Wind tunnel tests are a commonly used method for studying wind characteristics of complex terrain; but truncation of the terrain model is usually unavoidable and affects the accuracy of the test results. For this reason, the effects of truncated and original terrain models on the simulation of wind characteristics for complex terrain were investigated by considering both nontruncated and truncated models, with the truncated model considering the applicability of two types of transition sections. The results show that the effect of topographic truncation on profiles of mean velocity and turbulence intensity is different for regions and that inclination angle profiles are extremely sensitive to the changing topographic features upwind. In those cases, the spectra of streamwise velocity were overestimated in the low-frequency range but underestimated in the high-frequency range due to topographic truncation. At the same time, the less negative value of the slope of the spectra was found at the inertial subrange. Furthermore, the normalized bandwidth was also influenced by topographic truncation, which was narrowed in windward and leeward regions and broadened in the valley region. We should note that the performance of the transition sections used in this study was quite limited and even resulted in inaccuracies in the simulation.

Due to the asymmetrical cross section of long-span rail-cum-road twin-girder bridges, the aerodynamic interference effect and flow characteristics of the twin girders in the gap are complicated. To study the influence of spacing on their aerodynamic characteristics, section model wind tunnel tests were conducted on a long-span rail-cum-road twin-girder cable-stayed bridge. This study considered the two conditions of bare and completed girders and the two inflow directions of 0° and 180°, with a spacing ratio range of L/Br = 0.1–2.0, and tested the surface wind pressures of the twin girders. Their aerodynamic and flow characteristics were analyzed, and the influence of spacing on their aerodynamic interference was clarified. The results show that for asymmetrical twin girders, the spacing and direction of incoming flow are still the key factors affecting their wind pressure distribution and flow characteristics. Due to the asymmetry of twin-girder sections, the influence of spacing on the wind pressure distribution and flow pattern varies with different flow directions. Furthermore, the attachments to completed girders enhance the asymmetry, making the aerodynamic and flow characteristics more complex than those of bare girders. Finally, three flow patterns are summarized: the upstream girder lower surface wake acts on the downstream girder fairing lower surface, acts on its fairing upper surface, and acts at its fairing.

In accordance with the metal-composite structure ice impact status, an experiment of Ice Impact on Aluminum/Carbon Fiber Reinforced Composite dual plate was carried out to study the dynamic responses and damage of the target dual plate. The artificial ice ball with a diameter of 35 mm was launched by a 37 mm gas gun test system to impact the metal face of the plate, high-speed photography was used to measure the launching speed of ice balls and record the impact process. The internal damage of composite plate and the displacement of metal part were measured. Experiment results showed the external damage of the composite plate was mainly manifested by the shallow elliptical impact dent formed on the impact surface contacted with the aluminum plate, with the increase of the impact energy level, the damage on the back of the plate became more serious. When the impact energy reached 400 J, the back of the plate was damaged by fiber breakage. The internal damage measurement results showed The internal delamination shape of the [0/90]_4s plate and the [0/45/90/-45]_2s plate were similar to that of the cross-shaped and plum blossom-shaped laminates, respectively, and the delamination failure was mainly caused by interlaminar shear stress due to the different bending stiffness between layers.

The aerodynamic characteristics of twin-separated parallel decks for long-span rail-cum-road bridges with various wind barriers clamped at railway girder are more complicated because of aerodynamic interference. Experimental investigations on aerodynamic coefficient and wind pressure coefficients of twin girders under different incoming flow directions were conducted using wind tunnel tests. Three different heights ( H) varying from 2 m to 4 m and four different ventilation ratios ( R) varying from 20% to 50% for wind barriers were examined. Results indicated that the aerodynamic coefficients were affected significantly by the incoming wind direction, which must be considered, and the railway wind barrier affected the aerodynamic characteristics of the railway girder when it is located both upstream and downstream, but the laws are not the same. Due to the aerodynamic interference effect of the twin parallel girders, the aerodynamic characteristics of the adjacent highway girders were also affected by the wind barrier along the railway girder, especially when the highway girders were located downstream. While, the highway girders were less affected when located upstream. The influence of wind barrier height and ventilation ratios on the adjacent highway girders was completely different. Most importantly, the parameters optimization of wind barriers clamped at railway girders should be determined after a comprehensive evaluation of the aerodynamic characteristic of both the railway and highway girders.

The aerodynamic coefficients transiting test is a new method for measuring the structural aerodynamic coefficients using the wind generated by a moving vehicle. However, the effect and correction of natural wind on the transiting test has not been studied. Hence, in this study, the investigation of the aerodynamic force and pressure measurements on a special triangular prism model is simulated through the transiting test under different natural wind conditions for 30° and 90° angles of wind incidence. Force and pressure measurement results in the transiting test are used to describe and explain the effect of natural wind in the range of 0–3.0 m/s on the aerodynamic coefficients of the symmetric triangular prism qualitatively and quantitatively. The results show that the driving wind field of the vehicle, aerodynamic force coefficient, and aerodynamic pressure coefficient are significantly influenced by strong natural wind greater than 1.71 m/s, which must be considered and so it is recommended that the structure aerodynamic coefficients transiting test should be conducted under the condition that the natural wind is less than 1.71 m/s. In addition, the method of two-direction round-trip measurement is proposed to modify the effect of natural wind on transiting tests.