Hauling of materials, machines and/or personnel around and between building sites can be very time consuming, expensive and unproductive. Movement of materials within a short distance can be done by using any one of the movement-equipment explained in the previous section.
Transportation between sites of men, machines and materials is usually carried out by using lorries, trucks, rubber-tire tractors with wagons or crawler tractors with wagons. Such transport equipments are discussed below.
1. Trucks
These are essential equipment on any construction project. They are available in various sizes and types. The capacity varies from 0.4–20 m3. The average speed of the truck varies from 10–20 kmph and top speed from 30–100 kmph. They are classified into three categories based on the capacity as (i) light (1/2–1 tonne), medium (1.5–3 tonne) and heavy (3.5–10 tonne) trucks. Trucks are also specified by their total number of wheels and the number of wheel drives. For normal load condition of road a 4 × 2 truck having four wheels, two of them only being driving wheels is quite popular. Under poor road condition and for heavy loads a 6 × 6 or 4 × 4 truck would be required.
2. Dump Trucks
These trucks are fitted with automatic unloading devices. The loading is done either by loading shovels or loaders. These trucks may have capacities as high as 50 tonnes. These trucks can be rear dump trucks, bottom dump trucks and side dump trucks.
3. Dumpers
Trucks with special pneumatic wheels and capable of moving at high speeds having short chassis and strong dumping bodies are known as dumpers. The material can be dumped in front or at the back. The loading, transporting and dumping can be done in quick succession. They are available in capacities up to 4.5 m3.
4. Trailers
Trailers are carriages hauled by power units such as tractors or trucks. Trailers are of two types, viz., full trailer or wagons and semi-trailers. Full trailers are provided with power unit with swivelling axle and drawbar. The semi-trailers are supported in the front by the power unit and at the rear on their own wheels. These trailers can also be operated in a smaller space. Both these trailers are provided with hydraulically-operated breaking systems.
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