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The aerodynamic characteristics of the two iced vertical circular cylinders in a tandem arrangement, due to the shape change by icing, are complex, and lack systematical investigation. Therefore, a set of wind tunnel tests were carried out to study the aerodynamic characteristics of the leeward vertical cylinder, with ice shape, icing thickness, cylinder spacing, and icing relative position of cylinders varied in the subcritical Reynolds number range in this study. Results show that the icing thicknesses had a greater impact on the lift coefficients of D-shaped ice leeward cylinder at the same angle of attack. The aerodynamic characteristics of the iced leeward cylinder were stable when the ratio (L/D) of cylinder spacing was within the range of 4.8–6.2. The change of flow field should be considered in the stability analysis of two circular vertical cylinders. The drag coefficients of the iced leeward cylinder varied significantly due to the shielding effects, especially within the range of 9° attack angle and L< 6.2D. The results of this work can provide an experimental reference for future research on wind resistance of two circular cylindrical structures in engineering practice.

Wind-profile simulation is fundamental to structural wind engineering. The transiting test method is used to test the wind-resistance performance of structures via vehicle-driving wind. Herein, we establish a novel method of simulating the wind profile of Commonwealth Advisory Aeronautical Research Council (CAARC) high-rise building standard model type-C-terrain by using flat plates through a transiting test method. Effects of several factors (i.e., the distance between flat plates and Pitot tubes, the length of flat plates along the wind direction, the distance between adjacent flat plates, the number of flat plates, and the vehicle speed) on the simulation results of type-C-terrain wind profiles were investigated. The results confirm the feasibility of applying a transiting test method to simulate wind profiles. The vehicle speed is 72 km/h (20 m/s). When the distance between the flat plates and the Pitot tubes is properly adjusted from 300 mm to 340 mm, the length of the flat plates along the wind direction is 200 or 300 mm. The results well agree with the wind-profile curves corresponding to the type-C-terrain in Chinese Load Code GB 50009-2012. Overall, this study provides a novel method of simulating type-C-terrain wind profiles.

An analytical model is developed to predict residual stresses formed during plasma cladding process. This is based on the force and moment balances and misfit strain caused by differential coefficient of thermal expansion (CTE) of substrate and cladding layers during cooling. The model can be implemented by a simple programming. Residual stresses can be predicted from a knowledge of material properties, temperature of substrate and layers and specimen dimensions. Residual stresses are calculated after each layer rather than as a whole. Specific results can be obtained for the distribution of residual stresses within Co-based layers system. The effect of temperature of substrate and layers, the number of layers, the curvature of a composite beam on the residual stresses are discussed. It has been found that the residual stresses decrease with the increase of preheating temperature of substrate and inter-layer temperature of layers. The curvature increase with increasing layer number.