Abstract
The investigation on seismic evaluation of existing reinforced concrete school building made it clear that the earthquake performance in this building is scarce. Therefore, A plan was made to construct the seismic retrofit for this building. In this research, we experimented with joint of the floor slab in an actual reinforced concrete school building to verify the validity of the seismic retrofit. From the test result, Shear strength for joint has been understood and the seismic retrofit construction was executed.