Physical and Mechanical Properties of Marble under the Combined Effects of Chemical Solutions and Freeze-Thaw Cycles

Because of the increasingly common use of rocks in engineering projects in cold regions, an understanding of the degradation of rocks during freeze-thaw cycles has become especially important. Because the water in contact with rocks is often contaminated with pollutants that are either acidic or basic, it is also important to determine the effects of the freeze-thaw cycles on rocks when they come in contact with acids and bases. Uniaxial and triaxial compression tests were conducted on marble specimens under the combined effect of water chemical corrosion and freeze-thaw cycles. The variation of mechanical properties of marble specimens was analyzed under uniaxial and triaxial compression. A damage variable based on the porosity of marble was found to determine quantitatively the chemical corrosion and freeze-thaw damage degrees of marble specimens. Test results showed that for different chemical solutions (distilled water, sulfuric acid solution, and sodium hydroxide solution) and with increasing freeze-thaw cycles, the deterioration of the physical and mechanical parameters of marble specimens aggravated gradually. Moreover, the peak strength and elasticity modulus of marble specimens decreased exponentially, but the peak strain increased linearly. The acidic sulfuric acid solution accelerated the degradation of the marble specimens compared to water alone, but the basic sodium hydroxide solution slowed the freeze-thaw damage of the marble specimens compared to pure water. When the number of freeze-thaw cycles exceeded 50, this inhibition effect no longer existed. The damage degradation of rock produced by water chemical solutions, together with the freeze-thawing cycles, simultaneously affects the damage deterioration degree of marble.