The Reticulatus method for shear strengthening of fair-faced masonry

Abstract

This paper presents the results of several experimental campaigns recently carried out by the authors and devoted to the investigation of the mechanical performance of wall panels strengthened by applying repointing mortar and high strength stainless steel or composite cords. The reinforcement system, known as Reticulatus, allows the reinforcement of regular and irregular-shape masonry walls, when the fair-faced aspect must be kept. In the perspective of using this reinforcement method, this article summarizes the research that has been done so far, presenting new original test results and discussing the design procedures. Twenty-two square wall panels were loaded in their plane by means of a single point load acting through the panel's diagonal. Experimental results are presented for four types of cord 2 reinforcement using matched samples, reinforced and not. Increases in shear strength from 15 to 170% were achieved for the strengthened panels. Each wall panel was loaded well into the lateral post-elastic regime and then unloaded.Experimental results were in good agreement with predictions from simple models which assume the wall panels to behave like a plate, neglecting the contribution of the repointing mortar, and accounting for the non-linear behavior of the masonry.

Strengthening/Retrofitting Techniques on Unreinforced Masonry Structure/Element Subjected to Seismic Loads: A Literature Review

“…Besides the difference of improvement on retrofitting materials, the improvement of same retrofitting material on different masonry structures varies as well. [64] found that the shear strength of the retrofitted pebble masonry was improved about 40% while 17% for stone masonry by using the same retrofitting technique. As this reinforcing system can keep the original aesthetic of the building, it is therefore suitable in reinforcing the fair-face masonry or the masonry heritages.…”

“…After that, the reinforcement and anchoring bars will be covered by re-pointing mortar back to the joints. The dimension of the reinforcement mesh normally ranges from 300-500mm, and it must be smaller than the thickness of the panel [64]. The detailed configuration of a typical reticulatus system is displayed in Fig.…”

In-Plane Behavior of Cracked Masonry Walls Repaired With Titanium Rods

“…In order to improve the effectiveness of the metal reinforcements, new materials and methods have been experimented. An example is the use of ultra-high strength steel fibres [9][10][11][12][13] and stainless steel profiles [14][15][16][17][18]. Composite materials continued to be used for historic masonry reinforcement, but their application was made not with epoxy adhesives, but with metal fasteners or inorganic (lime-or cement-based) mortars [19][20][21][22][23].…”

Seismic retrofit of historical masonry walls by means of natural basalt fiber strips system (BFRP). Pre-modern concepts and innovative materials

“…On the efficacy and potential for use of innovative materials such as FRP or UHTSS, high strength stainless steels, applied in the form of a grid (Reticulatus System) in the field of seismic retrofit of masonry walls belonging to historical buildings, it has been widely written in the specific scientific literature [20][21][22][23][24][25][26][27]. The traditional timber frame reinforcements can be effectively replaced by a homologous frame, according to a similar geometric pattern, composed of natural basalt fiber strips, arranged in adherence to the wall front and glued to the wall itself by means of a GeoCalce (a KeraKoll patent), a hydraulic lime matrix compatible with the traditional binder present in the walls (Fig.…”