Travelators and Lifts in Construction

Travelators (or moving pavements) are a means of conveying people horizontally or up a slightly inclined plane (up to a maximum angle of 12°, or 21%). The big advantage of the travelator lies in its ability to transport prams, invalid chairs, shopping trolleys, bicycles and unwieldy packages with only a slight risk of accident. At the planning stage the expected traffic must be carefully calculated, so that the installation provides the best conveying capacity possible. This capacity depends on the clear width available, the speed of travel and the load factor.

The number of people transported can be as high as 6000-12000 people/h. The speed of travel on inclined travelators is normally 0.5-0.6m/s although where the inclination angle is less than 4° they can sometimes be run a little faster, up to 0.75m/s. Long travelators can be up to 250m in length but shorter runs (e.g. about 30m long) are better because they allow people to access and exit to and from the sides. It is therefore sensible to plan a series of smaller travelators.

The advantage of the reversible travelators is their ability to offer both horizontal directions of travel - (9) – (10), in contrast to (7) - (8). The low height required for construction (this being only 180mm) allows these travelators to be fitted into existing buildings.

The cotangents of the travelator gradient are:
Gradient W(°) 10° 11° 12°
cot W 5.6713 5.1446 4.7036
Horizontal length L = cotan W x conveyor lift

Example: conveyor lift, 5m; gradient 12° L = 4.7036 x 5 = 23.52 m (to two decimal places).

Lifts. The upward and downward movement of people in newly erected multistorey buildings is principally achieved by lifts. An architect will normally call in an expert engineer to plan lift installations. The guidelines given here are based on German standards. In the UK, lift installation is covered by BS 5655, which contains recommendations from CEN (Committee for European Normalisation) and the International Standards Organisation. It is anticipated that future standards relating to lifts will be fully international in their scope.

In larger, multistorey buildings it is usual to locate the lifts at a central pedestrian circulation point. Goods lifts should be kept separate from passenger lifts; though their use for carrying passengers at peak periods should be taken into account at the planning stage.

The following maximum loads are stipulated for passenger lifts in blocks of flats:
- 400kg (small lift) for use by passengers with hand baggage only
- 630kg (medium lift) for use by passengers with prams and wheelchairs
- 1000kg (large lift) can also accommodate stretchers, coffins, furniture and wheelchairs (8).

Lobbies in front of lift shaft entrances must be designed and arranged so that: (1) the users entering or exiting the lifts, even those carrying hand baggage, do not get in each other's way more than is absolutely necessary; and (2) the largest loads to be carried by the lift in question (e.g. prams, wheelchairs, stretchers, coffins and furniture) can be manoeuvred in and out without risk of injuring people or damaging the building and the lift itself. Other users should be not be obstructed by the loads more than is absolutely necessary.

For a lobby in front of a single lift: (1) the available minimum depth between the wall of the lift shaft door and the opposite wall, measured in the direction of the lift car, must be at least the same as the depth of the lift car itself; and (2) the minimum area available should be at least the same as the product of the depth of the lift car depth and the width of shaft.

For a lobby in front of lifts with adjacent doors the available minimum depth between the shaft door wall and the opposite wall, measured in the direction of the lift car depth, should be at least the same as the depth of the deepest lift car.