Analysis of free vibration characteristic of steel-concrete composite box-girder considering shear lag and slip

Abstract

Based on Hamilton principle, the governing differential equations and the corresponding boundary conditions of steel-concrete composite box girder with consideration of the shear lag effect meeting self equilibrated stress, shear deformation, slip, as well as rotational inertia were induced. Therefore, natural frequency equations were obtained for the boundary types, such as simple support, cantilever, continuous girder and fixed support at two ends. The ANSYS finite element solutions were compared with the analytical solutions by calculation examples and the validity of the proposed approach was verified, which also shows the correctness of longitudinal warping displacement functions. Some meaningful conclusions for engineering design were obtained. The decrease extent of each order natural frequency of the steel-concrete composite box-girder is great under action of the shear lag effect. The shear-lag effect of steel-concrete composite box girder increases when frequency order rises, and increases while span-width ratio decreases. The proposed approach provides theoretical basis for further research of free vibration characteristics of steel-concrete composite box-girder.

Keywords

steel-concrete composite box-girder / shear lag effect / shear deformation / slip / free vibration

References

[1] ZhouL-yuService behavior of steel-concrete composite box beams and triaxial nonlinear analysis [D], 2004ChangshaSchool of Civil Engineering: Central South University

[2] GaraF, LeoniG, DeziL. A beam finite element including shear lag effect for the time-dependent analysis of steel-concrete composite decks [J]. Engineering Structures, 2009, 31(8): 1888-1902

[3] GaraF, RanziG, LeoniG. Partial interaction analysis with shear-lag effects of composite bridges: A finite element implementation for design applications [J]. Advanced Steel Construction, 2011, 7(1): 1-16

[4] YamaguchfE, ChaisomphobT. Stress concentration and deflection of simply supported box girder including shear lag effect [J]. Structural Engineering and Mechanics, 2008, 28(2): 207-220

[5] GaraF, RanziG, LeoniG. Simplified method of analysis accounting for shear-lag effects in composite bridge decks [J]. Journal of Constructional Steel Research, 2011, 67(10): 1684-1697

[6] LuoQ-zhi. Geometric nonlinear analysis of curved box continuous girders considering shear lag effect [J]. Advanced Materials Research, 2011, 243/249: 1811-1816

[7] NieJ-g, LiF-X, PanJ-sheng. Practical design method for steel-concrete composite beam considering shear lag effect [J]. Engineering Mechanics, 2011, 28(11): 45-51

[8] VisnjicG, NozakD, KoselF. Shear-lag influence on maximum specific bending stiffness and strength of composite I-beam wing spar [J]. Journal of Aerospace Engineering, 2011, 225(5): 501-511

[9] SunF-f, OresteS, BursiA M. Displacement-Based and Two-Field mixed variational formulations for composite beams with shear lag [J]. Journal of Engineering Mechanics, 2005, 131(2): 199-210

[10] ZhangY-l, LiY-s, JiW-yu. A closed-form solution of load effect and study of shear lag effect for simple steel-concrete composite box beam [J]. Journal of Shijiazhuang Railway Institute, 2009, 22(1): 5-14

[11] LiC-f, DuW-xue. Effect of curvature radius and transverse distribution of load on shear lag for curved box girders [J]. Advanced Materials Research, 2011, 163/167: 1555-1560

[12] GanY-n, ZhouG-chun. Analysis of free vibration characteristics of thin-walled box girder based on energy variation principle [J]. China Journal of Highway and Transport, 2007, 20(1): 73-78

[13] LiuJ-x, MaL, HuQ-an. The research of analysis method of shear lags effect on forced vibration of thin-wall box girder [J]. Journal of Zhengzhou University: Engineering Science, 2008, 29(3): 122-125

[14] ZhangY-j, HuangP-ming. Study on nonlinear PID controller for TCSC in multi machine system [J]. Journal of Zhengzhou University: Engineering Science, 2007, 28(1): 51-55

[15] AyoubA. A force-based model for composite steel-concrete beams with partial interaction [J]. Journal of Constructional Steel Research, 2005, 61(3): 387-414

[16] RanziG, ZonaA. A steel-concrete composite beam model with partial interaction including the shear deformability of the steel component [J]. Engineering Structures, 2007, 29(11): 3026-3041

[17] ZhouW-b, JiangL-z, LiuZ-jie. Closed-form solution for shear lag effects of steel-concrete composite box beams considering shear deformation and slip [J]. Journal of Central South University, 2012, 19(9): 2650-2655

[18] ZhouW-b, JiangL-z, LiuZ-jie. Closed-form solution to thin-walled box girders considering the effects of shear deformation and shear lag [J]. Journal of Central South University, 2012, 19(10): 2810-2816

[19] NieJ-guoSteel-concrete composite structure-test, theory and application [M], 2005BeijingScience Press191-193