Sectional Model Wind Tunnel Test and Research on the Wind-Induced Vibration Response of a Curved Beam Unilateral Stayed Bridge

Abstract

The linear curve distribution of the beam and the asymmetrical layout of the stay cables may have beneficial or adverse influences on cable-stayed bridges. Sectional model wind tunnel tests and numerical simulations were used to analyze the influence of these two factors on the wind-induced vibration characteristics of a curved beam unilateral stayed bridges (CBUSB) and the interaction between its stay cables and curved beams. According to the basic similarity law, the sectional models of a CBUSB example were designed and manufactured. The aerodynamic force and wind-induced vibration of the models were measured in an atmospheric boundary wind tunnel laboratory to obtain the aerodynamic coefficient and displacement, respectively. Based on the wind tunnel test results, the verified finite element model was used to determine the displacement, acceleration, and cable tension of the CBUSB excited by the buffeting force under 5 curvature cases and 4 cable layout cases. Then, band-pass filter technology and fast Fourier transform technology were used to analyze the influence of these two parameters on the wind-induced vibration characteristics of the CBUSB. Results show that the CBUSB had good aerodynamic stability in the wind tunnel at low and high wind speeds. With increasing curvature, the high-order modal vibration and modal coupling vibration of the CBUSB may be generated. The frequency, the proportion of wind-induced vibration response components, and the distribution characteristics of spectrum energy of CBUSB will be affected by 4 cable layout schemes. Cables arranged on both sides of the bridge and near the center of curvature can improve pedestrian comfort and reduce wind-induced vibration, respectively. Affected by the interaction between cable and bridge, the cable and bridge transmit their own vibration to each other, both of which contain the response components of each other.

Study the Influence of Cable Breakage on Wind-Induced Vibration Characteristics of the Curved Beam Unilateral Stayed Bridge

“…According to the size of the wind tunnel laboratory and the bridge in the case, the geometric scale ratio of the stage model was determined to be 1:100. The main parameters of the sectional model, the produced sectional model, and the wind field characteristics used in this test were detailed in Table 1, Figure 2 and Chapter 3.2 in the paper of Zhao et al [1]. The aerodynamic coefficients were determined by aerostatic force tests, and the cases of test wind attack angle were set to −12 • -12 • and ∆θ = 10, for a total of 25 cases.…”

“…The curvature of the five finite element models adopted in this section is based on the 1 to 5 cases of the CBUSB literature studied by Zhao et al [1]. The finite element models under the 5 cases are shown in Figure 3.…”

“…Curved beam unilateral stayed bridges (CBUSBs) have the advantages of lightweight and beauty and are often used in the construction of pedestrian landscape bridges [1]. The cable breakage of CBUSBs is often accompanied by wind loads, which can change the wind-induced vibration characteristics of such structures.…”

“…The increase in the former suppresses the along-wind wind-induced response but leads to the response spectrum being denser and makes the bridge more likely to generate modally coupled vibration. The cable arrangement on the side near the curvature center benefits in reducing the acceleration peak response [1]. Therefore, when analyzing the CBUSB's wind-induced vibration characteristics under cable breakage action, the influence of the above two key factors is very necessary to be considered.…”

Research on construction monitoring of curvilinear continuous beam bridge jacking and horizontal moving construction

“…Synchronous jacking technology has been rapidly promoted and widely applied as the highway bridge and culvert industry continues to develop. The weight and height requirements for jacking are constantly increasing [7,8]. However, there is still a certain gap between the current synchronous jacking technology for bridges and the actual engineering requirements.…”