Module 4

Vertical transportation systems

Vertical transportation systems
• To provide an accessible path, leading from one
level to another by targeting to meet the needs
of all target groups
 Ramps
• Ramps are sloping surface that can be used to
provide an easy connection from floor to floor
especially when large numbers of people or vehicles
are moving from time to time.
• Indoor Ramps are adopted for buildings, such as
stadiums, railroad stations, exhibition halls, garage
buildings, etc.
• it is generally built with slopes up to 15% (15 cm in
100 cm) but 10% is preferred. With 10% slope and a
storey height of 3metre a ramp connecting two floors
would have to be 30 metre long.
• It can be curved, zigzagged, u-shaped or spiraled and
in all cases should be constructed with a non-slip
surface.
 Design consideration
• An exterior location is preferred for ramps. Indoor ramps are
not recommended because they take up a great deal of space.
• Ideally, the entrance to a ramp should be immediately adjacent
to the stairs.
• Landings - Ramps should be provided with landings
for resting, maneuvering and avoiding excessive
speed. Landings should be provided every 10.00 m,
at every change of direction and at the top and
bottom of every ramp.
• Handrail- A protective handrail at least 0.40 m
• Surface - The ramp surface should be hard and non-
slip.
• Tactile marking - A colored textural indication at the
top and bottom of the ramp should be placed to
alert sightless people as to the location of the ramp.
The marking strip width should not be less than 0.60
m
 Stair and its components
• A stair is a series of steps, each elevated at measured
distance, leading from one level of a structure to another.
Stair parts and terms
• Headroom
• Tread
• Riser
• Unit rise
• Unit run
• Total rise
• Stringer
• Stair well
• Total run
1. Headroom: The clear space between the floor line and ceiling.
2. Tread: Horizontal walking surface of a stair
3. Riser: The vertical stair member between two consecutive
stair treads.
4. Unit rise: The height of the stair riser; the vertical distance
between two treads.
5. Unit run: The width of a stair tread minus the nosing.
6. Total rise: Vertical distance from one floor to another
7. Stringer: A stringer to which blocking has been added to form
a base for adding treads and risers.
8. Stairwell: The rough opening in the floor above to provide
headroom for stairs.
9. Total run: 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.
1. Platform: A horizontal section between two flights of stairs.
Also called a landing.
2. Winding stairs: A curving stairway that gradually changes
direction; usually circular or elliptical in shape. Also called
geometrical.
3. Run of stairs: A series of steps that is a continuous section
without breaks formed by landings or other constructions.
Also called a flight of stairs.
4. Straight run: A stairway that does not change direction.
5. Winders: Wedge-shaped treads installed where stairs turn.
Handrail: A pole installed
above and parallel to stair
steps to act as a support
for persons using the stairs.
also called a stair rail.
Baluster: The vertical
member (spindle)
supporting the handrails on
open stairs.
Newel: The main post at the
start of a stair and the
stiffening post at the
landing.
Nosing: The part of a stair
tread that projects beyond
the riser
Balustrade: An assembly
with a railing resting on a
series of balusters that, in
 Types of stairs
STRAIGHT STAIRS:
• 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 STAIRS:
• Consist of two straight flights
running in opposite directions
• There is no space between the
flights in plan
• Landing is provided at level
which direction of flight changes
 GEOMETRICAL STAIRS :
• 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
CIRCULAR STAIRS:
• 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
QUARTER TURN NEWEL:
• A stair turning through 90° with
the help of level landing
• Used in shop
OPEN NEWEL STAIRS:
• 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 and
public buildings
 Design consideration
• Landing - the width of the landing should not be less
than the width of stairs
• Pitch - Should not be more than 38°

According to KMBR RULES

• Any building having more than four floors including
basement or sunken floors, shall have atleast two
staircases, one of which may be an external stairway.
• Minimum Width of stairs
Residential:-0.8 to 1 m Public :- 1.8 to 2 m
• Minimum width of tread – 30 cms
• Riser – shall not exceed 15cm
• Height of handrail –not less than 90 cms
 Dimensions of a step
Comfortable ascent and descent
• Thumb Rules
• (2 x Rise in cm) + (Going (tread) in cm) = 60
• (Rise in cm) + (Going in cm) = 40 to
45
• (Rise in cm) x (Going in cm) = 400 to
450
• Adopt Rise = 14 cm and Going = 30 cm
as standard;
• then for every 20 mm subtracted from going,
add 10 mm to the rise.
 Requirements of a good stair
• Provide easy, quick and safe mode of communication between
the floors.
• 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.
• Length of flight: The number of steps are not more than 12 and
not less than 3.
• Head Room: Clear space between tread and soffit of the flight
immediately above it should not be less than 2.1 to 2.3 m.
• Balustrade: Open well stair should always be provided with
balustrade, to provide safety to users.
• Step dimensions: 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 going 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.
• Materials of Construction : The materials used for stair
construction should be such as to provide a) Sufficient
strength and b) fire resistance
 Stairs of different materials
TIMBER
• Light in weight and easy to 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.
• In timber stairs, the strings are the support for the stair and act as
inclined beams spanning between the floor and landing
• For additional support, a bearer or carriage may be placed under the
treads.
• A bearer for every 40cm width is provided.
• Thickness of strings may 3 to 5cm and depth = 25 to 40cm.
Steps
• Thickness of tread may be 32mm and that of riser may be 25mm
• Jointed by tongue and groove joints
• Nosing – should not project beyond the thickness of tread.
• Scotia blocks may be provided to improve the appearance of steps
 Stairs of different materials
STONE
• 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 stairs may have following types of steps:
1. Rectangular steps with rebated joint.
2. Spandril steps
3. Tread and riser steps
4. Cantilever tread steps
5. Built – up steps
BRICKS
• Very common except at entrance.
• It contains either solid wall or arched
openings may be left for obtaining storage
space. Frequent maintenance.
STEEL
• Mild steel or cast iron steel are used only
as emergency stairs.
• Not common, though they are strong and
fire resistant.
 RCC STAIR
• Reinforced concrete is perhaps the most suitable of all the said
materials for the construction of stairs. The various advantages
of reinforced concrete stairs are given below –
• They have requisite fire resisting qualities to a great extent –
• They are durable strong pleasing in appearance and can be
• They are durable, strong, pleasing in appearance and can be
easily rendered non-slippery. –
• They can be designed for greater widths, longer spans and any
height.
• They can be moulded in any desired form to suit the
requirements of the architect.
• They can be easily cleaned.
• The cost of maintenance is almost nil.
• The can be pre-cast or cast-in situ.
• To change their appearance, R.C.C. stairs can be covered/
finished with thin slabs of stone, marble tiles or terrazzo finish.
DIFFERENT STAIR ARRANGEMENT IN CASE
OF R.C.C.
• Single Straight Flight Stairs
•Inclined Slab Stairs With Half Space
Landings
•String Beam Stairs
•Crancked Slab Stairs
•Cantilever Stairs
•Spiral Stairs
SINGLE STRAIGHT FLIGHT STAIRS
• Although simple in design and construction is not construction, is not
popular because of the plan space it occupies
• The flight behaves as simply supported slab, spanning from landing to
landing.
• The effective span/ total horizontal going is usually taken as landing
edge to edge by providing a down stand edge beam to each landing.
• If the edge beams are not provided, the effective span would be taken
as over all of the landings, resulting in a considerably increased
bending moment and hence more reinforcement.
SLAB SPANNING LONGITUDINALLY

• In this category, the slab is

supported at bottom and
the top of the flight and
remain unsupported on the
sides.
• Landings also become the
part of slab
• Dog legged stairs are
typical example
• The main reinforcement is
provided parallel to the
direction of the flight and
distribution reinforcement
is provided along the width
of the slab.
STRING BEAM STAIRS: (STAIR WITH
SLAB SPANNING HORIZONTALLY)
• In this category, slab is
supported on one side
by side-wall or stringer
beam and on the other
side by a stringer beam
• Each step is considered
equivalent to a
rectangular beam.
• Main reinforcement is
provided in the direction
of L, while distribution
reinforcement is
provided parallel to the
flight direction
 CRANCKED SLAB STAIRS
• These stairs are very often used as a very often used
as a special feature since the half space landing has
no visible support being designed as a cantilever
slab
• Hence the amount of reinforcement required is high
which can sometimes create site problem with
regards to placing and compacting the concrete
 CANTILEVER STAIRS
• They are also called spine wall stairs.
• They consist of a central vertical wall from
which the flights and half the flights and
half space landings are cantilevered.
• The wall provides a degree of fire
resistance between the flights and is
there fore used mainly for the escape
stairs.
R.C.C.SPIRAL AND HELICAL STAIRS
• Mainly used as accommodation stairs in the foyers of prestige buildings
such as theatres, banks, buildings such as theatres, banks, commercial
complexes etc.
• Can be expensive to construct normally at least seven times the cost of
conventional stairs.
• The plan shape is generally based on a circle; it is also possible to design an
open spiral stair with an eliptical core, which is known as helical stairs.
• The spiral can be designed around a central large diameter circular column
where the steps are cantilevered from that, or in case of helical stairs, can be
designed as open circular well.
 Fire escape stairs
• Out of 2 staircases, 1 can be used as a fire escape staircase.
• Width of fire escape should be minimum 0.75 meter.
• Number of staircases shall be given as per the travel distances.
• Travel or running distance of max 30m
• Staircase shall not be extended to basement to prevent smoke ,
heat & gases. From the basement smoke, heat & gases can travel
to upper floors.
• Access to the basement from the ground should be through a
separate staircase, which is not connected to main staircase (i.e. It
should be remote to each other.
• Route to the external stairs shall be free of obstruction at all times.
• Shall be constructed of non-combustible materials and any doorway
leading to it shall have the required fire resistance. .
• Handrails shall be of a height not less than 1000mm and not
exceeding 1200mm. Provision of balusters with maximum gap of
150mm.
 Composite stairs
• Materials like( marble, tiles, etc.) can be used in
combination with each other so as to formed
what are known as ‘’composite stairs’’
• The various components of stairs are made of
different materials and in addition, the
lightweight materials such as aluminium,
plastic etc. may be employed to construct
composite stairs.
• The stairs of public entertainment places such
as theatres requires special treatment for finish.
 Elevators
• Elevator has been used in buildings having more than 4 stories.
• Lift — An appliance designed to transport persons or materials
between two or more levels in a vertical or substantially
vertical direction by means of a guided car or platform. The
word ‘elevator’ is also synonymously used for ‘lift’.
• Lift Car — The load carrying unit with its floor or platform, car
frame and enclosing bodywork.
• Lift Landing — That’ portion of a building or structure used for
discharge of passengers or goods or both into or from a lift car.
• Lift Machine — 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
• Lift Pit — The space in the lift well below the level of the lowest lift
landing served.
• 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.
• Lift Well Enclosure — Any structure which separates the lift well
from its surroundings.
• Passenger Lift — A lift designed for the transport of passengers.
• Position and/or Direction Indicator — 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.
• Rated Load (Lift) — The maximum load for which the lift car is
designed and installed to carry safely at its rated speed.
• Rated Speed (Lift) — The mean of the maximum speed attained by
the lift car in the upward and downward direction with rated load in
the lift car.
• Generally Two Categories
1) Traction (Electric)
• Virtually limitless rise (high & mid rise)
• High speeds, but high installation cost
2) Hydraulic
• Limited to heights of about 60 ft. (6 stories)
• Lower speeds
• Lower initial cost – higher power
consumption
 Design considerations
• No. of lifts and handling capacity
• Number of floors to be served by the lift;
• ; Floor to floor distance;
• Population of each floor to be served
• Maximum peak demand; this demand may be
unidirectional in up and peak periods, or a two-way
traffic movement.
Preliminary Lift Planning
• population or the number of who require lift service
• Handling capacity of the maximum flow rate
required by these people.
• interval or the quality of service required
 Population
• Average population density can vary from
about one person per 4 m2 to one person
per 20 m2
Quantity of service
Quality of service
Capacity
• The minimum size of car recommended
for a single purpose buildings is one
suitable for a duty load of 884 kg.
• Generally, for large office buildings, cars
with capacities up to 2040 kg are
recommended according to the
requirements
• Speed
Arrangement pattern & spatial effect of Vertical circula
(ELEVATOR)
ARRANGEMENT TWO-CAR GROUPING

•Side-by-side arrangement is best

•Passenger face both cars& can react immediately
•AVOID separation of elevators
•EXCESSIVE separation destroy advantages of group
operation

THREE-CAR GROUPING

•3 cars in a row is PREFERRABLE

•2 cars opposite 1 is acceptable
•PROBLEM: location of elevator call button
Arrangement pattern & spatial effect of Vertical circulati
(ELEVATOR)
Arrangement Four-Car
Grouping

•commonly in large, busier buildings

•2-opposite-2 arrangement is the
most efficient

Six-Car Grouping Arrangement Eight-Car

Grouping
•found in large office buildings,
public buildings & hospitals •the largest PRACTICAL group
•provide quantity & quality •4-opposite-4 arrangement
•3-opposite-3 position is
PREFERRED
•dimension of the LOBBY must not
be less than 3m if function as a
passageway
 Handling capacity
• The handling capacity is calculated by the
following formula: H=(3OOXQX1OO/(TxP )
Where
• 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,
• P = Total population to be handled during peak
morning period. (It is related to the area served by
a particular bank of lifts).
• The waiting interval is calculated by the
following formula: T= RTT/N T= RTT/N
where
• T = Waiting interval in seconds,
• N = Number of lifts
• RTT = = Round trip time, that is, the average
time required by each lift in taking one full
load of passengers from ground floor,
discharging them in various upper floors and
coming back to ground floor for taking fresh
passengers for the next trip
 Types of lift
• Passenger lifts
• Goods lifts
• Hospital lifts
• Panoramic lifts
 1.PASSENGER/TRACTION LIFTS

A passenger elevator is designed to move

people between a building's floors.
SR.No. LOAD CAR INSIDE LIFT WELL ENTRANCE
PERSONS KG A B C D E

1 4 373 1100 700 1900 1300 800

2 6 408 1100 1000 1900 1600 800

3 8 544 1300 1100 1900 1900 800

4 10 680 1350 1300 1900 2100 800

5 13 884 2000 1100 2500 1900 900

 2. GOODS / FREIGHT LIFTS

A freight elevator, or goods lift, is an elevator

designed to carry goods, rather than passengers.
 Freight elevators may have manually operated
doors, and often have rugged interior finishes to
prevent damage while loading and unloading.

SR.No. LOAD CAR INSIDE LIFT WELL ENTRANCE

KG A B C D E

1 500 1100 1200 1900 1500 1100

2 1000 1400 1800 2300 2100 1400

3 1500 1700 2000 2600 2300 1700

4 2000 1700 2500 2600 2800 1700

5 2500 2000 2500 2900 2800 2000

 3. HOSPITAL LIFTS

For simple transportation of a patient on

wheelchair to wheeling away a critical
patient
on bed without disturbing his life support
system with doctors & nurses attendance,
smoothly & silently, without jerks & shocks.

SR.No. LOAD CAR INSIDE LIFT WELL ENTRANCE

PERSONS KG A B C D E

1 15 1020 950 2400 1700 3000 800

2 20 1360 1300 2400 2200 3000 1200

3 26 1768 1600 2400 2300 3000 1200

 4. DUMBWAITER LIFTS

 Dumbwaiters are small freight elevators

that are intended to carry food rather than
passengers.
 They often link kitchens with rooms on
other floors.
 PANORAMICS LIFTS

The panoramic lift applies both to external lifts

on the facades of imposing business premises
from which passengers can enjoy the view and
internal lifts in department stores or in foyers of
large hotels where they look out on to the sales
floors and displays.
 Escalator
• Escalator — A power driven, inclined,
continuous stairway used for raising or
lowering passengers.
• Named Escalator by Charles Seeberger in 1897
by combining the latin word for steps “scala”
and elevator
• Most applications include department stores,
airports, shopping malls, convention centers,
hotels, and public buildings
• One of the largest, most expensive machines
people use on a regular basis, but also one of
the simplest.
• It includes the escalator, the track, the
trusses or girders, the balustrading, the step
treads and landings and all chains, wires
and machinery directly connected with the
operation of the escalator
• Escalators are required to provide continuous mass transport
of people.
• Escalators in department stores rise at an angle of between
(30°-35°). The 35° escalator is more economical, as it takes up
less surface area.
• Have the capacity to move large numbers of people, and they
can be placed in the same physical space as one might install
a staircase.
• Have no waiting interval (except during very heavy traffic)
• They can be used to guide people toward main exits or special
exhibits, and may be weatherproofed for outdoor use.
• Escalator speeds vary from 90 – 180 ft per minute, an
escalator moving 145 ft per minute can carry more that 10,000
people in an hour
 Design consideration
• For normal peak periods, the recommended handling
capacities for design purposes should be taken as 3200 to
6400 persons per hour depending upon the width of the
escalator.
• In accordance with a worldwide standard, the width of the step
to be used is 60 cm (for one person width)80 cm (for one- to
two people width) and 100 cm (for two people width).
• The theoretical capacity then is:
3 600x (rated speed in m/s x k)/O.4
K = 1, 1.5 or 2 for 0.6, 0.8 and 1.0 m step widths.
Criss cross arrangement
Parallel arrangement