The Change Law of Strength of Silty Mudrock Mass under Hygrothermal Conditions Based on Hoek-Brown Criterion

Abstract

In order to study on the impact of hygrothermal condition on strength of silty mudrock mass, a series of uniaxial mechanical tests were carried out. According to the result of these tests, strength parameters of silty mudrock mass were figured out based on Hoek-Brown criterion, and the change law of strength parameters were analyzed. The results indicates when under hygrothermal condition, cohesion, internal friction angle and elastic modulus of silty mudrock mass decrease with the increase of temperature difference, decrease with the increase of soaked time; the reduction of those strength parameters were dramatically as the rock soaked water no more than 2 days, and will tend to be gentle as the rock soaked water more than 2 days; while the reduction of cohesion or elastic modulus was either greater than it of internal friction angle.