earticle

영어

Some ceiling systems were damaged by Pohang earthquake so concerns on the seismic performance of them has raised. In this study the shake table test of the ceiling system was conducted to investigate the dynamic behavior and those failure type under earthquake condition. The test specimen was a gypsum panel ceiling system with M-bar type which was used in school building. As the result of the test, minor damage such as falling of single panel around the perimeter and separation from molding was found under domestic design earthquake level. The acceleration response of the ceiling system was amplified over the input acceleration but below 2.5 times. Therefore, it seemed that it was reasonable to use a response amplification factor of 2.5 as the seismic design parameter. Its displacement response was increased as the boundary condition of perimeter was changed by increasing input acceleration. Additionally, the simple spring-mass model of the ceiling system using the lumped mass of the system supported by a hanger and flexure stiffness of the hanger was suggested, and the boundary condition between the panels and the molding part of the ceiling system was assumed as the axial springs. The seismic response analysis was performed to verify the model and to evaluate the seismic demand by the three types of the hanger length. The analysis model could predict properly the displacement response of the specimen when the stiffness of the axial spring was applied to be low. Moreover, analysis results showed that the seismic force and displacement demands affected by the length of the hanger and boundary rigidity, so it needed to be considered for the seismic design of the ceiling system.