Date of Graduation
2003
Document Type
Dissertation/Thesis
Abstract
Pre-driven longwall recovery rooms can be used to safely recover longwall equipment from the current coal panel. The entry is developed and supported ahead of time so that the required combinations of standing and internal supports can be installed before the longwall face approaches. The combination of the internal bolting system and the standing concrete supports are critical for the successful and safe extraction of the longwall equipment. A combined support system that is too soft or too stiff can result in excessive recovery room closures or brittle failures of the concrete crib systems. Three-Dimensional finite element models, combined with an underground test area, provided the critical components and design principles evaluated in a parametric study. The design methodology was evaluated by examining a case study with the prescribed design technique. Crib support stiffness and bolt length proved to be the critical support parameters needed to achieve room stability. Vertical, horizontal, and shear stresses concentrated on the outby abutment pillar corner resulted in plastic deformations above the primary roof support anchorage level. Cable supports installed over the pillar can help stabilize the zone, however, standing supports are required in most sedimentary roof conditions to increase stability and ensure a safe longwall extraction.
Recommended Citation
Tadolini, Stephen Cesare, "Ground control support consideration for pre-driven longwall recovery rooms." (2003). Graduate Theses, Dissertations, and Problem Reports. 9871.
https://researchrepository.wvu.edu/etd/9871