The Deformation Characteristics and Lateral Stress of Roadside Crushed Rocks with Different Particles in Non-Pillar Coal Mining

Gob-side entry retaining formed by roof fracturing (GERRF) is a popular non-pillar mining method. The method uses crushed rocks in gob side to support and control the movements of roof. These will deform under pressure generate desirable lateral stress on structures gangue rib. In this study, deformation behavior mudstones with different particle sizes incremental loading was investigated an innovative experimental device that simulated boundary conditions GERRF Influence size generation applied were concurrently observed analyzed. Research outputs from tests showed that: (1) exerted significant influence accumulated axial deformation, period structure rocks. (2) Under same stress, larger size, smaller rock; A skeletal loading-bearing effect apparent rock samples particles (S-2, S-3). compressive process S-2, S-3 divided into structural adjustment, load-bearing crushing cum filling phases. At phase, better resistance stability than other phases; (3) Two types periodic stress-strain curves for tests. “down-concave” type implied primarily consequence compression void spaces. While “upper-convex” curve resulted again; (4) generated large-size small-size samples. Additionally, poor regularity test sample (S-3). relationship between found be approximately linear condition shows good regularity.