Push-over analysis of a rubble full-scale masonry wall reinforced with stainless steel ribbons

Abstract

Many strengthening techniques for masonry structures were thoroughly investigated in several researches. The in plane shear behaviour of an ancient full-scale masonry wall, characterized by an opening that is strengthened by the lintel in the arch form, retrofitted with an innovative system constituted by three-dimensional pre-tensioned stainless steel ribbons, was previously tested. In this paper the double flat-jack test results were analyzed and design of the retrofitting system was detailed. The collapse mechanisms in terms of flexural bending and shear, both sliding and diagonal tension, as function of the compression stress level were taken into account. The arrangement of the ribbons was established on the base of an equivalent frame model of the masonry wall, investigating the flexural and shear strength of each element (piers and spandrel). Moreover, the numerical results of the response behaviour modelling of the unreinforced and reinforced masonry wall were presented. The analytical modelling of the wall was accomplished suitably applying the methods of the disturbed stress field model, successfully used for reinforced concrete elements. The numerical results provided a good prediction of the response behaviour of the wall, both in terms of load–displacement curve and crack pattern at failure.