Probability-Based City-Scale Risk Assessment of Passengers Trapped in Elevators under Earthquakes

Abstract

An accurate prediction of the number of passengers trapped in elevators under earthquakes in urban areas is essential for promoting earthquake emergencies. A probability-based city-scale method for assessing the earthquake-induced risk of passenger entrapment in elevators was proposed, in which city-scale time history analysis was performed to simulate the seismic response of building clusters, and the Monte Carlo simulation was conducted to consider the uncertainty of multiple factors, including the mechanical properties of buildings and elevators, the elevator story position, and the spatiotemporal nature of elevator traffics. A case study of the Tsinghua University campus was performed to demonstrate the practicability of the method. The results show that the number of trapped passengers when an earthquake occurs during the off-peak hours of elevator traffic is approximately a quarter of that when the earthquake occurs at 8:00. The maximum number of trapped passengers under the maximum considered earthquake reaches 195, approximately five times that under the design basis earthquake. This study fills a gap in the research on city-scale earthquake-induced passenger entrapment risk. The proposed method can be used to perform both scenario- and intensity-based assessments, thereby having the potential to facilitate virtual rescuer drills and earthquake emergency plans.

Urban risk assessment model to quantify earthquake‐induced elevator passenger entrapment with population heatmap

“…In the comparative study, various sets of representative buildings (i.e., Sets 1, 2, and 3 in Table 2) were selected, and the PTE numbers under the MCE-level earthquake were correspondingly quantified. It can be found that the mean standard deviation of three sets reaches 12.8 when the method proposed in Gu et al (2023) is adopted while that decreases to 4.0 when the population heatmap is utilized to quantify the popularities of buildings in this study, demonstrating that Gu et al (2023) is significantly sensitive to the selection of representative buildings while the population heatmap-powered method in this study is robust. In Gu et al (2023), it was assumed that buildings with the same occupancy featured the same elevator traffic density.…”

“…It can be found that the mean standard deviation of three sets reaches 12.8 when the method proposed in Gu et al (2023) is adopted while that decreases to 4.0 when the population heatmap is utilized to quantify the popularities of buildings in this study, demonstrating that Gu et al (2023) is significantly sensitive to the selection of representative buildings while the population heatmap-powered method in this study is robust. In Gu et al (2023), it was assumed that buildings with the same occupancy featured the same elevator traffic density. This assumption ignores the significant variations between the population densities within different areas.…”

“…To further highlight the importance of population data, a comparative study between this study and Gu et al. (2023) was conducted. In the comparative study, various sets of representative buildings (i.e., Sets 1, 2, and 3 in Table 2) were selected, and the PTE numbers under the MCE‐level earthquake were correspondingly quantified.…”

“…In Gu et al. (2023), it was assumed that buildings with the same occupancy featured the same elevator traffic density. This assumption ignores the significant variations between the population densities within different areas.…”

Minimizing Energy Usage and Makespan of Elevator Operation in Rush Hour Using Multi-Objective Variable Neighborhood Strategy Adaptive Search with a Mobile Application

“…The most recently published articles from the year 2023 presented five studies related to engineering and transportation [39][40][41][42][43]. Shi and Zhu [39] proposed a dual-phase control strategy for cargo transportation using a partial space elevator, which effectively balances multiple control objectives and achieves a stable equilibrium state.…”