中国农村水利水电Issue(1)：173-179,7.DOI:10.12396/znsd.2500210
干湿循环作用下卸荷损伤泥岩劣化机理研究
Study on the Deterioration Mechanism of Mudstone Induced by Unloading Damage under Wetting-drying Cycles
摘要
Abstract
The deterioration of mudstone strength in the excavation unloading damage area under the action of wetting-drying cycles is the main cause of slope and foundation instability in mudstone area.Mudstone in Badong area is selected as the research object.Through triaxial loading and unloading test and nuclear magnetic resonance analysis,the evolution law of macro-mechanical properties and micro-pore structure of mudstone damaged by unloading under wetting-drying cycles are studied,and the deterioration mechanism of mudstone damaged by unloading under wetting-drying cycles are revealed.The results indicate that under the influence of wetting-drying cycles,the internal porosity of unloading-damaged rock samples increases,yet the rate of increase progressively diminishes;the impact of wetting-drying cycles on the micromechanical structure of mudstones gradually wanes.During the wetting-drying cycles,the pore distribution within the rock samples exhibits an evolutionary characteristic where small and medium pores gradually transform into larger pores.With the increase in the number of wetting-drying cycles,the strength and elastic modulus of the rock samples gradually decrease,and the cracks gradually increase when the rock samples are damaged,showing significant degradation characteristics.Establishing the relationship between the damage degree of the micromechanical structure of mudstones,the macroscopic mechanical degradation degree,and the number of wetting and drying cycles enables cross-validation and prediction between macroscopic and microscopic parameters.Under unloading conditions,cracks develop within the mudstone,and when water enters the mudstone through these cracks,the clay mineral particles absorb water,leading to swelling and disintegration.The repeated wetting-drying cycles cause damage to the structural system of the mudstone,which is the fundamental reason for the deterioration of its mechanical properties.关键词
干湿循环/卸荷损伤/细观结构损伤度/宏观力学劣化度/劣化机理Key words
wetting-drying cycles/unloading damage/microstructure damage/macroscopic mechanical deterioration/deterioration分类
建筑与水利引用本文复制引用
赵二平,魏宇航,车德龙,蒋尚家,章涵,李建林..干湿循环作用下卸荷损伤泥岩劣化机理研究[J].中国农村水利水电,2026,(1):173-179,7.基金项目
国家自然科学基金资助项目(U2034203,NO.42207218). （U2034203,NO.42207218）
