Technology: Concrete Paving

How Offset Paving Works

In offset applications, a concrete mixer transfers the concrete to the receiving hopper. The material is transported into the slipform via a swivel-mounted conveyor belt or a swivel-mounted auger conveyor. Depending on the machine model, the conveyor belt is available in various lengths and in a folding version. Different versions of the auger conveyor are also available. Whether belt or auger conveyor – all of the settings such as conveyor speed, slope angle or position can be adjusted at the touch of a button. An additional transverse auger conveyor offers many benefits. For example, the concrete mixer can travel in front of the slipform paver and not need to be off to the side, thereby eliminating the need to close another lane. Despite the fact that a larger quantity of concrete is required as a buffer, the transverse auger conveyor is still an ideal solution – like in tight bends where the concrete mixer is unable to permanently supply the machine with concrete, for example.

How the State-of-the-Art Inset Paving Method Works

In the inset method, concrete is either poured directly in front of the slipform paver or conveyed from the side via a belt conveyor or placer/spreader to the front of the machine. In the next step, the concrete is distributed evenly across the full paving width by a spreading auger or spreading plow. Built-in electrical or hydraulic vibrators ensure homogeneous compaction of the concrete. The inset mold forms the concrete surface to the specified thickness and width while the slipform paver travels forward. In addition, a dowel bar inserter can be added which inserts the dowel bars into the concrete as specified parallel to the paver’s direction of travel. Central tie bars or side tie bars can be inserted perpendicular to the road surface. The oscillating beam scrapes the surface across the roadway. The “grinding movement” produces a small concrete roll in front of the screed that adds to the high quality of the concrete surface. Afterwards, a super smoother can smooth the concrete surface.

How State-of-the-Art Texture Curing Machines Work

How a Placer/Spreader Works

As a rule, the placer/spreader WPS 62(i) is deployed in combination with a slipform paver and a texture curing machine. While tipper trucks or semi-trailers tippers successively feed concrete into the belt conveyor unit’s large receiving hopper, the belt conveyor guides the conveyed material to the center of the road. The WPS 62(i) placer/spreader uses a spreading auger to spread the placed concrete and paves it uncompacted with a narrower width and greater thickness than the following slipform paver. Finally, the paver paves the pre-poured concrete in the required width and thickness together with the pre-placed reinforcing steel. To complete the process, the texture curing machine produces a defined surface structure and sprays evaporation protection onto the fresh concrete road surface.