The SMAQ system has been designed to extract stone blocks through stitch drilling in quarry. The system is based on the exploitation of the forces and displacements generated by cylinders made of Shape Memory Alloys (SMA) actuated electrically. It is basically composed of two cylindrical splitting shells, containing the SMA actuators, actuated by means of an activation and control system in order to better distribute the stresses and the displacements in the material.
The system is designed to operate in a series of boreholes in parallel, and offers the possibility to dispose two or more splitters in a single borehole at different deeps, therefore generating an optimal distribution of concentrated forces and displacements all over the height of the hole. The advantage from an operational point of view is to extract a block with perfect shape and dimension and no internal damages, improving quality and reducing the need for finishing operations or loss of material.
The high forces generated by the SMAQ system, perpendicular to the splitting plane and distributed all over the height of the block, allow to track with more accuracy the desired splitting line, thus allowing to reduce the number of the holes and the related drilling cost. The characteristics of the system make it suitable for use in different climatic conditions, and where it is not possible or not cost-effective the use of alternative methods like the detonating wire (problems of safety, noise, wire availability) and the expanding clay (slow expansion, not usable at low temperatures, high costs per splitting operation).