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It is well known that stainless steel has many advantages such as superb durability, ductility, and corrosion resistance. Thus, the use of stainless steel for various structural members in construction fields is recently increasing. Structural behaviors of bolted and welded connections, compressive and flexural members, beam-column joints, seismic devices etc. have been conducted experimentally and numerically and thus new design methods have been proposed. Hence, in this study, both experiment and finite element analysis were conducted to assess the block shear failure behaviors of double-shear four-bolted connections made of austenitic stainless steel (STS304) with thinner plate and larger end distance, which are beyond the range of previous literature. The main parameter was end distance and edge distance. Block shear strengths by parametric analysis and test results study were compared with design predictions. It is found that current design equations tended to significantly underestimated test and analysis results. Therefore, modified block shear strength equation was recommended for austenitic stainless steel double shear bolted connection treated in this study.

This paper presents the behaviour and design procedure of bolted connections which tend to be sensitive to block shear failure. The finite element method is employed to examine the block shear failure. The research-oriented finite element method (RFEM) model is validated with the results of experimental tests. The validated model is used to verify the component-based FEM (CBFEM) model, which combines the analysis of internal forces by the finite element method and design of plates, bolts and welds by the component method (CM). The CBFEM model is verified by an analytical solution based on existing formulas. The method is developed for the design of generally loaded complicated joints, where the distribution of internal forces is complex. The resistance of the steel plates is controlled by limiting the plastic strain of plates and the strength of connectors, e.g., welds, bolts and anchor bolts. The design of plates at a post-critical stage is available to allow local buckling of slender plates. The prediction of the initial stiffness and the deformation capacity is included natively. Finally, a sensitivity study is prepared. The studied parameters include gusset plate thickness and pitch distance.

Adhesive bonding is increasingly being used for composite structures, especially in aerospace and automotive industries. One common joint configuration used to test adhesive strength is the single-lap shear joint, which has been widely studied and shown to produce significant normal (peeling) stresses. When bonding composite structures, the normal stresses are capable of causing delamination before the adhesive bond fails, providing inconclusive engineering data regarding the bonding strength. An alternative test is the block shear joint, which uses a shorter sample geometry and a compressive-shear loading to reduce normal stresses. Analytical models proposed by Goland and Reissner and Hart-Smith are used to compare the edge-bending moment for the two joint configurations. The stress distributions along the bondline are also compared using finite element analysis. Experimental tests are conducted to evaluate these analyses and the failure modes of each configuration are recorded. Block shear samples demonstrate a joint strength over 100% higher than single-lap shear specimen bonded with the same adhesive material. The lower joint strength measured in single-lap shear is found to be potentially misleading due to delamination of the composite adherend.

Eight partially grouted (PG-RM) concrete masonry walls were tested to study the influence of the strength and width of blocks, the wall aspect ratio, the horizontal and vertical reinforcement ratio, and the presence of edge elements (flanges). The results were analyzed in terms of the failure mode, damage progression, shear strength, lateral stiffness degradation, equivalent viscous damping ratio, and displacement ductility. Additionally, the performances of some existing shear expressions were analyzed by comparing the measured and predicted lateral load capacity of the tested walls. Based on the results, a slight increment in the lateral stiffness was achieved when employing stronger blocks, while the shear strength remained constant. Besides, increasing the width of concrete blocks did not have a significant effect on the shear strength nor in the initial tangential stiffness, but it generated a softer post-peak strength degradation. Increasing the wall aspect ratio reduced the brittleness of the response and the shear strength. Reducing the amount of vertical reinforcement lowered the resulting shear strength, although it also slowed down the post-peak resistance degradation. Transversal edge elements provided integrity to the wall response, generated softer resistance degradation, and improved the symmetry of the response, but they did not raise the lateral resistance.

This paper presents the details of experimental testing of block masonry triplets using the direct shear test to investigate the shear behaviors of block unit-mortar interfaces. Hollow blocks of 100 and 150 mm (4 and 6 in.) thickness and solid blocks of 100 mm (4 in.) thickness were included in the testing program. These were combined with mortars of three grades to cast a total of 84 triplets. In addition to testing the triplets in an unconfined state, three increasing levels of precompression stresses were used separately to test the confined specimens. The shear behaviors of the tested triplets were not influenced by block strength, while shear strength increased (almost) linearly with mortar strength. The mean peak shear stress for the unconfined triplets was 0.4 MPa (58 psi), whereas the average shear modulus of the joint for these triplets was 6.20 times the mortar compressive strength. The Mode II fracture energy of the masonry joints increased at higher precompression levels. The methods of determining shear strength, shear modulus, and shear strength parameters for the mortar joint in block masonry are proposed using the observed data. Keywords: block masonry triplets; fracture energy; mortar grade; precompression stress; shear modulus; shear strength.

This paper investigates the behavior of PM-type polyurethane flexible joints connecting structural components. Although flexible polyurethanes are known for their energy dissipation capacity and ability to accommodate large deformations—particularly under seismic actions—research addressing their performance under shear loading remains limited. The primary objective of this work was to characterize these joints under varying levels of normal stress, identify failure modes, and estimate key mechanical parameters. Nine masonry triplet specimens, composed of concrete units and PM-type polyurethane, were subjected to shear testing using a procedure adapted from EN 1052-3. Tests were carried out at three precompression levels: 0.2, 0.6, and 1.0 N/mm2. Tensile tests were further performed to calibrate material models. The results showed that increasing precompression led to higher ultimate shear loads. All specimens failed due to shear failure at the unit–flexible joint interface, with no damage observed in the masonry units. Based on linear regression following EN 1052-3, the initial shear strength was determined to be 0.729 N/mm2, corresponding to a friction coefficient of 0.14.

Interface shear transfer is vital to maintain the structural integrity of concrete composite elements. Therefore, shear connectors are provided at the concrete joint interface to maintain such integrity. Due to its high tensile strength and non-corrodible nature, glass fiber-reinforced polymer (GFRP) reinforcement can be used as shear connectors in composite elements, particularly those in harsh environments. Fifteen pushoff specimens were constructed and tested to failure. The specimen consisted of two L-shaped concrete blocks cast at two stages to provide the cold joint interface. The test parameters were the type, shape, and ratio of shear-friction reinforcement and concrete strength. It was demonstrated that GFRP-reinforced concrete (RC) specimens with reinforcement ratios of 0.36% or more could resist the shear-friction stresses similarly to their steel-RC counterparts. Also, increasing the concrete strength increased the shear-friction capacity significantly. Moreover, the design model in the Canadian Highway Bridge Design Code resulted in very conservative predictions. Keywords: cold joint; composite elements; glass fiber-reinforced polymer (GFRP); pushoff; shear connectors; shear friction.

Based on the 3D laser scanning technology, the surface morphologies of the rock blocks collected from the soil–rock mixture (S–RM) were scanned. The numerical model of the S–RM with different rock block proportions were established. To study the deformation and failure characteristics of the S–RM during the formation and evolution of the shear band, the numerical large-scale direct shear tests under different normal stresses were performed on these S–RM samples, the failure points were recorded by the detection of contact failure. Base on the step accumulation of particle’s spin, the rotation angles of rock blocks were monitored in the simulation. A parameter Pθ is introduced to describe the evolution characteristics of the shear band. Results show that the, Pθ of the S–RM with the rock block proportion of 60% is obviously greater than the others. The formation and evolution process of the shear band in the S–RM was consistent with the evolution process of the local particle’s rotation. The rotation of the soils always preceded the rotation of the rock blocks, which reflects the “bully” deformation characteristic of S–RM in the shear band formation process. In the form of the failure distribution, the interior failure of the S–RM with low rock block proportions was mainly the thin band-shaped destruction between the soils. However, higher rock block proportion caused more interactions between soils and rock blocks in the S–RM, and the destruction presented a thick cloud-like distribution. The shear fractures in the soils and tensile fractures along the contact planes between soils and rock blocks are the main failure pattern of S–RM under shear tests.

The mechanical characterization of block-in-matrix rocks (bimrocks) remains a significant challenge in geotechnical engineering, primarily due to the difficulty of obtaining undisturbed specimens. While the Volumetric Block Proportion (VBP) is a recognized controlling factor, the specific role of block orientation is not well quantified. This study employs a systematic experimental approach, augmented by Response Surface Methodology (RSM) and Analysis of Variance (ANOVA), to investigate the effect of block orientation angle relative to loading direction ( α ) on the uniaxial compressive strength (UCS), deformation, and failure mechanisms of bimrock. A total of 87 synthetic specimens with VBP from 0% to 50% and α from 0° to 90° were tested. Statistical analyses confirm that both VBP and α, as well as their interaction, are statistically significant for both UCS and Elastic modulus. An increase in VBP reduces UCS, though this effect reduces with increasing α. Failure analysis reveals that higher VBP increases crack density, while an increase in α from 0˚ to 90˚ forces failure paths to become more tortuous. The Elastic modulus increases with VBP, with the most pronounced stiffening effect at α  = 0° (vertical alignment). This effect diminishes with an increase in α and approaches that of the pure soil for α  = 90°. In contrast, Poisson’s ratio showed no systematic trend, underscoring its sensitivity to local heterogeneity of Bimrock. This research conclusively demonstrates that block orientation is a critical, independent governing parameter. Consequently, predictive models must account for the interaction between block proportion and orientation to accurately simulate bimrock behaviour.

Presently, structural grade cross-laminated timber (CLT) panels are manufactured for interior applications. To expand the use of CLT to exterior applications, there is a need to protect the panels from biodegrading agents such as fungi and termites. Pressure treatments are effective methods of increasing the durability of wood and wood-based products. There are limited studies on the influence of micronized copper azole (MCA) treatment on the rolling shear modulus and rolling shear strength of a commercially produced 3-ply southern yellow pine CLT panel Grade V3. It was found that MCA treatment didn’t have a significant effect on the rolling shear strength of the CLT panels, with the rolling shear strength being 2.19 and 2.31 MPa for the untreated and treated CLT panels, respectively. The bonding durability of the CLT panels had mixed results, with the control specimens measuring a significantly lower wood failure percentage (WFP) of 32% as compared to approximately 75% for the MCA treated specimen. The measured block shear strength (BSS) was approximately the same for the treated and the untreated shear block specimen except for one manufacturing group. The average delamination for the treated specimens was 11% while the average delamination for the untreated specimens was 13.2%.