Abstract

With the rapid development of engineering constructions, especially transportation facilities, the structural models for the simulation of large-scale structures shall be eventually enhanced for predicting the complete three-dimensional stress and strain fields in reinforced concrete-made components. This paper proposes a component-wise approach for the modeling of reinforced concrete structures in which steel rebars and the concrete part are considered as two independent one-dimensional entities. Lagrange polynomials are used to express the cross-section deformations and different component-wise subdomains are joined by simply imposing displacement continuity at the chosen Lagrange points along the component boundary. The Finite Element (FE) method is applied to provide numerical solutions whereas Carrera Unified Formulation (CUF) is used to generate the related stiffness matrices in a compact and straightforward way. The classical case of homogenized beam solutions, as well as the one in which a virtual layer is associated with the steel zones, are implemented too. The three solutions are compared for a number of reinforced concrete beam problems, from single to double reinforced beam, including a T-shape cross-section. A final study considering transverse stiffeners (steel stirrups) is investigated. These stiffeners are modeled component-wise as well. Results clearly show the advantages and superiority of the component-wise FE-CUF based model to completely capture the three-dimensional strain and stress states, including shear ones, of reinforced concrete structures.

摘要

随着工程建设，特别是交通设施的快速发展，大型结构模拟的结构模型最终将得到增强，以预测钢筋混凝土构件中完整的三维应力应变场。本文提出了一种基于构件的钢筋混凝土结构建模方法，其中钢筋和混凝土部分被视为两个独立的一维实体。拉格朗日多项式用于表示横截面变形，并且通过在所选拉格朗日点沿组件边界简单地施加位移连续性来连接不同的组件子域。有限元 (FE) 方法用于提供数值解，而卡雷拉统一公式 (CUF) 用于以紧凑和直接的方式生成相关的刚度矩阵。均质梁解决方案的经典案例，以及虚拟层与钢区相关联的案例也得到了实施。这三种解决方案针对许多钢筋混凝土梁问题进行了比较，从单钢筋梁到双钢筋梁，包括 T 形横截面。研究了考虑横向加强筋（钢箍筋）的最终研究。这些加强筋也是按组件建模的。结果清楚地表明了基于组件的 FE-CUF 模型的优势和优势，可以完全捕捉包括剪切在内的三维应变和应力状态，