FEM analysis on retrofitted continuous inverted arch structure of sluice floor
XU Huiliang1, SHAO Lin1, WANG Haijun2, ZHOU Yajun2
1.Jiangsu Water Conservancy Engineering Administration Division, Jiangdu, Jiangsu 225200, China; 2. Jiangsu Surveying and Design Institute of Water Resources Co. Ltd., Yangzhou, Jiangsu 225127, China
Abstract:Taking a retrofitting project of sluice floor as an example, the three-dimensional finite element model of the continuous inverted arch structure of a sluice floor is generated. Several construction processes, such as demolition and reconstruction of traffic and operating bridges, floor slab filling, new support structure, load shedding after the walls are simulated by using FEM software to realize the transformation between old and new structures. Based on analysis and comparison among four working conditions, namely old structure, structure demolition, load shedding and structure reconstruction, the effects of working condition on the stress state in the floor are investigated. It is shown that FEM analysis can reflect the variation tendency of stress in the floor in a construction process intuitively and accurately, suggesting the maximum principal tensile stress is mainly located at the edges of holes. The load shedding means can reduce the stress level in the floor occurred in a construction process, as a result, the maximum principal tensile and minimum compressive stresses are lowed by 40% and 55%, respectively, compared with the operating condition without load shedding; thus an abrupt change in the stress will be avoided during construction processes. The inverted arch floor slab filling can relive the stress in the floor, resulting in a 10% reduction in the maximum principal tensile stress. Unfortunately, the minimum principal compressive stress is increased a bit due to the extra-weight of the new structure.
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