Experimental Investigation on Uniaxial Compressive Strength of Thin Building Sandstone

Thin sandstone is a widely used building material; however, its compressive behavior is not well understood. Four groups of cylinders were manufactured in a factory to investigate the uniaxial compressive behavior of red sandstone. Uniaxial compression tests were performed to determine the compressive behavior and failure mode of the specimens. The geometry of the stress-strain diagram varied among the four groups. The critical strain generally increased with a decrease in the height of the cylinder, whereas the compressive strength exhibited an inverse trend. The experimental diagrams were normalized with the peak stress and corresponding critical strain to represent the stress-strain diagram of each group of cylinders. A formula consisting of two parabolas was employed for regression to obtain a representative mathematical expression of the diagram. The correlations between porosity, compressive strength, and elastic modulus were evaluated based on empirical expressions. Normalized strength was employed to evaluate the size effect on the diameter and length-diameter ratio (L/D) of the cylinder; the latter provided a better prediction of the experimental results than the former. A new expression in terms of L/D was proposed based on the regression analysis of the experimental results. This study is beneficial for the engineering application of sandstone as a construction material.