An innovative N00 mining approach for protecting entries and mining panels

Abstract

Addressing the issues of significant entry settlement and severe mining pressure manifestations in the conventional 121 approach, an innovative N00 approach is proposed. By comparing the mining process and entry formation process of different approaches, the characteristics of entry roof settlement evolution under different approaches are obtained. The N00 approach, which incorporates roof cutting and NPR cable support, optimizes the mining and entry formation process to reduce the settlement phase of entry roof, decreases the settlement of entry roof, and enhances the steadiness of entry roof. The N00 approach modifies the entry roof structure through roof cutting and establishes a hydraulic support load mechanics model for the mining panel to derive the theoretical load pressure formula for the N00 approach’s hydraulic support. Compared with the conventional 121 approach, the pressure on the N00 approach’s hydraulic support is reduced. Empirical data obtained through field monitoring demonstrate that the N00 approach has reduced the roof settlement of the entry and weakened the mining pressure manifestation at the mining panel, achieving the goal of protecting the entry and mining panel.

Keywords

N00 approach / entry formation process / roof cutting / roof settlement / mining pressure manifestation

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