摘要
为了揭示中墩斜支承对连续箱梁力学性能的影响,本文考虑约束扭转和竖向挠曲耦合作用,建立了斜支承连续箱梁的力法方程,并获得了内力和变形的解析式。选取斜支承两跨连续箱梁为数值算例,分别计算了竖向对称和偏心均布荷载作用下的内力和变形,并用ANSYS软件计算了控制截面的弯矩。计算结果表明,本文方法计算的弯矩与ANSYS计算值吻合良好;与常规的连续箱梁相比,在竖向对称均布荷载作用下,斜支承连续箱梁的挠度减小不显著,而在竖向偏心均布荷载作用下,斜支承连续箱梁的挠度有显著变化,斜交角为45°时,挠度改变量可达到25%以上;无论是在竖向对称还是偏心均布荷载作用下,斜支承连续箱梁的扭转角均大于常规连续箱梁的扭转角,二次扭矩和双力矩都仅在斜支承点附近的局部范围出现较大值。
For revealing the influence of skew supports of inner piers on mechanical properties of a continuous-box-girder,the force method equation of a skewly supported continuous box girder was established by considering the coupling of constrained torsion and vertical flexure in this paper,and the analytic formula of internal force and deformation were derived.A two-span skewly supported continuous box girder was adopted as the numerical example.The internal force and deformation were calculated for the box girder subjected to vertical symmetric and eccentric uniform loads,respectively.The bending moment in the governing sections was also calculated by using ANSYS software.The results show that the bending moment calculated by the presented method is in good agreement with that calculated by ANSYS.Compared with a regular continuous box girder,the deflection of the box girder subjected to the vertical symmetric uniform load is not decreased remarkably,however,the variation of deflection of the box girder subjected to the vertical eccentric uniform load is remarkable and can get over 25% more than the deflection,when the skew angle is 45°.The twist angle of the box girder is larger than that of a regular continuous box girder and the secondary moment and bi-moment have larger values only in a small range near the skew supports,either under vertical symmetrical or under vertical eccentric uniform load.
作者
魏彦红
张元海
WEI Yan-hong;ZHANG Yuan-hai(School of Civil Engineering,L.anzhou Jiaotong University,Lanzhou 730070,China)
出处
《计算力学学报》
CAS
CSCD
北大核心
2022年第1期99-104,共6页
Chinese Journal of Computational Mechanics
基金
国家自然科学基金(51968040)资助项目。
关键词
连续箱梁
斜支承
斜交角
二次扭矩
双力矩
continuous box girder
skew supports
skew angle
secondary moment
bi-moment
