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Extreme hydrodynamic events, such as those driven by tsunamis, have a significant impact on coastal environments. The Smoothed Particle Hydrodynamics computational method gained popularity in modelling these phenomena. However, high resolution is needed in areas of interest, making coupling techniques popular to reduce computational costs. Herein, a new two-step offline coupling method was developed and validated in DualSPHysics. In step 1, the simulated velocity field and water depth are measured over a two-dimensional meshed surface of a generating domain. In step 2, the interpolated flow variables are used as boundary conditions in a receiving domain with equal or higher resolution. The method was validated by using two different laboratory experiments that are representative of tsunami propagation and inundation inland. The results show a reduction of computational time of up to 17.6 times, with decreasing savings for increasing resolution in the receiving domain. The validation tests showed that the developed method allows to simulate flows in the receiving domains at nearly the same accuracy of the generating domain while also decreasing computational time. When including debris transport, improvements in accuracy occur when doubling the resolution of the receiving domain with respect to the generating domain. This research was supported by grants from NVIDIA, United States and utilised NVIDIA RTX A6000 48GB. Dr. Corrado Altomare acknowledges funding from Spanish government and the European Social Found (ESF) under the programme ‘Ramón Cajal 2020’ (RYC2020-030197-I/AEI / 10.13039/501100011033). This work was partially supported by the project SURVIWEC PID2020-113245RB-I00 financed by MCIN/AEI/10.13039/501100011033 and by the project ED431C 2021/44 “Programa de Consolidación e Estructuración de Unidades de Investigación Competitivas” financed by Xunta de Galicia, Consellería de Cultura, Educación e Universidade, Spain. This study forms part of the Marine Science programme (ThinkInAzul) supported by Ministerio de Ciencia e Innovación and Xunta de Galicia with funding from European Union NextGenerationEU (PRTR-C17.I1) and European Maritime and Fisheries Fund .

This paper presents a numerical study on moisture transport in brick masonry walls with a special focus on the simulation of their hygric performance as well as the hydraulic phenomena at the brick-mortar interface. A diffusivity model based on Fick's law is used to describe the moisture transport accounting for both liquid and water vapor movement. The necessary hygric parameters are obtained directly from experimental tests or determined by curve fitting. The proposed model is validated with respect to water absorption and drying tests. The good-fitness of the results is qualitatively assessed and an overall good agreement is found between the simulated and measured curves. It is demonstrated that the chosen liquid water diffusivity expression needs to be adjusted to represent drying processes; the necessary adjustment is made through a diffusivity factor implemented in the original analytical expression. The interface impact on water absorption is introduced as a hydraulic resistance. Moreover, it is hypothesized that the presence of successive interfaces entails an additive in-series effect. Conversely, the interfacial impact on drying is negligible. Finally, the proposed model is extended to different modeling approaches commonly used for mechanical studies of masonry. The necessary input data, modeling methodology, advantages and disadvantages associated with each modeling strategy are also discussed. The present study points out the need of studying water absorption in multi-layered structures made up of constituents with relatively similar hygric behavior. In such cases, the impact of imperfect contact at the interface between materials is not negligible., Article publishing charge (APC) funded by agreement between Portugal (FCT/FCCN) and Elsevier

Within SERA Horizon 2020 INMASPOL project, the paper reports the first results from seismic tests on shake table for a real scale reinforced concrete (RC) frame building with modified orthoblock brick wall infills. The building received innovative protection using polyurethane resin (PU) flexible joints (PUFJ) at the frame-infill interface together with the use of PUs for bonding glass fiber grids to the weak masonry substrate, to form Fiber Reinforced PU (FRPU) as emergency repair. The tests validated the advanced in-plane and out-of-plane infill performance under suitably designed seismic excitations. The PUFJ protection enabled the quick repair of the infill even after very high inter-storey drifts of the structure. In addition, the applied glass FRPU repair system efficiently protected the damaged orthoblock infills against collapse under out-of-plane excitation while they restored large part of their in-plane stiffness as well. In this paper, the performances of the FRPU applications under simulated seismic excitations are reported.

This paper presents a multi-level experimental and analytical investigation on the mechanical performance of TRM composites used for strengthening existing masonry structures. Micro (fabric-to-mortar bond), meso (TRM-to-substrate bond), and macro (TRM tensile response and in-plane and the out-of-plane ressponse of TRM-strengthened masonry) response of TRMs are combined and investigated in-depth for this reason. These results help to understand the mechanisms controlling the response of these composites and their performance at the structural scale.

Due to the poor shear capacity of unreinforced masonry (URM) walls, it is necessary to strength these elements in the masonry structures. Textile-reinforced mortar (TRM) composites have received extensive attention as a sustainable solution for seismic strengthening of masonry and historical structures. This new system is composed of textile fibers embedded in an inorganic matrix such as lime-based mortar and is applied on the masonry substrate surface as an externally bonded reinforcement (EBR) system. Lime-based mortars are preferred for application to masonry and historical structures due to compatibility, sustainability issues, breathability and capability of accommodating structural movements.

The structural effectiveness of textile reinforced mortar (TRM) composites relies on their load transfer capacity to the substrate and the interaction between textile and mortar. The bond plays a crucial role in mechanism of TRM composites. Despite some recent investigations, a deep understanding still needs to be gained on the textile-to-mortar bond to develop suitable analytical and numerical predictive models, improve test methods, and orient design criteria. This work describes a laboratory study in which pull-out tests were carried out to investigate the effect of the slip rate and cyclic loading on the textile-to-mortar bond behaviour. Alkali-resistant glass fabric and sgalvanised ultra-high tensile strength steel cords embedded in two different lime-based mortars were tested. The pull-out response was sensitive to the strain rate at low rates. Cyclic loading produced a strength degradation, which reduced with the number of cycles.

This paper aims to provide a review of the current literature on the durability of textile-reinforced concrete and mortar (TRC/TRM) composites. Most previous studies have focused on the role of chemical attacks, freeze-thaw conditions, and high temperatures on the mechanical performance of these composites. Information on the long-term performance of TRCs under synergistic action of mechanical and environmental loads is scarce. Considering the variety of fabrics and matrices used for the production of TRC composites, the existing data are still very limited and comprehensive studies are needed in this field. Additionally, due to the lack of standard procedures, different approaches are often followed for durability or post-ageing mechanical tests, or sufficient data on the curing and post-ageing preparation procedures followed are not provided. These have led to incompatibility of the existing data and in some cases contradictory results on the durability of these materials., The support to the third author through grant SFRH/BD/131282/2017 is acknowledged.

Floods can transport debris of a very wide range of dimensions, from cohesive sediments to large floating debris, such as trees and cars. The latter increases the risk associated with floods by, for example, obstructing the flow or damaging structures due to impact. The transport of this type of debris and their interaction with structures are often studied experimentally in the context of tsunamis and flash floods. Numerical studies on this problem are rare, therefore the present study focuses on the numerical modelling of the flow-debris interaction. This is achieved by simulating multiple laboratory experiments, available in the literature, of a single buoyant container transported by a dam-break flow in order to validate the chosen numerical approach. The numerical simulations are carried using the open source DualSPHysics model based on the smoothed particle hydrodynamics method coupled with the multi-physics engine CHRONO, which handles the container–bottom interactions. The trajectory, as well as the velocity of the centroid of the container, were tracked throughout the simulation and compared with the same quantities measured in the laboratory. The agreement between the model and the experiment results is quantitatively assessed using the normalised root mean squared error and it is shown that the model is accurate in reproducing the floating container trajectory and velocity.

Current Topics and Trends on Durability of Building Materials and Components: Proceedings of the XV edition of the International Conference on Durability of Building Materials and Components (DBMC 2020), Textile-reinforced mortar (TRM) composites have received extensive attention as a sustainable solution for seismic strengthening of masonry and historical structures. This new system is composed of textile fibers embedded in an inorganic matrix and is applied on the masonry and the concrete substrate surface as an externally bonded reinforcement (EBR) system. The bond at the textile-to-mortar interfaces is the main stress-transfer mechanism and, therefore, should be thoroughly investigated. Furthermore, the effectiveness of TRMs in improving the seismic performance of existing structures is highly dependent on the durability of its components, materials, textile-to-mortar bond, and their long-term behavior. Due to the novelty of these materials in application to masonry structures, several aspects related to the durability and long-term performance of them are still not clear. To that end, a new study has been launched that looks at the time effect on the mechanical properties and bond behavior between fiber and mortar. For this purpose, two different hydraulic lime-based mortars, as well as steel and glass fibers, are used to investigate the effect of mortar age on the TRM system after 180 days. The results show that at the early age of mortars, their mechanical properties, and the bond behavior of textile-to-mortar have been increased. Another critical point to remember is that by increasing the mortar age, textile-to-mortar bond and mortar strength are decreased., FEDER funds through the Competitivity Factors Operational Programme (COMPETE) and by national funds through the Foundation for Science and Technology (FCT) within the scope of the project POCI-01-0145-FEDER-007633. The support to the first author through grant SFRH/BD/131282/2017 is acknowledged. Also, the authors would like to thank the Kerakoll Company for supplying the GeoCalce Fino mortar as well as GeoSteel G600 fibers

Application of textile-reinforced mortar (TRM) composites have for strengthening of existing structures or for production of new thin structural elements has attracted a growing recent attention. TRMs are made of continuous fibres (in the form of fabric or mesh) embedded in an inorganic matrix forming a composite material. The large variety of available fabric (glass, steel, basalt, PBO, etc.) and mortar types (cement-based, lime-based, etc.) leads to a wide range of mechanical properties making these composites suitable for fit-for-purpose design applications. Due to mechanical and hygrothermal compatibility issues, lime-based TRMs are the preferred choice for application to existing masonry and historical structures. Meanwhile, cement-based TRMs are usually employed for application to existing concrete or new masonry structures. The main characteristic behaviour of these composites is the tension stiffening response and distributed cracking under tensile loads which are highly influenced by the fabric-to-mortar bond behaviour. Fundamental understanding of this mechanism (the fabric-to-mortar bond behaviour) and parameters affecting that are therefore of critical importance of designing TRM composites with desired properties. This paper presents and overview of the recent studies we performed during the lat years for better udnertanding this mechanism., Portuguese Scientific Foundation (FCT) for the financial support through grant SFRH/BD/131282/2017

The paper reports the first results from seismic tests on shake table on a full scale reinforced concrete (RC) frame building with modified orthoblock brick wall infills, within INMASPOL SERA Horizon 2020 project. The building received innovative protection using polyurethane resin flexible joints (PUFJ) at the frame-infill interface, in different schemes. Further, PUs were used for bonding of glass fiber grids to the weak masonry substrate to form Fiber Reinforced PU (FRPU) as an emergency repair intervention. The test results showed enhancement in the in-plane and out-of-plane infill performance under seismic excitations. The results confirmed remarkable delay of significant orthoblock infill damages at very high RC frame inter-storey drifts as a consequence of the use of PUFJ. Further, the PUFJ protection enabled the repair of the infill even after very high inter-storey drift of the structure up to 3.7%. The applied glass FRPU system efficiently protected the damaged orthoblock infills against collapse under out-of-plane excitation while they restored large part of their in-plane stiffness.

Application of textile-reinforced mortars (TRMs) for externally bonded reinforcement of existing masonry structures has received a considerable recent attention. The mechanical behaviour of these composites, which are composed of continuous fibers embedded in an organic matrix, and their effectiveness in improving the performance of strengthened structures are highly dependent on the fiber-to-mortar bond behaviour as well as the bond between TRM system and substrate. Understanding the long-term performance of these mechanisms is therefore of critical importance for design of durable TRM composites and ensuring the safety of strengthened structures. To address this aspect, the effect of freeze-thaw cycles on the textile-to-mortar bond behaviour is experimentally investigated and discussed in this paper. The results illustrate a significant deterioration of the textile-to-mortar bond performance in the studied composites., FEDER funds through the Competitivity Factors Operational Programme (COMPETE) and by national funds through the Foundation for Science and Technology (FCT) within the scope of project POCI-01-0145-FEDER007633. The support to the first author through grant SFRH/BD/131282/2017

Aim of the present paper is to numerically investigate the bond behaviour of FRP strengthening systems externally applied on curved masonry specimens. In particular, considering the simple spring-model approach proposed by the authors in previous research, a new constitutive law derived from the work of Thorenfeld et al. (1987) is here proposed by also considering the coupled behaviour between shear and normal forces at the reinforcement/masonry interface. Numerical analyses are developed with reference to case studies deduced from the literature and consisting of shear lap bond tests of curved masonry specimens characterised by different values of the geometric curvature and different strengthening configurations. The obtained results show the ability of the proposed modelling approach in capturing some effects, such as the beneficial friction effect when compression normal stresses develop at the interface level.

A novel discretized homogenization strategy has been developed in order to deal with the analysis of masonry structures. In particular, unenforced and TRM reinforced masonry panels have been simulated under out-of-plane-loads The proposed method provides several advantages when compared with the already existing homogenization approaches. Bricks and mortar have been substituted by elastic cells linked by homogenized interfaces where the non-linear properties are lumped. Such interfaces are modeled as 8-noded 3D bricks along with a Concrete Damage Plasticity model, already available in Abaqus. In fact, the implementation at a structural level of the homogemzed properties results faster and easier. leading to major competitiveness and even ensuring the coupling of the in-plane and out-of-plane actions. The proposed strategy has been tested and validated by comparison with experimental references available in the literature and numerical references, provided by the authors, based on a micro-modeling approach. The results are highly satisfactory in the prediction of the damage pattern and of the global behavior of me analyzed masonry panels., (undefined)

Lime-based textile-reinforced mortars (TRM) have recently found a growing interest for repair and strengthening of masonry and historical structures. Despite extensive experimental and numerical investigations performed in the last years on the performance of these composites, there is still a lack of fundamental understanding of the fabric-to-mortar bond behaviour (as one of the main mechanisms affecting the cracking and nonlinear response of these composites) and the parameters affecting that. This paper, aimed at addressing this gap, presents a comprehensive experimental and analytical investigation on how the test setup, embedded length, load rate, mortar age and fabric configuration affect the bond behaviour in lime-based TRMs. In total 160 pull-out tests are performed on a glass-based and a steel-based TRM commonly used for strengthening of masonry structures. The results contribute to standardization of the test procedures for characterization of the fabric-to-mortar bond behaviour, to fundamental understanding of this mechanism and to optimization of the design of these composites for enhancing their mechanical response., This work was partly financed by FEDER funds through the Competitivity Factors Operational Programme (COMPETE) and by national funds through the Foundation for Science and Technology (FCT) within the scope of project POCI-01-0145-FEDER-007633. The support to the first author through grant SFRH/BD/131282/2017 is acknowledged.

This work addresses the reconstruction of strain gradient fields at the wood growth ring scale from full-field deformation measurements provided by digital image correlation. Moreover, the spatial distribution of the earlywood and latewood radial modulus of elasticity is assessed. Meso-scale tensile tests are carried out on Pinus pinaster Ait. wooden specimens oriented in the radial–tangential plane under quasi-static loading conditions. A parametric analysis of the two-dimensional digital image correlation extrinsic and intrinsic setting parameters is performed, in a balance between spatial resolution and resolution. It is shown that the parametric module is an effective way to quantitatively support the choice of digital image correlation parameters in the presence of the high deformation gradient fields generated by the structure–property relationships at the scale of observation. Under the assumption of a uniaxial tensile stress state, the spatial distribution of the radial elastic modulus across the growth rings is obtained. It is observed that the ratio of the radial modulus of elasticity between latewood and earlywood tissues can vary significantly as a function of the digital image correlation parameters. It is pointed out, however, that a convergence value can be systematically established. Effectively, earlywood and latewood stress–strain curves are obtained and elastic properties are determined assuming the converged digital image correlation setting parameters.

Textile reinforced mortars (TRMs) have emerged as a sustainable solution for strengthening existing masonry and concrete structures. As a result, many recent studies have focused on understanding the performance of these composites. However, most of these are aimed at investigating the mechanical properties of TRM composites. At the same time, their durability and long-term performance remain poorly addressed and unclear. This paper presents an experimental study on the effect of freeze–thaw environmental conditions on the micro-mechanical behavior of these composites. The results indicate that the freezing-thawing exposure conditions considered in this study do not have detrimental effects on the mortar strength. However, the fiber-to-mortar bond behavior can deteriorate because the deterioration level depends on the fiber type, embedded length, and fiber configuration.

This article presents an experimental study on the hygric performance of brick masonry with a special focus on the hydraulic characterization of the brick-mortar interface. The hygric behavior was studied at the level of the constituent materials as well as at the composite scale. An extruded fired-clay brick and two types of mortar –Portland cement mortar and natural hydraulic lime mortar– were chosen as target materials. The hygric properties were determined following prescribed experimental procedures. The experimental program included vacuum saturation tests, static gravimetric tests for adsorption/desorption isotherms, dry/wet cup tests, capillary absorption tests, and isothermal one-dimensional drying. The results allowed for a comprehensive identification of the main hygric features of the target materials. Fired-clay brick and lime mortar revealed low hygroscopicity and a strong capillary-active behavior with negligible hysteresis, whereas cement mortar showed activity in both hygroscopic and capillary ranges with a distinct moisture storage hysteresis. Different curing conditions led to dissimilar properties between the lime mortar prepared in molds and the same mortar cured in masonry bed joints. Water absorption in fired-clay bricks showed a marked anisotropic behavior, likely derived from the extrusion process. The existence of an imperfect hydraulic contact at the brick-mortar interface was demonstrated for water absorption. Conversely, the interfacial effect on drying kinetics was not evident.

Reliable design and application of textile-reinforced mortar (TRM) composites for the repair of existing masonry and concrete structures requires a fundamental understanding of the textile-to-mortar bond behavior as one of the main mechanisms controlling their nonlinear response and cracking behavior. Suitable test setups and analytical models are needed to extract the bond-slip laws from the experimental pull-out tests. This paper proposes a new bond-slip law and analytical model, which predicts the bond behavior of lime and cement-based TRM composites considering the slip hardening and softening effects observed in experimental tests. For this purpose, the pull-out response of experimental specimens with different fiber types (steel and glass), bond lengths, and mortar age are analyzed, and their bond slip-laws are extracted. The accuracy of the developed model is shown by comparing analytical and experimental results.

The paper deals with the analysis of FRCM reinforced masonry panels in simple bending by means of a two-step homogenization approach. In the first step, homogenization is performed on unreinforced masonry through a straightforward procedure already validated for in-plane loaded FRCM reinforced panels, where the elementary cell is discretized by means of 24 CST elastic elements (bricks) and joints are reduced to interfaces with holonomic softening behavior. Out-of-plane homogenized quantities (moment-curvature relationships) are then obtained by simple on-thickness integration. At a structural level (step two), masonry is modeled with rigid elements and homogenized torsional and bending springs, whereas FRCM by two noded trusses with equivalent mechanical properties evaluated on the base of experimental data available. The implementation is handled within the commercial FE software Abaqus. As a matter of fact, the Concrete Damage Plasticity Model (CDP) already implemented into the code allows taking into account the progressive change of stiffness of brittle supports when subjected to alternate cracking-crushing mechanisms, as well as to properly deal with the cyclic behavior. The validation of the procedure is conducted against a series of full scale masonry walls tested by Nanni and co-workers at the University of Miami. A tri-dimensional heterogeneous micro-modeling technique is also used for both unreinforced and FRCM strengthened panels to further validate the homogenization model proposed. The discretization adopted is adjusted in order to allow the presence of two eight-noded FEs along the mortar joint thickness. FRCM is modeled by means of truss elements whose mechanical properties are calibrated to reproduce the behavior of the textile net embedded into the cementitious matrix. The elastic and inelastic mechanical parameters of all the materials involved into the numerical analyses have been calibrated in agreement with laboratory tests, when available. Pros and cons of the two numerical strategies are discussed mostly with respect to the accuracy of the outcomes in terms of global behavior of the panels and damage mechanisms, as well as with respect to the computational effort required by the two approaches to complete the analyses.

[Excerpt] 17.1 Introduction Fiber-reinforced polymers (FRPs) have been extensively used for seismic strengthening of existing concrete and masonry structures. The ease of application and high strength-to-weight ratio of these composites have made them an interesting solution for strengthening purposes.[...], (undefined)

Fabric-reinforced cementitious matrix (FRCM) strengthening is an innovative technology for effective reduction of seismic vulnerability of existing masonry and historical structures. At present, numerical modeling strategies for evaluation of the in- and out-of-plane performance of masonry structures strengthened with these composites are in their embryonic stage. The present chapter is aimed at presenting two alternative approaches to such strategies. In particular, a detailed 3D heterogeneous and an inexpensive homogenization approach are reviewed. In the first model, brick and mortar joints are meshed separately with 3D eight-noded elements, whereas FRCM is discretized using trusses (fiber grid) and 3D eight-noded elements (cementitious matrix). These 3D elements are made in all cases with a softening and damage behavior with plasticization, both in tension and compression, using the concrete damage plasticity model. In the homogenization approach, masonry is substituted with an equivalent nonlinear orthotropic material exhibiting softening. The elementary cell is discretized using a few triangular elastic elements (bricks) and holonomic interfaces (joints) in which all the nonlinearities are lumped. The FRCM reinforcement is applied to the homogenized masonry using equivalent trusses with limited tensile strength and fragile behavior, connecting adjoining rigid elements. Equivalent mechanical properties of the trusses can be eventually tuned accounting for FRCM debonding or rupture of the fibers. The pros and cons of the two numerical procedures are discussed with respect to their reliability in fitting experimental force–displacement curves and crack patterns, as well as to the rather different computational effort required by the two strategies.

The strengthening of masonry structures using composite-based solutions has received significant research attention in recent years due to their proved considerable influence on enhancing structural characteristics, for example, stiffness and strength. In spite of the all achieved advances, numerous drawbacks have been noticed, in particular when conventional fiber-reinforced polymers are used. Thus novel techniques such as textile-reinforced mortar (TRM) have been introduced to overcome these issues. This chapter addresses key aspects of nonlinear finite element modeling of TRM composites. It mainly discusses the macromodeling approach as it requires fewer details (material characteristics) and less computational effort with respect to the micromodeling strategy, making it possible to use this approach in complex practical projects. Experimentally observed behaviors and characterization of required material properties are considered and knowledge gaps are highlighted. Finally, a series of numerical macromodeling applications on masonry structures are discussed, involving different construction materials. Pushover analyses are conducted to assess the influence of TRMs on both in-plane and out-of-plane seismic responses, (undefined)

Numerical Modeling of Masonry and Historical Structures: From Theory to Application provides detailed information on the theoretical background and practical guidelines for numerical modeling of unreinforced and reinforced (strengthened) masonry and historical structures. The book consists of four main sections, covering seismic vulnerability analysis of masonry and historical structures, numerical modeling of unreinforced masonry, numerical modeling of FRP-strengthened masonry, and numerical modeling of TRM-strengthened masonry. Each section reflects the theoretical background and current state-of-the art, providing practical guidelines for simulations and the use of input parameters. Covers important issues relating to advanced methodologies for the seismic vulnerability assessment of masonry and historical structuresFocuses on modeling techniques used for the nonlinear analysis of unreinforced masonry and strengthened masonry structuresFollows a theory to practice approach