钢腹板-混凝土组合箱梁试验研究与有限元分析

进行波形钢腹板-混凝土组合箱梁和平钢腹板-混凝土组合箱梁的模型试验.提出模拟钢腹板-混凝土组合结构的有限元方法,并在大型通用程序ANSYS中实现.有限元计算结果得到了模型梁试验结果的验证,可用于钢腹板-混凝土组合结构的数值分析.试验与数值分析结果表明,两种组合箱梁的总体受力在弹性阶段和弹塑性阶段相似.相对于平钢腹板-混凝土组合箱梁,波形钢腹板-混凝土组合箱梁由于波形钢腹板的折迭效应,其抗变形能力和抗裂性能较相对较弱,但抗剪性能和抗屈曲能力较好.在破坏模式上,波形钢腹板-混凝土组合箱梁属于整体破坏,平钢腹板-混凝土组合箱梁属于平钢腹板局部屈曲破坏,其极限承载力小于波形钢腹板-混凝土组合箱梁.平钢腹板刚度小,在实际工程应用过程中应进行加劲,以防止局部屈曲破坏早于整体破坏的发生,同时也有利于避免施工过程的局部变形.

Experimental and finite element studies on composite box girder with concrete flanges and steel webs

Experiment on composite box girder with concrete flanges and steel webs,including corrugated steel webs and planar steel webs,is conducted.Finite element method for simulating the behavior of such structure is proposed and has been realized by commercial general purpose program ANSYS.The finite element results are validated by the experimental results from the test.It is confirmed that the proposed method is effective to carry out numerical analysis on composite structure with concrete flanges and steel webs.The experiment and finite element results show that the mechanical behavior of the composite box girder with corrugated steel webs is similar with that with planar steel webs in both elastic stage and elastic-plastic stage.Due to the accordion effect of corrugated steel webs,the girder with corrugated steel webs has lower resistance to deformation and cracking than the girder with planar webs,but stronger in the shear capability and buckling capacity.Judging from the failure mode of the experimental girders,the girder with corrugated steel webs is failed globally,while the girder with planar steel webs without stiffening is failed due to the shear local buckling of the web.Additionally,the ultimate load carrying capacity of the girder with planar webs is lower than that with corrugated steel webs.The planar web should be stiffened when it is applied into actual projects in order to avoid its local buckling and local deformation during the course of construction.