Seismic hazards, such as bridge pounding, unseating, collapse, etc., cause significant economic losses and affect traffic and safety. Research on seismic measures, such as limiting and unseating prevention devices for the bridge, can effectively prevent damage to the bearings, such as excessive displacement, the pounding of the beam end, etc., in an earthquake. In this paper, the dynamic time-history analysis method was used to study the mechanical behaviors of the bridge structure, such as its seismic performance, structural displacement, pier bending moment, etc. We found that different combinations of seismic measures can effectively reduce the displacement at the bridge expansion joint and bearings. The joint application of an expansion device, restrainer, and unseating prevention devices shows the best limiting effect on bridge displacement and expansion joint displacement. The maximum reduction of bridge expansion joint displacement reaches 48% and is within the allowable deformation range of an expansion device in a large earthquake, and the maximum reduction of bearing displacement reaches 34%, which only slightly exceeds the shear deformation of the bearing. The expansion device, restrainer, and unseating prevention devices have smaller internal forces in this case than other cases, without damage. In contrast to the previous studies on single seismic measures of unseating restrainers, this study investigates the combination of multiple seismic measures and earthquakes of various magnitude. It reveals the catastrophe process of the bridge structure and the cooperation law of seismic measures in an earthquake.

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A nonlinear 3D solid model of hybrid coupled wall system with steel boundary elements has been founded by using FEM software ABAQUS to study its hysteretic behavior under cyclic loading, which considering the geometric large deformation and materials nonlinearity. To verify the efficiency of the model, two specimens with various coupling ratios of 30% and 45% are analyzed, and the results of analysis are compared with test ones. As the bearing capacities of both agree well in different loading stages, so the FEM model has enough accuracy and could be used to study the seismic behavior of hybrid coupled wall system with steel boundary elements. In addition, the results show that this new system dissipates energy by shear deformation of steel beams along and plastic hinge deformation at the bottom of wall, so it has better seismic performance.

The water level in refrigerator must be controlled accurately in order to adjust the refrigerator’s temperature, namely, a flow sensor needs to be designed to measure the water flow into the flume precisely according to the hydro-valve’s structure. In this paper, the simulation analysis has been done using the software FLUENT on the basis of theoretical analysis of the sensor, and the optimization design of the flow sensor structure has been given according to the analysis results, the results show that the flow characteristics of the sensor has been improved.

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