Rock water interaction on the effect of drying and wetting to the mechanical and dynamic properties of tropical weathered granite

Abstract

This study deals with the effect of water on the tropical weathered granite and sandstone rock characteristics. Water act as an agent in the weathering process that lead to the weakness of the cementation and bonding condition. The process of wetting and drying are able to take place with the presence of water inside the rock microstructure, then further created the numbers of micro-pore which contributing to weakens the rock structure. Thus, this study is focusing to analyses the effect of the presence of water on the mechanical and dynamic properties of granitic rock depending on its weathering degree. The interaction between water and rock was observed through the water-rock interaction test by using saturation and caliper method, where all the rock samples, totalling 81 samples allowed to experience the wet and dry conditions for 21 days, 56 days and 90 days. Uniaxial compressive strength test, indirect (Brazilian) tensile strength and point load tests were conducted to determine the strength of the rock. Meanwhile, P-wave velocity test was conducted to measure the wave velocity that able to penetrate through the intact rock. In conclusion, the increasing of weathering degree, will allowed the rock to absorb the water as their particles has not more tightly bonding. Therefore, it found that the strength of tropical weathered granite was decrease as the interaction with water causes the interlocking of the rock particles is reduces from the process of weathering.