Paper Title
EFFECT OF BRINE SUBMERSION ON MECHANICAL PROPERTIES OF DECORATING STONES

Abstract
Abstract - The objective of this study is to determine the effects of NaCl brine submersion on mechanical properties of siltstone, sandstone and marble that have been used as decorating stones in the northeast of Thailand. Rock specimens are submerged under saturated brine for up to 240 days. Every 60 days interval, their liquid contents, strengths and elasticity are determined. Results indicate that after 240 days siltstone and sandstone specimens can absorb brine up to 6% and 9% by weight, where less than 0.1% can be absorbed by marble. Due to the effect of pore pressure both compressive and tensile strengths and elasticity of the rocks continue to decrease with increasing submersion duration. When left air-dried for 30 days further reduction of rock strengthsand elasticity are observed from the siltstone and sandstone. This is due to initiation and propagation of fissures and micro cracks caused by the growth of remaining salt crystals left in the pore spaces. Keywords - Rock Deterioration, Salt Crystallization, Sodium Chloride Brine, Submerged Duration, Rock Strengths