Evaluation of indoor damage in high-rise buildings due to long period ground motion - Seismic behavior of refrigerator considering opening doors and drawers

The aim of this study is to evaluate indoor damage in high-rise residential buildings due to long period ground motion. Enokida et al. (2009) indicates the risk that overturning furniture, such as a cupboard or a refrigerator, would hurt people in a kitchen, so it is important to evaluate the seismic behavior of such furniture. The seismic behavior of simple furniture, such as a cupboard, can be estimated using the previous method, but the seismic behavior of a refrigerator is complex and it is difficult to evaluate it because its doors and drawers would open during floor shaking. In this study the seismic behavior of a refrigerator was evaluated considering opening doors and drawers using shaking table tests and a simulation. First, the shaking table test of a refrigerator was conducted in order to understand the basic characteristics of the seismic behavior of a refrigerator. And the second, the calculation model of the refrigerator was built that can simulate the realistic behavior of the shaking table test. Finally, many cases of simulations were carried out to evaluate the effects of doors and drawers opening or the amount and weight balance of contents in the refrigerator. As the result of this study, the doors and drawers begins to open about 150 cm/s2 in case that contents exist, and the refrigerator begins to move about 250 cm/s2. The moving velocity of the refrigerator is equal to or lower than shaking velocity because the moving velocity is limited by a collision against wall in case that shaking period is 3.0 sec or over. And the refrigerator would collide many times against walls severely with scattering its contents during floor shaking. So it is highly possible that it injures people and blocks evacuation routes.