A 3D optimization algorithm for sustainable cutting of slabs from ornamental stone blocks

Ornamental stones are natural building materials, extracted from quarries, which need to be cut and processed sustainably. Natural discontinuities adversely affect the sawing/cutting of blocks into commercial-size slabs. This work presents a 3D optimization algorithm for the sawing/cutting of ornamental stone blocks. The developed algorithm is based on 3D modeling of discontinuities as data input. The algorithm search for the intersection between a 3D cutting grid formed of a determined size of slabs and the model of discontinuities leading to calculate the recovery ratio considering several cutting orientations and displacements of the 3D cutting grid. The algorithm was coded in a program named SlabCutOpt that allows speed problem solving. SlabCutOpt was implemented on a real case study of a commercial-size limestone block extracted from a quarry in Italy. A number of 37 different commercial-sizes of slabs forming 37 cutting grids were tested to investigate the optimum results in geo-environmental direction (recovery ratio) and economic direction (revenue). The findings revealed that a certain slab size gave the optimum recovery ratio, whilst another slab size provided the optimum revenue.