摘要
单板焊接空心球节点常用做弦支穹顶上部结构连接拉杆或拉索的节点,单板主要承受拉力并传递至焊接空心球,为了满足工程设计的要求,需对其受拉承载性能进行研究.通过试验,研究了不同参数的单板焊接空心球节点轴拉状态下的受力性能和破坏机理,建立有限元模型并进行验证,该模型能较好地反映单板焊接空心球节点轴拉性能,通过有限元模型参数化分析揭示了节点尺寸、加劲肋、单板尺寸等参数对其力学性能的影响规律,并提出单板焊接空心球轴拉承载力计算公式.研究结果表明:单板焊接空心球在轴拉作用下为应力集中导致的剪切强度破坏,破坏发生在单板端部与空心球连接处,表现为焊接空心球被撕裂;有限元应力云图得出破坏时沿着单板平面内拉力方向的剪应力起主要作用;单板焊接空心球节点的受拉承载力随单板宽度及空心球壁厚的增大而明显增大,空心球直径的增大会使承载力略有降低,单板的厚度增加使节点承载力略有提高,单板的高度对节点承载力的影响较小,空心球内设置加劲肋能使承载力提高至少20%;基于参数化提出的单板焊接空心球节点的受拉承载力计算公式能简便地计算出单板焊接空心球节点的承载力,相对误差在±15%以内,满足工程设计误差要求.研究工作可为今后外接单板的焊接空心球节点分析设计提供参考.
Single-plate welded hollow spherical joints are commonly used to link bridle rods or cables to suspendome superstructures.The tension is mostly carried by the single board and transmitted to the welded hollow sphere.It is vital to investigate its tensile bearing performance to meet the requirements of the engineering design.The mechanical performance and failure mechanisms of single-plate welded hollow spherical joints with different parameters under axial tensile state were experimentally investigated.A finite element model was established and verified to predict the axial tensile performance of single-plate welded hollow spherical joints.The parametric analysis of finite element models revealed the law of the effect of parameters,such as joint size,stiffening ribs,and single-plate size,on their mechanical properties,and calculation formulas of the axial tensile bearing capacity of single-plate welded hollow spherical joints were proposed.The results show that under axial tension,the single-plate welded hollow spherical joints develop shear strength failure due to stress concentration;the failure occurred at the connection between the end of the single-plate and hollow sphere,which was characterized by tearing of a welded hollow sphere.The stress nephogram showed that shear stress along the tension direction in the single plate was the primary cause of failure.The tensile capacity of a welded hollow spherical joint significantly increases as the width of the single-plate and thickness of the hollow sphere increase.The bearing capacity gradually decreases as the diameter of the hollow sphere increases.The bearing capacity of the joints will be slightly increased as the thickness of the single-plate increases.The height of the single-plate has little influence on the bearing capacity of the joints.Stiffeners installed in the hollow sphere can increase its bearing capacity by at least 20%.Based on the parametric analysis,the calculation formula for the tensile capacity of single-plate welded hollow spherical joints can simply calculate the bearing capacity of single-plate welded hollow spherical joints with a relative error within±15%,meeting the requirement of engineering design error.The research findings may be used to guide the analysis and design of welded hollow spherical joints with a single external plate in the future.
作者
陈志华
蔡汝锐
刘红波
温锁林
Chen Zhihua;Cai Rurui;Liu Hongbo;Wen Suolin(School of Civil Engineering,Tianjin University,Tianjin 300072,China;Key Laboratory of Coast Civil Structure Safety of Ministry of Education(Tianjin University),Tianjin 300072,China;School of Civil Engineering,Hebei University of Engineering,Handan 056038,China)
出处
《天津大学学报（自然科学与工程技术版）》
EI
CAS
CSCD
北大核心
2024年第1期1-10,共10页
Journal of Tianjin University：Science and Technology
基金
国家重点研发计划(2022YFB4200700).
关键词
单板焊接空心球节点
数值模拟
轴拉性能
承载力
single-plate welded hollow spherical joint
numerical simulation
axial tensile performance
loadbearing capacity
