摘要
跨座式单轨轨道梁通常为窄高截面,为避免其混凝土轨道梁线形精度控制难度大、全钢轨道梁噪声、振动和走行面耐候等问题,制作了1榀错位槽口窄高钢-混组合轨道梁1∶3缩尺模型和相应的3个足尺推出试验模型。为研究该类结构的纵向抗剪和竖弯刚度,对比了理论公式、数值模拟和模型试验结果,所得结论如下:(1)错位槽口群钉的抗剪刚度随荷载增大而减小,既有规范公式与试验结果存在较大差异,对该类结构的抗剪刚度仍建议优先采用试验值,其次可采用2013版、2015版规范所得值作为上下限,将该上下限分别用于结构计算并取包络结果;对于焊钉和配筋适量的组合构件,也可采用该文所提公式来估算;(2)组合轨道梁的等效竖弯刚度呈现非线性特征,随着荷载的增大,实测等效刚度先大于后小于理论值;(3)同一截面处钢梁和混凝土板沿高度方向变形不协调,混凝土板应变值显著大于钢梁,难以适用平截面假定。
The track beam of a straddle monorail is typically a narrow-tall section.To avoid the difficulty of the positional precision control of the concrete track beam,and the noise,vibration,and weather resistance of the all-steel track beam,a model(scale of 1∶3)of the narrow-tall composite track beam with interlaced notches and three corresponding full-scale push-out test models was manufactured.To investigate the longitudinal shear and vertical bending stiffness of this type of structure,the results obtained by the theoretical formula,numerical simulation,and model test were compared.The following conclusions were drawn:(1)the shear stiffness of the group nails in the dislocation notches decreased as the load increased.A large difference exists between the existing code and the test results;therefore,it is recommended that the test value is first used for the shear stiffness of this type of structure.The values obtained by the 2013 and 2015 versions of the code can be used as the upper and lower limits,respectively,and these limits can be used for structural calculation and obtaining a envelope result.The proposed formula can also be used to estimate a composite structure with an appropriate amount of rebar and welded nails.(2)The equivalent vertical bending stiffness of the composite track beam is nonlinear.As the load increases,the measured equivalent stiffness is first greater and then less than the theoretical value.(3)At the same section,the steel beam and concrete slab deform incongruously along the height direction.The strain value of the concrete slab is considerably larger than that of the steel beam;therefore,it is difficult to apply the plane-section assumption.
作者
周帅
于鹏
雷军
邓露
谭芝文
邵旭东
Zhou Shuai;Yu Peng;Lei Jun;Deng Lu;Tan Zhiwen;Shao Xudong(China Construction Fifth Engineering Division Co.,Ltd.,Changsha 410004,China;Hunan University,Changsha 410082,China;China Construction Tunnel Construction Co.,Ltd.,Chongqing 401320,China)
出处
《土木工程学报》
EI
CSCD
北大核心
2021年第S01期27-33,共7页
China Civil Engineering Journal
基金
中建股份科技研发课题(CSCEC-2020-Z-43,CSCEC-2021-Z-9,CSCEC-2021-Z-54)
湖南省自然科学基金(2020JJ5632)
关键词
组合结构
错位槽口
窄高截面
等效刚度
非线性
composite structure
interlaced notch
narrow-tall section
equivalent stiffness
non-linearity
