Three-Dimensional Numerical Model for Seismic Analysis of Bridge Systems with Multiple Thin-Walled Partially Concrete-Filled Steel Tubular Columns
Three-Dimensional Numerical Model for Seismic Analysis of Bridge Systems with Multiple Thin-Walled Partially Concrete-Filled Steel Tubular Columns
复制标题
DOI：
10.1061/(asce)st.1943-541x.0002451
复制
发表时间：
2020-01-01
影响因子：
4.1
通讯作者：
Xu, Yan
中科院分区：
文献类型：
--
作者：
Lyu, Fei;Goto, Yoshiaki;Xu, Yan
薄壁部分钢管混凝土（PCFT）柱由于其优异的抗震性能（强度、延性和耗能能力）而被广泛用作高架梁桥的桥墩。为了在设计中考虑这种优异的抗震性能，有必要提供一种分析方法来评估薄壁PCFT柱的极限性能，通过考虑钢管的循环局部屈曲，带裂缝的约束填充混凝土的行为，以及钢管和填充混凝土之间的界面作用。到目前为止，壳-体单元模型分析一直是唯一的数值方法，可以用来考虑这些复杂的行为PCFT柱在一个直接的方式。然而，使用该模型需要不切实际的长计算时间，并经常遇到数值困难，以获得收敛的解决方案时，应用于大型结构系统，如高架梁桥系统与多个薄壁PCFT墩。本研究的目的是提出一个实用的三维纤维为基础的模型与失效段，计算效率高，但准确到足以评估PCFT列的极限行为。该模型通过优化技术进行校正，仅参考由壳-实体单元模型分析计算的每个PCFT柱的面内滞回性能。该模型适用于多墩结构体系在任意多向地震加速度作用下的抗震分析。通过与壳-实体单元模型分析结果以及循环荷载试验和振动台试验结果的对比，验证了所提出的纤维模型在PCFT柱分析中的准确性和数值效率。(C)2019年美国土木工程师协会。
Thin-walled partially concrete-filled steel tubular (PCFT) columns have come to be used as the piers of elevated-girder bridges widely in Japan because of their excellent seismic performance: strength, ductility, and energy dissipation capacity. To consider this excellent seismic performance in design, it is essential to provide an analysis method to assess the ultimate behavior of the thin-walled PCFT columns by considering the cyclic local buckling of the steel tube, the behavior of the confined infilled concrete with cracks, and the interface action between the steel tube and infilled concrete. Up to the present, the shell-solid element model analysis has been the only numerical method that can be used to consider these complicated behaviors of PCFT columns in a direct manner. However, the use of this model requires unrealistically long computation time and often encounters numerical difficulty to obtain convergent solutions when applied to large structural systems such as the elevated-girder bridge systems with the multiple thin-walled PCFT piers. The objective of the present research is to propose a practical three-dimensional fiber-based model with a failure segment that is computationally efficient, yet accurate enough to assess the ultimate behavior of PCFT columns. This model was calibrated by an optimization technique, only referring to the in-plane hysteretic behavior of each single PCFT column calculated by the shell-solid element model analysis. The calibrated model is applicable to the seismic analysis of large structural systems with multiple PCFT piers under arbitrary multidirectional seismic accelerations. The accuracy and numerical efficiency of the proposed fiber-based model in the analysis of PCFT columns were confirmed extensively by the comparison to the shell-solid element model analysis results and the results of tests, such as cyclic loading tests and shake table tests. (C) 2019 American Society of Civil Engineers.