Performance-based fire safety design for automated vehicle parking steel structures

Abstract

Automatic car parking systems, developed to save space and volume in car parks, have become high-capacity car park structures over time. Tower-type automated car parks are prefabricated steel structures included in this class. These structures, which are basically composed of a car lift and slots that parking pallets carrying cars are seated on, have many knowledge gaps regarding fire safety. The effects of vehicle fires and fire spreading mechanism between cars are not known in tower-type automated vehicle parking structures. The design criteria of sprinkler systems to be used in these structures are a matter of debate. The purpose of this thesis is to enable the emergence of accessible and applicable designs by understanding horizontal and vertical fire spreading mechanisms between passenger cars and the structural fire response of tower-type automated vehicle parking structures. There is no automated car park fire or fire test for this kind of structure that has been reported in the world yet. For this reason, studies were carried out through fire simulations and finite element analysis in this thesis. The thermal conditions and times required for the fire in a car to spread to the cars at the side and upper parking pallet were determined by fire simulations. Then, the fire-induced collapse mechanism of the parking pallets was analytically modeled. Current parking pallet – pallet rail design modified to prevent pallet dislodgement. Finally, the behavior of the steel structure under a fire was analyzed by the finite element method, and a design was proposed in which a partial collapse would not occur in the structure and parking pallets as a result of a fire. These studies have been used as analysis tools in the implementation of the three-stepped fire safety doctrine for automated vehicle parking structures. The doctrine steps are respectively preventing the fire spreading from vehicle to vehicle, collapse/dislodgement of parking pallets and partial collapse at the main structure. At the end of the study, different design proposals with and without a sprinkler system were defined by using iterative methods.