English：

Aiming at the reconstruction of the solid⁃web large slab beam of a project roof, the method ofusing two⁃point synchronous hydraulic unloading single slab beam and four⁃point synchronous hydrauliclifting three slab beams is proposed, and the measures to strengthen the out⁃of⁃plan stability of single slabbeam during unloading are adopted. Under the condition that large cranes cannot be used for hoisting,the problem of dismantling and installing large components in situ by using the original structure issolved. The practice shows that the series of methods are successfully applied in the reconstruction of thelarge slab beam of the project, which provides a solution for the reconstruction of large components in thefield of civil construction.