The excitations are applied in the longitudinal direction of the bridge span.
In particular, the CFD-computed Cp values were analysed with consideration of the wind directions, number of spans, and greenhouse design factors, such as the roof slope and roof curvature radius.
Based on the analysed results, the CFD-computed Cp values of multi-span greenhouses were suggested for use in structural and cladding designs based on the defined sections of the greenhouse surface, various wind directions, number of spans and design factors.
In addition to the wind direction and inflow turbulence, it was found that the inhomogeneity of the wind field along the span-wise direction of the bridge is also a critical factor that affects VIVs of full-scale bridge.
Layups can also feature parallel layers, however, usually with grain in direction of the main span direction.
Figure 11 shows a typical example of extracted natural frequencies and corresponding amplitudes from displacement in lateral (Y B ) direction of the middle span.
In this case, the time series in lateral (Y B ) direction of the middle span were filtered using the eight-order Type 1 Chebyshev high-pass digital filter with pass-band 0.05 Hz and stop-band 1.1 Hz, which is shown in Fig. 11a-e, show the local frequencies series extracted using a very narrow pass band filter around the dominant frequencies in Table 2.
thick, 2.4 m (8 ft) long in the longitudinal direction of the bridge, and sufficiently wide to span between the girders in the bridge transverse direction.
All circular cylinders had a length of 17.8D and were mounted normal to the direction of the flow, spanning the channel cross-section 0.5 m downstream of the ignition point.
Among the many acquisition geometries satisfying this condition, a simple one is when the direction of projection n spans all directions in a plane, i.e., n = cos α.n1 + sin α.n2 with 0 ≤ α ≤ π and where n1 and n2 are orthogonal unit vectors.
For the test condition, the surround motion was 100% coherent in one of the 36 directions of motion spanning the whole 360°.
