Evaluation of physical and mechanical properties of intact sandstones through the Analytic Hierarchy Process (AHP)

Abstract

One of the most significant factors affecting the strength and deformation of intact rocks is weathering, which drastically reduces the rocks’ properties. This study used the Analytical Hierarchy Process model to assess the ranking of strength and physical nature of intact sandstone samples from various locations. The AHP analyses considered fine-grained sandstones, four evaluation criteria, and five different Malaysian locations. When the weathering grade decreases, the strength of the rock increases. Weathering causes decrease in dry unit weight and an increase in porosity. The porosity of weak rock materials influences their strength. The effect is more obvious in grade IV materials, where dry and wet conditions can significantly impair rock strength. According to the AHP analysis results, those diverse sites have distinct attributes in terms of numerous evaluation criteria, depending on the location and its geological features. Based on the general evaluation points in this study, Puncak Perdana were found to have the highest rock strength, whereas Kempas presented the lowest rock strength in general. In addition, Beris Dam, Bukit Indah to Mersing, and Desa Tebrau could be declared as second, third and fourth, respectively, in presenting the rock strength quality of various sandstones samples.