Study on the Method of Improving the Fire Resistance Performance of No Threshold Fire Door

In this study, we aim to improve the fire resistance performance by solving structural problem so that gas or flame does not leak through door in case of a while maintaining airtightness and insulation when removing threshold at bottom general door. To along with fire-resistance, an ordinary auto-bottom is provided lower part However, there limit securing fire-resistance. maximize fire-resistance performance, graphite, expandable foaming agent, applied block gap between floor. Additionally, holes induce generated flow into We found blocking plays very important role improving performance.