Full
Outline
The engineering stability of jointed rock masses in cold regions is often affected by freeze-thaw cycles damage, which leads to geological hazards. The core control factor is the deterioration of shear strength of rock mass. In response to the engineering background of the coupled effects of freeze-thaw cycles and shear loads faced by jointed rock masses in cold regions, existing methods for calculating the shear strength of freeze-thaw joints have certain deviations. Therefore, a modified shear strength criterion was proposed that accounts for the strength degradation of jointed rock mass under freeze-thaw cycles. A systematic experimental study on freeze-thaw-shear coupling was conducted using similar material simulation methods. Based on direct shear test results of freeze-thaw joints, the degradation mechanism of rock bridges under freeze-thaw-shear coupling action was revealed as follows. The shear strength of non-persistent jointed rock mass consists of three components, including the shear strength of non-degraded rock bridges, the shear strength of degraded rock bridges, and the shear strength of the joint surfaces. A coupled damage model for rock bridges was established with shear modulus as the variable, achieving quantitative characterization of the degradation behavior of rock bridges. Building upon this foundation, the modified Jennings shear strength criterion demonstrates the following advantages: the mean relative error between theoretical predictions and test results is merely 3.28%, representing a significant improvement in prediction accuracy compared to the original Jennings criterion. This modified criterion effectively captures the strength characteristics of non-persistent jointed rock mass under freeze-thaw action, thereby providing a reliable theoretical basis for studying the freeze-thaw damage mechanisms and safety protection of jointed rock masses in cold regions.
57
29
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |
关闭全屏
No. 86 Xueyuan South Road, Haidian District, Beijing
010-62662699(Operation and Technical Support)
qkjq@cast.org.cn
Copyright © 2025 China Association for Science and Technology. All rights reserved. For all open access content, the relevant licensing terms apply.
Sponsored by the Office of the Leading Group for Cybersecurity and Informatization of CAST, and supported by Science and Technology Review Publishing House
