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[Display omitted] • Presents a cost-effective method for improving the behaviour and mechanical properties of stone masonry set in mud mortar. • Presents mechanical properties of stone masonry set in mud mortar and contained by steel wire mesh. • Presents cycle performance of stone masonry set in mud mortar and contained by steel wire mesh. • Compares the performance of unreinforced stone masonry with stone masonry contained in steel wire mesh. • Fills in current data gap on stone masonry construction. The mechanical properties of semi-dressed stone masonry set in mud mortar and contained within steel wire mesh are reported. Two-wythe thick masonry was laid in a semi-layered configuration as is typically found in the earthquake-affected areas of the 2015 Gorkha (Nepal) earthquake. An experimental testing program was undertaken that included direct compression, diagonal tension (shear), and in-plane quasi-static cyclic shear tests of masonry wallettes that were both uncontained (without containment mesh) and contained (with containment mesh). The results of the experimental testing indicated that the provision of containment enhanced the strength, deformability, and energy dissipation capacity of the masonry. Findings from the experimental testing are presented, including a comparison of the performance of stone masonry set in mud mortar when either uncontained or contained. [ABSTRACT FROM AUTHOR]

• Efficacy of a low-cost strengthening method embedded in the bed and bed-head joint mortar of a low-strength masonry assemblage. • Unreinforced and reinforced specimens were tested under axial compression load. • Bed joint and bed-head joint embedding play a vital role in the performance of the strengthened masonry. • Bed-head joint embedding outperforming bed joint and URM masonry. Masonry buildings are the most common building type in Northeast India. For the last 4–5 years, low strength Autoclaved Aerated Concrete (AAC) blocks have been widely used in most new construction. Masonry buildings are fragile and sustain significant damage when subjected to seismic excitation due to their low tensile strength and lack of earthquake-resistant features. Steel wire mesh is a low-cost, readily available material that is commonly adopted to strengthened unreinforced masonry by wrapping the entire surface of the wall. However, it is very un-economical in large scale construction. Embedding steel wire mesh to the bed and bed-head joint mortar of low-strength masonry units, such as AAC, has received little attention and possibly act as an earthquake-resistant feature in masonry buildings. The present study attempts to investigate the compression behaviour of AAC masonry walls when embedding three different types of steel wire mesh. The steel wire mesh was embedded using two methods, i.e., embedding steel wire into the masonry bed joint and the masonry bed-head joint. Three strengthening configurations were adopted for both the method and all three types of steel wire mesh, i.e., (−) straight configuration, L configuration, and Z configuration. The test result indicated that the inclusion of steel wire mesh in the masonry bed joint and bed-head joint enhanced the failure patterns, axial load-carrying capacity, stiffness, ductility, and energy dissipation for both strengthening methods, with bed-head joint specimens outperforming bed-joint and URM masonry. [ABSTRACT FROM AUTHOR]

Unreinforced masonry (URM) is the oldest construction technique. URM being brittle cannot withstand the lateral loads during earthquake, hence it is necessary to find a suitable cost effective technique to strengthen masonry buildings in order to resist earthquake loads without causing any damage to life. In this paper, an attempt has been made to strengthen the URM samples of high strength mortar (1 cement : 4 sand) and low strength mortar (1 cement : 6 sand) which are commonly used in Indian construction practice, using mortar (1 cement : 3 coarse sand) and welded wire mesh (WWM) of various spacing (25 mm, 38 mm, 50 mm) which are locally available in market. A series of 6 URM panels and 18 reinforced masonry panels have been tested under three-point loading method as per ASTM E518-10 recommendations to study the out-of-plane behaviour of both URM and WWM mortar reinforced masonry. The mode of failure and behaviour of masonry have been investigated in terms of strength, stiffness and ductility. The results show that strengthening of masonry using WWM enhanced the flexural strength and ductility of masonry. [ABSTRACT FROM AUTHOR]

Abstract: Experimental and analytical investigations for the modulus of elasticity of thin cement composite composed of mesh and mortar are demonstrated. Based on the analyses and experimental data, new equations for the modulus of elasticity of thin cement composite are proposed. It is observed that the flexural modulus of elasticity of thin cement composite depends on the elastic modulus of mortar and some factor of the difference of elastic modulus of mesh and mortar. Results obtained by using the proposed equations are compared to those of the available equations. It has been found that the newly developed equations give relatively conservative results as compared to the typically used ones. A comparison between the analytical and experimental findings further indicates that there is a good agreement between the analytical and experimental results. [Copyright &y& Elsevier]

• Out-of-plane bending of low-strength hollow concrete block masonry wall specimens strengthened with welded wire mesh (WWM). • Three different mortar grades for bonding the masonry units, were used to construct the masonry walls. • No marked effect of mortar strength on unstrengthened specimens. • Increase in flexural strength and ductility of strengthened specimens with increase of mortar strength. The present study aims to understand the effect of mortar grade for bonding the masonry units, on the out-of-plane flexural behaviour of low-strength hollow concrete block masonry walls strengthened with welded wire mesh (WWM). Static out-of-plane flexural tests were performed on unstrengthened and WWM-strengthened specimens constructed with three different mortar grades representing strong, medium and weak mortar. It is observed that mortar strength do not have any profound effect on the flexural strength of unstrengthened specimens. The increase in mortar strength increases the flexural strength and ductility of WWM-strengthened specimens. However, there is insignificant difference in ductility between medium and strong mortared WWM-strengthened specimens. The failure of WWM-strengthened specimens is restricted to the masonry walls only suggesting overstrength of WWM. The comparison of experimentally evaluated flexural strength is also compared with existing analytical formulations displaying good agreement between experimental and analytical formulations. [ABSTRACT FROM AUTHOR]

• Effectiveness of WRCM for strengthening of low-strength masonry assemblages. • Series of tests done to assess flexure and shear response of small-size specimens. • Properties of matrix play a vital role in the performance of strengthened masonry. • Study suggest to use suitable type of wire mesh and anchor for better performance. The wire reinforced cementitious matrix (WRCM) was used to improve the in-plane and out-of-plane performance of weak masonry assemblages. Six different types of WRCMs were used to strengthen small-size masonry assemblages and to understand the role of various parameters such as tensile strength of welded wire mesh, compressive strength of masonry and cementitious matrix in influencing the efficiency of the strengthening scheme. An experimental program consisting of diagonal compression and four-point bending test was conducted to evaluate the in-plane (shear) and out-of-plane (flexural) strength of strengthened masonry assemblages. Two types of low-strength mortar; 1:6 cement-sand, and mud mortar was used to prepare the masonry specimens. A total of 120 specimens with 40 specimens each for the diagonal compression test and flexure test with failure plane-parallel and perpendicular to the bed joint were prepared and tested under quasi-static displacement control loading. Test results showed that the WRCM strengthening scheme is effective and can significantly enhance the shear, and flexural strength and ductility of low-strength masonry assemblages. This study illustrates that the strength of cementitious matrix can also play an important role in contributing to the flexural and shear behavior of the WRCM strengthened masonry. Further, the experimental results were compared with theoretical predictions estimated using the available analytical models. [ABSTRACT FROM AUTHOR]

• Unreinforced masonry with horizontal hollow clay bricks was strengthened. • Specimens were tested under compression and diagonal compression loads. • Mortar overlay reinforced with welded-wire mesh improves the performance of panels. • Transverse connectors increase mechanical properties of strengthened panels. • Steel fibers added to mortar reduce crack width and increase ductility of panels. The performance of unreinforced Masonry (URM) and strengthened masonry panels built with horizontal hollow clay bricks is assessed in this article. The strengthening method consisted of an external mortar overlay reinforced with two different steel ratios of welded wire mesh (WWM), two configurations of transverse connectors, and steel fibers in one of the specimens. The URM and strengthened masonry panels were tested under axial compression, and under monotonic and cyclic diagonal compression. The experimental program includes the tests of 31 specimens: 10 URM specimens, and 21 strengthened specimens. Results evidenced that WWM and transverse connectors enhance the performance of strengthened masonry panels. Measured results also demonstrate that strengthening of URM panels increases compression and shear strength, ductility and energy dissipation capacity. The proposed strengthening layout can be used to retrofit URM houses. [ABSTRACT FROM AUTHOR]

• It comprises relatively high strength steel, high strength steel wire mesh and MHSM. • This composite improves the load carrying capacity, ductility and post peak behavior. • Relationship of strength increment and effective confinement pressure is assessed. • A comparison between the proposed models and other models is presented. This paper presents an investigation on the axial compression behaviour of concrete strengthened with an innovative composite, which comprises relatively high strength steel rings, wire mesh and modified high strength mortar (MHSM). In total, 38 cylindrical specimens divided into three groups were tested. The parameters studied are the ring spacing and the number of mesh layers. The results show that this composite can effectively improve the load carrying capacity, deformation capacity, ductility and energy absorption of the strengthened concrete specimens. The axial compression behaviour is predominantly governed by steel rings. As a secondary confinement, wire mesh markedly enhances ductility. The results indicate that MHSM has significant influence on the ultimate load and concrete strengthened with sufficient amount of wire mesh is potentially comparable to that with a low steel volumetric ratio. It was observed that steel rings did not reach the yield stress at the second peak load. Different models for predicting the ultimate load are discussed. The proposed empirical models provide prediction with reasonable accuracy. [ABSTRACT FROM AUTHOR]