摘要A theory for directly identifying shrinkage and creep in a structure, along with an embedded self-identification system, is proposed. The theory and system aim to obtain accurately the time-dependent regularity of shrinkage and creep in an actual structure. Moreover, they aim to improve the prediction accuracy for long-term deflection. A preliminary validation is then conducted through an experimental beam test. Results show that the identified creep coefficient curve of the test beam can represent the real creep in the structure better by using the same calculation method for structure deformation. In addition, the calculated mid-span deformation of the beam that uses a self-identification creep coefficient prediction approach is closer to the measured deformation than the theoretically predicted results. Therefore, the proposed embedded concrete creep self-identification system effectively identifies shrinkage and creep in a structure, and significantly improves the accuracy of predicting deformation in concrete structures, thus providing a new method for predicting long-term deflection in long-span beam bridges.
Abstract:A theory for directly identifying shrinkage and creep in a structure, along with an embedded self-identification system, is proposed. The theory and system aim to obtain accurately the time-dependent regularity of shrinkage and creep in an actual structure. Moreover, they aim to improve the prediction accuracy for long-term deflection. A preliminary validation is then conducted through an experimental beam test. Results show that the identified creep coefficient curve of the test beam can represent the real creep in the structure better by using the same calculation method for structure deformation. In addition, the calculated mid-span deformation of the beam that uses a self-identification creep coefficient prediction approach is closer to the measured deformation than the theoretically predicted results. Therefore, the proposed embedded concrete creep self-identification system effectively identifies shrinkage and creep in a structure, and significantly improves the accuracy of predicting deformation in concrete structures, thus providing a new method for predicting long-term deflection in long-span beam bridges.
谢峻, 曾丁, 郑晓华. 基于收缩徐变自辨识的大跨径梁桥长期挠度预测研究[J]. Journal of Highway and Transportation Research and Development, 2014, 8(2): 47-50.
XIE Jun, ZENG Ding, ZHENG Xiao-hua. Predicting Long-term Deflection in Large-span Beam Bridges Based on Creep Self-identification. Journal of Highway and Transportation Research and Development, 2014, 8(2): 47-50.
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