%0 Journal Article
%A HOU  Zhao-xu
%A LIU  Xian-feng
%A WANG  Tong
%A ZHANG  Jun
%A YUAN  Sheng-yang
%A HU  Jin-shan
%T Mechanical Characteristics and Damage Constitutive Model of Quartzite under Freeze-thaw Cycles
%D 2025
%R 10.11988/ckyyb.20231018
%J Journal of Changjiang River Scientific Research Institute
%P 177-185
%V 42
%N 1
%X <p id="p00010">There are a large number of rock slopes in the difficult and dangerous mountainous areas of southwest China. Long-term freeze-thaw action deteriorates the mechanical properties of the rock mass, leading to decreased slope stability. To study the damage degradation law of rock mass under freeze-thaw action, uniaxial compression tests were conducted on low-porosity quartzite from a high and steep slope in the southwest hazardous mountainous area. The mechanical deterioration and energy evolution were analyzed. Based on the energy evolution law, a method for determining the complete compaction point of rock was proposed. A piecewise damage constitutive model of the rock in consideration of the compaction section was established by taking the complete compaction point as the piecewise point. Results show that early freeze-thaw cycles have little effect on the quartzite. However, when the number of freeze-thaw cycles exceeds 40, the mechanical properties of quartzite deteriorate significantly, and the failure mode gradually changes from shear failure to a combination of tensile and shear failure. The point corresponding to an elastic energy consumption ratio <i>K</i> (ratio of dissipated energy to elastic energy) of 1.2 is determined as the complete compaction point. The strain corresponding to the complete compaction point increases linearly with the increase in freeze-thaw cycles. The proposed piecewise damage constitutive model matches well with experimental data and more accurately describes the deformation and failure characteristics of freeze-thaw damaged quartzite.</p>
%U http://ckyyb.crsri.cn/EN/10.11988/ckyyb.20231018