Deep-buried stope overlying strata type evaluation standard and thin bedrock thickening reconstruction design method

Abstract

The invention discloses a deep-buried stope overlying strata type evaluation standard and a thin bedrock thickening reconstruction design method. The method comprises the following steps: firstly, determining the critical thickness capable of forming a stable stress arch in bedrock based on the stress arch forming principle, and establishing a deep-buried stope overlying strata type evaluation standard, therefore, the blank in the evaluation standard aspect of the overlying strata structure type under the stratum conditions of deep burying, thick unconsolidated strata and obvious change of bed rock thickness is filled up; then, based on the standard, proposing a bedrock thickening and transformation design scheme for the formation conditions of ultrathin bedrock and thin bedrock, wherein the design scheme comprises the length, thickness and the like of a thickening and transformation design area; and finally, providing a thin bed rock thickening transformation design method, proposing a multi-level inclined top smooth grouting scheme and a construction method, designing parameters such as drill hole arrangement and grouting materials, so that active control over stope disasters and accidents can be achieved, and the disasters and accidents caused by passive control measures in the stope in the past are avoided.

Description

technical field [0001] The invention relates to the field of mine pressure and strata control, in particular to the evaluation standard for overlying rock types in deep buried stopes and the design method for thickening and transforming thin bedrock. Background technique [0002] With the large-scale mining in recent decades, the shallow buried coal resources in eastern my country (Shandong, Anhui, Henan, Hebei) are almost exhausted, and mines are mining deep buried coal resources under the conditions of Quaternary thick loose layers and thin bedrock. . On-site geological exploration in the eastern region shows that the thickness of the bedrock overlying the deeply buried coal seam varies greatly. The bedrock thickness in some areas is only a dozen meters thick, and the bedrock thickness in some areas reaches hundreds of meters. The law of mine pressure in the stope and the mine pressure caused by it are very different, and the influence of the stability control of the stope...

AI Technical Summary

Problems solved by technology

The existing stope overburden classification and evaluation system mainly focuses on shallow buried strata conditions (buried depth ≤ 200m), and only uses the three zones of the stope as indicators for classification, and the evaluation method does not consider the formation of stress arches caused by overlying rock movement. and maintain stable mechanical conditions

[0004] (2) As we all know, when the bedrock reaches a certain thickness, the rock formation will form an arch structure during the sinking process, which has a protective effect on the lower stope; when the bedrock thickness is small, such an arch protection structure cannot be formed, resulting in Accidents such as end face caving and chipping

At present, there are no active control measures from the perspective of overburden structural transformation

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