Experimental Research on Bond Behaviour of Fabric Reinforced Cementitious Matrix Composites for Retrofitting Masonry Walls

Christis Chrysostomou,Fayu Wang,Renos Votsis,Eleftherios Eleftheriou,Nicholas Kyriakides,Rogiros Illampas

doi:10.1186/s40069-021-00460-1

Abstract

Fabric reinforced cementitious matrix (FRCM) composites, also known as textile reinforced mortars (TRM), an inorganic matrix constituting fibre fabrics and cement-based mortar, are becoming a widely used composite material in Europe for upgrading the seismic resistance of existing reinforced concrete (RC) frame buildings. One way of providing seismic resistance upgrading is through the application of the proposed FRCM system on existing masonry infill walls to increase their stiffness and integrity. To examine the effectiveness of this application, the bond characteristics achieved between (a) the matrix and the masonry substrate and (b) the fabric and the matrix need to be determined. A series of experiments including 23 material performance tests, 15 direct tensile tests of dry fabric and composites, and 30 shear bond tests between the matrix and brick masonry, were carried out to investigate the fabric-to-matrix and matrix-to-substrate bond behaviour. In addition, different arrangements of extruded polystyrene (XPS) plates were applied to the FRCM to test the shear bond capacity of this insulation system when used on a large-scale wall.

Highlights

1 Introduction Fabric reinforced cementitious matrix (FRCM) (AC434 I, 2013; ACI Committee 549, 2013) composites comprising an inorganic matrix of fibre fabrics and cement-based mortar are widely used in the retrofitting of existing reinforced concrete (RC) buildings
The tensile bond behaviour of FRCM composites is usually described by the stress–strain curve
(3) If the thermal insulation does not debond with the matrix, the tensile strength of the XPS plate may be converted to the matrix using a specific coefficient through the matrix-to-insulation bond mechanism, which will enhance the overall strength of the matrix as well as change the failure mode in the shear bond test

Summary

Introduction

Fabric reinforced cementitious matrix (FRCM) (AC434 I, 2013; ACI Committee 549, 2013) composites comprising an inorganic matrix of fibre fabrics and cement-based mortar are widely used in the retrofitting of existing reinforced concrete (RC) buildings. This system is generally known as textile reinforced mortar (TRM), and it is applied on different substrates for structural reinforcement. The selection of the appropriate materials and the corresponding bond mechanisms within layers forms the basis of further research which will help in building new retrofitting system for masonry walls

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Discussion

Conclusion