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The existing infilled reinforced concrete (RC) buildings' poor energy performance is responsible for a significant part of the energy consumption in the European Union (EU). In addition, recent earthquakes showed the seismic vulnerability of the existing RC buildings that were not designed according to modern codes, where several casualties, collapses, and economic losses were reported. Around 40% of the EU buildings are located in seismic regions and designed with substandard safety requirements, of which 65% need both energy and seismic retrofit. New strategies are necessary to simultaneously improve the energy efficiency and seismic vulnerability of new constructions. Apart from the modern seismic and energy codes, new materials are being developed by the construction industry that can play a significant role in the next few decades. Based on this motivation, this paper aims to study the efficiency of using textile-reinforced mortar (TRM)-based solutions to improve the seismic behavior of masonry infill walls made of lightweight and energy-improved masonry blocks. This holistic strategy is designed for new constructions. For this, eight strengthened energy-improved infill walls were subjected to flexural strength tests to validate the TRM efficiency using a low-strength and a high-strength textile mesh and study the effect of using connectors. All the tests consisted of applying a monotonic out-of-plane tests were performed through a one-point load approach. The results will be presented in terms of out-of-plane force–displacement responses, flexural stress, and damage evolution. Lastly, a state-of-the-art discussion is carried out to analyze possible relationships between the textile mesh tensile strength and the flexural strength of the walls. [ABSTRACT FROM AUTHOR]

Stone masonry is one of the oldest and most worldwide used building techniques. Nevertheless, the structural response of masonry structures is complex and the effective knowledge about their mechanical behaviour is still limited. This fact is particularly notorious when dealing with the description of their out-of-plane behaviour under horizontal loadings, as is the case of the earthquake action. In this context, this paper describes an experimental program, conducted in laboratory environment, aiming at characterizing the out-of-plane behaviour of traditional unreinforced stone masonry walls. In the scope of this campaign, six full-scale sacco stone masonry specimens were fully characterised regarding their most important mechanic, geometric and dynamic features and were tested resorting to two different loading techniques under three distinct vertical pre-compression states; three of the specimens were subjected to an out-of-plane surface load by means of a system of airbags and the remaining were subjected to an out-of-plane horizontal line-load at the top. From the experiments it was possible to observe that both test setups were able to globally mobilize the out-of-plane response of the walls, which presented substantial displacement capacity, with ratios of ultimate displacement to the wall thickness ranging between 26 and 45 %, as well as good energy dissipation capacity. Finally, very interesting results were also obtained from a simple analytical model used herein to compute a set of experimental-based ratios, namely between the maximum stability displacement and the wall thickness for which a mean value of about 60 % was found. [ABSTRACT FROM AUTHOR]

• The effect of seismic plus energy retrofitting techniques on the flexural strength of full-scale masonry brick walls. • Nine full-scale specimens were built where three were built without retrofitting. • The proposed retrofitting techniques can significantly improve the flexural strength of masonry brick walls. The article presents the results of a testing campaign that was carried out to validate the effect of ETICS and seismic plus energy retrofitting techniques on the flexural strength of full-scale masonry brick walls. The study highlights the importance of retrofitting techniques that can improve the energy efficiency and seismic safety of existing buildings, a growing global concern. Based on this motivation, a testing campaign was carried out to validate the effect of ETICS and seismic plus energy retrofitting to improve the flexural strength of full-scale masonry brick walls. For this, nine full-scale specimens were built where three were built without retrofitting, three with ETICS and the remaining three retrofitted with a combined retrofitting technique. Each test involved applying OOP quasi-static uniform load simultaneously at the top and bottom of each wall to reach the collapse. Also, the accuracy of prediction models for non-retrofitted and retrofitted walls will be assessed. The results indicate that retrofitting techniques can significantly improve the flexural strength of masonry brick walls, with combined retrofitting techniques showing promising results for seismic strengthening. The strength and deformation capacity improved high than 200%. [ABSTRACT FROM AUTHOR]

• Experimental tests on TRM-strengthened infilled frames under OOP loading. • Analysis of dynamic properties of the TRM-strengthened infills. • Comparison of response with and without IP damage and with and without strengthening. • Database of experimental tests on TRM-strengthened infilled frames under OOP loading. • Analysis of predictive equations for OOP strength of TRM-strengthened infills. In existing Reinforced Concrete (RC) buildings, the out-of-plane (OOP) collapse of masonry infills can be a significant issue for resulting damage and life safety in case of earthquake. Quite recently, research works from the literature have studied possible strengthening strategies to reduce the vulnerability of the infill panels due to OOP loading. Among these techniques, the use of Textile Reinforced Mortars (TRM) as an innovative reinforcing plater has rapidly become very popular, due to its good compromise between costs of intervention and effectiveness, along with its durability properties. Nevertheless, still quite few studies exist on this topic to experimentally prove the TRM effectiveness on masonry infills, above all in case of pre-existing in-plane (IP) damage. Even fewer studies in the literature are currently devoted to the prediction of the OOP strength of TRM-strengthened infills, despite the necessity to quantify the beneficial effect of the strengthening solution in a force-based safety check. This work shows the experimental outcomes of four full-scale infilled frames under OOP loading, with or without a TRM-based strengthening technique and with or without previous IP damage. First, a look insight the effect on dynamic properties of the TRM strengthening strategy is reported and commented. Then, the (cyclic) IP and (half-cyclic) OOP pseudo-static testing results are shown and compared to each other to analyze the effect of the IP damage on the OOP response with and without strengthening. Lastly, the very few predictive proposals for OOP strength of TRM-strengthened specimens have been analyzed, based on a dedicated collected database, to lastly provide some suggestions for future design tools for TRM applications on infills. [ABSTRACT FROM AUTHOR]

• Out-of-plane tests of infill masonry walls with concrete blocks. • Assessment of the impact of previous damage. • Analysis of the effectiveness of using TRM strengthening to improve the OOP behaviour. • Tested walls results were compared with data available in the literature with different masonry units. Masonry infill walls are widely spread over the reinforced concrete buildings due to different demands. The buildings' thermal energy efficiency is a top priority nowadays since many of the existing building stock comprises buildings with low energy performance. The buildings' external envelope is undergoing a transformation with the vertical hollow concrete blocks' appearance with high thermal and acoustic demands. However, recent evidence from a strong earthquake shows that the masonry infill walls are quite vulnerable to out-of-plane loadings and were responsible for many casualties, injuries and economic losses. Based on that, this work's main objective is to study the out-of-plane (OOP) behaviour of masonry infills made with vertical hollow concrete blocks. The experimental campaign comprises the OOP testing of three full-scale infill walls made up of these masonry units, one of them as-built without previous damage, one with previous damage due to an earlier in-plane test and the third one retrofitted. All the tests consisted of applying the loading–unloading-reloading history of imposed displacements in the OOP direction through a uniformly distributed load. The results will be presented in terms of OOP force–displacement responses, damage evolution and energy dissipation capacity. The test results are compared to assess the previous damage effect and the retrofit technique's effectiveness. A final study is presented concerning the masonry unit and slenderness effect with other literature results. [ABSTRACT FROM AUTHOR]