Gong-kuang zidonghua (Dec 2023)
Division of advanced support areas in roadways under dynamic loads
Abstract
The division of advanced support areas and support methods in roadways are key factors affecting the stability of surrounding rock in mining roadways. The existing research mostly divides the advanced support area under static load conditions. Further exploration is needed for the division of advanced support area under dynamic load impact and the relationship between roadway surrounding rock and hydraulic support. Taking the 5304 working face roadway of Zhaolou Coal Mine as the research object, the variation features of working resistance of hydraulic support under dynamic load impact and the relationship between surrounding rock and hydraulic support are analyzed. The concept of dynamic coefficient is proposed. Under the action of dynamic load disturbance, the peak point of advanced support pressure will transfer to the interior of the coal body, resulting in a new plastic zone. Therefore, the area affected by advanced support pressure is divided into fracture zone, plastic zone, elastic zone, original rock stress zone, and newly added plastic zone. According to the coal rock state and dynamic boundary points, the advanced support area is divided into reinforced support section, auxiliary support section, and original support section based on dynamic stress as the boundary. The reinforced support section is composed of fracture zone, plastic zone, and partially elastic zone, and requires high-strength advanced support equipment to strengthen roof support. The auxiliary support section is mainly composed of elastic zones and requires single hydraulic pillars or unit hydraulic supports for auxiliary support. The original support section is located in the original rock stress zone as a whole, and there is no need to strengthen the support. The numerical simulation is used to study the variation law of advanced support pressure under dynamic load, and establish a calculation model for advanced support pressure in roadways under dynamic load. The dynamic stress expression for each support section is derived. The on-site test results show that the support scheme designed based on the division of the advanced support area of the roadway has good support effect and can meet the quality requirements of the advanced support area.
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