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Zr-4 alloys were vacuum brazed using Ag–Cu–Ti filler metal. The effect of brazing temperature on the microstructure evolution, shear strength and corresponding fracture behavior of the brazed joints was investigated. The typical phases at the brazing temperature of 800, 840 and 930^∘C were inferred to be three different microstructures, i.e., a mixture of (Cu, Ti) phases and Ag-rich phase, Ag-rich phase and brittle intermetallic compound (IMC) AgZr, and a uniformly mixed morphology of CuZr and AgZr. And the width of the whole brazed seam increased from 78.4$\mu$m to 118.8$\mu$m. Meanwhile, the shear strength of the brazed joints first increased and then decreased followed by a small increase. The maximum shear strength of 138MPa was obtained at the treatment of 800^∘C for 10min. The fracture morphology exhibited typical brittle fracture characteristics, and the cracks initiated from the interface of the brazed joints, and propagated into the intermediate zones.

The horizontal press performance of column is deteriorated because of its special-shaped section. Moreover, because the antiseismic performance of column is worse, special-shaped column is only used in regions where seismic intensity is lower. So the main problem is to enhance the ductility and shear capacity. This test study on mechanical performance has been carried out through 14 SRCLSSC and 2 RCLSSC. The study focuses on the impacts of test axial load ratio (n_t), hooped reinforcement ratio (ρ_v), shear span ratio (λ) and steel ratio (ρ_ss) on the shear strength and the antiseismic performance of SRCLSSC. It can be concluded that the shear strength of SRCLSSC is increasing with the increasing of n_t and ρ_ss, but the degree of increasing is small when n_t is a certainty value, and that the shear strength of SRCLSSC is decreasing with increasing of λ; The shear resistance formula of L-shaped column is derived through tests, the calculated results are in correspondence with those of the tests. It also can be concluded that the hysteretic loops of the SRCLSSC are full and the hysteretic behaviors are improved; the displacement ductility is increasing with increasing of ρ_v and ρ_ss, but decreasing with the increasing of n_t; the degree of variety in high axial load ratio is larger than that in low axial load ratio. If steel bars are added, the shear strength and displacement ductility of SRCLSSC are increased in a large degree.

Cr coating on Zr-based fuel tubes is a potential approach for the development of accident tolerant fuels (ATF). To settle the cracking behavior and quantitative evaluation of shear strength of Cr coating under different loading conditions, the average shear strength between Cr coating and zircaloy substrate has been estimated using a modified shear-lag model in this paper. Its key parameters are determined experimentally, and the tensile method has been used to research the cracking behavior of Cr coating under different strain rates. The results show that with the increase of strain rate, the interfacial shear strength increases because of the decrease of cracking spacing, while the shear strength changes erratically with the coating thickness increases. Furthermore, abundant two unequal-crack-spacings and few two equal-crack-spacings are observed which are perpendicular to the loading direction.

In this study, Carbon–Carbon (C–C) composite joints were prepared using BNi-1a paste filler metal as the intermediate layer in a vacuum brazing method. The interfacial structures and compositions of the joints were analyzed using scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and X-ray diffraction (XRD). The results show that element interdiffusion and chemical reactions occurred in the joining zone, and various compounds were formed, including Cr₃C₂, Ni₃₁Si₁₂, Ni(_s.s), MB and MC ((M = Cr, Fe, Ni). The optimum joining parameters were determined to be the brazing at the temperature of 1120^∘C for 60 min, which produced the joint with the maximum shear strength of 24.13 MPa. The joint shear strength and fracture morphology demonstrate that bonding temperature and retention time have a significant effect on the strength of C–C composites.

In this paper, high-nitrogen steel (HNS) was joined by vacuum brazing using an Ag–Cu–Ni filler metal and the effect of brazing temperature and duration time on the evolution of mechanical properties and microstructure of HNS joints were analyzed. The results showed that the optimal brazing temperature was 950${}^{\circ }$C and the optimal shear strength was obtained with the value of 212.4 MPa when the brazing temperature was 950${}^{\circ }$C with the brazing time of 10 min.

Ag–26.7Cu–4.5Ti filler metals with different contents of SiC nanowires were prepared to analyze the effect of SiC nanowires on the microstructures, melting temperature, wettability, shear strength and fracture morphology of brazed joints. The results indicate that a small amount of SiC nanowires ($\le$0.1%) can refine the matrix microstructure and reduce the Cu–Ti intermetallic compounds, which can induce the increase of shear strength of brazed joints with 46.7% maximum amplitude, the ductile pattern is the main fracture mode for Ag–Cu–Ti–1.0 SiC brazed joints. Moreover, the SiC nanowires can improve the spreading are of Ag–Cu–Ti filler metals on steel substrate with a 9.4% increase amplitude, when the content of SiC nanowires is more than 0.1%, the wettability can be reduced obviously. The addition of SiC nanowires can show little effect on the melting temperature, which results in the same brazing temperature for Ag–Cu–Ti–$x$SiC filler metals. With the optimization content of SiC nanowires, the optimal content of SiC is 0.05–0.1%, excessive SiC addition with agglomeration can decrease the wettability and shear strength.

Compared without electroless Ni–P alloy coating on the SiCp/Al composites, the paper describes the effect of Ni–P deposited layer on the microstructure evolution, shear strength, airtightness and fracture behavior of vacuum brazed joints. Void free and compact reaction layers along the 6063Al/Ni–P deposited layer/filler metal interfaces indicated that the joints exhibit high airtightness with He-leakage less than $2.0\times 10^{-8}$ $\mathrm{\text{Pa}}\cdot {\mathrm{\text{m}}}^3/\mathrm{\text{s}}$. Energy Dispersive X-ray Spectroscopy (EDS) analysis showed that the reaction layers mainly included brittle Al–Ni and Al–Cu–Ni intermetallics, where fracture occurred in priority and the shear strength was less than 90 MPa. However, without Ni–P alloy coating, sound joints with high shear strength of 100.1 MPa but low airtightness with He-leakage higher than $1.45\times 10^{-7}\mathrm{\text{Pa}}\cdot {\mathrm{\text{m}}}^3/\mathrm{\text{s}}$ were also obtained at 590${}^{\circ }$C for soaking time of 30 min. In this case, a few holes that occurred along the filler metal/SiC particle interface significantly decreased the compactness of the joints. Therefore, according to the requirements in practical applications, suitable choice was provided in this research.

This paper discusses the various joining methods with faying surface modifications used to join AA6063 and AISI304L dissimilar alloys by Rotary Friction Welding (RFW) process at different welding conditions mainly with friction pressure (FP), upset pressure (UP) and friction time (FT). This paper also studies the tensile behavior of the welded joints. The fabricated dissimilar joints were tested using universal testing machine against tensile load, and the mechanical properties of all 30 nos. of weld joints like elongation (%), strength coefficient ($K$), strain hardening exponent ($n$), strain hardening rate (TS/YS ratio), shear strength, etc. were calculated from the tensile testing results and plotted here with a standard error bar. Hollomon’s equation is considered here to study the stress and strain hardening relation and Von Mises yield criterion is considered for shear and yield stress correlation. Total elongation is also calculated from the initial and final length obtained during the tensile test. Since fracture ductility of the joints depends on the stress, strain, ‘$K$’ and ‘$n$’ values, it is important to study these mechanical properties and how the tensile results can be used for their estimation is detailed in this paper. The faying surfaces influence the mechanical properties as well.

Owing to the superior mechanical performance, corrugated steel webs are extensively applied and their shear performance is critical, because of the thin wall. After the steel is corroded and the web is weakened, the problem of shear resistance may become more prominent. The shear performance of corrugated steel webs with local uniform loss was studied to simulate a common corrosion state. Twenty-eight FE models with different defect characteristics, containing defect height and web thickness, are established to simulate corroded corrugated webs. Shear capacity, shear strength, out-of-plane stiffness and bending stiffness are studied. Based on previous studies, the prediction formula is proposed to predict the residual shear strength. Additional FE models are built to validate the reliability. Results indicate that web thickness is the key factor to decide the deformation shape and shear capacity, compared with defect height. Bending stiffness decreases as defect increases. With 62.5% of the initial thickness, the influence of the variation of defect height on the bending stiffness is within 10%. Variation in thickness also affects the sensitivity of shear capacity to corrosion parameters and failure modes. When the thickness exceeds 1.25 mm, about 62.5% of the initial thickness, shear capacity is more sensitive to corrosion height than when the thickness is less than 1.25 mm. The proposed formula is validated and has a good agreement with the FE results, which could help to design the durability of corrugated steel webs and evaluate the performance of existing corrugated steel webs.

The results of some simulated seismic load tests on reinforced concrete one-way interior and exterior beam-column joints with substandard reinforcing details typical of buildings constructed in New Zealand before the 1970s are described. The tests were conducted using both deformed and plain round longitudinal reinforcement. The interior beam-column joint cores lacked transverse reinforcement and the longitudinal bars passing through the joint core were poorly anchored. The exterior beam-column joint units contained very little transverse reinforcement in the members and in the joint core. In one exterior beam-column joint unit the beam bar hooks were not bent into the joint core. That is, the hooks at the ends of the top bars were bent up and the hooks at the ends of the bottom bars were bent down. This anchorage detail was common in many older buildings constructed before the 1970s. In the other exterior beam-column joint unit the hooks at the ends of the bars were bent into the joint core as in current practice. The improvement in performance of the joint with beam bars anchored according to current practice is demonstrated. In addition, tests were conducted on interior joints with lap splices in the beam longitudinal reinforcement bars near the column face. The tests were conducted using both deformed and plain round longitudinal reinforcement. Tests were also conducted on columns with plain round bar longitudinal reinforcement and inadequate transverse reinforcement.

The reinforcing details were close to identical to those in an existing seven storey reinforced concrete building that was designed and built in New Zealand in the late 1950s.

The test results give an indication of the performance of beam-column joints and members with the above now out-of-date reinforcing details.

The test results reported are a summary of results reported in a number of publications written since 1994.

The research work presented in this paper deals with the seismic assessment of hollow bridge piers strengthened with fibre-reinforced polymer (FRP). The scope of the strengthening is to overcome some common deficiencies derived from the use of non-seismic design rules, which can often lead to inadequate response when operating in cyclic loading. The strengthening design was studied by means of a parametric analysis considering different fibres and geometrical parameters applied to typical case studies. Quasi-static cyclic tests were performed on five 1:4 scaled piers designed according to old non-seismic Italian codes and strengthened according to the previous analytical study. Efficiency of FRP strengthening was evaluated by comparing the experimental results with those obtained in a previous experimental research performed on similar non-strengthened specimens. Base shear versus lateral deflection curves, dissipated energy and collapse mechanisms comparison shows the achievable effectiveness once the debonding risk has been overcome.

The paper describes the formulation of a non-linear, two-dimensional beam finite element with bending, shear and axial force interaction for the static and dynamic analysis of reinforced concrete structures. The hysteretic behaviour of "squat" reinforced concrete members, in which the interaction between shear and flexural deformation and capacity is relevant for the overall structural performance, is emphasised. The element is of the distributed inelasticity type; section axial-flexural and shear behaviours are integrated numerically along the element length using a new equilibrium-based approach. At section level a "hybrid" formulation is proposed: the axial-flexural behaviour is obtained using the classic fibre discretisation and the plane sections remaining plane hypothesis, the shear response instead is identified with a non-linear truss model and described with a hysteretic stress-strain relationship. The latter contains a damage parameter, dependent on flexural ductility, that provides interaction between the two deformation mechanisms. The element has been implemented into a general-purpose finite element code, and is particularly suitable for seismic time history analyses of frame structures. Analytical results obtained with the model are compared with recent experimental data.

This paper discusses the effects of electro-deposition processing conditions on the film composition and surface morphology. The rate of Ag deposition onto the bump depends on various processing parameters like current density, agitation and temperature. Among these parameters, the Ag content in the bump was found to be most sesitive to current plating density. At various Ag content, the morphology of the deposited solder was found to be different. This is due to the different types of drain growth at different Ag content. A high content bump was found with a needle-like Ag₃Sn structure. This strcuture is believed to be the cause for the reduction in shear strength.

This paper presents a study on strengthening infill walls using composite materials to enhance shear capacity. The cementitious matrix-grid (CMG) material was employed for this purpose. Various configurations of the CMG, including single or double layers, applied to one or both sides of the wall, with or without anchorage, were tested. The study consisted of two stages. Initially, the mechanical properties of the bricks, mortar, and CMG mortar were determined using twenty-seven specimens. In the second stage, ten specimens, divided into five groups with one group left unstrengthened, underwent shear tests. Shear strength and shear strain relationships were determined for each specimen. Comparative analysis between strengthened and unstrengthened specimens revealed the effectiveness of the strengthening technique. The strengthened specimens exhibited superior structural performance compared to the control specimens. Specifically, the average maximum shear strength of all strengthened specimens surpassed that of the controls. Moreover, double-layer strengthening notably improved ductility. The findings suggest that applying a double layer of CMG to both sides of the wall with anchorage is the most effective method for strengthening. CMG composites significantly enhance the shear strength of infill walls and promote ductile failure. The comparisons of different strengthening combinations can contribute significantly to the existing literature and the construction sector by offering retrofitting options that can be tailored to address various economic and temporal, as well as target strengthening considerations.

This paper deals with the adhesion strength of laminated bamboo composites fabricated only from steam-exploded bamboo plates by using a hot-pressing method. The adhesion strength of laminated bamboo composites were evaluated by a short beam bending teats. The effects of molding conditions on the shear strength were examined by changing the molding temperature, time, and pressure. The optimum molding conditions of the laminated bamboo composites are 140°C, 30 min. and 10 MPa among the conditions investigated. The maximum shear strength of the laminated bamboo composites was approximately 46 MPa, and this value is comparable to that of single plate bamboo composites without lamination.

This paper deals with the shear strength of prestressed concrete box girders having corrugated steel webs (PCBGCSW), with particular emphasis on the shear lag and the stochastic variation of material properties. First, the shear strength curve of corrugated steel web is proposed based on experimental and analytical results obtained for simply supported beams composed of corrugated steel web without and with concrete flanges. In order to evaluate the shear strength of PCBGCSW based on the shear strength curve of corrugated steel web, it is important to know the distribution of shearing force between the corrugated steel web and the concrete flanges. The effect of the concrete flanges, therefore, on the distribution of shearing force is investigated considering the shear lag behavior. Finally the stochastic variation of material properties for the evaluation of the shear strength of corrugated steel webs is discussed from the design viewpoint.

The horizontal press performance of column is deteriorated because of its special-shaped section. Moreover, because the antiseismic performance of column is worse, special-shaped column is only used in regions where seismic intensity is lower. So the main problem is to enhance the ductility and shear capacity. This test study on mechanical performance has been carried out through 14 SRCLSSC and 2 RCLSSC. The study focuses on the impacts of test axial load ratio (n_t), hooped reinforcement ratio (ρ_v), shear span ratio (λ) and steel ratio (ρ_ss) on the shear strength and the antiseismic performance of SRCLSSC. It can be concluded that the shear strength of SRCLSSC is increasing with the increasing of n_t and ρ_ss, but the degree of increasing is small when n_t is a certainty value, and that the shear strength of SRCLSSC is decreasing with increasing of λ; The shear resistance formula of L-shaped column is derived through tests, the calculated results are in correspondence with those of the tests. It also can be concluded that the hysteretic loops of the SRCLSSC are full and the hysteretic behaviors are improved; the displacement ductility is increasing with increasing of ρ_ν and ρ_ss, but decreasing with the increasing of n_t; the degree of variety in high axial load ratio is larger than that in low axial load ratio. If steel bars are added, the shear strength and displacement ductility of SRCLSSC are increased in a large degree.

In this paper, Kalman filter technology which originally came from the field of signal control is introduced as an inverse analysis to identify some important material parameters. By performing detailed FEM simulation and using the experimental data of the force and displacement curve of the fiber pull-out test, the Kalman filter recursive process is successfully carried out to identify the values of the shear strength τ and the fracture energy G for the SiC (SCS-6) / Ti material interface. The great advantage of this inverse technology is that the influence of experimental noise can be taken into account. The calculation results show that the rate of convergence to the correct solution depends on the number and the initial estimation of unknown parameters to be identified and the accuracy of the measured data. Our analysis demonstrates that the proposed approach is suitable and capable in the identification of material parameters of the composite interface.

In order to reduce the brittleness of soil stabilized by lime only, a recent study of a newly proposed mixture of fiber wastes and lime – rice hush ash mixtures for ground improvement is described in this paper. The research was conducted to investigate the influence of the mixture of wastes fibers on the mechanical properties of the stabilized clay soil with lime-rice husk mixtures. The amount of lime and rice husk ash was used 12% by dry weight of soil specimen. The fiber content and length are 0.4% (by weight of the parent soil) and 2 mm respectively. The specimens were subjected to triaxial tests under unconsolidated – undrained condition (UU) condition which is tested after 3, 7, 14 and 21 days of curing. Stress and strain relationship shows the post-peak stress which indicating ductility behavior of the treated soil. It was found that the addition of fibers contributed significantly on the shear strength parameters of the treated soil and the shear strength increased with increasing the curing time.

The shear strength of unsaturated soil is one of the important engineering properties. On the basis of referring to the Chinese and foreign literatures, mainly from the theories and formulas, instruments as well as the specific aspects of the experimental research results to summarize, the paper outlines the advance in research on shear strength of unsaturated soil. Although different scholars have carried out extensive studies and obtained certain research results, also, the view of the difference between shear strength of unsaturated soil and shear strength of saturated soil is the matrix suction's contribution to the strength is approved by academia now. There are still some problems that the scope of shear strength formulas of unsaturated soil, the difficulty of measuring matrix suction and the experimental conditions can't reflect the real stress state of unsaturated soil. Therefore, the further researches are needed to improve the shear strength theory system of unsaturated soil.