基于Galerkin法的新型波形钢腹板箱梁桥动力特性研究  

Dynamic Characteristics of New Type Composite Box Girder Bridge with Corrugated Steel Webs Based on Galerkin Method

作　　者：冀伟[1] 温凯康 罗奎 JI Wei;WEN Kaikang;LUO Kui(School of Civil Eng.,Lanzhou Jiaotong Univ.,Lanzhou 730070,China;School of Civil Eng.,Hunan Univ.,Changsha 410082,China)

机构地区：[1]兰州交通大学土木工程学院,甘肃兰州730070 [2]湖南大学土木工程学院,湖南长沙410082

出　　处：《工程科学与技术》2022年第3期131-138,共8页Advanced Engineering Sciences

基　　金：国家自然科学基金项目(51708269,51868039);甘肃省科技重点研发计划项目(20YF3FA039);甘肃省自然科学基金项目(21JR7RA315);兰州市人才创新创业项目(2021–RC–39)。

摘　　要：为科学合理地分析新型波形钢腹板组合箱梁桥的弯曲振动频率,综合考虑波形钢腹板的剪切变形效应和箱梁的剪力滞效应,运用Galerkin法和Hamilton原理推导该桥型的自由振动控制微分方程和自然边界条件。根据自然边界条件,求解出剪切变形效应和剪力滞效应影响下新型波形钢腹板组合箱梁桥的弯曲振动频率计算公式,将公式的计算结果与试验实测结果和ANSYS 3维有限元结果进行对比,并对弯曲振动频率的影响因素进行分析。结果表明:弯曲振动频率计算公式的计算结果与试验实测结果和ANSYS有限元结果吻合良好,验证了所推导的弯曲振动频率计算公式的正确性。弯曲振动频率随高跨比的增大而增大,当高跨比小于0.05时,弯曲振动频率的增幅较为平缓;当高跨比大于0.05时,弯曲振动频率的增幅较为显著。弯曲振动频率随宽跨比的增大而增大,但整体增幅不明显。弯曲振动频率随波形钢腹板厚度的增加而增大,频率阶数越高,增幅越显著。箱梁剪力滞效应对弯曲振动频率影响较小,前5阶弯曲振动频率的最大误差仅为6.73%;波形钢腹板的剪切变形对弯曲振动频率影响较大,前5阶弯曲振动频率的最大误差高达51.18%。To scientifically and reasonably analyze the bending vibration frequency of the new type composite box girder bridge with corrugated steel webs,taking into account the shear deformation effect of corrugated steel webs and the shear lag effect of box girder,the Galerkin method and the Hamilton principle were used to deduce the free vibration control differential equation and natural boundary conditions of the bridge type.According to the natural boundary conditions,the calculation formula of the bending vibration frequency of the new type composite box girder bridge with corrugated steel webs under the influence of shear deformation effect and shear lag effect was solved.The results were compared with the measured results and ANSYS finite element results,and the influencing factors of the bending vibration frequency were analyzed.The results showed that the calculation results of the bending vibration frequency were in good agreement with the measured results and the ANSYS finite element results,which verified the correctness of the derived frequency calculation formula.The bending vibration frequency increased with the increase of the high-span ratio.When it was less than 0.05,the increase of the bending vibration frequency was relatively gentle.When the height-span ratio was greater than 0.05,the increase of the bending vibration frequency was more significant.The bending vibration frequency increased with the increase of the width-span ratio,but the overall increase was not obvious.The frequency increased with the increase of the thickness of the corrugated steel web,and the higher the order,the more significant the increase.The shear lag effect of the box girder had little effect on the bending vibration frequency,and the maximum error of the first 5 orders was only 6.73%.The shear deformation of the corrugated steel webs had a great influence on the bending vibration frequency,and the maximum error of the first five orders was as high as 51.18%.

关 键 词：组合箱梁 波形钢腹板 弯曲振动频率 剪切变形 剪力滞 GALERKIN法 

分 类 号：U441.3[建筑科学—桥梁与隧道工程]