STRENGTHENING MASONRY THROUGH BASALT FIBRE STITCHINGS: A SUSTAINABLE AND REVERSIBLE WAY OF PRACTICE

Francesco Monni1, Enrico Quagliarini2, Stefano Lenci3, Agnese Scalbi4

1 A.h.R.T.E. s.r.l. – Architectural heritage Restoration through Tailored Engineering s.r.l., Spin Off of Polytechnic University of Marche, c/o Dept. of Civil and Building Engineering and Architecture, Ancona, Italy, ahrte@univpm.it

2 Polytechnic University of Marche, Departement of Civil and Building Engineering and Architecture, Ancona, Italy, e.quagliarini@univpm.it;

3 Polytechnic University of Marche, Departement of Civil and Building Engineering and Architecture, Ancona, Italy, s.lenci@univpm.it

4 Polytechnic University of Marche, Departement of Civil and Building Engineering and Architecture, Ancona, Italy, a.scalbi@univpm.it

ABSTRACT

Stitching masonry through basalt fiber (BF) ropes is an innovative technique, able to connect the several masonry elements and to lend it a monolithic behavior according to the principles which govern the intervention on existing buildings: minimal intervention, research of compatibility, reversibility, respect of authenticity, matter conservation, control of the visual impact and possibility of recognizing the intervention. Continuous BF are obtained by melting basalt and seem to be a good alternative to glass and carbon fiber: they are fire and chemical resistant and present a high compatibility with masonry. The proposed technique is based on the reinforcement and connection of external masonry shell through insertion of BF ropes in the mortar joints previously partially grooved and small diameter holes to allow the crossing of the masonry panel. The technique has been already tested and proved to be effective for improving the behavior against vertical compression actions when applied with synthetic adhesive. In this work, an experimental campaign on masonry panels subject to “out-of-plane” loads, using different types of BF stitching layout is presented. The results indicate the effectiveness of this dry retrofitting system (with no use of synthetic adhesive), increasing the performance of masonry wall specimens not only against “in plane”, but also “out-of-plane” actions, and the full sustainability of the technique.

Key-words: Dry strengthening techniques, basalt fibre, sustainable retrofitting.