Design of Evacuation System for High-Rise Building Danqing Yu 11/10/2018

Overview 30-years policy of US codes against use of elevators in fires ~ Attitudinal impediment Focus of current design: number, width and position of stairs ~ Is it adequate? Current use of elevator – Provide emergency use for firefighters and the disabilities Move large number of people from significant height ~ Call for safe and reliable elevator egress system Future trend ~ design elevators with emergency mode ( withstand heat, smoke, water, power-cut) 11/10/2018

Evacuation Plan for High-Rise Building Normal high-rise building Evacuation sequence: emergency floor – upper floors – lower floors Whether or not the elevators attend to disabled population first before they serve others Trained personnel to lead evacuation and good interface design ( switching driving mode for different emergencies) Mega high-rise building Elevators and refuge place are zoned vertically by sections Occupants are regularly trained for evacuation Express emergency shaft transit from refuge place to ground lobby in a non-stop fashion 11/10/2018

Buildings Types Need Emergency Elevators Residential Building Buildings with more than 100 persons per floor and with more than 50 floors Buildings with more than 200 persons per floor and with more than 20 floors Office Building Buildings with more than 50 floors and more than 50 persons per floor For 15-20 floor building, population per floor exceeds 100 11/10/2018

Parameters for Evacuation System Parameters of Building Evacuation Traffic Flow Building population No. of floors: f (1 f  F) Average passenger walking speed: (0.5~0.75m/s) Passenger density during emergency (1 person/0.46m2) Configuration for Evacuation System Proportion of population evacuated by stairs and elevators Width of evacuation doors (> 0.8m) Width and travel distance of stairs Positions of stairs and lobbies Size of the lobbies Emergency elevator configuration (number, safety mode, driving speed, group control logic ) 11/10/2018

Statistical Method Objective: Minimize total passenger evacuation time ~ Time between the beginning of evacuation and the time when the last passenger departs. Min Te, with Te= max (Tstairegress , Televatoregress) Evacuation by stairs Evacuation by elevators ~ Assume elevators are loaded by passengers from one floor Corresponding to different highest reversal floor 11/10/2018

Constraints associated with building traffic flow Space limitation Budget consideration Service quality requirement Normal mode Emergency mode Objective for configuring traffic system Minimize the weighted sum of average waiting time (or total service time) during normal mode and the evacuation time during emergency mode

Safety regulation Emergency mode for elevators Water tolerance parts, Emergency power if main power fails Enclosed lobby on each floor of the building, elevator should be installed in smoke-proof shaft  1 hour fire resistance and pressurized against smoke infiltration. Real time monitoring of elevator system status and any conditions that may threaten its safe operation. Max No. of elevators and stairs The number of floors in each elevator zone  15 ~ 16 floors Layout of elevators and stairs Typical building: 3000 m2 of floor space, 500 m2 core area (including elevator, 2 stairs: 1.2 m each) Stairs are located diagonally across the core area from each other. 11/10/2018