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

2. 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

3. 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

4. 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 floor building, population per floor exceeds 100
11/10/2018

5. 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

6. 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

7. 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

8. 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