Abstract: A module (100) for a system for the laying of underground and railroad and tram lines both in tunnel and on the surface, in particular railroad and tram lines, comprising a supporting slab (101) for the tracks (6), with substantially parallelepiped shape, the slab having at least four peripheral housings (1), passing from the extrados to the intrados and suitable to house respective adjustable levelling devices (120).

Abstract: A process and apparatus are disclosed for production casting of railroad ties and the like to obtain maximum mold utility. The casting is accomplished by arranging tendons within a mold and subjecting them to an appropriate tensile stress. Uncured concrete is then introduced at a temperature of around 80.degree. C.-90.degree. C. The mold is vibrated and subsequently closed. It is then maintained at 60.degree. C.-80.degree. C. for a time sufficient to cure the concrete such that the prestressing mechanism can be released. The mold may then be immediately re-used. One mechanism by which the molds may be closed during the curing process in most efficient manner is to employ succeeding molds in a stacked arrangement to cover each preceding mold cavity. A single piece conical locking member is also employed to anchor the tendon in the mold.