Factors that affect the stability of roads around rocks

Abstract

The control method of deformation of large sections of soft rock formations in coal mines is a major problem in mining practice. Taking Wangzhuang Coal Mine in Shanxi Province, China, for example, the support method of large sections of soft rock formations was studied to control the deformation of the top and bottom plates and two gangs, and to obtain the damage of the surrounding rocks at different depths through drilling imaging. In addition, the displacement, plastic area and stress field distribution patterns of surrounding rocks are obtained by simulating in FLAC3D. Coupling support for broken, plastic and elastic zones is achieved using bolts, grout anchors, and long anchor cables. The bottom of the road is effectively controlled by floor grout and concrete reverse arches. The results show that under the combination of anchorage and grout, the fault depth and degree of the surrounding rocks are less than the original support method, which can effectively reduce the subsidon of the roof and the deformation of the two gangs. It is important to note that anchorage cable set support can effectively reduce shear fault areas in floor and two gang plastic areas, and reduce the weight of the pavement floor. This study provides a technical reference for the support of large sections of soft rock roadways in coal mines.

Towards Long-Term Monitoring of the Structural Health of Deep Rock Tunnels with Remote Sensing Techniques

“…The plastic zone can generally be thought of as the EDZ [66]. For circular tunnels, the radius of the plastic zone is generally calculated on the basis of support conditions, crustal stress and mechanical properties of rocks as follows [67]:…”

An Insight from Rock Bolts and Potential Factors Influencing Their Durability and the Long-Term Stability of Deep Rock Tunnels

“…The properties and application of the grout material are of tremendous importance in ensuring the long-term performance of rock bolts. Indeed, the damaged zones of the surrounding rocks can become plastic and can thus better adapt to the strong deformations thanks to the grouting [122]. However, the grouting should be as appropriate as possible.…”

“…It is widely believed that in the For its part, the grouting material which acts as an intermediary between bolts and rocks [121], must also be correctly selected and installed. In deep excavations where large deformations are frequent, rock bolts cannot be effective without grouting [108,122]. The properties and application of the grout material are of tremendous importance in ensuring the long-term performance of rock bolts.…”

“…In fact, the performance of the anchoring system is influenced by the anchoring length which should be estimated carefully. Moreover, rock bolts can perform their roles properly when they have a reliable anchoring system which can be improved by adequate grouting [106,122]. A lack of anchoring length can result in loss of fasteners and can then lead to anchor bolt failure [117].…”