Supporting Technology Research in Deep Well Based on Modified Terzaghi Formula

Abstract

In order to solve the difficult problem of supporting roadway with large cross section and broken surrounding rock, the largesection inclined shaft of Pingdingshan Coal Mine is taken as the research instance. In this paper, a modified formula for the Terzaghi ultimate bearing capacity of a foundation is established based on rock mass strength criteria. As per the engineering practice, the maximum roof pressure of the inclined shaft is calculated to be 2.7 MPa, and the minimum pressure value from the modified formula is only 0.3 MPa. In order to control the floor heave of the roadway, a U-type steel inverted arch and bolts support scheme was designed. After calculating through the mechanical model of the inverted arch, its bearing capacity is 0.56 Mpa.rough comparison and analysis of various supporting schemes, finally, the "U-type steel + inverted arch + pouring concrete + backwall grouting" technology is selected, and the engineering practice shows that the supporting scheme can effectively improve surrounding rock stability.

Numerical Simulation of the Supporting Effect of Anchor Rods on Layered and Nonlayered Roof Rocks

“…In particular, the strength, thickness, and relative position of each rock formation in the vertical direction of the roadway roof are different. For example, the direct top rock strata of the Datangtashan Coal Mine and the Huangyanhui Coal Mine are largely single-layered, and the lithology is sandy mudstone with a thickness of 7.5 m or more [27][28][29]. e average thickness of the direct roof rock in Zhuxiangzhuang Coal Mine Roadway is 6.4 m, but the rock stratum contains a large number of bedding and weak surfaces, and considerable roof subsidence can occur [30].…”

Study on Safety Control of Large‐Section Roadway with High Stress and Broken Surrounding Rock

“…Zhang et al [9] supported the concrete-filled steel tube in the high and deep stress roadway. Ping et al [10] and many scholars [11][12][13][14][15] proposed that the main reason of the roadway broken ring is the instability of the structure under high stress, so it is particularly important to improve the stability and bearing capacity of the supporting structure. erefore, on the basis of these methods, taking Gaokeng coal mine in China as the background, the failure mechanism of the subinclined shaft under the mining influence was analyzed in this paper, and the "anchor, mesh, and spray + grouting + full-section anchor cable + floor anchor cable" supporting scheme was put forward.…”

Study on Deformation Mechanism and Supporting Countermeasures of Compound Roofs in Loose and Weak Coal Roadways

“…Zhao et al studied the failure characteristics of the surrounding rock in deep weak and broken roadways, the composite support method of "shotcreting + grouting anchor bolt + anchor bolt + grouting anchor cable + anchor cable" is proposed by the full-section layer-double arch synergy reinforcement technology [21]. Peng et al in order to solve the problem of difficult surrounding rock fragmentation of large-section supporting roadway take the large-section roadway of Pingdingshan Coal Mine as an example, through comparative analysis of various supporting schemes, put forward the "U-type steel + inverted arch + pouring concrete + backwall grouting" support method [22]. Tian and Gao analyzed the stress and displacement characteristics of the surrounding rock of a loose and weak deep well dynamic pressure roadway and established a loose and weak deep well dynamic pressure roadway support model with "multitruss anchor cables" as the main body [23].…”