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Based on the weak seismic performance and low ductility of coupled shear walls, engineered cementitious composites (ECC) is utilized to strengthen it to solve the deformation problem in tall buildings more effectively and study its mechanical properties more deeply.

The properties of reinforced concrete coupled shear wall (RCCSW) and reinforced ECC coupled shear wall (RECSW) have been studied by numerical simulation, which is in good agreement with the experimental results. The reliability of the finite element model is verified. On this basis, a detailed parameter study is carried out, including the strength and reinforcement ratio of longitudinal rebar, the placement height of ECC in the wall limb and the position of ECC connecting beams. The study indexes include failure mode and the skeleton curve.

The results suggest that the bearing capacity of RECSW is significantly affected by the ratio of longitudinal rebar. When the ratio of longitudinal rebar increases from 0.47% to 3.35%, the bearing capacity of RECSW increases from 250 kN to 303 kN, an increase of 21%. The strength of longitudinal rebar has little influence on the bearing capacity of RECSW. When the strength of the longitudinal rebar increases, the bearing capacity of RECSW increases little. The failure mode of RECSW can be improved by lowering the casting height of the ECC beam in a certain range.

In this paper, ECC is used to strengthen the coupled shear wall, and the accuracy of the finite element model is verified from the failure mode and skeleton curve. On this basis, the casting height of the ECC casting wall limb, the strength and reinforcement ratio of longitudinal rebar and the position of the ECC beam are studied in detail.

The long-span continuous rigid-frame bridges are commonly constructed by the section-by-section symmetrical balance suspension casting method. The deflection of these bridges is increasing over time. Wet joints are a typical construction feature of continuous rigid-frame bridges and will affect their integrity. To investigate the sensitivity of shear surface quality on the mechanical properties of long-span prestressed continuous rigid-frame bridges, a large serviced bridge is selected for analysis.

Its shear surface is examined and classified using the damage measuring method, and four levels are determined statistically based on the core sample integrity, cracking length and cracking depth. Based on the shear-friction theory of the shear surface, a 3D solid element-based finite element model of the selected bridge is established, taking into account factors such as damage location, damage number and damage of the shear surface. The simulated results on the stress distribution of the local segment, the shear surface opening and the beam deflection are extracted and analyzed.

The findings indicate that the main factors affecting the ultimate shear stress and shear strength of the shear surface are size, shear reinforcements, normal stress and friction performance of the shear surface. The connection strength of a single or a few shear surfaces decreases but with little effect on the local stress. Cracking and opening mainly occur at the 1/4 span. Compared with the rigid “Tie” connection, the mid-span deflection of the main span increases by 25.03% and the relative deflection of the section near the shear surface increases by 99.89%. However, when there are penetrating cracks and openings in the shear surface at the 1/2 span, compared with the 1/4 span position, the mid-span deflection of the main span and the relative deflection of the cross-section increase by 4.50%. The deflection of the main span increases with the failure of the shear surface.

These conclusions can guide the analysis of deflection development in long-span prestressed continuous rigid-frame bridges.

Bending and shear rigidities of woven fabrics depend on fibre, yarn and fabric-related parameters. However, there is lack of research efforts to understand how bending and shear rigidities change in woven fabrics having similar areal density. The purpose of this paper is to investigate the change in bending and shear rigidities in plain woven fabrics having similar areal density.

A total of 18 fabrics were woven (9 each for 100 per cent cotton and 100 per cent polyester) keeping the areal density same. Yarns of 20, 30 and 40 Ne were used in warp and weft wise directions and fabric sett was adjusted to attain the desired areal density.

When warp yarns become finer, keeping weft yarns same, bending rigidity remains unchanged but shear rigidity increases in warp wise direction. When weft yarns are made finer, keeping the warp yarns same, both the bending and shear rigidities of fabric increase in warp wise direction. Similar results for fabric bending and shear rigidities were obtained in transpose direction. There is a strong association between fabric shear rigidity and number of interlacement points per unit area of fabric even when fabric areal density is same.

Very limited research has been reported on the low-stress mechanical properties of woven fabrics having similar areal density. A novel attempt has been made in this research work to investigate the bending and shear rigidities of woven fabrics having similar areal density. Besides, it has been shown that it is possible to design a set of woven fabrics having similar bending rigidity but different shear rigidity.

The hydro-viscous drive (HVD) has been widely used in fan transmission in vehicles, fans, and scraper conveyors for step-less speed regulating and soft starting. It is an efficient method to save energy and reduce consumption. This study aims to analyze the influencing factors of oil film shear torque accurately.

The shear torque calculation model of double arc oil groove friction pairs was established. The influence of groove structure parameters on shear torque was analyzed. The interaction between viscosity temperature and shear torque was considered. Meanwhile, the equivalent radius was calculated when the rupture of oil film appeared. Finally, the test rig of torque characteristics was set up. The variance of shear torque with the input rotation speed under different oil film thickness, different oil temperature, and different flow rate was seen.

The results show that the shear torque increases with the growth of rotation speed. However, the increase of torque is quite gradual because of the effect of the change of viscosity, which is caused by the rise of temperature. The shear torque increases with the decrease of thickness, the increase of inlet flow rate, and the decrease of inlet oil temperature. Meanwhile, when the feeding flow rate is less than the theoretical, the oil film gets ruptured and the shear torque decreases sharply.

The influence on shear torque during full film shear stage in HVD can be achieved much more accurately through both experimental research and theoretical modeling in which groove parameters, influence of temperature, and oil film rupture are considered. Therefore, the shear torque of HVD can be predicted by theoretical model and experimental research in full film shear stage.

The purpose of this paper is to evaluate the mechanical properties of nano‐silver paste sintered lap shear structures and to discuss the effects of loading rate and ambient temperature on shear strength and fracture mechanism.

Single lap shear joints with an area of 2 mm² and thickness of 50 μm were fabricated by joining two copper substrates with nano‐silver paste. The lap shear tests were carried out under strain control mode on a micro uniaxial fatigue testing system with four loading rates and temperatures. The fracture sections were analyzed by SEM observation to determine the effect of temperature on the fracture mechanism.

Results from the study highlighted that the shear strain rate and temperature can have a significant impact on the shear behaviour of nano‐silver paste sintered lap shear joints. The shear strength increased with shear strain rate, but decreased with increasing ambient temperature. The lap shear joints displayed excellent ductility at higher temperatures due to the grain plastic flow.

So far, the investigation of the mechanical behaviour of low‐temperature sintered nano‐silver paste was restricted to a film form. No work had been done on nano‐silver paste connected structures. The findings presented in this paper give a basic understanding of the mechanical properties of nano‐silver sintered joints when sheared under different loading rates and temperatures.

This paper introduces a simple computational model for the analysis on the solder ball shear testing conditions. Both two‐dimensional (2‐D) and three‐dimensional (3‐D) finite element models are used to investigate the effect of shear ram speed on the solder ball shear strength of plastic ball grid array (PBGA) packages. An effective thickness is identified for the 2‐D finite element analysis. By using this effective thickness as a scale factor, it is shown that the 2D model is feasible for the study of 3‐D problems. The computational model is validated by experimental data in terms of load‐displacement curves. The results from both testing and modeling indicate that the shear ram speed has a substantial effect on the solder ball shear strength. In general, faster ram speed can result in higher ball shear strength. Therefore, the characterization of solder ball shear strength is loading rate‐dependent.

To develop a fairly different EHL inlet zone analysis for investigating the contact‐lubricant interfacial limiting shear stress effect on line contact EHL film thickness in isothermal conditions. This analysis is purposed to give fast and qualitatively correct results.

A Grubin‐like EHL inlet zone analysis is derived with closed form of the analytical results of the EHL film thickness, the EHL film pressure, the contact‐lubricant interfacial shear stress and the contact‐lubricant interfacial slipping velocity in the EHL inlet zone based on the assumption of the contact‐lubricant interfacial limiting shear stress in the EHL inlet zone. In this analysis, the lubricant is allowed to slip at the contact surface; The inlet contact surface shape is known from results referenced in this paper; The physical condition for the presence of the film slippage is incorporated; The lubricated area is divided into different kinds of film slippage zones where are, respectively, applied different governing equations. Three deterministic equations in this analysis are obtained and solving these coupled equations gives the solutions of the boundaries of the slip zone and the percentage reduction of the central film thickness by the contact‐lubricant interfacial limiting shear stress effect in this EHL.

Compared with the earlier approaches to the present problem, the present analysis has the advantage of giving fast and qualitatively correct solutions. The results obtained from the present analysis show that the contact‐lubricant interfacial limiting shear stress effect on EHL film thickness is usually strong when the contact‐lubricant interfacial limiting shear stress in the EHL inlet zone is low; This effect can greatly reduce the global EHL film thickness especially in severe operating conditions.

A very useful material for the academic researcher and the engineer who are engaged in the study and measurement of the effect of the contact‐lubricant interfacial limiting shear stress on EHL film thickness and EHL film pressure.

A fairly different EHL inlet zone analysis is originally developed based on the assumption of the contact‐lubricant interfacial limiting shear stress in the EHL inlet zone. The physical condition for the contact‐lubricant interfacial slippage is first incorporated in this analysis. Deterministic governing equations in this analysis are derived and solving these coupled equations gives the final solutions of the present problem. This analysis has the advantage of giving fast and qualitatively correct solutions. It convincible shows the contact‐lubricant interfacial limiting shear stress effect on EHL film thickness and EHL film pressure in the present EHL.

A Molecular Dynamics approach has been used to compute the shear force resulting from the shearing of disks. Two‐dimensional mono‐disperse disks have been put in an horizontal and rectangular shearing cell with periodic boundary conditions on right and left hand sides. The shear is applied by pulling the cover of the cell either at a constant rate or by pulling a spring, linked to the cover, with a constant force. Depending on the rate of shearing and on the elasticity of the whole set‐up, we showed that the measured shear force signal is either irregular in time, regular in time but not in shape, or regular in shape.

A composite triangular equilibrium element for modelling thin plate behaviour is investigated when shear deformation, according to Reissner's theory, is included in addition to bending deformation. The element flexibility matrix is formed as the sum of two component matrices containing the contributions from piecewise linear moment fields and piecewise constant shear fields separately. Properties of the shear component matrix, including its rank, are determined, and the influence of load basis on the pattern of this matrix is studied. The way these properties affect the condition of a flexibility matrix is investigated when the element size/thickness ratio varies, and particularly when this ratio tends towards zero. Load bases are suggested which could avoid certain problems of ill‐conditioning. Condition parameters are evaluated for an equilateral element. Finally, the application of kinematic boundary conditions to the equilibrium is considered.

Deformation studies on eutectic Sn‐Ag solder (Sn‐3.5Ag in wt percent) joints were carried out at a range of temperatures using a rheometric solids analyzer (RSA‐III). Various performance parameters were evaluated with this equipment by subjecting geometrically realistic solder joints to shear loading at various temperatures (25, 75, 100, 125, and 150°C) with a nominal joint thickness of ∼100 μm and 1×1 mm solder joint area. Mechanical properties such as shear stress versus simple shear‐strain relationships, peak shear stress as a function of rate of simple shear‐strain and testing temperature, and creep parameters were evaluated to gain a better understanding of the parameters contributing to thermomechanical fatigue.