基于梁格法对斜交箱梁桥的有限元分析

摘要

通过有限元分析软件Midas/Civil,分别对斜交角为15°、30°、45°的两跨预应力混凝土连续箱梁桥的成桥状态进行研究,并同时采用正交梁格法和斜交梁格法做进一步的有限元分析,将两种方法计算得到的反力、位移、内力结果进行了比较,结果表明:随着斜交角度的增大,钝角处的支点反力也在增大,锐角处反而在变小,此时要提高钝角处箱梁的强度,增加配筋;纵梁弯矩峰值逐渐减小,但横向弯矩逐渐增大,此时应当加强横向配筋;采用正交梁格模型时的各纵梁的弯矩峰值相比斜交梁格就越小,正交梁格的优势越明显.%Through finite element analysis software Midas/Civil,this paper has carried on the finite element analysis on the skew Angle of 15 degrees,30 degrees,45 degrees into two span prestressed concrete continuous box girder bridge bridge state adopting orthogonal girder method and skew girder method respectively at the same time.Then comparing the results of the reaction force,displacement and internal force by the two methods.The results showed that:with the increase of skew Angle,there are three kinds of results.One of them is the obtuse fulcrum reaction gradually increasing and the acute Angle of becoming smaller and smaller.So it needs to improve the strength of the box girder and increase the obtuse Angle of reinforcement.One is the Longitudinal beam bending moment peak decreasing,but the lateral bending moment increases gradually.So it should strengthen the transverse reinforcement at the same time.The last result is that orthogonal grillage model of each longitudinal beam bending moment peak is smaller and the advantage of the orthogonal beam grillage model becomes more obvious.