Construction

Due to the shape of the Xbloc unit, a relatively simple formwork can be used which is made of a limited number of different steel plates. Because of large fill openings in the formwork, pouring and compacting of concrete is straightforward and can be well controlled. In several projects, efficient production was achieved by pouring from the concrete mixer in to the mould from an elevated road.

Typically casting turnaround times of 1 Xbloc per mould per day are achieved. In warm climates, with special measures, turnaround times of 2 Xblocs per mould per day can be achieved. This has for instance been done in Nigeria, Sri Lanka, Indonesia and in the U.A.E.

At various projects symmetrical mould halves have been used, where the mould halves where turned around after striking the mould, for immediate re-use. At other locations concrete with fast strength development has been applied which allows removal of the Xbloc from between the mould halves within 24 hrs after casting.

For Xblocs up to 9 m3 size a minimum concrete grade of C25/30 is used with a minimum tensile strength of 2.5 N/mm2 at 28 days (tensile splitting strength). For each project the concrete class and density are specified by DMC based on design requirements, and project site conditions.

Storage

The units can be stacked in various ways for storage, for example side by side in a half-brick bond (see photo). The storage pattern can be arranged in 1 to 3 layers, depending upon the capacity of the subsoil. Using this pattern, the required storage area amounts to 0.72 D2 for 1 layer storage and 0.36D2 for 2 layer storage [D = unit height]. It should be noted that this area still allows for some space between the Xbloc units to facilitate removal from the storage. The minimum storage area for single layer storage is 0.59 D2. In this case the Xblocs will be touching each other.