Chapter 3 Analysis of Variation Rate of Displacement to Temperature of Service Stage Cable-Stayed Bridge Using Temperatures and Displacement Data Hyun-Joong Kim Abstract Because stage cable-bridge have long spans and large members, their movements and geometrical changes by temperatures tend to be bigger than those of small or medium-size bridge. Therefore, it is important for maintenance engineers to monitor and assess the effect to temperature on the cable-supported bridges. To evaluate how much the superstructure expands or contracts when subjected to changes in temperature is the first step for the maintenance. Thermal movements of a cable-stayed bridge in service are evaluated by using long-term temperatures and displacements data. Keywords Cable-stayed bridge • Thermal movements • Temperature effect • Correlation analysis 3.1 Introduction Since cable-supported bridges are long and sizable, their movement and transportation amount are quite considerable compared to those of general bridges. Thus, in order for the maintenance of cable-supported bridges, it is important to analyze and evaluate the influence of temperature on the existing bridges; in terms of such temperature evaluation, assessing elastic superstructures of bridges depending on the change in temperature is known to be the most basic analyzing techniques. Recently, there are a variety of ongoing research projects to evaluate the structures more precisely as the existing period of cable-supported bridges getting extended and the amount of their accumulated data is increasing [2–4]. In our research, in order to study the influence of temperature on cable-supported bridges, we employed the previous methods such as using an expansion displacement meter or single measuring method with data gathered from Global Navigation Satellite System (GNSS). Then, based on the cases that evaluated temperature expansion behaviors using different datasets to enhance their statistical reliability, we measured the expansion per unit temperature using the temperature data and the GNSS displacement data of existing cable bridges and confirmed the structural integrity of the bridges through the comparison between our results and theoretical values. 3.2 The Subject Bridge and Data Collection Method 3.2.1 Subject Bridge The bridge used for this research is Cheong-Poong Dae-Kyo (Bridge) located in Jechun, Choong-Cheong-Book-Do, which is a 5-consecutive-span complex cable-stayed bridge with the full length of 472 m (center: 327 m, side span: 57.5 m, abutment: 30 m) and width of 13 m and has RC cross sections for its side spans and composite cross sections consisting of precast concrete floor slap and I-shaped structural steel cross sections for its main spans. Its tower has a H-shaped concrete cross section with the height of 103 m and was completed in May 2012; it is currently under the management of Structural Health Monitoring System (SHMS). H.-J. Kim( ) EJ Tech Co., Ltd., Seokjeong B/D, 10, migeum-ro 33 beon-gil, Bundang-gu, Seongnam-si, Gyeonggi-do, Republic of Korea e-mail: hjkim@ejtech.net © The Society for Experimental Mechanics, Inc. 2017 J. Caicedo, S. Pakzad (eds.), Dynamics of Civil Structures, Volume 2, Conference Proceedings of the Society for Experimental Mechanics Series, DOI 10.1007/978-3-319-54777-0_3 21
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