Cost-oriented fire safety design of urban structures

Providing adequate fire safety for urban buildings is a life-saving goal, which can be addressed from different perspectives. There are rare studies integrating fire and life-cycle cost (LCC) of conventional urban structures. To address this, a cost-performance framework is developed here. Two four- and seven-story steel and RC structures are designed first for conventional loads and then are fireproofed to meet their required fire-resistance rating. A range of sprinklers from 3200 mm, based on NFPA 13, to 12000 mm is configured. The fires are simulated using an FDS tool, and the results are employed to monitor the evacuation plans and the structural responses. The steel structures are additionally analyzed under the assumption that they are not fireproofed. The human and financial damage costs are next estimated and the LCC for every case/scenario is determined. Results show that, interestingly, the optimum LCC does not belong to the designed cases based on NFPA 13; rather the sprinkler spacing of 6000 mm meets an optimum LCC. It is also shown that steel structures without fireproofing do not have a higher LCC if the sprinklers are placed over a shorter distance. The latter result can particularly be beneficial for non-fireproofed constructed buildings.