Lift and Escalators: Basic Principles and Design

MECH3005 – Building
g Services
http://www.hku.hk/bse/mech3005/
Lift and Escalators:
Basic Principles and Design
Dr. Sam C M Hui
Department of Mechanical Engineering
The University of Hong Kong
E-mail:
E
mail: cmhui@hku.hk
cmhui@hku hk
Sep 2010
Contents
• Basic Principles
• Planning & Design Factors
• System Types
Tall buildings are not possible without lifts and escalators
484 m ((2010))
296 m (1993)
Landmark
L
d
k Tower,
T
Yokohama, Japan
(max. lift speed
750 m/min or
12.5 m/s)
367 m (1990)
Bank of China
Building,
Hong Kong
374 m (1992)
Central
C
t l Plaza,
Pl
Hong Kong
415 m (2003)
IInternational
t
ti l
Finance Centre
Two (IFC-2),
Hong Kong
IInternational
t
ti l
Commerce Centre
(ICC),
Hong Kong
Basic Principles
• Terminology
• Lifts [UK] = Elevators [US]
• Escalators (= moving staircases)
• Conveyors (or moving walkways)
Hoists (early form of lift system)
Power elevator (steam)
Basic Principles
• “Escalator”
Escalator = “Elevator”
Elevator + “Scala”
Scala (steps)
• First escalator: designed by Jesse Reno in 1892
Ocean Park (longest outdoor escalator, total 220 m)
Central-Mid-Levels
Escalator, total 790 m
Basic Principles
• Principles of operation
• How Elevators Work
h //
http://www.howstuffworks.com/elevator.htm
h
ff
k
/ l
h
• How Escalators Work
http://www.howstuffworks.com/escalator.htm
* Please find out how they work from these websites.
Power flow through a typical elevator
[Source: How an elevator works
http://web.mit.edu/2.972/www/reports/elevator/elevator.html]
[Source: http://www.howstuffworks.com/]
Planning & Design Factors
• Circulation/Movement of ppeople
p in buildings
g
• Mode (horizontal or vertical)
• Movement
M
t type
t
(natural
( t l or mechanically
h i ll assisted)
i t d)
• Human behaviour (complex, unpredictable)
• Design objectives
•
•
•
•
Free flow of people & goods
Safe operation, comfort & service
Occupy minimum space & require less costs
Aesthetics, disabled access, etc.
Planning & Design Factors
• Circulation elements in buildings include:
•
•
•
•
•
•
•
Corridors
Portals (e.g. entrance, door, gate)
Stairways
Ramps
Lifts
Escalators
Moving walkways
* Try to identify them in a building
Physical or
architectural
elements
Mechanical or
engineering
elements
G/F plan of a commercial building
Can you find
out all the
circulation
elements?
[Source: Hongkong Land]
Planning & Design Factors
• Human factors
• Physical dimensions
• Occupancy ellipse 600 mm by 450 mm (0.21
(0 21 m2)
• Personal space (buffer zone)
• Female: 0.5
0 5 m2 (0.8
(0 8 m diameter circle)
• Male: 0.8 m2 (1.0 m diameter circle)
• Density of occupation
•
•
•
•
•
Desirable: 0.4 person/m2
Comfortable: 1.0
1 0 person/m2
Dense: 2.0 person/m2
‘Crowding’:
Crowding : 3.0
3 0 person/m2
Crowded: 4.0 person/m2
Typical occupancy ellipse (male subject)
[Source: CIBSE Guide D]
Planning & Design Factors
• Human factors
• Interpersonal distances
•
•
•
•
Public distance: > 7.5 m (far); 3.6-7.5 m (near)
Social distance: 2.1-3.6 m (far); 1.2-2.1 m (near)
Personal distance: 0.75-1.2 m (far); 0.45-0.75 m (near)
Intimate distance: < 00.45
45 m
[Source: CIBSE Guide D]
[Source:
Strakosch,
G R
G.
R., 1998
1998.
The Vertical
Transportation
Handbook]
Planning & Design Factors
• Major design concerns
• Circulation efficiency
• Location & arrangement (prevent bottlenecks)
• Coordination with lobby, stairway & corridor
• Fire & safety regulations
• Handling
H dli capacity
it (quantity
(
tit off service)
i )
• Interval or waiting
g time (quality
(q
y of service))
• Consideration by lift functions
• Passenger, goods, firemen, shuttle, observation
Typical design of “protected” lift lobby
Fire door (one
hour rated)
(shall be free of smoke)
[Source: CIBSE Guide D]
Staircase
(escape route)
Planning & Design Factors
• Escalator – typical design
• Speed: 0.5 and 0.65 m/s, up to 0.9-1.0 m/s on deep
systems like
lik subway
b
• Stepp widths: 600,, 800 & 1000 mm;; min. stepp or
tread length = 400 mm
• Inclination: usually at angle 30o
• 35o if rise < 6 m & speed < 0.5 m/s
• Boarding and alighting areas
• Safe boarding,
boarding 1.33
1 33 – 2.33
2 33 flat steps
Typical escalator design
[Source: Building Services Handbook]
Planning & Design Factors
• Escalator – typical applications
• Low- to medium-rise buildings
• Large no. of people e.g. airports, subway stations,
p
stores,, shopping
pp g malls
department
• Escalator arrangements
•
•
•
•
Parallel
Multiple parallel
Cross-over or criss-cross
Walkaround
Planning & Design Factors
• Escalator: handlingg capacity
p y
• N = (3600 x P x V x cos θ) / L
•
•
•
•
•
N = no
no. of persons moved per hour
P = no. of persons per step
V = escalator
l t speedd (m/s)
( /)
L = length of step (m)
θ = angle
l off incline
i li
• Ce = 60 V k s
(persons/minutes)
• V = speed along the incline (m/s)
g density
y of people
p p (people/step)
(p p
p)
• k = average
• s = number of escalator steps per metre
System Types
• Passenger lifts
• Different requirements in various building types
• Like commercial, hotels, hospitals, residential
• Grouping
p g of passenger
p
g lifts
• Position & layout
• Machine
M hi room/space
/
• Hydraulic lifts: ideally at the lowest level
• Electric traction lifts: directly above the lift well
• Machine room-less lifts
System Types
• Observation lifts
• Glazed or partially glazed lift car within a glazed
or open
open-sided
sided lift well
• Also called wallclimber, scenic, glass, panoramic
or bubble
b bbl lifts
lift
• Within an atrium or external to the building
• Design considerations
• Visual impact (attracting sightseers)
• Lift speed & handling capacity
• Space requirements & maintenance
System Types
• Lifts for the aged & disabled
• Provision for wheelchair
• Good lifts & service lifts
• Car sizes,
sizes payloads,
payloads well dimensions
•
•
•
•
Dumbwaiter ((e.g.
g in restaurants))
Stair lifts
Inclined lifts
Scissor lifts
[Source: CIBSE Guide D]
Scissor lifts
System Types
• Passenger
g conveyors
y
• Other names: travelators, autowalks, moving
walkway moving pavement
walkway,
• Practical limit about 300 m distance
• Useful
U f l in
i large
l
airport
i
t terminals
t
i l
• Design factors
• May be inclined up to about 15o
• Speed between 0.6 to 1.3 m/s (combined with walking,
the overall pace is 2.5 m/s)
• Materials must be flexible or elastic (e.g. reinforced
rubber
bb or iinterlaced
l d steell plates)
l
)
Moving walkway
[Source: Mitsubishi Elevator and Escalator, http://www.mitsubishi-elevator.com/]