Journal of the Society of Disaster Information ISSN:1976-2208(Print) 2671-5287(Online) 한국재난정보학회논문집

Purpose: The steel tower of the main bridge in Section 2 of the 3rd connecting Bridge is the tallest and most slender in Korea. Thus, the vibration stability under dynamic wind loads was evaluated at each construction stage, and geometry control was conducted at every step. Method: Vortex-induced vibrations tend to occur at low wind speeds, which can reduce welding workability between steel tower blocks and cause fatigue damage. To address this, eigenvalue analysis and the calculation of resonance wind speeds were performed for each construction stage to assess the potential for harmful vibrations during construction. During construction, geometry control involves evaluating construction errors from GPS survey results, excluding environmental variables, to determine the adjustment gap between connections when assembling tower leg blocks. Result and Conclusion: The potential for harmful vibrations caused by vortex-induced vibrations was predicted, and real-time monitoring with accelerometers was conducted to assess the feasibility of continuing work. The safety under static and dynamic loads was verified for each construction stage. Geometry control was carried out through procedures involving surveying, data analysis, and error adjustments for each construction stage, and the construction was completed within the allowable construction tolerance.