Abstract: In order to explore transfer bearing mechanism of thick composite roof in gob-side entry retaining, combining with characteristics that the composite roof is soft and proteiform and which leads to roof caving in gob-side backfill zone and roof cutting inside entry, systematic stiffness equation of roof, wall and floor is acquired through establishing mechanical model of supporting system beside entry, absorbing deformation characteristics are finally expounded. Roadway-side support system consists of direct roof, wall and direct floor, which bears the roof pressure integrally. The systematic stiffness is increasing with the rising of the stiffness of roof and floor; the rising effect is apparent when the original stiffness is low, in particular. The thick composite roof has a good performance on absorbing deformation, which is beneficial to relieving the pressure of roadway-side wall. For enhancing systematic stiffness of god-side support and strengthening transfer bearing ability of thick composite roof, the integral reinforcing technology is put forward. The research results have been applied to the condition of 10 meters composite roof successfully.

Key words: composite roof, transfer bearing, systematic stiffness, deformation absorption, gob-side entry retaining