Planning of Intermediate Refuge Floors as a Comprehensive Measure for Business Continuity Planning of After Large Earthquakes and Mitigation of Fire Damage on Super High-Rise Buildings

Abstract

Many super high-rise buildings are rapidly constructed in the urban area of Japan and Asia. The population and business activities of super high-rise office buildings are almost the same scale that of a city. If those businesses cannot continue after a big earthquake, huge economic loss and decrease of city function are expected. Therefore, the planning for business continuity after earthquake is strongly required. In addition, super high-rise buildings also have problems fire safety, and it becomes a large problem, especially after earthquake fire safety. To solve both problems, we proposed a comprehensive measure using intermediate refuge floors and its effect of vertical zoning. For business continuity, intermediate refuge floors are used as temporary refuge space for the occupants who cannot stay at their office area because of scattering of fixture, falling of ceilings and water leakage, and business facilities such as electricity and information facilities are divided by the intermediate refuge floors to limit the earthquake damage. As for fire safety, fire prevention equipment such as sprinklers, fire doors, fire shutters, and smoke exhaustion may be damaged by heavy shakiness. Therefore, we expect an intermediate refuge floor as a stable fire and smoke spread prevention measure. Through probabilistic analysis of 100 story model office building, we proposed effective installation measures that intermediate refuge floors are installed primary considering the fire and smoke spread control, and necessary business continuity performance is reinforced by earthquake damage management policy like reinforcing structure, steadily fixing office fixtures, and using flexible sprinkler pipes.