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Constructing porous wind barriers is one of the most effective approaches to increase the running safety of trains on viaducts in crosswinds. This paper aims to further improve the wind-sheltering performance of the porous wind barriers.

Improved delayed detached eddy simulations based on the k-ω turbulence model were carried out, and the results were validated with wind tunnel tests. The effects of the hole diameter on the flow characteristics and wind-sheltering performance were studied by comparing the wind barriers with the porosity of 21.6% and the hole diameters of 60 mm–360 mm. The flow characteristics above the windward and leeward tracks were analyzed, and the wind-sheltering performance of the wind barriers was assessed using the wind speed reduction coefficients.

The hole diameters affected the jet behind the wind barriers and the recirculation region above the tracks. Below the top of the wind barriers, the time-averaged velocity first decreased and then increased with the increase in the hole diameter. The wind barrier with the hole diameter of 120 mm had the best wind-sheltering performance for the windward track, but such barrier might lead to overprotection on the leeward track. The wind-sheltering performance of the wind barriers with the hole diameters of 240 mm and 360 mm was significantly degraded, especially above the windward track.

The effects of the hole diameters on the wake and wind-sheltering performance of the wind barriers were studied, by which the theoretical basis is provided for a better design of the porous wind barrier.

As an important part of steel bridge deck pavement, if waterproof adhesive layer performance does not meet requirements, numerous kinds of bridge deck pavement distress may be encountered. To study the adhesive behavior of rubber asphalt waterproof adhesive layers in steel bridge gussasphalt pavement, the pull-off and direct-shear tests have been used in the study to mechanically simulate steel bridge deck pavement under vehicles loading.

Several potentially influential factors associated with the adhesive strength of rubber asphalt are investigated including temperature, spraying quantity and environmental conditions.

Results indicate that rubber asphalt was associated with good performance with respect to its use as a waterproof adhesive layer; simulated performance was negatively correlated with increasing temperatures. A necessary spraying quantity of 0.4 Lm^-2 is required for appropriate adhesive strength of the composite structure, with a decrease in adhesive strength noted when spraying quantity is significantly greater or less than this.

The current paper presents an examination of the adhesive performance of a rubber asphalt adhesive layer on steel bridge deck pouring construction, while additionally examining potentially influential factors and conditions via use of both pull-off and shear tests.