波形钢腹板连续箱梁的动力特性

Dynamic Characteristics of Composite Box Girder with Corrugated Steel Webs

为了详细研究波形钢腹板连续箱梁的动力特性,设计制作了此类型的模型试验梁,采用DHDAS动态信号测试分析系统对其动力特性进行了实测,根据实测数据识别出各阶竖向弯曲振动的模态及振动频率,并建立ANSYS有限元模型对其动力特性进行了计算和分析。模型试验梁的有限元分析结果与实测结果的差别较小。因此,实际中采用本文的有限元建模方法可以获得比较高的精度。同时还研究了不同位置的横隔板对波形钢腹板预应力混凝土连续箱梁的动力特性的影响,分析结果表明,支座横隔板对箱梁动力特性的影响最大,而中横隔板基本不影响箱梁的动力特性。因此在实际中,当支座横隔板的设置足以抵抗截面畸变变形的条件下,可以适度减少中横隔板的数量,从而节约桥梁建设成本。

In order to study the dynamic characteristics of continuous box girder with corrugated steel webs in detail,the test beam model of prestressed concrete continuous box girder with corrugated steel webs was designed and manufactured.The DHDAS dynamic signal test and analysis system was adopted to test its dynamic characteristics for identifying the vertical bending vibration modes and the vibration frequencies of various orders,and the ANSYS finite element model was built to calculate and analyse the dynamic characteristics.The comparison between measured result and finite element analysis result of model test beam shows that the gap is small.Therefore,this finite element modeling technique can obtain a high accuracy.The effect of different positions of the diaphragms on the dynamic behavior of PC continuous box girder with corrugated steel webs was also studied.The analysis results of different schemes shows that the bearing diaphragms have the greatest influence on dynamics characteristics of the dynamic characteristics of the box girder,while mid-diaphragms have little influence basically.Therefore,in practice,when bearing diaphragm setting can resist the distortion deformation,the number of the diaphragm can be moderately reduced to save the bridge construction cost.