The Moldtech mould for TT slabs allows the casting of slabs with double pre-stressed ribs. These TT slabs are normally used for 2 kind of purposes: as a roof element as well as a base for concrete poured in site.
As a base for concreting, the TT slab is casted with protruding reinforcement on top, which will remain embedded in the concrete casted in situ on the TT slab. In the case of a roof element, the TT slab only has its own embedded reinforcement. This precast element is often used in parking buildings and bridges but also in industrial and commercial buildings.
This equipment is a so-called self-supporting mould, which means that the stressing heads are integrated into the mould. These stressing heads normally allow pre-stressing of the strands up to the amount of 400 tons. At one end of the mould will be the passive head, whose function is basically to retain one end of the strands. In the other end of the mould is the active stressing head, which incorporates slackening jacks and allows a controlled release of the tension remaining in the strands before cut them, once the concrete hardens. The design of the mould as self-resistant mould, simplifies installation and dismantling, making it easier to transfer production elsewhere.
The typical TT slab width is 2,4 meters, but also wider versions are available. In this way, Moldtech can also provide adjustable sides so different slab widths can be casted using the same mould. Regarding to the height of the ribs, it can be reduced by disposing extra baseplate elements, so it is possible to cast TT slabs with a variety of rib height. The length of the TT slabs to be manufactured is determined by transversal stoppers which can be positioned at any place along the length of the mould.
Electric or pneumatic vibration is provided to assure an optimum compaction of the concrete. The vibration system removes the air and increases the resistance of the casted piece. In addition, it makes possible to use special concretes with less water content, what accelerates the curing process and increases the productivity.
In addition, the mould can feature a heating system consisting of finned pipes at the sides and the center of the mould in order to improve the productivity. These pipes are surrounded by isolation canvas creating heat chambers which speed up the curing process.