风化、蚀变对花岗斑岩物理力学特性影响分析

地壳浅表层岩体因受到风化和蚀变作用的影响而导致岩体的孔隙性增加,干密度、抗压强度等物理力学特性降低; 孔隙度作为岩体遭受风化和蚀变作用的重要特征,可以反映出风化和蚀变作用对岩体物理力学特性的影响。因此,可以通过对风化和蚀变花岗斑岩物理力学特性的室内试验,建立孔隙度与其他各项物理力学参数的函数关系,以此分析风化和蚀变对花岗斑岩物理力学特性的影响。研究表明:风化和蚀变花岗斑岩的干密度和抗压强度均随孔隙度的增加而减小,且呈乘幂函数关系,相关系数皆大于0.83; 吸水率与孔隙度则呈二项式函数关系,且随着孔隙度的增加而增加,其相关系数大于0.90; 风化和蚀变都削弱了花岗斑岩的物理力学特性,且随着风化、蚀变程度的增加,花岗斑岩的物理力学特性也呈相应的函数关系降低; 陡倾结构面受风化和蚀变的影响较缓倾结构面强。

INFLUENCE ANALYSIS OF WEATHERING AND ALTERING FOR PHYSICAL AND MECHANICAL CHARACTERISTICS OF GRANITE-PORPHYRY

Porosity is one of the important characteristics of rock mass. It can reflect the effect of weathering and altering for the physical and mechanical characteristics of rock mass. Therefore, the functional relationship of porosity and the other physical and mechanical parameters is established through indoor experiments. The effect of weathering and altering for the physical and mechanical characteristics of granite-porphyry also is analyzed. The results show that the dry density and compressive strength of the weathered and altered granite-porphyry decrease as porosity increases, which presents the power function relationship. Their correlation coefficient are greater than 0.83.The water absorption increases with increasing in porosity, which presents the binomial functional relationship. Their correlation coefficient are greater than 0.90.All the weathering and altering can weaken the physical and mechanical characteristics of granite-porphyry. As increasing in weathering and altering, the physical and mechanical characteristics of granite-porphyry can gradually reduce. The influence of altering and weathering for the steep-inclined structural face is stronger than for the gently dipping structural face.