钢管自密实混凝土轴压构件静力性能的有限元模拟与机理分析

Finite Element Simulation and Mechanism Analysis on Static Performance of the Self-Consolidating Concrete Filled Steel Tubular Member under Axial Compression

目的对钢管自密实混凝土轴压构件的静力性能进行有限元模拟,进一步了解其工作机理分析,为辽宁省相关地方标准的编制提供依据.方法在试验研究的基础上,采用有限元法建立分析模型并模拟试件的轴力-中截面挠度曲线和破坏模态,验证有限元分析模型可靠,以此模型深入研究了钢管自密实混凝土轴压构件中钢管和混凝土应力和应变等的分布规律.结果典型算例的分析结果表明,圆试件钢管与混凝土的相互作用力沿圆周分布均匀,而方试件角部区域钢管与核心混凝土的相互作用最大;随着离中截面距离的增加,钢管与核心混凝土之间的作用力逐渐减小.粘接强度对试件的承载力和相互作用力影响不大.结论对于混凝土浇筑强度达96 MPa的钢管自密实混凝土轴压构件的承载力,仍可采用钢管普通混凝土构件的计算公式.钢管自密实混凝土构件与钢管普通混凝土构件在静力性能方面没有本质区别.

In order to investigate the static performance of the axially compressed self-consolidating concrete filled steel tubular members and to provide theoretical fundamental for the local code of Liaoning province,an analysis model was established and the load versus mid-height cross-section deflection curves and deformation models of the specimens were simulated by using finite element method on the basis of experimental study.It was found that the proposed model was effective.The static performance,distributions of stress,strain for the steel tube and the concrete of the member were studied deeply by using this model.Analysis results of the typical calculation indicates that the interaction force between the steel tube and the concrete distributes uniformly along the circular direction of the circular specimens,while the interaction force between the steel tube and the concrete focus on the corner and nearby of the square specimens.The interaction force between the steel and the concrete reduces gradually with the increase of the distance to the mid-height cross-section.The adhesive strength has little influence on load bearing capacity and the interaction force of the specimens.Also,the load bearing capacity calculation formula for normal concrete filled steel tube can be used for self-consolidating concrete filled steel tube with concrete whose cubic strength is of 96 MPa.There is no essential difference between self-consolidating concrete filled steel tube and normal concrete filled steel tube with respect to the static performance.