Title: Out-of-Plane Reinforcement of Masonry Walls with Steel Reinforced Grout
Author(s): Stefano De Santis, Gianmarco de Felice
Publication: Symposium Paper
Appears on pages(s): 9.1-9.14
Keywords: masonry, out-of-plane, seismic retrofitting, shake table tests.
A shake table investigation was carried out on a full-scale U-shaped masonry assemblage to study the
effectiveness of Steel Reinforced Grout (SRG) for the improvement of the out-of-plane seismic capacity of masonry
walls. Natural accelerograms were applied with increasing scale factor up to failure. A first session of tests was
performed on the unreinforced specimen, that collapsed by out-of-plane overturning. Steel tie bars were then
installed to prevent overturning. In this case, severe damage developed due to bending. Finally, the wall was
retrofitted with horizontal strips of Ultra High Tensile Strength Steel cords, externally bonded to the masonry with
lime based mortar, and steel connectors. SRG led to a significant improvement of the seismic capacity, strongly
limited damage development, and entailed small modifications of the dynamic properties of the specimen. Since the
reinforcement had a thickness of less than 10mm, it is suitable for applications within the plaster layer during the
maintenance work of the façades without modifying their appearance.