Downtime estimation of building structures using Fuzzy logic

Residential buildings are usually designed to withstand earthquake damage through their elastic and plastic deformations. The damage causes the buildings to be unoccupiable for a period of time, called the downtime. This paper introduces a methodology to predict the downtime of buildings before the earthquake occurrence through the use of Fuzzy logic. Generally, the downtime can be divided into three main components: downtime due to the actual damage (DT1); downtime caused by rational and irrational delays (DT2); and downtime due to utilities disruption (DT3). DT1 is evaluated by relating the building damageability to given repair times of the building’s components. A rapid visual screening form has been designed to acquire information about the analyzed building. Then, a fuzzy logic is implemented using a hierarchical scheme to determine the building damageability. DT2 and DT3 are estimated using the REDITM Guidelines. The Downtime of the building is finally obtained by combining the three components. The proposed method also allows identifying the downtime corresponding to three different recovery states: re-occupancy; functional recovery; and full recovery