Arch 3125 (Vertical Transportation)-L2.pptx

Mechanical Equipment in Building
ME 3125
Credit: 2.00
Arup Kumar Debnath
Lecturer
Department of Mechanical Engineering
Khulna University of Engineering & Technology
Vertical Transportations
Stairs & Elevators
Prepared by:
Pranto Karua
Assistant Professor, ME, KUET

Vertical Transportation
 Vertical Transportation Systems refers to the service component within a building which enables
us to travel vertically between floors much quicker and effortlessly.
 It may be considered the most important building services system for high-rise buildings.
 The vertical transportation system is a crucial element in the efficient operation of a building and
for the experience and comfort of building occupants.
 It includes all kinds of transportation media within buildings, such as lifts, escalators, hydraulic
hoists and passengers conveyors etc.
2

Stairs is a term applied to a complete flight of steps between two floors.
Stairs
Elevators or lifts
An elevator or lift is a vertical transport vehicle that efficiently moves people or goods
between floors of a building.
3

Moving Ramps
Escalators
Ramps are inclined surfaces that join different levels of a space. Commonly used at the entrances
of buildings to accommodate level changes.
An escalator is a power driven moving staircase which carries people between floors of a building.
4

Stair
• Headroom
• Tread
• Riser
• Unit rise
• Unit run
• Total rise
• Stringer
• Stair well
• Total run
5

Stair
• Handrail
• Wall rail
• Baluster
• Balustrade
• Newel Post
• Nosing
6

Stair
• Platform
• Winding stairs
• Run of stairs or flight
• Straight run
7

Components of Stair
Headroom The clear space between the floor line andceiling.
Tread Horizontal walking surface of a stair
Riser The vertical stair member between two consecutive stair treads.
Unit Rise The height of the stair riser; the vertical distance between two treads.
Unit Run The width of a stair tread minus the nosing.
Vertical distance from one floor to another
Total Rise
A stringer to which blocking has been added to form a base for adding treads and risers.
Stringer
The rough opening in the floor above to provide headroom for stairs.
Stairwell
The horizontal distance occupied by the stairs; measured from the foot of the stairs to a
point directly beneath where the stairs rest on a floor or landing above.
Total Run
8

Components of Stair
A horizontal section between two flights of stairs. Also called a landing.
Platform
A curving stairway that gradually changes direction; usually circular or elliptical
in shape. Also called geometrical.
Winding stairs
A stairway that does not change direction.
Wedge-shaped treads installed where stairs turn.
A pole installed above and parallel to stair steps to
act as a support for persons using the stairs.
The vertical member (spindle) supporting the handrails on open stairs.
Straight Run
Winders
Handrail
Baluster
Newel The main post at the start of a stair and the stiffening post at the landing.
Nosing The part of a stairtread that projects beyond the riser
9

Types of Stair
Straight Stair
• All steps lead in one direction.
• This may be continuous with two flights with an
intermediate landing.
• Adopted when staircase is narrow and long.
• Provided mostly in porch, entrance etc.
Dog Legged Stair
• Consist of two straight flights running in opposite
directions.
• Landing is provided at level direction of flight
changes.
10

Types of Stair
Geometrical Stair
Circular Stair
• These stairs may have any geometrical shape and they
require no newel post.
• This type of stair is similar to open newel stair except the
well formed between forward and backward flight is
curved.
• Change of direction in such stairs is achieved by winders
and not by landings.
• All the steps are radiate from a newel post or well hole.
• All the steps are winders.
• This is provided where space is limited and traffic is casual.
• Mostly located at rear of building.
11

Types of Stair
Quarter Turn Newel
Open Newel Stair
• A stair turning through 90° with the help of level
landing.
• Used in shops and public buildings.
• Popularly known as open well stairs.
• A well or opening is left between forward and
backward flight.
• The opening is generally used for installation of
lift.
• A short flight may or may not provided in these
stairs. 12

Requirements of a Good Stair
Following are the general requirements which a stair should fulfill.
Location
 It should be so located as to provide easy access to the occupants building.
 It should be so located that it is well lighted and ventilated directly from the exterior.
 It should be so located as to have approaches convenient and spacious.
Width of Stair
 It should be wide enough to carry the user without much crowd and in convenience.
 Depends upto its location in the building and type of the building.
 In a domestic building, a 90cm wide stair in sufficient while in public building, 1.5 m to 1.8
m width may be required.
13

Length of Flight
Pitch of Stair
 The number of steps are not more than 12 and not less than 3.
 A comfortable slope is achieved when twice rise plus going is equal to 60 cm approx.
pitch should however, be limited to 30o degree to 45O
 Clear space between tread and flight immediately above it should not be less than 2.1
to 2.3 m.
Headroom
Balustrade
 Open well stair should always be provided with balustrade, to provide safety to users.
14

Step Dimensions
Materials & Construction
 The rise and tread should be of such dimensions as to provide comfort to the users. Their
proportion should also be such as to provide pitch of the stair. The path should not be less
than 25 cm, though 30 cm going is quite comfortable. The rise should be between 10 cm to
15 cm. The width of landing should not be less than width of stair.
 The materials used for stair construction should be such as to provide a) Sufficient
strength and b) fire resistance.
15

Stairs of Different Materials
Timber
 Light in weight and easy construct, but poor fire resistance
 Used for small rise residential buildings, unsuitable for high rise residential and public buildings.
Hardwood ( oak, mahogany etc.)
 It should be free from fungal decay and insect attack.
 Widely used where ashlar stone is readily available.
 Quite strong and rigid, though they are very heavy.
 Stone should be hard, strong and resistance to wear and fire resistance also.
Stone
16

Stairs of Different Materials
Bricks
Steel
 Very common except at entrance.
 It contains either solid wall or arched openings may be left for obtaining storage space.
 Frequent maintenance.
 Mild steel or cast iron steel are used only as emergency stairs.
 Not common, though they are strong and fire resistant.
 R.C.C stairs are the one which widely used for residential, public and industrial buildings.
 Strong, hard wearing and fire resisting.
 Usually cast in situ, and a variety of finishes can be made on these.
R.C.C
17

Elevators or Lifts
 A lift or an elevator is a transport device used to move goods or people vertically.
 They are generally powered by electric motors that either drive traction cables and counterweight
systems.
 Elevators are often a legal requirement in new multi-story buildings.
18

Components of a Lift
The load carrying unit with its floor or platform, car frame and
enclosing bodywork.
Lift Car
Lift Landing
This portion of a building or structure used for discharge of passengers
or goods or both into or from a lift car.
Lift Machine or Machine Room
The part of the lift equipment comprising the motor and the control
gear therewith, reduction gear (if any), brake(s) and winding drum or
sheave, by which the lift car is raised or lowered.
The space in the lift well below the level of the lowest lift landing served.
Lift Pit
19

Lift Well
The unobstructed space within an enclosure provided for the vertical movement of the lift car(s)
and any counterweight(s), including the lift pit and the space for top clearance.
Any structure which separates the lift well from its surroundings.
Lift Well Enclosure
A device which indicates on the lift landing or in the lift car or both, the position of car in the lift
well or the direction or both in which the lift car is traveling.
Position or Direction Indicator
20

Counter Balance Weight
A unit, consisting of steel weights, which counter balance the weight of car and a portion of the
load to which ropes are attached.
Elevator Hoistway
An elevator hoistway is the shaft constructed to allow elevators to move efficiently between the
floors of a building.
Rated Load
The maximum load for which the lift car is designed and installed to carry safely at its rated
speed.
Rated Speed
The maximum speed attained by the lift car in the upward and downward direction with rated
load in the lift car.
21

Location of Elevators or Lifts
 Positioning of lift should be at locations which provide easy means of access for all building
users – central entrance lobby of offices, hotels, apartments, etc.
 Some of the lift grouping arrangements are shown below:
 Grouping of lifts is essential for user convenience.
1
1 2
1
2
3
 Lifts should be sited in the central area and take into account the proximity of entrances to the
building and staircases.
22

Location of Elevators or Lifts
 When a building has to have a number of passenger lifts, it is usually preferable to group them
together rather spread them throughout the building. Although passenger walking time is saved by
spreading the lifts, this is more than offset by the increase in average waiting time for the lift
service and passengers tend to be more impatient standing waiting for a lift than they are by
walking to it.
 In departmental stores, shoppers must be encouraged to visit the upper sales floors and therefore
lifts in these buildings should be easily seen and accessible.
 In all types of buildings, lift lobby is desirable and should be large enough to allow traffic to
move in both directions on the landing without being obstructed by people waiting for the lift.
 In hospitals, a bed lift will be required close to the operation theatre in addition to other lifts.
 Lift lobbies should be visible from entrance hall from the lift, as they hold the lift for late arrivals,
case disturbances and also wear of the control system.
23

Number of Elevators or Lifts
The number and size of lifts must be related to the following:
 Population of the building.
 Type of building occupancy.
 The starting and finishing times of the population, whether staggered or unified.
 Number of floors and heights.
 Position of building in relation to public transport services. A building near a traffic terminal
generally has high passenger peaks during arrival hours.
Population
 If a definite population figure is unobtainable, an estimate can be made from the net floor area
and the probable population density per square meter. The average population can vary between
one person per 4 m2 to 20 m2, but the building owner should be able to give a reasonable figure.
 For general office buildings, a population density of one person per 10 m2 of net floor area may
be assured.
24

Number of Elevators or Lifts
Flow Rate
Interval for Lifts
 This is usually expressed as a percentage of the total population requiring lift service during a 5
min peak demand period.
 Surveys have shown that between 10 percent and 25 percent of the total population will require
transportation during a 5 min peak demand period.
 If no information is available on the expected flow rate, 12 percent may be assumed for
speculative buildings or where staggered starting times will be practiced and 17 percent for
buildings which will have unified starting times.
The interval is expressed in seconds, and represents the round trip time
of one car divided by the number of cars in a common group system,
it provides a criterion for measuring the quality of service. The average
waiting time may therefore be expressed theoretically as half this
interval, but in practice it is probably nearer three quarters of the interval.

Speeds of Elevators or Lifts
Lift Travel
 The travel of a lift is the number of floors above ground multiplied by the floor heights.
Lift Speeds
The recommended lift speeds for various building heights are given below:
 Four 18-person lifts provide the same capacity as three 24-person lifts but the waiting time will
be about twice as long with the three-car group.
26

Lift Performance
Round Trip Time
 The time in seconds by a single lift to travel from the ground floor to the top floor, including the
portable number of stops and return to the ground floor.
Lift Performance
If the travel speed and building population are known; the interval, number of lifts and the
number of passengers to be carried by each lift may be found. which gives an indication of the lift
performance. Lift performance depends on the following factors:
■ Acceleration
■ Retardation
■ Car speed
■ Speed of door operation, and
■ Stability of speed and performance with variations of car load
 It is used for estimating and comparing efficiency and effectiveness of lift installation.
27

Calculation of Round Trip Time
A building having five floors at 3 m floor to floor spacing, a car capacity of 6 persons
and 2 ms-1 speed of travel. Calculate The round trip time (RTT).
Problem-1.1
1. Probable Number of Stops:
29

Problem-1.1
2. Upward Journey Time:
30

Problem-1.1
3. Downward Journey Time:
V
d
T 
L
 2V
2

12
 [2 x 2]  10 s
4. Passenger Transfer Time:
Allow 2 – 3 s per person to transfer, depending on the depth of car. At 2 s:
Tp  2n  2 x6  12s
31

Problem-1.1
5. Door Opening Time:
6. Round Trip Time:
Assume door speed (Vd) = 0.5 ms-1 and door width (W) = 1.2 m:
Vd 0.5
o 1  2 (3 1)
1.2
 19.2 s
T  2 S 1W
RTT  Tu  Td  T p  To
 16.5101219.2
 57.7 s 32

Estimation of the Interval and Quality of Service
Problem-1.2 An office block with 20 storeys above ground floor having a group of four lifts with
unified starting and stopping times is to have a floor area above the ground floor of 8000 m2 and floor
height of 3 m. Each car of the lifts has a capacity of 20 persons and a speed of 2.5ms-1. The clear door
width is to be 1.1 m and the doors are to open at a speed of 0.4 ms-1. Estimate the peak demand,
interval and quality of service that is to be provided.
2
 124 person
11m 2
/ person *100
8000 m *17%

1. Peak Demand for a 5-min Period:
2. Car Travel:
Car Travel = 20 * 3 m = 60 m
34

3. Probable Number of Stops:
width is to be 1.1 m and the doors are to open at a speed of 0.4 ms-1. Estimate the interval and quality
of service that is to be provided.
35

4. Upward Journey Time:
36

V
d
T 
L
 2V
2.5

60
[2 2.5]  29s
5. Downward Journey Time:
37

Given, door speed (Vd) = 0.4 ms-1 and door width (W) = 1.1 m:
6. Door Opening Time:
Vd 0.4
o 1
T  2S 1W
 2(111)
1.1
 66s
38

Passenger transfer time (Tp) = 2n
= 2 * 16 = 32 s
7. Passenger Transfer Time:
RTT =Tu Td Tp To
 79296632206s
8. Round Trip Time:
39

9. Capacity of the Group:
10. Interval for the Group:
=
5 mins60416
206
 93persons per 5 minutes
=
206
4
= 51.5 s
The capacity of the group of lifts and the
interval for the group are satisfactory.
(Note: Car less than 12 capacity are not
satisfactory)
Peak time period
Number of lifts
Number of persons
40

Criteria for Comfort and Convenience of Lift Users
■ Directional indication of location of the lift lobby for people unfamiliar with the building.
■ Call buttons at landings and in the car positioned for ease of use with unambiguous definition for
up and down directions.
■ Call buttons to be at a level appropriate for use by people with disabilities and small children.
■ Call display at landings needs to be favorably positioned for a group of people to watch the
position of all cars and for them to move efficiently to the first car arriving.
■ Call lights and indicators with an audible facility to show which car is first available and in
which direction it is traveling.
■ Lobby space of sufficient area to avoid congestion by lift users and general pedestrian traffic in
the vicinity.
33

Preliminary Design of Elevator
The handling capacity is calculated by the following formula:
H=(3OO * Q * 1OO) / (T * P)
Handling Capacity
H = Handling capacity as the percentage of the peak population handled during 5 min period,
Q = Average number of passengers carried in a car, T = Waiting interval in seconds, and
P = Total population to be handled duringpeak morning period.
(It is related to the area served by a particular bank of lifts)
Where,
Waiting Interval
The waiting interval is calculated by the following formula:
T= RTT/N T = Waiting interval in seconds
N = Number of lifts
RTT = Round trip time
Where,
41

Preliminary Design of Elevator
(Taking 80% of
the capacity) 42

Other types of Elevator
An elevator designed to carry goods, rather than passengers.
Freight Elevator
An elevator designed to carry cars.
Car Elevator
43

Dumb Waiter
Platform Elevator
A small box elevator designed for the carriage of lightweight freight is called a dumb waiter.
This type of lift is used for the disable persons.

Other Types of Elevator
Fire Fighting Lift
■ For rapid emergency access.
■ The original concept was a variation within conventional
passenger lift, which contained a priority break-glass key
switch.
■ This was normally at the ground floor, and when activated
it brought the lift to that floor immediately.
■ Independent fire-fighting lifts are required in offices, shops
and other commercial premises exceeding 18 m in height.
45

Specific Provisions of Fire Fighting Lift
■ 630 kg minimum duty load to accommodate fire-fighting
equipment.
■ Minimum internal dimensions of 1100 mm width, 1400 mm
depth and 2000 mm height.
■ An emergency hatch in the car roof.
■ Manufactured from non-combustible material.
■ A two-way intercom.
■ 1 hour fire-resisting doors of 800 mm minimum width * 2 m
height.
■ A maximum of 60 sec capability to run the full building
height.
■ Dual power supplies, one direct mains and the other an
emergency generator. 46

Maintenance of Elevators
Only authorized persons, who have been approved by the electrical engineer of Govt. can take up
maintenance of elevators. The agency must inspect the lift once in the quarter and should attend to all
calls as and when required. The agencies is supposed to undertake the routine works such as:
 Lubrication of wire rope and guide rails.
 Checking of levels of machine pits.
 Motor greasing.
 Cleaning all the equipment.
 Adjustments in electrical circuits, landing gate lock and car gate switches.
 Inspection of hoists way switches.
 Painting of all structural steel members.
 Electrical circuit diagram of lift installations must be displayed in conspicuous positions.
 Maintenance of record book all items relating to general servicing and inspection.
47

Arch 3125 (Vertical Transportation)-L2.pptx

Recommended

Recommended

More Related Content

Similar to Arch 3125 (Vertical Transportation)-L2.pptx

Similar to Arch 3125 (Vertical Transportation)-L2.pptx (20)

Recently uploaded

Recently uploaded (20)

Arch 3125 (Vertical Transportation)-L2.pptx