Deterioration law of limestone freeze-thaw cycles

Abstract:

Based on the rock damage theory, the damage deterioration model of rock under the freeze-thaw cycle is derived. The freeze-thaw cycle test method is used to test the physico-mechanical characteristics of the Houwaizi Tunnel limestone rock sample, and analysis is made of its damage deterioration law. The results show that the rock mass and the longitudinal wave velocity of increase first and then decreases with freezing-thawing cycle, the uniaxial compressive strength decreases continuously with freezing-thawing cycle, and the elastic modulus and peak strain increase gradually with freezing-thawing cycle. Through analysis, the relationship between the total damage variable and strain of limestone under the action of freezing-thawing cycle is obtained. The combined action of freezing-thawing and load will aggravate the total damage, the coupling effect will weaken the total damage, and the limestone strain values tend to agree that the number of freeze-thaw cycles is not the main factor affecting the strength limit.