering are controlled by the density and arrangement of fractures within the rock, but the relationships between fracture patterns and weathering grades are not typically considered. In this study, weathered granitic rock samples were assessed to determine the correlation of weathered rock characteristics namely mineralogy, weathering grade, joint characteristics with density, UCS and P-wave velocity. The results of the experiment showed that the weathering grade was found to have inverse impacts on all assessed joint characteristics parameters such as joint spacing, joint inclination except for frequency of joint set. Whilst, the rock strength such as R value, UCS and Vp appeared to decrease with increase of weathering grade.