Tarmac-laying machines

Advancements in engineering mean road laying is no longer a time-consuming and resource-draining part of construction

Roads, bridges, car parks – almost everywhere you look in urban areas you can see asphalt and tarmac providing a smooth surface for our vehicles. As our cities get larger and the demand for high-quality paving continues to increase, engineers and construction workers have traded their old tools for new machines. In the past, dropping hot tar onto the road and spreading it across the ground manually was the best way to pave a surface, but today paving machines make the process faster and more efficient.

The first of its kind came in 1934 when Barber-greene, an American paving company, introduced the Model 79 asphalt laydown machine. The self-propelled laydown machine revolutionised the industry by introducing the free-floating screed, a new component that would help make the asphalt smoother. The screed works to evenly spread the paving material across the road as it is connected to the paver only by a tow arm that allows it to

‘float’ vertically relative to the paver.

This means that the paver is able to lay a flat surface even on uneven ground as the screed naturally changes the amount of material extruded from the paver in accordance with bumps and dents in the original surface.

Since the introduction of the Model

79, asphalt pavers have remained relatively unchanged, with the paving material loaded into a hopper at the front and carried to the rear by conveyor belts before being spread out by augers and levelled with a screed. Today, all paving machines consist of a tractor and a free-floating screed.