Comparative study of granite in Tung Chung area

Abstract

The strength of rock material depends mainly on the mineral composition and texture. Rock textures were quantified by petrographic image analysis. The texture coefficient TC can calculated based on the measured parameters include grain length along long axis Dmax, grain width along short axis Dmin, perimeter Lp, area A, form factor FF, aspect ratio AR, area weighting AW, number of non-elongated grains N0, number of elongated grains N1 and angle factor for quantify orientation for elongated grains AF. The correlation between the TC and the rock strength was evaluated. The rock strength was obtained by converting the point load strength index into the uniaxial compressive strength. The statistical assessment of the analysis was also conducted to evaluated the reliability of the data and correlations. None of the regression models showed a significant correlation to the rock strength. Limitation on the point load test and mineral assessment played an important role on the contradictory results compare with some previous studies. Limitation on the model is still under investigating by difference authors. This study provides information to build up the statistical data for further analysis.