Paint tin cans.Paint cans,Tin can,Round cans,Triple tight lever can,can for paint Jiangsu Fast Pack Co., Ltd , https://www.fast-metalpack.com
The fact that many lanes are self-stabilizing suggests that the surrounding rock itself has a large self-supporting capacity, and the instability of the surrounding rock is due to this lack of capacity. The so-called support refers to some artificial structures used to help the surrounding rock improve self-supporting ability to avoid the occurrence of damage. If the support is treated as a damage and the support is seen as a system that resists collapse and prevents deformation of the rock mass, the support cost will be multiplied and the reliability will be greatly reduced.
Since the support is to prevent damage to the surrounding rock, the design and construction of the support must be directed against the damage that will occur in the surrounding rock. therefore. Identifying the potential damage patterns and scale of surrounding rock is extremely important.
The empirical and theoretical analysis shows that the failure mode of the surrounding rock of the roadway mainly depends on the burial conditions and mining effects of the roadway, especially the rock mass structure of the surrounding rock, and the rock mass structure depends on the cutting degree and cutting method of the geological discontinuity. . According to the rock mass structure, the failure mode of the roadway can be summarized into several types:
1. Arched slump of loose body
2. Bending and separation of layered rock mass
3. Rock mass collapse in jointed rock mass
4. A large number of deformations of weak rock mass
5. Brittle failure of hard rock mass
6. Impediment damage of the roadway
Roadway failure mode
The destruction of the roadway refers to the gangs, roofs, bottoms, collapses, massive shrinkage and misalignment of the surrounding rock of the roadway. The excavation of the roadway changes the stress state of the surrounding rock and provides free space for this damage to occur. After many roadways are built, they can maintain self-stability without damage for a long time. Other roadways must be artificially supported to maintain stability.