基于连续体退化组合壳单元的连续箱梁非线性分析

Nonlinear Analysis of Prestressed Concrete Continuous Box Girders Based on CB Degenerated Combined Shell

提出了一种用于预应力混凝土箱梁非线性分析的单元模型,此模型可以方便的模拟结构中存在的普通钢筋、预应力直线钢筋和预应力曲线钢筋。将分层壳单元和大变形杆单元相组合,编制了钢筋混凝土三维非线性分析有限元程序。非线性分析方面考虑了材料和几何非线性,采用TL列式描述几何非线性行为,材料非线性分析包括弹塑性变形、混凝土的开裂和压碎等等。本文提出的单元模型较好的解决了预应力混凝土箱梁分析时曲线配筋模拟的问题。最后给出了2个算例,计算结果与相关软件和试验数据吻合良好。

The present study describes a nonlinear analysis model for the prestressed concrete continuous box girder. This model is capable of simulating the normal steelbar, the linear prestressing steelbar and the curve prestressed steelbar. The model includes the CB layered shell and the large deformation link element, based on the above theory, a programme is completed for nonlinear three dimensional analysis. The material and geometric nonlinearity is considered. The geometric nonlinearity is described based on TL theory. The material nonlinearity includes the elasticity and plastic deformation, the concrete cracking and crushing. The proposed model can be used for the layout of curve prestressed steelbar. Two examples have been analyzed to verify its capability and efficiency. Analytical and experimental results show good agreement with each other.