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为了评估节点刚度对网壳极限承载能力的影响,建立了一种能同时考虑节点刚度(弯曲刚度、轴向刚度、扭转刚度与剪切刚度)和节点大小的力学模型.借鉴节点正则化弯曲刚度指标κb的概念,建议采用正则化轴向刚度κa、正则化扭转刚度κt与正则化剪切刚度κs来衡量节点的轴向、扭转及剪切刚度.经过数值计算,主要得出如下结论:节点弯曲刚度对网壳承载能力的影响程度与κb的大小紧密相关,随着κb的减小,网壳极限荷载逐渐降低,若κb小于10,网壳极限荷载会显著降低;节点轴向刚度明显影响着网壳的整体刚度,随着κa的减小,在弹性阶段内荷载位移曲线斜率明显减小;节点扭转刚度对网壳极限荷载影响与节点抗弯刚度有关,随着节点抗弯刚度的减小,扭转刚度的影响逐渐增加;节点剪切刚度对网壳极限荷载的影响程度也与κb紧密相关,当κb大于10时,随着κs的降低,极限荷载首先缓慢降低而后迅速下降;节点大小对具有较大节点弯曲刚度的网壳的极限荷载影响更加明显;节点偏差对半刚接网壳的承载能力影响显著,整体上而言,节点弯曲刚度越小,节点偏差的影响越大.“,”A mechanical model is developed to evaluate the effect of joint stiffness (including bending stiffness,axial stiffness,torsional stiffness and joint shear stiffness) and joint size on load-carrying capacity of single-layer reticulated dome.Meanwhile,referring to normalized joint bending stiffness index κb,normalized joint axial stiffness κa,normalized joint torsional stiffness κt and normalized joint shear stiffness κs are suggested to quantify joint axial,torsional and shear stiffness,respectively.The main conclusions obtained are summarized as follows:the effect of joint bending stiffness on load-carrying capacity of reticulated dome has a close relationship to κb.With the decrease of κb,the limit load gradually decreases.If κb is less than 10,the joint bending stiffness remarkably reduces the load-carrying capacity.Overall rigidity of reticulated dome is remarkably influenced by joint axial stiffness,and slope of load-displacement curve gradually becomes gentle in the elastic range with the decrease of κa.The effect of joint torsional stiffness κt on the load-carrying capacity of reticulated dome is influenced by κb,and the effect will increase with the decrease of κb.The effect of joint shear stiffness on load-carrying capacity of reticulated dome is closely related to κb.With the decrease of κs,the limit load firstly reduces slightly then drops suddenly for reticulated dome with κb larger than 10.Joint size has more obvious influence on load-carrying capacity of reticulated dome with large value of κb than the one with small value of κb.Overall,the load-carrying capacity of reticulated dome with weak joint bending stiffness is more sensitive to nodal deviation.