开口组合曲梁焊钉剪力分布规律研究

STUD SHEAR DISTRIBUTION IN COMPOSITE CURVED BEAM WITH OPEN SECTION

采用空间板壳和实体单元详细模拟了组合曲梁的钢板和混凝土,用考虑3个方向位移的弹簧单元模拟组合梁中的每个焊钉连接件。结合一工程实例,用空间有限元模型详细计算了开口组合曲梁的受力,得到焊钉在组合梁中的剪力分布。组合曲梁的焊钉不仅有切向剪力还有法向剪力,其中切向剪力在梁端部大中间小,而法向剪力是在梁中间大两端小。当曲梁中心弧长与曲率半径比值小于0.5时,可以忽略法向剪力分量,用焊钉切向剪力近似代替其总剪力是可行的。当组合曲梁沿梁长度有多排焊钉时,相同截面处,内侧、外侧焊钉受力不均匀,外侧要大于内侧,而且随着弧长与半径比值的增大这种不均匀程度增大,在设计中应当引起足够的重视。

Spatial shell elements and solid elements were adopted to simulate steel plates and the concrete deck of a composite curved beam;also spring elements with 3-dimension displacement were used to simulate each stud of the composite beam.Based on actual work,the mechanical behavior of a composite curved beam with open sections was calculated by the finite element method,and the stud shear distribution in the composite curved beam was obtained.The studs in the composite curved beam not only burden tangential shear forces but also burden normal shear forces,where the tangential shear forces are large at the ends of the beam and small in the mid-span along the beam length,and the normal shear forces are large in the mid-span and small at the beam ends along the beam length.When the ratio of the arc length of the central line in the curved beam to the radius of the arc is less than 0.5,it is feasible to substitute the stud tangential shear force for its resultant shear force approximately and neglect the component of the normal shear force.The arrayed Multi-row studs along the length of the curved composite beam,the non-uniformity of shear forces exists in the both inner row and outer row stud of the same section,and the shear force in the outer row stud is larger than that of in the inner row stud.The degree of the non-uniformity is increased by increasing the ratio of the arc length of the central line in the curved beam to the radius of the arc,which is worthy of enough attention in design.