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In this paper, the first‐principles method is used to calculate the electronic structure of the intrinsic WSe2 system and the Ca adsorbed WSe2 system under shear deformation, and the diffusion barrier of Ca on WSe2 is studied in depth. The results show that shear deformation can effectively reduce the band gap of WSe2 system, and shear deformation can easily lead to the transition from semiconductor properties to metal properties. The adsorption of Ca leads to the change of the band structure of WSe2. The contribution of Ca‐d electrons leads to an increase in the peak in the range of 3–6 eV. The shear deformation reduces the diffusion barrier of Ca on the WSe2 surface. This paper provides an improvement method for the application of WSe2 in the field of battery. [ABSTRACT FROM AUTHOR]

Summary: H‐shaped circular arc is a relatively novel type of open‐web steel arch, and currently, no reports have been published concerning its in‐plane stability. In this paper, the elastic and elastic–plastic in‐plane stability of the H‐shaped hollow circular arch is studied by theoretical deduction combined with numerical simulation. First, the overall shear rigidity of the H‐shaped circular arch is calculated, and the elastic buckling load formula of the arch is proposed and verified considering double shear deformation under full‐span radial and uniform loading. The overall elastic buckling load deduced in this paper is reasonable according to the finite element analysis. The results indicate that the influence of shear deformation on the overall elastic buckling load of the arch decreases with the increase of the span length. The arch‐bearing capacity is the largest when the rise‐span ratio is 0.25. Second, the restriction conditions necessary for avoiding local buckling of the chordal web before integral buckling of the H‐shaped steel hollow circular arch are analyzed. Finally, the elastic–plastic failure mechanism of the H‐shaped arch under full‐span radial and uniform loading is examined, and the formula for determining the ultimate bearing capacity that is achievable before failure under full‐span radial and uniform loading is proposed. ANSYS analysis shows that under the radial uniform loading, the chordal bars will yield near 1/4L and 3/4L, and ultimately, the structural failure of the lower chord occurs in the vicinity of 1/4L. The formulas presented in this paper agree well with the results obtained from the finite element analysis and can be used as a reference for engineering applications. [ABSTRACT FROM AUTHOR]

Highlights Textile composites are advanced materials composed of preforms combined with matrix materials. The fiber structure in the preform has a significant impact on the mechanical properties of the composite. Precise control over preform dimensions and internal fiber structural uniformity, termed ‘accurate shape control’, is essential to ensure reliable and stable composite component mechanical properties. This paper reviews current research progress on fabric deformation mechanisms, focusing on experimental characterization and numerical simulation. Experimental methods for fabric deformation include tensile, compression, bending, and shear deformation, whereas numerical methods encompass macroscopic continuum, discrete, and semi‐discrete models. The insights offered in this paper will aid a greater understanding of fabric deformation mechanisms, enabling an accurate prediction of complex shape molding and effective process parameter design, ultimately facilitating the structural design and engineering applications of textile composites. Recent trends and challenges in the study of fabric deformation mechanisms are presented. The experimental methods for fabric deformation were summarized and evaluated. Representative numerical modeling techniques and simulation methods are discussed. Some recommendations on potential future research directions are detailed. [ABSTRACT FROM AUTHOR]

Nominated for the Eurosteel 2021 Best Paper Award This short report has been prepared in the context of the Eurosteel 2021 Best Paper Award. It summarizes developments completed and in progress at the University of Liège designed to characterize the complete shear behaviour of the panel zone in steel beam‐to‐column joints in terms of stiffness, resistance and ductility. This work is part of a larger research project which aims to predict the complete rotational response of the joint to failure. [ABSTRACT FROM AUTHOR]

Small amounts of shear reinforcement are often assumed to increase the shear capacity of RC beams, compared to an identical beam without shear reinforcement. However, in a recent experimental campaign, the shear capacity of beams with a shear reinforcement ratio below the minimum requirements according to the design standards turned out to be similar to identical beams without shear reinforcement. This paper presents a detailed analysis of why the shear capacity may be similar for beams without‐ and beams with small amounts of shear reinforcement. This includes the influence of small amounts of shear reinforcement on the shear behaviour and shear‐transferring mechanisms. The analysis shows that the crack development is more severe at the ultimate load for beams with a small amount of shear reinforcement compared to beams without shear reinforcement. This more severe crack development is shown to cause an overestimation of the shear contribution from aggregate interlock when applying a well‐known constitutive model often used for beams without shear reinforcement. Therefore, a new expression for the aggregate interlock stresses is proposed. A comparison of the proposed expression with Mixed‐Mode crack opening tests shows a good agreement with the test for both small and large crack openings. By applying the proposed expression on the measured crack kinematics it is shown that for a large shear contribution from aggregate interlock the shear contribution from the shear reinforcement is very limited and as the aggregate interlock stresses decrease the shear contribution from the shear reinforcement increases. This shift in the governing shear‐transferring mechanism can help to improve the requirements for the minimum shear reinforcement often found in the design standards. [ABSTRACT FROM AUTHOR]

As members of Project Team SC4.T5, the authors of this paper present the main outcomes from the work that is intended for implementation within the second generation of Eurocode 4. General design and application rules for composite design of precast concrete elements will be presented, with a particular focus on: the effective width of flanges using precast concrete elements for shear lag; design resistance to longitudinal shear; and the design resistance of headed stud connectors in the presence of precast hollow core slabs. [ABSTRACT FROM AUTHOR]

In this paper, the in‐plane shear deformation of unbalanced 3D interlock woven reinforcement (IWR) was investigated through experiments and finite element modeling. Five specimens with five layers warp (six layers weft) were designed and prepared. The warp is 792 tex carbon tows and weft is 396 tex carbon tows. This kind of reinforcement is unbalanced because that the linear density of warp is different from that of weft. The in‐plane shear deformation of unbalanced 3D IWR was tested by bias extension test. The bias extension process was simulated by finite element method from macro and meso scales. The results of simulation are basically consistent with experiments. The bias extension process can be divided into three stages: Meso scale deformation stage, multiscale deformation stage and Reinforcement failure stage. At meso scale deformation stage, the tensile load and shear angle are small when the displacement is less than 7.5 mm. There is no obvious change in the macro scale, while the weft slipping in the meso scale mainly occurs in area B. The deformation of B1 and B2 are asymmetric because the linear density of warp is different from that of weft. In the multiscale deformation stage, asymmetric deformation at the macro scale begins to appear when the displacement is between 7.5 mm and 20 mm. There is obvious in‐plane shear deformation in area C at the meso scale. In the reinforcement failure stage, A large number of weft yarns are pulled out from the reinforcement in area B. [ABSTRACT FROM AUTHOR]

The application of trapezoidal corrugated plate as the web for girders, thanks to a number of favorable features, modernizes the manufacture of steel‐concrete composite and hybrid structures and provides an alternative, competitive structure for small, medium and large span beams. However, the traditional headed stud shear connectors on the top flange can be considered obsolete in many ways. By embedding the corrugated steel web to the concrete slab, other types of connections should be used, and the behavior of these kind of connections are really promising. In fact, the embedded corrugated web itself functions as a shear connector, though other additive connectors should be used. To understand the structural behavior and design of these embedded connectors, the first step is the examination of the embedded web. The focus of the research presented in this paper is on the interaction behavior of embedded trapezoidal corrugated webs with additional mechanical shear connectors. As the first steps of the research comprehensive experimental program was completed in the Structural Laboratory of the Department of Structural Engineering in BME. This paper provides an overview for 8 (test) 12 (FE model) specimens of the push‐out test program with the aim to introduce the structural behavior of embedded corrugated steel web and the influence of structural parameters on the shear resistance and deformation capacity through experimental and numerical investigations. [ABSTRACT FROM AUTHOR]

The mechanical response of granular materials, exemplified by frictional grain interactions, is characterized by a critical state in which deformation occurs without change of material volume or stresses when subjected to large shear deformation. In this work, a granular micromechanics approach (GMA) based continuum model is used to investigate the emergence of such a critical state. The continuum description is constructed through mechanical concepts based upon elastic and dissipation energies defined for a generic grain‐pair interaction. A hemivariational principle provides the basis for considering the evolution of damage and plasticity phenomena comprising grain‐pair contact loss and irreversible deformation. As a consequence, the Karush–Kuhn–Tucker (KKT)‐type conditions are derived, which give the evolution equations for the irreversible phenomena. Notably, in this derivation there is no invocation of flow rules and other similar assumptions of classical phenomenological continuum damage and plasticity. Further, Piola's ansatz is elaborated to kinematically connect granular micromechanics of grain‐pair to the continuum description. While the concept of critical state analysis has been handled with either phenomenological approaches or discrete numerical frameworks, in the present paper this concept is examined within a micromechanics‐based continuum description. The constitutive model is established and the coupled damage and plastic irreversible quantities are assessed. The critical state is shown to emerge as grain‐pair related damage and plastic evolution in a competitive/collaborative manner during the imposed loading path. [ABSTRACT FROM AUTHOR]

As part of optimizing a steel composite section to determine whether longitudinal stiffeners could be omitted concerning plate buckling, a buckling tool was developed that implements both the effective width method (EWM) and the reduced stress method (RSM). These two methods are offered in addition to the finite element method in EN 1993‐1‐5 for buckling analysis. It was found that when using the formula given in EN‐1993‐1‐5 for calculating the critical buckling stress of unstiffened buckling fields, which is independent of the acting stress distribution, the ratio of the elastic critical plate buckling stress to the elastic critical column buckling stress (σcr,p/σcr,c) is underestimated if the compressive stress is not uniform. This affects the detection of column buckling behavior. The most economical variant resulting from the optimization, the buckling tool, the influence of shear deformations combined with plate buckling, and the column buckling behavior of unstiffened buckling fields are presented in this paper. [ABSTRACT FROM AUTHOR]

In this paper, a numerical critical shear crack model, in which the shear‐flexural coupling effect is considered and the full process of stress and strain is captured, is proposed to evaluate the post‐peak behavior of reinforced concrete (RC) and steel fiber reinforced concrete (SFRC) beams. The shape of critical shear crack is identified by combining the modified compression field theory considering the bridge effect of steel fibers and the section analysis method. Based on the shape of critical shear crack, the shear capacity of beam members is provided by the shear tension zone and the shear compression zone. The shear capacity of the shear tension zone is calculated by the modified compression field theory and that of the shear compression zone is determined by multiaxial strength criterion of concrete. The vertical displacements caused by the flexure deformation and shear deformation are deduced by the moment area method and integration of shear strain. To verify the proposed numerical approach, a test database of 486 RC beams and 313 SFRC beams was established to predict the shear strength, and the force‐displacement relationships of twelve beam members are used to validate the feasibility for full process analysis. The stochastic analysis of beams with different failure modes is conducted via GF‐discrepancy‐based point selection method and probability density evolution method. The limitation between different failure modes is defined according to the degradation percent of shear capacity and it is taken as threshold value of failure domain, and the failure probability analysis indicates that the designed flexure beam member suffered severe degradation of shear capacity, resulting in a significant decline in safety probability. [ABSTRACT FROM AUTHOR]

This paper uses the analytical method with arbitrary boundary conditions to model and analyze the free vibrations of multi‐directionally functionally graded porous (MFGP) doubly‐curved shallow shells resting on the Pasternak foundation in a temperature environment. It is anticipated that all mechanical parameters, except Poisson's ratio, will change in the direction of length, width, and thickness. To comprehensively describe the shell's displacement, strain, and stress fields, a modified first‐order shear deformation theory (FSDT) with an assumption of cosine distribution shear stresses has been developed. The fact that the enhanced FSDT theory does not require the use of shear correction and that the shear stress at the two free faces of the shells is zero are two of the theory's most significant advantages. Using Hamilton's principle and improved FSDT, one may get the governing equation for free vibration analysis of MFGP doubly‐curved shallow shells. The Galerkin approach is proposed to solve the governing equation of MFGP doubly‐curved shallow shells with various boundary conditions. The trustworthiness of the article is evaluated via its publication in the article model's several special cases. From this point on, a collection of findings about the natural frequency of MFGP doubly‐curved shallow shells is identified and shown in the form of tables and graphs. The results provided in this manuscript can be used as a benchmark solution for further studies as far as the vibration behavior of the MFGP doubly‐curved shallow shells is concerned. [ABSTRACT FROM AUTHOR]

In the current paper, size‐dependent mechanical analysis of functionally graded porous (FGP) nanobeams resting on Pasternak foundation in thermal environment is presented based on nonlocal strain gradient theory and Gurtin‐Murdoch surface elasticity theory. The nanobeam is modeled based on Euler‐Bernoulli beam theory, Timoshenko beam theory and Reddy's third‐order shear deformation theory and the set of the governing equations are solved for a clamped‐clamped FGP nanobeam using generalized differential quadrature method. Numerical results show that as porosity parameter increases, static deflection increases and critical buckling load decreases, but its effect on the fundamental frequency strongly depends on the porosity distribution pattern. It was revealed that among all studied porosity distribution patterns, the minimum value of the static deflection and maximum values of critical buckling load and fundamental frequency can be achieved using symmetric distribution pattern of pores. It is concluded that tensional residual stress reduces static deflection and increases both critical buckling load and fundamental frequency and temperature rise has reverse effects. [ABSTRACT FROM AUTHOR]

Laminated rubber bearings are the key components of base isolated structures. It is important to effectively monitor the axial pressure and shear deformation in rubber bearings. In previous studies, the axial pressure and shear deformation of rubber bearings have been monitored separately using wavelet‐packet‐based method. However, when the axial pressure and deformation of rubber bearings change at the same time, the prediction error of the above method is large. Therefore, this paper proposed a new deep neural network architecture, named P&D‐NET to monitor the axial pressure and shear deformation simultaneously. The P&D‐NET combines wavelet packet decomposition method and fully connected neural network. In this study, the coupling effects of axial pressure and shear deformation monitoring are studied by full‐scale experiments. The details of P&D‐NET are also introduced. Three full‐scale smart rubber bearings (SRB) were tested under different axial pressure and shear deformation to form a real measured dataset. The influence of feature extraction methods, network structures, and weighting coefficient in loss function was investigated to optimize the network. By using the optimal hyperparameters, the root‐mean‐square error (RMSE) of axial pressure prediction and shear deformation prediction in the test set is 1.41 MPa and 17.6%, which has reduced the error by up to 68.8% compared to the previous wavelet‐packet‐based method. [ABSTRACT FROM AUTHOR]

This paper presents a novel higher‐order shear deformation beam theory for analyzing the stability and free vibration of functionally graded (FG) sandwich beams with emphasis on the effect of higher‐order moment (HOM) and cross‐sectional warping. The governing equation of axially loaded FG sandwich beams is derived from three‐dimensional equations of the theory of elastic waves in bodies with homogeneous initial stresses. The characteristic equations for typical end conditions are obtained exactly. The numerical results of the natural frequencies and critical loads are calculated and verified for special cases by comparing them with the existing solutions. The effects of gradient index, core thickness, HOM, and warping shapes on the natural frequencies and critical buckling loads are elucidated for different slenderness ratios and end constraints. [ABSTRACT FROM AUTHOR]

Based on the Mindlin first‐order shear deformation theory, this paper proposes an equivalent single layer (ESL) plate theory to analyze the electro‐mechanical coupling problem of laminated piezoelectric plates (LPPs). The main features of the proposed approach are: (i) It assumes that the electric potential across the thickness is a polynomial function, ensuring its continuity at the interface. (ii) The electric displacements are continuous at the interface, in line with the interface continuity condition between laminated plates. The theoretical solutions for the deformation and electric potential of LPPs are obtained. The validity and accuracy of the theoretical solutions are confirmed through comparison with results of two‐ and four‐layer LPPs obtained from the three‐dimensional finite element method (FEM). The numerical results discuss the influence of different series expansions and emphasize the necessity of high‐order expansion. Meanwhile, the range of application of three‐dimensional FEM is discussed. It is expected that such a new analytical method can be instructive to the optimal design of piezoelectric device. [ABSTRACT FROM AUTHOR]

In this paper, the dynamic performance of Multi‐layered Sandwich Composite Cylindrical Open Shells (MSCCOS) with double‐layered soft cores is analyzed for the first time by adopting the First‐order Shear Deformation Theory (FSDT). For accomplishing this aim, vibration differential equations of MSCCOS are derived based on Hamilton's variance principle. Then, the closed‐form Navier solution is introduced to obtain the numerical results of differential equations. Subsequently, the effectiveness and accuracy are discussed by several comparisons. Ultimately, the dramatic effect of different structural and material parameters on natural frequencies and associated loss factors is investigated and described vividly. Because shear deformation and rotary inertia of all layers are considered in vibration differential equations, thin and moderately thick MSCCOS could be researched, and some interesting discoveries for the dynamic performance of MSCCOS are derived. Highlights: A vibration model of five‐layered composite open shell was obtained.The optimal structure parameters maximizing the damping properties are shown.Dynamics properties of five‐layered composite open shell are presented. [ABSTRACT FROM AUTHOR]

Analogous electrical networks were previously derived from the Euler–Bernoulli and Kirchhoff–Love theories to represent beams and plates, respectively, for use in multimodal structural vibration damping. However, these networks do not account for shear deformations or rotary inertia, which can result in suboptimal vibration damping performance when used on moderately thick beams and plates. In this paper, we investigate the incorporation of shear deformation and rotary inertia using Timoshenko–Ehrenfest beam theory and Mindlin–Reissner plate theory to develop improved electrical networks that can more accurately represent thick beams and plates. Our findings suggest that the inclusion of shear deformation and rotary inertia can significantly improve the frequency coherence of the electrical networks and multimodal vibration damping for thicker structures. The electrical analogs presented here are of use for various applications, especially to conveniently design complex circuit topologies in fields spanning from vibration attenuation to energy harvesting. [ABSTRACT FROM AUTHOR]

This paper studies the multi‐physical fields in a torsional composite fiber composed of a non‐piezoelectric semiconductor (PS) core coated with a piezoelectric dielectric shell. Based on the three‐dimensional framework of piezoelectricity and drift‐diffusion theory, we develop a nonlinear one‐dimensional model that incorporates the warping deformation, shear deformation, and axial variations of the electric field and charge transportations. A One‐dimensional model is linearized for small perturbations of charges, and we obtain the analytical solutions for single rods or PN junctions when torques are applied, which explicitly illustrates the electromechanical fields and redistribution of mobile charges. We also examine how the thickness of the composite rods affects the interaction between the piezoelectric and semiconductor components in the model. The optimal thickness ratio for maximizing the overall mobility of carriers has been discovered. This enables us to modify the thickness ratio to achieve the greatest PS interaction performance. Based on the nonlinear equations, we analyze the relationships between electric currents and applied voltages on the end of rods. Finally, we examine how twisting moments influence the characteristics of this I‐V relationship. The presented study provides a potential application for mechanical switches or sensors for PSs. [ABSTRACT FROM AUTHOR]

One of the key damage observations in modern reinforced concrete (RC) frame buildings, damaged following the 2010/2011 Canterbury and 2016 Kaikoura earthquakes, was localised cracking at the beam‐column interface of capacity‐designed beams. The localised cracking in the beams was due to curtailed longitudinal bars at the beam‐column interface. Following these observations, without experimental data to justify desirable seismic performance, modern beams controlled by localised cracking were assumed to be potentially earthquake‐vulnerable. To address this, an experimental program was carried out on six RC beam specimens susceptible to single‐crack plastic hinge behaviour due to curtailed longitudinal bars. The experimental data show that RC beams with single‐crack plastic hinge behaviour can undergo significant inelastic drift demands without loss of lateral resistance. However, contrary to conventional beams with distributed cracking, the response of RC beams with single‐crack plastic hinge behaviour due to curtailed longitudinal bars is mainly dominated by hinge rotation (via bond‐slip) and shear sliding at the column face. The current paper studies the interdependence of axial elongation, bond‐slip and shear sliding deformation of RC beams with single‐crack plastic hinge behaviour under cyclic demands. A procedure for seismic assessment of RC beams with single‐crack plastic hinge behaviour due to curtailed longitudinal bars is proposed. The proposed formulations can be adopted to develop adequate numerical models for simulating the response of RC frames with beams susceptible to single‐crack plastic hinge behaviour due to curtailed longitudinal bars. [ABSTRACT FROM AUTHOR]

A 10‐story reinforced‐concrete (RC) building was subjected to a shaking table test using E‐Defense, the largest three‐dimensional earthquake simulator in the world, to estimate the effects of a flexible foundation and seismic response of a mid‐rise building. Two structural systems with different base supporting conditions were adopted for two phases of tests for comparative purposes: the first system was free‐standing with base sliding and uplifting, and the second was a conventional RC seismic resisting system with a fixed base. This paper mainly reports the test results for the conventional RC seismic resisting system with a fixed base, which comprises a moment‐resisting frame system in the longitudinal direction and a frame system with multistory shear walls in the transverse direction. The objective of this research was to confirm the seismic capacity of a mid‐rise building designed in accordance with current Japanese building standards and guidelines. Even though the story drift ratio exceeded 3% under extreme motion exceeding the design earthquake, the structure remained stable throughout the tests, satisfying the design concept of collapse prevention performance, whereas relatively severe damage was observed in the beam–column joints. Crack observations indicated massive damage sustained by the beam–column joints. The measured shear deformations at the beam–column joints accounted for more than half of the inter‐story drift at the peak response. [ABSTRACT FROM AUTHOR]

In the present paper, the governing equations of a vibratory beam with moderately large deflection and arbitrary cross‐section are derived by using the first‐order shear deformation theory. The beam is homogenous, isotropic and it is subjected to the axial loads. The kinematic of the problem is according to the von‐Kármán strain‐displacement relations and the Hooke law is used as the constitutive equations. The partial differential governing equations describing the axial and transverse vibrations of homogeneous beams contain four coupled nonlinear equations with variable coefficients which are derived employing Hamilton's principle. The Galerkin method in conjunction with the perturbation technique is applied to obtain the linear natural frequencies. A parametric study is performed and the effects of different thickness functions such as linear, polynomial and trigonometric on the results are investigated. The non‐linear frequencies which contain the corrections on the linear frequencies are calculated. The corrected parts of the non‐linear frequencies are functions of the axial as well as the transverse amplitudes of the vibrations. The influences of the axial load and aspect ratio on the linear and non‐linear frequencies are studied too. To confirm the reliability of the vibration analysis carried out in the present paper, the analytical results are checked with the corresponding numerical results obtained from the finite element analysis. The numerical and analytical results are in a good agreement. [ABSTRACT FROM AUTHOR]

This paper presents a two‐dimensional corotational curved beam element for the dynamic analysis of curved viscoelastic beams with large deformations and rotations. In contrast with traditional straight beam elements, the novelty of the presented formulation lies in introducing a curved reference configuration, which follows the rotation and translation of a corotational frame, to measure the pure elastic deformation of the beam and describe the spatial position of an arbitrary material point. A curvilinear coordinate system is fixed on this reference configuration to measure the local deformation of the element. Based on Hamilton's principle, the global elastic force vector, the global internal damping force vector, the global inertia force vector, and the global external damping force vector are derived using the same shape functions to ensure the consistency and independence of the element. An accurate two‐node curved element and the Kelvin–Voigt model are introduced to consider the axial deformation, bending deformation, shear deformation, rotary inertia, and viscoelasticity of the beam. Three examples are given to verify the validity, computational accuracy, and computational efficiency of the presented formulation. Moreover, the effects of the internal damping and external damping on the dynamic response of a rotating curved beam are investigated. [ABSTRACT FROM AUTHOR]

In this paper, the double‐side direct shear experiments on the specimens with and without grooves were conducted to measure the shear load‐deformation curves of steel fiber‐reinforced concrete containing recycled coarse aggregate (SFRCA). The evaluation method for shear toughness was proposed first, and then the effects of water–cement ratio, replacement ratio of recycled coarse aggregate, volume content of steel fibers, and shear section height on the shear toughness of SFRCA were experimentally analyzed. The results showed that the proposed shear toughness evaluation method could reflect the shear toughness of SFRCA. The effects of the replacement ratio of recycled coarse aggregate and the volume content of steel fiber on the shear toughness of specimens with grooves had the same trend as those of specimens without grooves. The shear toughness ratio of SFRCA increased with the increase of the volume content of steel fibers, and decreased with the increase of water cement ratio and the replacement ratio of recycled coarse aggregate, respectively. Moreover, the residual shear toughness ratio increased almost linearly with increasing water–cement ratio, replacement ratio of recycled coarse aggregate, and volume content of steel fibers, and decreased with the increase of shear deformation, respectively. Finally, the formula for calculating the residual shear toughness ratio of SFRCAC was proposed by fitting the test results. [ABSTRACT FROM AUTHOR]

The strength and deformation of full‐scale adhesively bonded multi‐material joints is studied in this paper. Four joints with a thick layer of methyl methacrylate adhesive (MMA) have been manufactured in shipyard conditions. In two specimens, cracks have been introduced at steel–adhesive and composite–adhesive interfaces. One cracked and one un‐cracked specimen were subjected to quasi‐static tensile testing; the two remaining specimens were stepwise loaded/unloaded with increasing load until failure. The strain in the adhesive layers was measured with digital image correlation (DIC). This showed a predominant shear deformation and dissimilar shear strain patterns for different bond lines. Fibre Bragg (FBG) sensors were used to monitor strains at steel and composite constituents and to detect the onset and evolution of damage in the un‐cracked specimen. Strains measured by FBG sensors correspond well with DIC results at nearby regions. All specimens failed by delamination of the composite panel near the composite–adhesive interface. [ABSTRACT FROM AUTHOR]

During earth pressure balance (EPB) shield tunnelling, a three‐dimensional stress redistribution occurs, which leads to development of soil arching. In this paper, development of soil arching by stress redistribution in two types of soils, silty and sandy soil is studied. A three‐dimensional numerical model was first developed and validated using the case study of the extension of Dwaraka Najafgarh Metro Corridor of Phase‐III of Delhi MRTS. Using the validated model numerous simplified numerical analyses were carried out to determine the evolution of soil arching in both silty and sandy soil. The variation in stresses (σxx, σyy and σzz), deformation and shear strain were evaluated and, on this basis, the extent of the loosened region and soil arching region was determined for both soil types. Furthermore, impact of different parameters (i.e., face pressure, grout pressure, C/D ratio and diameter of tunnel) on the evolution of loosened region above tunnel crown was assessed. Based on the numerical analysis, the extent of loosened region in the vertical direction for silty soil was determined to be 1.21D from the tunnel crown and the extent for the sandy soil was determined to be only 0.73D. While in the horizontal direction, the loosened region extends up to 0.72D and 0.37D for silty and sandy soils respectively. An optimal range of different parameters which must be adopted at the time EPB shield tunnelling in silty and sandy soil is recommended. [ABSTRACT FROM AUTHOR]

In this paper, the shear behavior of glass fiber reinforced polymer (GFRP) bars reinforced ultra‐high‐performance concrete (UHPC) beams was investigated through experimental tests. Eight GFRP bars reinforced UHPC I‐beams were tested until shear failure with various stirrup ratio, reinforcement ratio, and shear span to depth ratio. The shear capacity, load–deflection relationship, cracking pattern, and failure mode were investigated in detail. The results show that the shear span to depth ratio has the greatest influence on the shear capacity of the beam among the three parameters, followed by the stirrup ratio and reinforcement ratio. The stirrup configuration can significantly improve the shear capacity and deformation resistance of the beam and can effectively reduce the stress concentration caused by the uneven distribution of steel fibers, which affects the failure mode of the beam. Increasing the stirrup ratio and reinforcement rate can improve the stiffness of the beam after cracking, and the larger the shear span to depth ratio is, the more significant the improvement effect is. Moreover, the stirrup enables the full development of the tensile capacity of GFRP bars. The existing equations of shear strength from five design codes and seven literatures are compared to the experimental results of 54 UHPC beams. It showed that the formula from the codes AFGC‐2013 and JSCE‐2006 codes is more accurate. The equations by Kwak, Jin, and Thiemicke's provide the best predictions. [ABSTRACT FROM AUTHOR]

This paper describes the simulation technique developed to predict the fatigue life of bolted shear connector. As existing composite structures experience complex loading conditions over the entire life of the structure, therefore, the fatigue behaviour of the shear connectors is always critical. Among different types of bolted shear connectors, the installation procedure of the blind bolts is less complex and more rapid than that of conventional systems. Therefore, the concept of fatigue analysis of the blind bolt shear connector has been presented, in this paper here in, under constant amplitudes cyclic loading, using ABAQUS/explicit and FE‐SAFE programs. All fatigue simulations were conducted under load‐control mode based on constant amplitude conditions and a constant mean force. The results showed that the number of cycles to failure decreases with the increasing stress level while every stress amplitude has a certain number of cycles until failure. [ABSTRACT FROM AUTHOR]

The nonlinear vibration and dynamic responses of functionally graded graphene‐reinforced composite (FG‐GRC) laminated cylindrical, parabolic, and sinusoid panels stiffened by FG‐GRC stiffeners in the uniformly distributed temperature variation are presented in this paper. An improved smeared stiffener technique is used to model the added stiffnesses of stiffeners to the total stiffnesses of panels. The higher‐order shear deformation shell theory (HSDT) with the geometrical nonlinearities of von Kármán is applied to establish the governing formulations. The stress function form is estimated using the approximated technique for complex curvature panels. Lagrange function and Euler‐Lagrange equations are applied, and the Rayleigh dissipation function is taken into account to obtain the nonlinear equation of motion. Numerical examples are investigated using the Runge‐Kutta method to obtain the dynamic responses of panels, and the critical dynamic buckling loads of panels are considered using the Budiansky‐Roth criterion. Some significant remarks on the nonlinear vibration and dynamic buckling responses of three types of stiffened panels can be recognized from the numerical examples. [ABSTRACT FROM AUTHOR]

This paper presented the formulation of a novel hypoplastic model for sand considering both the cyclic mobility and large accumulative shear deformation in the post‐liquefaction stage. Based on experimental observations and existing modeling response, two constitutive ingredients were incorporated into the hypoplastic model to improve its prediction accuracy. First, the fabric change effect was considered, enabling a satisfactory simulation of effective stress reduction under undrained cyclic loading. The second component was the introduction of the semifluidized state concept to reflect the modulus degradation and deviatoric strain development of sand at low‐stress state. The capability of the proposed model is demonstrated by the comparisons between the model responses and experimental results of the cyclic behavior of sand under different test conditions. Remarkably, the liquefaction phenomenon and increasing deviatoric strain amplitude during the post‐liquefaction stage were reproduced well by the model. [ABSTRACT FROM AUTHOR]

This paper proposed a new analytical approach for the nonlinear buckling behavior of axially compressed functionally graded graphene reinforcement composite laminated (FG‐GRCL) stiffened cylindrical panels with the piezoelectric layers resting on the Pasternak's elastic foundation in the uniformly distributed temperature change. A design for the reinforcement of stiffened cylindrical panels is applied where the polymer matrixes of panels and stiffeners are reinforced by graphene sheets. The effects of FG‐GRCL stiffeners are modeled using the improved smeared stiffener technique, which is developed by applying the anisotropic higher‐order shear deformation beam theories for curved and straight stiffeners. The fundamental formulations are obtained by applying Reddy's higher‐order shear deformation theory (HSDT), and taking into account the von Kármán geometrical nonlinearities. The algebraically nonlinear equilibrium equations are achieved by employing Galerkin's procedure, and then they can be solved by using the ordinary calculation process. Some important remarks on the nonlinear buckling of stiffened FG‐GRCL cylindrical panels are archived from the numerical investigation process. [ABSTRACT FROM AUTHOR]

In this paper, N, Nb composite doped lithium iron phosphate structure was constructed, and its thermodynamic stability, intercalation voltages, volume change rate, electronic structure properties, and mechanical properties were systematically investigated using the first principles. The results of formation energy demonstrate that the N and Nb composite doping system meets the thermodynamic stability requirements and can exist consistently. In the process of de‐lithium, the volume change rate of the anion‐cation hybrid doping system is significantly decreased, and the intercalation voltage is increased, which indicates that the doping makes the cycling performance and energy density of the material improved. A radical shift in the material's electronic structure after doping is conducive to the enhanced conductivity of lithium iron phosphate. Besides, studies on the elastic properties of materials demonstrated that both N and Nb doping inhibited the generation of microcracks and diminished the occurrence of shear deformation. [ABSTRACT FROM AUTHOR]

Graphene is a highly conductive and exceptional material that has shown potential for significantly improving the piezoelectric and mechanical properties of piezoelectric matrix. This paper examines the stability of composite plates surface bonded with graphene‐reinforced composite piezoelectric (GRCP) actuators. However, the significant differences in material characteristics at the interfaces will pose some challenges in analyzing the buckling behavior of piezoelectric composite plates by means of existing higher‐order shear deformation theories. To address this issue, a refined plate theory is developed for the buckling analysis of piezoelectric composite plates. The developed theory includes a new interlaminar shear stress field that precisely describes the distribution of interlaminar shear stresses, which differs from earlier higher‐order theories. It should be emphasized that the finite element formulation can be simplified by removing the second‐order derivatives of in‐plane displacement parameters from interlaminar shear stresses. In terms of the developed theory, a four‐node C0 quadrilateral plate element is introduced to examine the buckling behavior of piezoelectric composite plates. Furthermore, the modified interlaminar shear stress field is absorbed into the strain energy, significantly improving the ability to predict the critical loads of composite plates with GRCP actuators. The refined plate model is evaluated through the utilization of three‐dimensional (3D) elasticity solutions and results obtained from other associated theories. Numerical results demonstrate that the refined plate model is capable of producing favorable results, and a comprehensive examination is conducted to analyze the effects of significant parameters on the buckling behaviors of piezoelectric composite plates. This study sets a solid foundation for future research and development on the application of graphene‐reinforced composite piezoelectric actuators in composite structures. Highlights: Buckling analysis of composite plates with GRCP actuators is conducted.A refined plate theory with modified interlaminar shear stresses is developed.The ability to predict critical loads can be significantly improved.The finite element formulation can be simplified based on the proposed model.Comprehensive parametric studies on buckling behavior are caried out. [ABSTRACT FROM AUTHOR]

Reinforced concrete deep beams in bridges and other critical infrastructure are subjected to millions of load cycles during their service life. At the same time, they typically work with high shear and develop critical diagonal cracks. The cyclic loading across the cracks results in fatigue damage of the shear‐resisting mechanisms, which needs to be taken into account in the assessment of existing structures, and in particular in members with small amount of shear reinforcement built according to early design codes. To aid the development of advanced assessment approaches for such structures, this paper presents five large‐scale fatigue tests of deep beams with a stirrup ratio of 0.134%. The beams are preloaded to develop complete diagonal cracks, and then are subjected to cycles with different minimum and maximum load. The focus is placed on detailed crack measurements, needed for the development of crack‐based assessment approaches. The crack data is analyzed with the help of the two‐parameter kinematic theory to quantify important deformations. It is shown that the fatigue across the shear cracks is associated mainly with degradation of aggregate interlock and progressive damage in the critical loading zones. It is also shown that as the maximum load is decreased, the fatigue life increases, and the failure mode can switch from shear to flexure. [ABSTRACT FROM AUTHOR]

This paper presents and analyzes the nonlinear buckling responses of three types of shallow imperfect panels (cylindrical panel, parabolic panel, and half‐sinusoid panel) made from functionally graded graphene reinforced composite (FG‐GRC) on nonlinear elastic foundations subjected to axial compressive load in thermal environments. The nonlinear governing equations are formulated on Reddy's higher‐order shear deformation shell theory (HSDST) and take into account von Karman‐type nonlinearity. A new approximation technique to determine the stress function in average sense is developed and Galerkin's method is used to obtain the algebraically nonlinear equation system. Then, the simple calculation process can be used to solve the obtained equation systems, and the formulations to calculate the critical buckling loads and postbuckling load‐deflection curves are expressed in explicit form. The results can be flexibly applied to FG‐GRC panels with different curvatures in engineering designs. The effects of panel types, geometrical parameters, temperature increase, initial imperfection, and nonlinear elastic foundations on the critical buckling loads and postbuckling curves of cylindrical, parabolic, and half‐sinusoid FG‐GRC panels are discussed in numerical results. Numerical results also show a small disadvantage in the load‐carrying capacity of cylindrical panels compared to parabolic panels and half‐sinusoid shallow panels. Highlights: Postbuckling of cylindrical, parabolic, and half‐sinusoid panels are studied.The panels are made of functionally graded graphene reinforced composite.Reddy's higher‐order shear deformation shell theory is applied.A new approximation technique to determine the stress function is developed.Critical buckling loads and postbuckling expressions are explicitly obtained. [ABSTRACT FROM AUTHOR]

During a shear process the vibrational mode structure of a non‐crystalline model material will change under load. Thus, we expect an effect on the characteristic boson peak, which correlates with numerous features of disordered materials. In this paper, we perform shear deformation on two‐dimensional random network materials and investigate the distribution of their vibrational density of states (VDOS). Furthermore, the spectra of eigenvalues are studied in detail using similar approaches to investigate the eigenvectors and specifically their change due to load and plastic rearrangements. [ABSTRACT FROM AUTHOR]

This paper presents a test case to help validate simulation codes for contact problems involving beams. A closed form solution is derived and the comparison is made with a finite element (FE) implementation that uses the mortar method for enforcing the contact constraints. The test case consists of a semi‐infinite cantilever beam subjected to a constant distributed load and experiencing frictionless contact with a straight rigid substrate. Both an Euler‐Bernoulli and a Timoshenko beam model are considered and the influence of the differing kinematic hypotheses is analyzed. In the case of the Euler‐Bernoulli beam the distributed contact force is equal to the load along the contact region except at the boundary where a point load appears. On the contrary, the rigid substrate exerts a fully distributed load on the Timoshenko beam which decays exponentially from the first contact point and tends towards the applied load. The rate of decay depends on the relative shear deformability. Moreover, whereas in the first case the transverse shear force is discontinuous, it becomes continuous when allowing for shear deformation. An example of benchmarking is given for a particular FE code. The error with respect to the exact solution can be computed and it is shown that the numerical solution converges to the analytic solution when the FE mesh is refined. [ABSTRACT FROM AUTHOR]

Multi‐directional forging technology, as a representative severe plastic deformation technology, is urgent to be developed because it has strong microstructure refinement and performance improvement effects. In this paper, multi‐directional forging experiments of TA15 titanium alloy with different passes were carried out at 700 °C using unrestricted multi‐directional forging die structure. Then the samples of TA15 titanium alloy after multi‐directional forging deformation were subjected to a high‐temperature vacuum annealing treatment. The test results reveal TA15 alloy was effectively refined through multi‐directional forging without any cracking with the increasing of deformation passes. The mechanism of grain refinement during multi‐directional forging included dynamic recrystallization, grain crushing and adiabatic shear deformation bands refinement. The amount and grain size of recrystallization grains increased when the annealing time increased from 1 hour to 4 hours. Supplemented by annealing, the adiabatic shear deformation bands microstructure with the mixed microstructure of coarse αp and fine αs were obtained and the hardness after multi‐directional forging and annealing was investigated. The yield strength and ultimate tensile strength increased by 26.1 % and 25.5 % respectively when the deformation pass increased to 3 passes compared with the initial specimen. The present work revealed that multi‐directional forging deformation combined with appropriate annealing could represent an efficient route to improve the microstructure and mechanical property of TA15 alloy. [ABSTRACT FROM AUTHOR]

This paper presents a new theory for the shear capacity of reinforced concrete members without shear reinforcement. While recognizing that there are multiple failure mechanisms, the theory attributes the opening of a critical flexural shear crack as the lower bound of the shear capacity. It proposes that the shear displacement of an existing flexural crack can be used as the criterion for the unstable opening of the critical flexural shear crack. Based on the theory, the paper presents a simplified shear evaluation model. Compared with the current shear provisions in the design codes, the model is characterized by good accuracy and a solid physical background. It demonstrates a great flexibility for dealing with complex design conditions. As an example, the paper discusses the possibility of extending the theory to the shear resistance of higher-strength concrete. The suggested method provides a more logical and fluent transition from normal- to high-strength concrete and shows good agreement with experimental observations. [ABSTRACT FROM AUTHOR]

Passive materials in human skeletal muscle tissues play an important role in force output of skeletal muscles. This paper introduces a multiscale modeling framework to investigate how age‐associated variations on microscale passive muscle components, including microstructural geometry (e.g., connective tissue thickness) and material properties (e.g., anisotropy), influence the force output and deformations of the continuum skeletal muscle. We first define a representative volume element (RVE) for the microstructure of muscle and determine the homogenized macroscale mechanical properties of the RVE from the separate mechanical properties of the individual components of the RVE, including muscle fibers and connective tissue with its associated collagen fibers. The homogenized properties of the RVE are then used to define the elements of the continuum muscle model to evaluate the force output and deformations of the whole muscle. Conversely, the regional deformations of the continuum model are fed back to the RVE model to determine the responses of the individual microscale components. Simulations of muscle isometric contractions at a range of muscle lengths are performed to investigate the effects of muscle architectural changes (e.g., pennation angles) due to aging on force output and muscle deformation. The correlations between the pennation angle, the shear deformation in the microscale connective tissue (an indicator for the lateral force transmission), the angle difference between the fiber direction and principal strain direction and the resulting shear deformation at the continuum scale, as well as the force output of the skeletal muscle are also discussed. [ABSTRACT FROM AUTHOR]

Traditional coupling beams, once seismically damaged, are very difficult to be repaired. Recent studies developed new coupling beams by introducing mid‐span dampers. The shear deformation is concentrated in the damper, thus protecting the primary concrete members. However, the concentrated shear deformation will result in slab damage. This paper proposes a novel bending‐type steel truss coupling beam (BFTCB) that adapts to slab bending deformation. The steel truss is securely connected to the slab at the top chord. It remains elastic during an earthquake, while inelastic deformation is confined to friction dampers equipped on both ends of the bottom chord. Friction dampers render the coupling beam damage‐reparability, which can be rapidly repaired by retightening or replacing the bolts after a major earthquake. The main body of wall piers sustain negligible damage and can remain in service; thus, they can be exposed to more earthquakes during the lifetime of the building. Unlike solid web sections, the truss configuration decouples bending and shear demands, as well as stiffness and strength, which improves the design flexibility. Quasi‐static tests were conducted to validate the design concepts and confirm the replaceability of the BFTCB. The BFTCB displayed full and stable hysteretic behavior. The theoretical formula for the strength and stiffness of the BFTCB afforded acceptable accuracy. The proposed BFTCB shows promising potential for resilience‐oriented high‐performance structures. [ABSTRACT FROM AUTHOR]

In 2019, the third and updated edition of the Clinical Practice Guideline (CPG) on Prevention and Treatment of Pressure Ulcers/Injuries has been published. In addition to this most up‐to‐date evidence‐based guidance for clinicians, related topics such as pressure ulcers (PUs)/pressure injuries (PIs) aetiology, classification, and future research needs were considered by the teams of experts. To elaborate on these topics, this is the third paper of a series of the CPG articles, which summarises the latest understanding of the aetiology of PUs/PIs with a special focus on the effects of soft tissue deformation. Sustained deformations of soft tissues cause initial cell death and tissue damage that ultimately may result in the formation of PUs/PIs. High tissue deformations result in cell damage on a microscopic level within just a few minutes, although it may take hours of sustained loading for the damage to become clinically visible. Superficial skin damage seems to be primarily caused by excessive shear strain/stress exposures, deeper PUs/PIs predominantly result from high pressures in combination with shear at the surface over bony prominences, or under stiff medical devices. Therefore, primary PU/PI prevention should aim for minimising deformations by either reducing the peak strain/stress values in tissues or decreasing the exposure time. [ABSTRACT FROM AUTHOR]

This paper presents the newly established ACI‐DAfStb database of shear tests on slender prestressed concrete beams without stirrups subjected to point loads. From the 574 collected tests 214 tests remain for the comparison with shear design approaches after the control and selection procedures were applied. The main features of these tests are described. Subsequently, these tests are used to perform evaluations of the shear design procedures of EC2, fib Model Code 2010, and ACI 318‐14. [ABSTRACT FROM AUTHOR]

The dynamic stability response of a micro sandwich beam with leptadenia pyrotechnica rheological elastomer (LPRE) core is studied. The top and bottom layers respectively are assumed as piezoelectric reinforced with carbon nanotubes (CNTs) and porous functionally graded materials (FGM). The core and top layers are affected by magnetic and electric fields for the magnetic and piezoelectric characteristics of the layers, respectively. The Halpin‐Tsai micromechanics theory for obtaining the effective material properties of the nanocomposite layer is utilized. On the basis of Kelvin‐Voigt model, the structural damping of the smart micro beam is assumed. The microstructure is located on the viscoelastic model which is simulated using Visco‐Pasternak platform. The size effects are assumed according to the theory of strain gradient including three‐length scale constants. The various theories of first‐order shear deformation beam theory (FSDBT), third‐order shear deformation beam theory (TSDBT), parabolic shear deformation beam theory (PSDBT), and exponential shear deformation beam theory (ESDBT) are utilized for driving the governing equations according to the Hamilton's principle. The motion final relations are solved by the differential quadrature method (DQM) for presenting the dynamic buckling area. The effects of different components such as volume percentage and distribution of GPLs, porosities, magnetic field of LPRE, applied voltage, FG index, structural damping, and geometric components of the micro sandwich beam on the dynamic stability reign (DIR) of the system are shown. The results with other researcher papers are compared. The results show that the DIR increases by applying a magnetic field to the LPRE layer. [ABSTRACT FROM AUTHOR]

In this paper, the nonlinear bending of functionally graded carbon nanotube‐reinforced composite (FG‐CNTRC) shell exposed to thermomechanical loading is perused. It is assumed that the composite shell is reinforced in the longitudinal axis and is also made from a polymeric matrix. Mechanical features of the constituents are obtained based on the modified rule of mixture, and they are considered to be temperature dependent (TD). Using the first‐order shear deformation shell theory (FSDT) as well as von Kármán type of geometrical nonlinearity, the equilibrium mathematical relations are derived. Utilizing the dynamic relaxation (DR) procedure combined with the central finite difference method, these mathematical relations are solved in diverse boundary conditions. Finally, roles of carbon nanotube (CNT) distributions, boundary conditions, shell radius, thickness‐to‐radius ratios, volume fraction of CNTs, mechanical loads, thermal gradient, and temperature dependency are examined on the results. From the numerical results, it can be inferred that in the shell with the CC boundary condition, the FG‐O distribution of nanotubes has the maximum deflection, and the lowest deflection belongs to the uniform distribution. However, in the SS boundary condition, the highest and lowest values of deflections are related to V and uniform distributions, respectively. [ABSTRACT FROM AUTHOR]

This paper presents an experimental and numerical study of block shear strength of staggered bolted connections made of high strength steel (HSS). The study aims to examine the effect of low ductility and low tensile‐to‐yield strength ratio of HSS material on the behaviour and block shear strength of staggered bolted connections. Two Q690 HSS staggered bolted connections were tested and failed in block shear failure, which was characterised by tension fracture of the staggered net tension plane and significant shear deformation along the shear plane. The test observations were further interpreted by finite element (FE) analysis. The test results and FE analysis indicate that the block shear failure mechanism of staggered bolted connections is the fracture of the staggered net tension plane combined with the yielding of the effective shear plane. Finally, the design methods in various design codes for evaluating the block shear strength of bolted connections were assessed and the results showed that the existing design methods provided inconsistent predictions of the block shear strength of HSS staggered bolted connections. More experimental and numerical works are currently in progress to further understand the block shear strength of HSS staggered bolted connections. [ABSTRACT FROM AUTHOR]

In United States design specifications, shear lag in longitudinally welded connections is accounted for by means of a tabulated factor, which until 2010 was only applicable to plate‐type members having equal length welds on each side, subject to the further constraint of having a minimum weld length equal to the distance between the welds. This created the paradox that connections with longitudinal welds shorter than the distance between the welds were considered by the Specification to have no capacity at all. Research in extant literature based on historical experimental data developed alternative factors that augmented and replaced the previous approaches, making them applicable to longitudinally welded plates, angles, channels, tees, and wide‐flange shapes having equal or unequal weld lengths, and without any weld length‐to‐connection width limitation. This paper presents the results of an experimental study of shear lag effects in longitudinally welded tension members under both in‐plane and out‐of‐plane eccentricity. Forty specimens were tested representing twenty configurations and the experimental results were compared to three theoretical values – (a) the shear lag factor from the 2016 American Institute of Steel Construction (AISC) Specification, (b) the shear lag factor based on a bi‐planar model found in literature, and (c) the shear lag factor from the 2010 AISC Specification. It is concluded that the shear lag factor provided in the 2016 AISC Specification offers the best prediction of the capacity of longitudinally loaded welded connections subject to both in‐plane and out‐of‐plane eccentricity. [ABSTRACT FROM AUTHOR]

Summary: Reinforced concrete (RC) dual systems are composed of RC moment‐resisting frames (MRFs) and RC shear walls, where MRFs are barely designed to handle gravity loads. Investigations have demonstrated that shear walls exert negative effects on the upper part of MRFs. In this paper, the interaction of shear walls and MRFs is inspected using endurance time (ET) method. ET is a dynamic time history‐based pushover procedure in which structures are exposed to a set of predefined intensifying ET acceleration functions. In this method, seismic performance of the considered structure is assessed based on earthquake return periods; during which, required predefined seismic performance objectives are fulfilled. In this study, several buildings with RC dual systems were designed based on the conventional codes. Next, their nonlinear duplicates were generated for the application of the ET analysis. It was revealed that shear wall elements impose considerable rotational demands—exceeding the criteria established by ASCE41‐13—on the beams and columns, especially those located on the upper parts of the buildings. This paper puts forth and reviews certain methods to cushion the negative effects brought about by RC shear walls, along with a detailed discussion on their merits and demerits. [ABSTRACT FROM AUTHOR]

Summary: Displacement‐based seismic assessment of buildings containing unreinforced masonry (URM) walls requires as input, among others, estimates of the in‐plane drift capacity at the considered limit states. Current codes assess the drift capacity of URM walls by means of empirical models with most codes relating the drift capacity to the failure mode and wall slenderness. Comparisons with experimental results show that such relationships result in large scatter and usually do not provide satisfactory predictions. The objective of this paper is to determine trends in drift capacities of modern URM walls from 61 experimental tests and to investigate whether analytical models could lead to more reliable estimates of the displacement capacity than the currently used empirical models. A recently developed analytical model for the prediction of the ultimate drift capacity for both shear and flexure controlled URM walls is introduced and simplified into an equation that is suitable for code implementation. The approach follows the idea of plastic hinge models for reinforced concrete or steel structures. It explicitly considers the influence of crushing due to flexural or shear failure in URM walls and takes into account the effect of kinematic and static boundary conditions on the drift capacity. Finally, the performance of the analytical model is benchmarked against the test data and other empirical formulations. It shows that it yields significantly better estimates than empirical models in current codes. The paper concludes with an investigation of the sensitivity of the ultimate drift capacity to the wall geometry, static, and kinematic boundary conditions. [ABSTRACT FROM AUTHOR]