摘要
自由曲面铝合金单层网壳中的构件通常使用板式节点进行连接.为了满足板式节点的装配需求,需要将板式节点的节点板冲压成具有多个拱度的复杂形状.然而,回弹现象降低了板件的成形精度,且会造成节点装配困难.为了提高节点板的成形精度,有必要对节点板的冲压回弹进行准确预测和有效补偿.首先,对6组多拱度铝合金节点板试件进行了冲压成形试验,通过3D扫描测量了板件的残余拱度,并计算得到板件的回弹量.其次,采用显式动力算法与隐式静力算法结合的混合算法对板件的冲压回弹过程进行有限元分析,分析得到的板件回弹量与试验值的相对误差平均值仅有4.31%.再次,基于1500组节点板冲压回弹有限元分析结果,建立了回弹预测的响应面模型,该模型的决定系数达到了0.988,表明该模型具有较高精度.最后,基于回弹预测响应面模型,提出了多拱度铝合金节点板的回弹补偿方法.使用该方法对20组具有不同几何参数和拱度组合的节点板进行试设计,结果表明该方法能够对板件的回弹进行有效补偿.
In free-form aluminum alloy single-layer latticed shells,the members rely on the gusset joints to connect.To meet these assembly requirement of the gusset joint,the joint plates need to be stamped into complex shapes with multiple cambers.However,the springback phenomenon reduces the forming accuracy and may cause difficulty in joint assembly.To improve the forming accuracy of the joint plates,it is crucial to predict and compensate for the springback.Firstly,forming experiments were conducted on 6 joint plate specimens,the residual cambers were scanned with a 3D scanner,and the springback values were calculated.Secondly,a mixed algorithm of explicit dynamic and implicit static algorithm was used for the simulation of the springback process on the joint plates.Compared with the experiment springback values,the simulated values only had a mean relative error of 4.31%.Subsequently,response surface models for springback prediction were constructed based on 1500 numerical simulation results,and the coefficient of determination of the model was 0.988,indicating a high accuracy.Finally,based on the springback prediction response surface model,a springback compensation method for multi-camber aluminum alloy gusset joint plates was proposed and validated with 20 numerical examples.The method was used to design 20 groups of joint plates with different geometric parameters and camber combinations.The results show that the method can effectively compensate the springback of the plates.
作者
郭小农
李根
曾强
钟芬达
GUO Xiaonong;LI Gen;ZENG Qiang;TRIVANA Vanda(College of Civil Engineering,Tongji University,Shanghai 200092,China;School of Mechanics and Civil Engineering,China University of Mining and Technology,Xuzhou 221116,China;Build King Construction Limited,Hongkong,999077,China)
出处
《湖南大学学报(自然科学版)》
北大核心
2025年第5期28-40,共13页
Journal of Hunan University:Natural Sciences
基金
国家自然科学基金资助项目(51478335)。
关键词
铝合金
板式节点
回弹预测
回弹补偿
响应面法
aluminum alloy
gusset joint
springback prediction
springback compensation
response surface method
