1. CHAPTER 4 BUILDING TRANSPORTATION SYSTEM

2. BUILDING TRANSPORTATION SYSTEM
is the system for conveying people in buildings
The mechanical transportation of people and goods is an energy-using service that needs the designer’s attention at the earliest stage of building design.
System includes: Elevators, Escalators and Walkalators

3. ELEVATORS (LIFTS) Elevator (Lifts)
is a vertical transport equipment that efficiently moves people or goods between floors (levels, decks) of a building, vessel or other structure
Two basic types:
Hydraulic-lifting platform is pushed upward/downward by plunges
Traction-Electric lifts

4. ELEVATORS (LIFTS)
Passanger lifts are provided for buildings of over three (3) storeys, or less if wheelchair movement is needed.
Minimum standard is one lift for each four storeys, with a maximum walking distance of 45m between workstation and lift lobby.
Prestige requirement require higher standards (depends on the rent earning potential)

5. ELEVATORS (LIFTS)
Peak demand for lift service is assessed from the building size, shape, height and population.
25% of the population require transportation during a 5 min peak period.
Congestion at peak travel times is minimized by arranging the lifts lobbies in a cul-de-sac of (2 lift doors on either side of a walkway, rather than in a line of four doors along one wall).
Construction specifications of lifts are given in BS 5655: 1989 and BS Code of Practice 407:1972
Car speed for various travel distance (see table 1)
Table 1: Design lift car speed
Floors
Car speed (m/s) 4 9 15
Over 15
0.75 2 3
5-7

6. ELEVATORS (LIFTS) _Hydraulic
Lifting platform is pushed upward/downward by plunges (ram)
Liquid (oil/high pressure water) is forced into or withdrawn to create movement.
A pump is used to control the liquid
Suitable for moderate car speed and fairly short travel (e.g. hospital)
Speed range between 0.12m/s and 1m/s with maximum height 21m.
Machine room are usually located at the lowest level.
Types: Direct acting (holed)
Suspended (hole less)

7. ELEVATORS (LIFTS) _Hydraulic
Direct Acting- single cylinder that bored into the ground with the cylinder having a depth that reaches the height of the plunger.
Direct Acting

8. ELEVATORS (LIFTS) _Hydraulic
Suspended- required on or two rams to suit the load and located in the shaft (not in the ground hole).
Utilizing the telescopic format to extend the plunges upward.
Suspended type

9. ELEVATORS (LIFTS) _Hydraulic
Advantages
Eliminating rooftop structure ( power pack at low level)
Small machine room & can be located at some distance from the shaft
Load imposed on the shaft is far more less ----offering structural cost economies
No brake or gear necessary
No pulleys of driving sheave
No counterweight and a larger lift car can sometime be used for a given well size
Extremely accurate floor levelling can be achieved
Acceleration and travel is very smooth
Simplification of shaft’s structural design

10. ELEVATORS (LIFTS) _Electric
Principle components- lifting platform, lifting machinery,
counterweight cables.
Gearless
ascend (upward movement) heights for gearless are limited by technology feasibility & cost limitation
the net ascent distance will be limited by factors of mechanical performance capabilities
some commercially available gearless elevators can move up at rates more than the speed suggested in the table 2
Geared
location of gear between motor & drive sheave
small motor provide gear reduction ratio (efficient & comfort)
employed for medium speed & medium height application
used in buildings with greater height & greater lifting capacity

11. ELEVATORS (LIFTS) _Electric
Table 2: Electric Lift Specifications
HEIGHT OF ACENT Ft(m)
NUMBER OF STOPS
SPEED Ft/min
(m/s)
LIFTING CAPACITY Lbs (kg)
Geared
To 300 (90) 30
( )
( )
Gearless To
( )
30-80
( )

12. ELEVATORS (LIFTS) _Electric
Principles of Operation
Roping Arrangements
Single wrap traction
-geared machines or
-gearless (lower speed)
Double-wrap traction
-the use of diversion puller increases the risk of rope slip
-Double-wrap pulley reduces the frictional area of rope with the diving sheave
-used on high speed and heavily loaded elevators.

13. ELEVATORS (LIFTS) _Electric
Roping-Type A
-used with geared machines at lower car speeds
-halves the load on the sheave and allows the use of high-speed motors
-disadvantage: the length of the rope is 3 times of the single-wrap system
Roping –Type B
-used for heavy goods elevators, where it is required to reduce the motor power and pressure
-acting upon the bearings

14. ELEVATORS (LIFTS) _Electric
Size depends on the size & speed of car, type of door
Pit must permits over travel & water tight with proper drainage
Buffer sits to the base (spring /oil) to reduce impact
Allowing air to escape below & above moving car to prevent air pressure building + smoke vent with unobstructed openings
No other services should accommodate shaft
Constructed of reinforced concrete / brickwork ---sufficient strength to carry load & superimposed loads
Fire resistant ---< one hour

15. ELEVATORS (LIFTS) _Electric
Lift Doors
Two sets of doors are required at lift entrances;
1. Car doors fitted to the lift car
2. Landing doors fitted to the lift shaft enclosure
(open metalwork enclosures are no longer allowed)
Landing doors must be made of solid incombustible materials ---reduce fire risk & ensure safety of passengers
Landing doors must have no means by which an authorized person can open them from a landing
Door may be of the following type
1. two-leaf side opening
2. Two leaf centre opening
3. Single-leaf side opening

16. ELEVATORS (LIFTS) Location Considerations
Location of building entrances ---should be located in the central area, or if not, should be centralized
Grouping ---better group than spread, reduces installation cost
Staircase location ---demand of lift reduced if passengers pass stairs first before lift
Departmental stores ---easily seen & accessible to encourage visits to upper floors
Hospitals ---bed lifts required near operating theatres
Lobbies ---desirable & large enough to allow traffic visible from entrance hall

17. ELEVATORS (LIFTS) Number of Lifts
The number & size of lifts must be related to following:
1. Population of the building
2. Type of building occupancy
3. The starting & finishing times of population
4. Number of floor and heights
5. Position of building in relation to public transport services.
Population
When clear figure is unobtainable
Estimation
1.Net floor area
2. Population density per sq meter.
Example: General office building population density of one person
per 10m² of net floor volume

18. ELEVATORS (LIFTS) Round Trip Time
The time in sec taken by a single lift to travel from the ground floor to the top floor, including stops, and return to the ground floor.
Flow rate
A percentage of the total population requiring lift service during a 5 min peak period
Survey (10% -25%) will require lifts during 5 min peak demand hour
If no info available ---assume 12% for speculative buildings & 17% for unified buildings

19. ELEVATORS (LIFTS) Interval (s)
Expressed in seconds & represents the round trip of one car dived by the number of cars in a common group system
Provides a criterion for measuring the quality of service
Average waiting time; theory = ½ of the interval time, practice = ¾ of interval time

20. ELEVATORS (LIFTS) Example
A 15 storey office block has a net floor area above ground level of 8000m². Assuming starting times ad a population density of one person per 10m² of net floor area, calculate the flow rate and from tables, find lift speed, number and capacity of lift.
Check the quality of service form the table.

21. Flow rate
Flow rate – allowing 17% of population from total building occupants
8000m2/10m2 ×17/100 =136 persons during 5 min peak demand period
Travel and speed
Assuming floor height of 3.3m, the lift travel = 14 ×3.3=46.2m. From table 2, the nearest travel for offices is 45m which requires speed of 2.5m/s. (Ground floor is not included)
Table 2
Table 1

22. Table 3 Table 4 Number and capacity of lift
From table 1, for 24-passenger cars may be installed having a handling capacity of 137 and interval of 41s
Table 3
Quality of service
Refer table 1 (green box) interval=41s
From table 3
- interval 41s ---satisfactory
- calculate the waiting time 31s (3/4 x interval)
From table 4
15 storeys/ 4 lift = 3.75 storeys/lift
---satifactory
Table 4

23. ESCALATOR
Continuous conveyors designed for moving large numbers of people quickly and efficiently from one floor to another.
Staircases that could move upward or downward operate continuously during hours of occupancy
Mostly deployed in pairs
Supporting lift services
For example; basement to ground floor where traffic is light; to avoid the need for lift to serve low demand

24. ESCALATOR
1. Bottom; step return idler sprockets, step chain safety switches & curves sections of the rack
2. Centre; carries all straight track sections which connect the upper & lower curved sections
3. Top; driving motor, driving sprockets, electrical controller and emergency breaks
bottom
top
centre

25. ESCALATOR-component

26. ESCALATOR Escalator vs Elevators Advantages
Travel between floors occur much rapidly in lifts
traveling vertically in medium / high-rise building are more practical in elevators
Elevator assemblies occupy less space
Enable movement by wheelchair-bound, stretcher (in case of an emergency)
Advantages
Could be reversible to suit traffic at peak times
Not like lift ----no waiting time
Continuous operation---moves people more
A device to communicate/highlight what is present at the next floor

27. ESCALATOR Capacity Step width between 600mm ~ 1.2m
Carrying capacity depends on speed & width of thread
Ex ; 1m will allow 2 people to stand side by side,1.2m for air terminals & railway stations to allow passenger to pass easily when carrying luggage,2m for departmental store with heavy traffic

28. ESCALATOR Location Easily seen area to maximize usage
Example; in departmental stores, escalators are located to be possible to see over a wide area of the floors so as to encourage sales
Arrangement
Many arrangements may be used depending upon the standard of service required and cost

29. Multiple parallel
Crisscross layout
Parallel Layout

30. ESCALATOR Guidelines for design
1.Estimating how many escalators may be needed. Speed & width (human buffer zone) -----speed----Capacity
2. Placement locations for escalators. Building use-----function
3. Placement format for escalators
• Ways to organize and stack escalators ----parallel, criss-cross, stacked & in-line
• These are distinguished by their basic layout of overall system, pathway between units, traverse direction, upward / downward
4. Sizing issues for placing escalators
Major dimensions for scalators;Incline angle (max 30), horizontal lengths (heights between floors), overall width, opening in floor, headroom between units

31. WALKALATORS/MOVING WALKWAY
A moving walkway or moving sidewalk (colloquially sometimes travelator, horizontal escalator, walkalator, autowalk, movator)
is a slow moving conveyor mechanism that transports people, across a horizontal or inclined plane, over a short distance.
Moving walkways can be used by standing or walking on them. They are often installed in pairs, one for each direction.

32. WALKALATORS/MOVING WALKWAY
Types:
High speed
Widely used in airports, tunnels
allowing for a large number of passengers, (up to 10,000 per hour), whereas the transportation zone was narrower and fast moving.
Required additional safety procedure (holding to the side rail and shopping cart/baby carriage/suitcase is not allowed)
Inclined
An inclined moving walkway is used in airports and supermarkets to move people to another floor with the convenience of an elevator (namely, that people can take along their suitcase trolley or shopping cart, or baby carriage) and the capacity of an escalator.

33. End of Chapter 4