用有限元法探讨钢筋混凝土粘结试件-《东南大学学报(自然科学版)》

文章信息/Info

Title:: Study of Reinforced Concrete Bond Specimens by Finite Element Method

摘要:: 本文用有限元法研究钢筋混凝土拉伸及拔出试件。分析中只需根据混凝土和钢筋的基本力学指标而不必用到诸如粘结应力～滑移关系、内部裂纹分市等其他假定。将开裂后的混凝土视为正交异性体,顺裂纹方向的弹性模量取为其初始值E。沿裂纹面的剪切模量G′可以按文中方法确定,垂直裂纹方向的模量E′则可按E及G′确定。虽然在本文的有限元分析中假定混凝土与钢筋直接连接,但两种材料之间的滑移仍可以按本文方法由有限元的计算结果近似求得。文中分析了三个典型的粘结试件。埋置钢筋的总伸长及应变分布,混凝土的应变和粘结应力～滑移关系的计算结果与国外已发表的相应试验数据大致相符。

Abstract:: In this paper, tensile and pull-out reinforced concrete bond specimens are studied by the finite element mathod. The analysis is solely based on the basic mechanical properties of concrete and reinforcing bar, and other additional assumptions, such as distribution of cracks, bond stress-slip relationship, etc., are not necessary. The cracked concrete is considered as an orthotropic body, in which the tangent modulus along the diretion of cracks is taken as its initial value E. The shear modulus G’ on the cracked surface can be determined by a method described in this paper. The tangent modultts in the direction normal to the cracks is then obtained from E and G’. In the analysis, although it is assumed that the concrete is connected directly with the adjacent steel, the slip between both materials can be found approximately from the results of the finite element analysis. Three typical bond specimens are analyzed. The calculated results for the total elongation and the strain distribution of the embedded reinforeing bar, the strains and the distribution of the internal cracks in concrete as well as the bond stress-slip relationship are essentially in good agreement with the experimental data published in foreign literatures.