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Accurate FEA model of torsion beam suspension and its strain histories are keys to precisely predicting its fatigue life. A strain analysis method is presented, integrating FEA and neural network analysis. The displacement and force histories of the wheel center and strain histories of multiple measurement points on the suspension are measured from road durability test. Apply transient response analysis to determine the FEA model and obtain strain histories of the measurement points. Use a neural network method to obtain accurate additional load. By comparing analysis results and test data, the accurate strain response of torsion beam suspension can be gained

This paper presents the experimental results of recycled aggregate concrete filled steel tube columns prepared with different amount of recycled coarse aggregate (RCA) subjected to axial loading. The recycled coarse aggregates are obtained from the earthquake waste in Sichuan. Based on the studying of the physical and mechanical properties of recycled coarse aggregate, the mechanical property of recycled aggregate concrete (RAC) with five concrete mixes with 0%, 25%, 50%, 75% and 100% RCA respectively are prepared. The behaviour of the circular solid steel tube columns are studied in terms of the load carrying capacity, ductility and strain response under axial compressive loading in addition to the physical and mechanical characteristics of RCA and RAC. The results show that the steel tube column gives lower ultimate bearing capacities when the RCA were added. However, no obvious difference on the failure modes were found between the steel tube columns filled with recycled aggregate concrete and normal concrete.

This paper presents the simulation of gold wire bond shear test. The stress and strain response of the gold ball bond during wire bond shear was examined. The simulation was done using a A 3D non-linear finite element model. The effects of the shear ram height on the stress and strain response of the gold ball bond were investigated. The results of the simulation confirms that shear ram height has a significant effect on the von mises stress and equivalent strain response of the gold ball bond during wire bond shear test.

Based on the test data of shaking table tests of subway station structure in soft ground under both near-field and far-field earthquakes, the spatial effects of peak ground acceleration (PGA) of soft ground as well as peak strain response of the subway station structure are analyzed. The results show that the peak acceleration of measuring points on both major and minor planes increases with the growing peak acceleration of earthquake. The law of PGA and frequency spectral character of measuring points on different observation planes or at different depth varies with each other, and there presents remarkable spatial effect. The peak strain of central cylinders on the major plane appears larger than that on the minor planes. There are sharp contrasts among the peak strain responses in different spatial positions of the station structure.

The internal mechanical response of asphalt pavement structure is difficult to be obtained because of the limitations of theoretical calculation and present testing methods. In order to get practical information of instructure layers, this paper analyzed the cumulative and instantaneous strains of layers’ bottom of semi-rigid base asphalt pavement based on Accelerated Pavement Testing and Fiber Bragg Grating sensors, as well as got the spatial distribution and time-variation law of longitudinal, lateral and vertical strain responses under controlled loading condition. The research result shows that under the moving vehicle loads, there is an obvious alternative property of tension-compression as the strain response of the pavement structure, and different variation shapes of instantaneous stain are in different layers from top to down. Also the measured instantaneous three-direction strain of the bottom of each surface are higher than the calculated values with BISAR, while they anatomizes well in base. This paper can be regarded as useful and tentative research and application on future correlative study.

Based on the failure model of building structural steels under earthquake loading, High strain low cycle fatigue properties of HRB400QST (yield strength grade 400MPa, Quenched and Self Tempered) reinforced steel bars with diameters of 20mm and 16mm(unmachined) and HRB400V-N MA(microalloying)with diameters of 16mm (unmachined) were investigated. Based on the tests of total strain controlling, cycle strain response character of three kinds of steel bars and the relationship between cyclic stress and strain were researched. Hollomon and Coffin-Manson formulas were used to induce fatigue life formulas of three kinds of steel bars, and then the values of σa·Δεt were gained when Nf =100, calculated results show that the high strain low cycle fatigue properties of HRB400V-N MA rebars tested are much better than HRB400QST steel bars. Rupture surface scan reveals that surface hardened layer will reduce the cyclic toughness, and is bad for the anti-seismic performance.

The nonlinear viscoelastic response of a PVC-Coated Fabric has been studied. For the needs of the present study, creep and recovery tests in tension of both the warp and the weft directions at the different stress levels were executed while measurements were made of the creep and recovery strain response of the system. For the description of the viscoelastic behaviour of the material, Schapery’s nonlinear viscoelastic model was used. For the description of the nonlinear viscoelastic response and the determination of the nonlinear parameters, a method by using a combination of analytical formulations and numerical procedures based on a modified version of Schapery’s constitutive relationship where an instantaneous plastic and a transient plastic terms were added, has been developed. The method has been successfully applied to the current tests.