Abstract: Roadways are usually constructed in thin bedded coal-rock crossovers and subjected to asymmetric and inhomogeneous damages. Application of conventional unsealing symmetric supporting shows poor performance and worse long-term maintenance effect. Taking the frequent crossover-through roadway construction of Suntuan coal mine as an engineering example, we summarize its typical asymmetric and inhomogeneous damage features, such as shoulder angle fracture, large sidewall deformation, floor heave and whole section instability etc, and analyze its main influential factors. Whole section sealing support was mainly constructed by active support such as anchor, bolt and grouting, assisted by other structure supplement. Inhomogeneous damage of roadways in thin bedded coal-rock crossovers could be controlled by combination of prestress synergy function of anchor and bolt, interaction strengthen of surrounding rocks and grouting, structure supplement of leg-locked equipment and U type shed. Whole section strengthening was implemented through bolt-shed-grouting on roof and sidewall, continuous restraint on arch and bolt-grouting on floor. The technology has been successfully applied in a 570 m deep roadway in coal-rock crossovers, whose deformation was controlled between 180 mm and 220 mm, guaranteeing of construction safety and long-term stability.

Key words: coal-rock crossovers, roadway, inhomogeneous damage, thin bedded rock, sealing supporting structure, support