Natural stone reinforcement of discontinuities with resin for industrial processing: Fid-Bau Portal

Natural stone reinforcement of discontinuities with resin for industrial processing

López-Buendía, A.M. / Guillem, C. / Cuevas, J.M. / Mateos, F. / Montoto, M.

Abstract Natural stone is used as a construction material thanks to its aesthetic, mechanical, and durable properties. Frequently, some pieces of stone show weakness planes that are critical from the mechanical point of view because they can restrict their processing in the Stone Industry. Treatment with epoxy resin has become widely used due to good performance and good finishing properties. Crema Marfil (also known as Ivory Cream) has been chosen for this study as a widely used Spanish commercial marble. It corresponds to a well-cemented biosparry limestone that includes 5 main families of discontinuity planes: A: open stylolites; B: partially open stylolite; C: well-cemented stylolite with iron oxides and clay minerals; D: well-cemented stylolite with calcite; and E: calcitic veins. Reinforcement by consolidation under vacuum conditions with epoxy resin was applied in samples and slab of Crema Marfil. Epoxy resin in water emulsion and epoxy resin in solvent were specifically formulated and adapted to the characteristics of the migration properties of weakness planes. The evaluation of the weakness planes strength of untreated and impregnated marble was made by using the Brazilian test. Following a strict criterion of sampling, it was possible to obtain very local and precise information about the strength of those weakness planes and their consolidation improvement. Detailed fractographic study was made based in the selected blocks from the front of the quarry and extracting slabs and core samples for consolidation and testing. Results showed significant improvement in the tensile strength of the weakness planes at laboratory scale that can be applied to the Stone Industry. The methodology will provide a very good tool to evaluate the improvement for any other treatment for mechanical modification, mainly in weakness planes. The consolidation efficiency depends on the nature of the pathway properties (connected porosity, wettability with the resin, permeability, tortuosity) and the strength and adhesion of the resin.

Highlights • A method for mechanical characterization of weakness planes in natural stone is shown. • Fractographic and discontinuities evaluation was made in Crema Marfil marble. • Reinforcement of weakness planes by water borne epoxy was made in marble. • It is used as a methodology to improve the productivity in Stone Industry. • Compatibility and efficiency of resin in stone pathways have been evaluated.