Modeling recommendations for RC and CFST sections in LS-Dyna including bond slip
Modeling recommendations for RC and CFST sections in LS-Dyna including bond slip
复制标题
DOI：
10.1016/j.engstruct.2020.111612
复制
发表时间：
2021-02
影响因子：
5.5
通讯作者：
Mu-Zi Zhao;D. Lehman;C. Roeder
中科院分区：
文献类型：
--
作者：
Mu-Zi Zhao;D. Lehman;C. Roeder
钢筋混凝土(RC)和钢管混凝土(CFST)截面的建模是复杂的，因为模型必须能够捕捉混凝土抗压强度和刚度的退化、约束效应以及钢筋(钢筋或钢管)与混凝土界面的响应。当RC和CFST连接时(例如，RC柱与钢管混凝土桩连接或RC板与钢管混凝土柱连接)，需要对钢管、钢筋、混凝土填充、约束和无约束混凝土、钢筋与混凝土之间的粘结以及管道与混凝土填充之间的粘结进行准确和有效的建模。为了促进对钢筋混凝土和钢管混凝土构件结构体系的理解和设计，开展了一项研究，以评估使用LS-DYNA的各种建模方法的准确性，LS-DYNA具有大量的混凝土模型库和高级的BIND建模功能。利用大型试验数据对钢筋混凝土和钢管混凝土构件及其连接的不同建模方法进行了验证。利用试验数据对四种混凝土模型进行了比较和评价，发现新的混凝土损伤塑性模型能够最准确地模拟混凝土的循环性能。采用粘结材料模型模拟了钢与混凝土之间的粘结滑移行为。模型验证包括损伤模式和测量滞后曲线的比较。总结了在今后的研究和工程实践中推荐使用的建模参数。
Modeling of reinforced concrete (RC) and concrete filled steel tube (CFST) sections is complex, because the model must be capable of capturing degradation of the concrete strength and stiffness in compression, confining effects, the response of the interface of the steel (either reinforcing bar or tube) and concrete. When RC and CFST are connected, (e.g., RC column-to-CFST pile connections or RC slab to CFST column connections), accurate and validated modeling is required for the steel tube, reinforcing steel, concrete fill, confined and unconfined concrete, bond between reinforcing bars and concrete, and bond between the tube and the concrete fill. To advance understanding and design of structural systems using RC and CFST components, a research study was undertaken to evaluate the accuracy various modeling approaches using LS-Dyna, which has a large library of concrete models and advanced modeling capabilities for bond. Large-scale experimental data was used to validate different modeling approaches for the RC and CFST components and their connections. Four concrete models were compared and evaluated using the test data; the new concrete damage plasticity model is found to provide the most accurate simulation of the cyclic behavior of concrete. The bond-slip behavior between steel and concrete was modelled using the cohesive material model. Model validation included comparison of the damage pattern and measured hysteresis curves. A summary of the recommended modeling parameters for use in future research and engineering practice is provided.