Behavior Of Slabs Research Articles

Fatigue behavior and failure mechanism of steel-concrete composite deck slabs with perforated ribs

This paper aims at investigating the variable-amplitude fatigue behavior and failure mechanism of the steel-concrete composite (SCC) deck slab with perforated ribs. Firstly, two identical full-scale specimens were tested under different fatigue loading procedures. Test results reveal that the fatigue failure process starts with the initiation of cracks at the welding part between the steel plate and perforated rib, after which the slab could sustain tens or hundreds of thousands of load cycles until the crushing of concrete. As load amplitude increases by 54%, the crack propagation rate is accelerated by 300%, and the fatigue life from the crack initiation to the crushing of concrete is reduced by 79%. Higher load amplitude applied in the earlier service stage leads to the irreversible and a higher level of degradation on the stiffness, deformation recovery, and composite action. Further, the finite element (FE) model is established and verified, through which the stress state of the welding part is analyzed. It reveals that owing to the shear transfer between the steel members and concrete layer, the welding part is in the multiaxial stress condition where longitudinal normal stress, vertical normal stress, and shear stress coexist. Subsequently, the crack initiation position is predicted using the critical plane approach based on the SWT parameter, which shows good consistency with experimental results. Finally, by conducting the parametric analysis, the effects of geometric parameters and shear-span ratio on the SWT parameter of the welding part are clarified.

Experimental studies and theoretical analysis of the residual properties of three-span small-scale continuous concrete slabs after a fire

This study investigated the effect of travelling fire scenarios, span–thickness ratios, and recurring ages on the post-fire residual behaviour of small-scale continuous reinforced concrete slabs. The mechanical performance of five fire-damaged continuous slabs and one reference slab were investigated, including load–deflection curves, concrete and reinforcement strains, cracking patterns, and failure modes, and the observations were compared with those discussed in companion papers. In addition to considering the boundary restraint and failure criteria, this study proposed a simple ellipse equation to determine the tensile membrane action region and residual ultimate loads of concrete slabs at the limit state. The results indicated that the travelling fire scenario, including the fire direction and time delay, had a slight effect on the residual behaviour of fire-damaged slabs with larger span–thickness ratios. For fire-damaged slabs with larger span–thickness ratios, flexural failure easily occurred with sufficient development of the tensile membrane action. The proposed ellipse method can be used to accurately determine the residual ultimate loads of fire-damaged continuous slabs with large span–thickness ratios.

Behavior of strengthened concrete slab under eccentric compressive load

PurposeThe purpose of this study is experimental research of the mechanical behavior of slab reinforced by cork composite patch submitted to an eccentric progressive compressive load applied to on impact rectangle of dimensions 28 × 23 cm2. An analytical model and numerical modeling by finite elements are performed. This study is motivated by the evaluation of the effectiveness of this type of partial reinforcement to improve strength and ductility. The results are given by load-displacement curves, tensile damages cartography and ultimate strength histogram.Design/methodology/approachIn experimental protocol, the following two parameters have been considered: the dimensions of the patch and the eccentricity of the load. The sections of the patches are calculated so that the ratio (XP/YP) patch is proportional to the ratio (LD/lD), with a step of 6 cm longitudinally and 4 cm transversely. Several dimensions patches are considered: (6 × 4) cm2, (12 × 8) cm2 and (18 × 12) cm2. The eccentric punching loading test was performed with an eccentricity of the load (1/3) L’ and (2/3) L’ compared to the center of gravity of the slab. Taking into account the eccentricity of the load in estimating the rupture strength, the equations are developed. Thus, numerical simulations are carried, to extract tensile damages cartography.FindingsThe results show that the rupture begins with the appearance of cracks in the unreinforced area. For an eccentricity of 1/3L’, the best strength/section ratio is obtained for patch (12 × 8) cm2, whereas for an eccentricity de 2/3L’, the patch (6 × 4) cm2 gives a better resistance. The results highlight the influence of the composite on the ultimate load. The force-displacement relations are little modified in the elastic phase. The experimental results have been compared with the theoretical models showing a good correlation.Originality/valueThe strength and ductility are depended on the dimensions of the patch and the eccentricity of the load. The use of a patch to cover the most stressed area, in the event of an eccentric axial load is a very economical solution compared to the total reinforcement. The damage field shows that the evolution of cracks depends on dimensions and the position of the patch. Indeed, the eccentricity of the vertical load induces an additional bending moment that will influence the fracture surface. The rupture load and ultimate displacement increase with the surface of the patch.

Numerical Evaluation of the Opening Effects on the Reinforced Concrete Slab Structural Performance

A finite element method was used in this study to investigate the effects of openings on the resistive behavior of concrete slabs. The presented modeling procedure is used to conduct numerical analyses on the response of reinforced concrete slab subjected to in-plane monotonic loads in X (perpendicular to the beam) and Z (parallel to the beam) directions. Initially, the developed numerical model was calibrated and compared with laboratory results. In building this three-dimensional model, it is attempted to accurately model all nonlinear properties of steel and concrete materials as well as the interactions between them. Then, the behavior of bilaterally concrete slabs under different loads was investigated and used as a reference. Finally, the effect of openings under different loads on the strength of concrete slabs was studied. The results confirm that openings have a great influence on the change of hardness, ductility, initiation and cracking path, and stress distribution under shear and gravitational loading. Moreover, by adding an opening inside the diaphragm, not only did beam and block flooring show more fragile behavior, but also its strength and resistance decreased against lateral load. Given the results of the parametric study of the effect of layout, generally, its place became critical at the state that opening disturbed transmission of shear stresses to the collector beams. By adding the area of the opening and loading in X direction, the concentration of the tensile stresses (equivalent to main maximum stresses) was at the tensile edge as well as at the middle of the flooring around the opening. It is worth noting that an increase in the opening’s area caused the number of tensile stresses to be increased at the middle of the flooring. Meanwhile, the concentration of maximum compressive stresses which is equivalent to the main minimum stresses was at the compressive edge, started at the area of the collectors, and stretched to the edge of the opening. Among different layouts, X-1 and Z-3 states were more critical than other states. Considering openings with different layouts, X-1 and Z-3 have the most stiffness deteriorating and strength in such a way that stiffness deteriorating and strength were 39.93% and 37.89%, respectively, for Z-3 model and 38.68% and 43.33%, respectively, for Z-3 model.

Activation model for various punching shear reinforcement types in flat slabs and column bases optimized for design

Various types of punching shear reinforcement have been developed during the past decades to increase the punching capacity and ductility of slab-column connections. Due to diverse geometries and thus varying anchorage conditions, the effectiveness of these elements contributing to total punching resistance can differ significantly. Generally, the degree of activation of shear reinforcement can be described by contributions of anchorage and of bond. Yet, most of current punching design provisions follow a simplified, empirical approach. Despite its mechanical background, the punching design according to the next generation of Eurocode 2 still does not consider the effect of better anchorage of, for example, double headed studs compared to simple stirrups.In this paper, an extended activation formula for flat slabs as well as column bases is proposed as refinement for the next generation of Eurocode 2. This unifying approach considers different anchorage categories and thus enables more progressive design results. After discussing the background of possible activation scenarios, the effects of bond and anchorage in cracked concrete and the kinematic deformation behavior of slabs subjected to punching are identified as governing constraints. The major focus is on the transformation process from mechanical considerations to a simplified design formula to ensure practical applicability.

Investigating the Strength and Durability Properties of One Way Slabs Incorporating Marble Dust as Cement Replacement Material

To reduce the environmental pollution caused by cement manufacturing and to save both the economy and resources, it is required to use alternative waste materials of pozzolanic nature to partially replace cement in the construction industry. Among different cement replacement materials being used now-a-days, marble dust is the one on which limited research has been done especially on the performance of structural members like RC slabs. In this paper, marble dust has been used in different ratios as partial replacement of cement in concrete mix. RC one-way slabs as well as plain concrete standard samples were cast to determine their mechanical properties i.e. compressive, tensile and flexural strengths, stiffness, first & ultimate load, crack patterns, modulus of elasticity, maximum deflection and durability etc. It was found that by increasing the dosage of marble dust in plain concrete samples, workability was decreased. Compressive and tensile strengths of concrete increased up to 7.5% replacement but decreased on further replacement. The permeability of concrete decreased with the addition of marble dust up to 10% replacement, then it increased. The behavior of one-way slabs showed an increase in the first crack load and ultimate failure capacity. Moreover, decrease in the deflection of slabs was observed with the increasing replacement of cement with marble dust. The resistance of concrete against corrosion of steel reinforcement also increased due to less migration of chloride ions. Ultrasonic Pulse Velocity (UPV) tests showed improved homogeneity and stiffness of concrete structure with the replacement of cement by marble dust.

Study on Flexural Behavior of Bubble Deck Slab Strengthened with FRP

Bubble deck sheets are a technique to remove all the concrete from the center of the floor sheet, thus reducing structural dead weight. Inefficient concrete in the center of the slab replaces the high-density hollow spheres (HDPE). The weight decreases and increases efficiency in the plane. Because the bubble deck slab consumes less material, it reduces greenhouse gas emissions into the atmosphere, enabling us to achieve green construction. The benefits include reduced energy consumption - both in production and transportation - and emissions - from production and transportation, mainly CO2 - as well as material, load, and value reduction. It is also a green technology. Reduce the volume of concrete in the bubble deck technology by substituting locally available spherical bubbles. This implies that the monolithic slab element is used to determine load carrying, deformation (deformation), crack, and failure properties in the plant and is subjected to static gravity loads. The resulting conclusions will be used to define the failure mechanisms, and the benefits of the bubble deck slab will be highlighted.

Efficiency of different BFRP-based strengthening techniques in improving flexural behavior of RC slabs

This study aims to analyze the flexural behavior of one-way reinforced concrete (RC) slabs strengthened with basalt fiber-reinforced polymers (BFRP). A total of six slabs were constructed and subjected to four-point flexural experimental tests. One slab served as the control specimen, and two slabs were strengthened with externally bonded (EB) BFRP sheets and near-surface mounted (NSM) BFRP bars, respectively. The other three slabs were strengthened with a composite reinforced mortar (CRM) layer composed of BFRP grids and polymer cement mortar, of which the BFRP grids for one slab were nonprestressed, and those for the remaining two slabs were prestressed. The experimental results indicated that the types of strengthening techniques including EB, NSM and CRM affected the failure mode of the strengthened slab. In comparison with the EB and NSM techniques, the CRM technique was more efficient in improving the serviceability and ultimate behavior of RC slabs, and it was considerably more economical. Meanwhile, the application of prestress in the CRM technique could further improve the cracking load and flexural stiffness of the strengthened slabs. Additionally, an analytical model was presented to predict the cracking and yield loads of the strengthened slabs, and the predictions showed a good agreement with the experimental results.

A numerical study on flexural behavior of biaxial voided slabs containing steel cages

Several roofing systems have been proposed given their significance in concrete structures, in terms of time and resources. A biaxial voided slab system is introduced to improve the solid slab system's performance by creating voids in the concrete and removing ineffective material. In this study, the bending behavior of voided slabs is investigated numerically. For this purpose, a numerical ABAQUS model is presented and then verified using available experimental results. Then, a parametric study was carried out focusing on the plastic balls and their spacing, steel cages, and the position of plastic balls relative to the slab height. As shown in this paper, the presence of plastic balls improves the flexural capacity, because of steel cages. However, the spacing between plastic balls and their position have not a significant effect on flexural behavior. Finally, the numerical results were compared with the ultimate moment capacities from ACI 318-19, AS 3600-18, EC2 2004, and CSA A23.3-19, and were shown that considering steel cages have better consistencies with numerical results.

Punching shear behaviour of RC flat slabs incorporating recycled coarse aggregates and crumb rubber

This paper presents experimental, analytical and numerical investigations to evaluate the punching shear strength of concrete slabs incorporating a combination of recycled coarse aggregate (RCA) and crumb rubber (CR). Therefore, twelve different concrete mixes were designed with various substitution ratios of RCA and CR as a partial replacement of natural coarse aggregate (NCA) and fine aggregate (FA), respectively. Four substitution ratios of RCA (0%, 25%, 50% and 100%) by NCA and three substitution ratios of CR (0%, 10% and 20%) by FA were considered. Twelve simply supported two-way RC slabs with dimensions of 1000 × 1000 × 100 mm were cast and tested. The experimental programme was divided into two stages. The first and second stages were respectively conducted to evaluate the mechanical properties and the punching shear behaviour of concrete slabs incorporating a combination of RCA and CR. Experimental results show that the combination of RCA and CR negatively affects the mechanical properties of concrete. The substitution ratios of rubber content had a more significant effect on the reduction of the concrete strengths than the RCA content. The punching shear strength, stiffness and toughness of RC slabs incorporating RCA and CR decreased with increasing CR and RCA contents. Based on the experimental results, a combination of 25% RCA and 10% CR is the optimum substitution ratios that can be used on the concrete mixture, as it has a minor effect on the punching shear strength of concrete slab. The predictions of five approaches, namely ACI 318–2014, ECP 203, Euro −2, BS8110 and CSA A23.3, were compared with the experimental results. Finally, nonlinear element analysis (ANSYS) was conducted to verify the experimental results with numerical ones.

Behavior of sinusoidal-corrugated-steel-plate–concrete composite slabs: Experimental investigation and theoretical model development

Composite slabs with trapezoidal steel sheets have been extensively used in composite flooring systems. Sinusoidal steel sheets can be fabricated with relatively thicker steel plates and employed in smooth-curved structures such as buried culverts, thus exhibiting a relatively wider application range than trapezoidal steel sheets. Study has rarely been conducted on composite slabs composed of concrete cover and relatively thick sinusoidal corrugated steel plates. This study focus on the bending behavior and longitudinal shear mechanism of composite slabs with sinusoidal corrugated steel plates. Four-point bending tests were conducted considering different slab thicknesses, shear connector types, and numbers. Partial interaction theory was adopted as the basis for the development of the corrugated-steel-plate–concrete composite slab theoretical model. A computer program named CSPC-SSA (Corrugated-Steel-Plate–Concrete Simply-supported Slab Analysis) was written based on partial interaction theory and finite difference method. The Modified Newton-Bisection algorithm was developed to balance the calculation time and accuracy. It can be concluded that the newly proposed shear connector exhibits similar strength and deformation behavior compared to the conventional shear connector, and that the flexural strength of the corrugated-steel-plate–concrete composite slab was positively correlated with the shear connector number and concrete cover thickness. Improperly increasing the concrete cover thickness may cause longitudinal shear failure.

Increasing occupant localization precision through identification of footstep-contact dynamics

Information regarding occupants inside buildings has the potential to improve security, energy management, and caregiving. Typical sensing approaches for occupant localization rely on mobile devices and cameras. These systems compromise privacy. Occupant localization using floor-vibration measurements, induced by footsteps, is a non-intrusive sensing method that requires few sensors (one per ~35 m2). Current occupant-localization methodologies that rely on vibration measurements are data-driven techniques. These techniques do not account for the structural behavior of floor slabs leading to ambiguous interpretations of vibrations measurement in the presence of obstructions and varying floor rigidities. In this paper, a model-based approach using error-domain model falsification (EDMF) is used to overcome these limitations. EDMF incorporates information related to physics-based models in the interpretation of vibration measurements to identify a population of possible occupant locations. EDMF accommodates systematic errors and model bias to reject models that contradict measurement data. Uncertainties from multiple sources such as modeling imperfection and walking-gait variability are included explicitly while estimating occupant locations using EDMF. A unique approach to identify footstep-contact dynamics is proposed and evaluated for its ability to improve the precision of occupant localization. The approach involves dividing the floor-slab into zones using knowledge of structural behavior. Clustering measured vibrations to define several footstep-contact severity levels helps reduce uncertainty in walking gait thus improving the accuracy of footstep-contact dynamics to use as loading input into model simulations. The utility of occupant localization using this approach is evaluated using a full-scale case study. Localization precision increased by more than 50% compared with non-zone-based strategies.

CONCRETE SLAB REINFORCED WITH GFRP AND EXTERNALY STRENGTH WITH CARBON SHEET UNDER IMPACT LOAD

When FRP bars used in concrete structures that exposed to harsh environments, their service life extended and the cost of their life cycle reduced. Recently, methods of externally bonding Carbon Fiber Reinforced Polymer (CFRP) sheets to RC slabs proposed to improve the dynamic behavior of RC slabs under impact load. In this study, the effect of the number of CFRP sheet layers (one or two) and the arrangement of CFRP sheets (covering the whole or parts of the surface) on the dynamic behavior of slabs reinforced with GFRP bar investigated. Nine specimens of (1550×1550×150) mm reinforced by GFRP bars were tested. A single control specimen was unstrings and eight specimens were strength with CFRP sheet on the tension face. A rigid steel projectile used to apply two dropping-weights of 150 kg as an impact load. The height of the drop was 5 meters. To determine punching shear capacity and critical velocity of perforation, different codes used and compared with the experimental results. The results of the experiments revealed that slab shear properties have a significant impact on their general behavior. Strength slab with carbon sheet enhances the behavior of RC slabs under impact loads and increases shear punching capacity.

NUMERICAL EVALUATION OF SLAB THICKNESS EFFECT ON THE IMPACT BEHAVIOR OF CONCRETE SLABS REINFORCED WITH CFRP BARS

Theoretical investigation of the nonlinear behavior of concrete slabs reinforced with CFRP bars subjected to a single impact load is presented in this paper. For predicting the impact load on a concrete slab, there are several methods, some of which are impractical or prohibitively pricey; however, due to significant technological advancements, simulation methods instead of experimental approaches have become common methods and a cost-effective matter for developing detailed responses. The purpose of this paper is to numerically investigate the effect of slab thickness on the impact response of concrete slabs reinforced with (CFRP) bars when subjected to a single impacting load, so as to well understand their behavior which are considered modern topics and rarely highlighted. Three specimens (1800×1800) mm, with three thicknesses 80, 130 and 180 mm, simply supported by their corners, have been modelled, one reference specimen of 130 mm thickness. The reference slab numerically validated with an experimental work from literature under dropping-weight of 150 kg, it was a flat-nosed rigid steel (300*300*700) mm projectile, used to apply impacting load, which is falling freely from a height of 3.26 m. To assess slab behavior, impact force-time, displacement-time and reaction force-time histories had been plotted and discussed. The analytical results showed that slab thickness is a control factor and better performance in slabs reinforced with CFRP bars, can be achieved by increasing slab stiffness via its thickness increase.

Australian Plate Subduction is Responsible for Northward Motion of the India‐Asia Collision Zone and ∼1,000 km Lateral Migration of the Indian Slab

AbstractDistributions of slabs within Earth's mantle are increasingly used to reconstruct past subduction zones, based on first‐order assumptions that slabs sink vertically after slab break‐off, and thus delineate paleo‐trench locations. Non‐vertical slab motions, which occur prior to break‐off, represent a potentially significant source of error for slab‐based plate reconstructions, but are poorly understood. We constrain lateral migration of the Indian slab and overlying India‐Asia collision zone by comparing tomographically imaged mantle structure with plate‐kinematic constraints. Following coupling of the Indian and Australian plates at the onset of collision, ∼1,000 km lateral migration of the Indian slab was driven by vertical subduction of the Australian slab. The sinking behaviors of individual slabs do not evolve in isolation, but instead influence, or are influenced by, other slabs in the same plate network. Hence, lateral slab migrations may be determined by interpreting the sinking behavior of slabs collectively, and with respect to plate kinematics.

Shear bond behavior of composite slabs with ultra-lightweight cementitious composite

This study investigates the structural behavior and shear bond strength of composite slabs composed of profiled steel deck and ultra-lightweight cementitious composite (ULCC). ULCC topping with a density of about 1440 kg/m3 was used to reduce the dead weight of the composite slabs. An experimental investigation was carried out to determine the shear bond characteristics between the profiled steel sheet and the ULCC. Eight composite slabs of different shear spans were tested in accordance with EN 1994-1-1:2004, in which six slabs contained ULCC and the remaining two slabs contained normal weight concrete (NWC) to serve as a benchmark for comparison. The shear bond behavior of the ULCC composite slabs was compared to that of the NWC slabs using two sets of slabs with short and long shear span lengths. The composite slabs with ULCC topping showed higher ductile behavior and load-carrying capacity than the composite slabs with NWC topping. The shear bond properties of the composite slab with ULCC were determined using the semi-empirical m−k method and the partial shear connection method (PSC) according to EN 1994-1-1:2004. For comparison purposes, the shear bond properties of NWC composite slabs were determined. ULCC was found to provide equivalent shear bond strength with profiled steel sheet compared to the conventional composite slab with NWC. Therefore, ULCC can be used effectively in composite slabs with a greater reduction in self-weight.

Structural behavior of two-way slabs cast with different fiber types and contents

This paper presents an experimental investigation on the effects of incorporating Stainless-Steel Fibers (SSF) on the flexural behavior of reinforced concrete two-way slabs. For this deal, three types of steel fiber (straight, hooked, and corrugated steel fiber) are used. Each type of steel fiber was added in four different volume fractions. Each steel fiber shape was added separately by proportions (0, 0.5, 1, 1.5) % of the total concrete volume. Subsequently, ten 800 × 800 mm × 100 reinforced concrete slabs (three slabs for each type of fibers, one for each proportion, and the remaining one slab was the control) were cast and subjected to flexural tests. The effect of type and amount of SSF on flexural behavior of two-way slabs were studied. That, where 0.5% of steel fibers was added, the straight fibers were acknowledged in comparison to the others whereas the improvement to the stiffness was better and the ultimate load increased by 22.58%. At 1% of steel fibers, the ultimate load increased by (35, 43, and 29) % for straight, hooked, and corrugated fibers respectively which at this addition ratio the hooked fibers were the notable contributor as opposed to other types, and this observation was apparent in improving splitting and flexure strength for hardened concrete. Adding 1.5% of steel fibers to the concrete degrade the workability severely by (83-92)% for all types of steel fibers in parallel with little improvement on slabs behavior is contrary to 1% ratio, thus, the 1% is the recommended addition.

Structural Behavior of High-Strength Concrete Slabs Reinforced with GFRP Bars.

In this manuscript, structural testing was conducted on high-strength concrete slab specimens to investigate the behavior of such specimens when reinforced with a locally produced GFRP reinforcement. Subsequently, a finite element model (FEM) was constructed and validated against the experimental results. In the experimental phase, a total of eleven specimens (nine were reinforced with GFRP, while two were reinforced with conventional steel) were constructed and tested. The slabs dimensions are 700 mm × 1750 mm with variable thickness from 100 mm to 150 mm and different reinforcement ratios using different diameters. The structural behavior of the tested slabs was investigated in terms of ultimate load, ultimate deflection, load–deflection relationship, and crack pattern. Additionally, a nonlinear finite element model using the software ANSYS 2019-R1 was constructed to simulate the structural behavior of slabs reinforced with GFRP bars. The results obtained from the finite element analysis are compared with experimental results. The outcomes showed that the contribution of GFRP rebars in concrete slabs improved slab ductility and exhibited higher deflection when compared with traditional steel rebars. Good agreement between experimental and nonlinear analysis was obtained.

Experimental study on the shrinkage behaviour of steel concrete composite slab

AbstractSteel concrete composite slabs are widely adopted in civil engineering and their numbers are rapidly increasing in Japan. A steel concrete composite slab is connected between concrete and a bottom steel plate by a shear connector. FaB‐Tec Japan Corporation developed a rigid type of shear connecter with a pipe that passes through the long hole on the steel rib. The load‐carrying capacity and durability of this design have been confirmed to be equal to or more than those of the headed stud and perfobond‐rib because the long hole of the steel pipe is filled with concrete. However, the time‐dependent behaviour, especially drying shrinkage, of this type of slab remains unclear. A steel concrete composite slab contains more steel than reinforced and prestressed concrete slabs; the effect of drying shrinkage is therefore expected to be greater owing to the steel restraint. To address this question, drying shrinkage tests were performed on steel concrete composite slabs and reinforced slabs. The change of stress resultants induced on the concrete, reinforcing bar and bottom steel plate was obtained by solving the simultaneous equation derived from the equilibrium conditions for stress resultants and the compatibility condition of strain and curvature.

A comparison between cyclic and monotonic behavior of composite diaphragm interfaces under high shear force

AbstractUsing a novel experimental test setup, the behaviour of composite floor slab interfaces having different deck rib orientation and end anchorage detail has been investigated. In the first floor slab configuration, the deck rib orientation was parallel to the supporting beam. For the second and third floor slab configurations, the deck rib orientation was perpendicular to the supporting beam. In the second floor slab, the steel deck did not continue over the top flange in order to give a solid rib of concrete surrounding the shear studs along the secondary beam. The third floor slab used the standard end anchorage detail adopted in Europe, in which the steel deck continued over the top flange and shear studs were welded to the steel beam through the steel deck. Three nominal identical specimens of each detail were constructed and tested. The first specimen of each detail was tested monotonically and the second and third ones tested cyclically.In the elastic range, the results of reversed cyclic loading were found to be similar to those of the monotonic tests, with the backbone curves being very similar. The ultimate in‐plane shear strength of all three was lower than that of the monotonic tests by around 15%. Under cyclic loading, the envelope response of slippage was similar to the monotonic loading response. Slippage of specimens was found to be insignificant in the elastic range even after the yield point, a very small amount of slippage was observed until the specimen reached the ultimate shear strength. Then the slippage increased relatively significantly and the load dropped, with the rate of load decrease being different between configurations.