Masonry Elements Strengthened with TRM: A Review of Experimental, Design and Numerical Methods

Abstract

Textile-Reinforced Mortar (TRM) is a modern and compatible strengthening strategy for existing masonry, which consists in plastering the walls by means of mortar layers with embedded grids or textiles made of long fibers. TRM can be very useful for the reduction of the seismic vulnerability of masonry buildings, since the fiber-based reinforcement, carrying high tensile stresses, opposes the widening of cracks and provides “pseudo-ductility” to the masonry. The increasing number of available studies on the subject testifies to its relevance but also the lack of a standardized or well-establish approach to quantify the benefits of these systems on the performance of masonry. The present review is aimed at providing a broad overview of how the study of TRM-strengthened masonry elements has been addressed in the literature. In particular, the main features of the different experimental tests are compared, dealing with both in-plane and out-of-plane behavior. Moreover, the different design methods and numerical modeling strategies are presented and discussed.

Multi-layer modelling of masonry structures strengthened through textile-reinforced mortar

“…The development of these modern techniques has actively involved the field of scientific research at different levels: the study of the mechanical and chemical behaviour of the compounds 5-10 , the testing of TRM strengthened masonry elements [11][12][13][14][15][16] , the calibration of numerical and analytical methods for the performance prediction [17][18][19][20][21] . The main research achievements in these fields have been recently reviewed, analysed and discussed by the author 22,23 : it emerged a populated and variegated experimental scenario. Clearly, as the scale and the complexity of the tests increases, the number reduces, due to the higher experimental effort; moreover, the great variability in the materials combinations, geometry, loading and boundary conditions, makes unable to cover experimentally all possible arrangements.…”

Masonry elements strengthened through Textile-Reinforced Mortar: application of detailed level modelling with a free open-source Finite-Element code

“…The application of TRM can be an effective 2 strengthening strategy against many recurrent damage modes affecting historic, unstrengthened masonry buildings subjected to exceptional lateral actions, such as earthquakes. The benefits of several TRM systems on the mechanical performances of masonry elements against the typical failure mechanism related to in-plane actions (diagonal cracking and in-plane bending failure mechanisms) and out-of-plane actions (out-of-plane bending failure mechanism) have already been extensively investigated experimentally, as pointed out the broad literature review recently performed by the author [1]. The influence of TRM on the masonry failure modes is typically evaluated by comparing the performances of unstrengthened and strengthened samples.…”

“…Numerical simulations permit to extend the experimental evidences to a wider variety of TRM layouts and setups and to deeply investigate on optimized intervention and design strategies with a reduced experimental effort, which can be limited to more simple tests for the calibration of materials and interfaces laws and to target validation tests. However, the literature analysis of the numerical studies available on TRM strengthened masonry elements, performed in [1], evidenced the lack of a comprehensive approach, rather than models calibrated and applied for the reproduction of a specific test setup and combination of materials.…”

Sourcing Limestone Masonry for the Restoration of Heritage Buildings: Frumoasa Monastery Case Study

“…The replacement of degraded stones in existing historic constructions is a deep-rooted practice in restoration work. Regardless of whether a strengthening system is to be applied or not, the masonry substrate should first be prepared and repaired to meet its initial constructive and appearance features [ 5 , 6 , 7 ]. In Europe, an ample debate has been held for decades on the priority and significance of the selection criteria for the materials used in restoration work [ 8 , 9 , 10 ].…”