Incorporation of elevator evacuation from a specific floor – A numerical study of an office building

This paper investigates evacuation from a specific floor plan to determine if elevators can replace one of the escape routes consisting of a staircase without lengthening the evacuation times. This study specifically studies evacuation from one single office floor with 360 and 540 occupants, designed as one fire compartment with an area of 2800 m2. To specify the occupants’ willingness to use the elevator for evacuation from different floors, three different functions are used. These functions are modified to include more floors and are used to derive different distributions for the proportion using staircases and elevators, by simulations in Pathfinder. Two setups are studied. First, three staircases are used for evacuation. Secondly, one staircase is replaced with five evacuation elevators with capacity for eight occupants, and one elevator for sixteen occupants. For these setups, evacuation is studied from the 2nd, 8th, 16th, 25th and 50th floor. In addition to the studied functions, distributions that minimize the evacuation time for each floor are derived from the simulations. These distributions give the shortest possible evacuation times. The distributions are then compared to evacuation simulations from the first setup, only utilizing the three staircases. The results show that for the elevators to fully replace a staircase, between 45-60 % of the floor occupants need to use the elevators when the occupant count is 360, and 43-50 % when the number of occupants is 540. However, these values are dependent on floor number. Compared to the functions studied, the optimal percentage is significantly higher for lower floors, becoming closer to the functions as they increase with higher floor numbers. For each distribution on every floor, queuing time was also studied. Based on the results from the calculations, the study concludes that six evacuation elevators could replace one staircase on the studied office floor. However, this result relies on a certain percentage of the occupants using elevators for evacuation.

Numerical studies on fire hazards of elevator evacuation in supertall buildings

Long evacuation time is a key fire safety concern for crowded supertall buildings. Elevator evacuation appears to be the only choice but fire safety provisions are not specially designed for the use of elevators. A fire safe elevator system was proposed earlier for supertall buildings by providing elevator accessible on each floor level and passing through the refuge place. The fire hazard associated with this design has been studied numerically through an example building in this paper. Smoke spread to the elevator system was considered in the study. The effect of ventilation of the shaft, stack effect and wind effect on smoke movement were studied by empirical equations in fire engineering and justified by computational fluid dynamics. Different designs of smoke extraction with pressurization system were evaluated by analysing the smoke dispersion and pressure distributions. The effect of fire at different heights on smoke spread was also investigated. Results show that the smoke extraction system can only delay smoke spread to the elevator shaft near the fire source for a short time. The “four-floor approach” pressurization system can confine the smoke in the area of fire floor for a sufficiently long time period for safe evacuation.

Experimental Study on Evacuation Process Considering Social Relation in a Tall Building

Elevator evacuation has been considered in high-rise building evacuation in the world, especially in China. Elevator safety has been widely studied for this purpose and technical standards are also available in different countries. However, it is critical to understand human behaviors in elevator evacuation before elevators can be used in building evacuation. It is expected that social relation (family, friend, classmate, etc.) will play an important role on evacuation behaviors. However, researches are largely missing on social relation and its impacts on movement and behaviors of the evacuees. This paper aims to investigate the crowd evacuation considering social relation. An evacuation experiment is conducted in a 11-storey office building. Participants who take part in the experiment include individuals, families and lovers. Evacuation behaviors especially decision-making as well as important factors affecting evacuees’ choices are discussed. Movement characteristics of evacuees in the stair are also analyzed. It is concluded that family members will take actions, such as take elevators or stairs, together. Females and evacuees in poor condition prefer to take the elevator during evacuation. Many pairs or small groups may be formed owing to social relations. The groups take more time to make decision. The members in small groups may block the traffic and slow down the speed of the crowd. Evacuation efficiency changes greatly considering small group behaviors and social relations. Experimental results are helpful for determining the effective rules and regulations in elevator evacuation in high-rise buildings.

Design Concept for Evacuation Warning System of Elevator in Fire

This paper presents the input and output of elevator evacuation warning system based on the analysis of elevator evacuation risk in fire, and expounds elevator evacuation warning system design concept from three aspects, which are "use of the elevator is safe", " waiting for the elevator is safe" and "elevator's decision is a safe choice".

Study on Necessity and Safety Measures of Elevator Evacuation during High-Rise Building Fire

Elevators are increasingly widely used in high-rise buildings. Because of its fast running, elevators, with great potential value and social requirements, are now days becoming very important traffic tools in high-rise buildings. However, it is an urgent problem to evacuate safely by using elevators during high-rise building fire accidents. This paper elaborates the necessity of elevator evacuation, analyzed the problem of evacuation by general passenger elevators. Some useful measures are put forward, such as fire prevention, smoke-proof, water-proof and emergency power supply for elevator evacuation during high-rise building fires. It is of great importance for us to utilize these measures for the evacuation by elevators during high-rise building fire accidents.