拱撑门架承载力试验及有限元分析

为确定单榀拱撑内门架承载力,进行拱撑门架和MF1219门架承载力非线性有限元分析和拱撑门架承载力试验。利用ANSYS软件建立拱撑门架模型和MF1219门架模型,进行特征值屈曲分析,得到各计算模型的承载力。拱撑门架立杆低端铰接,在两立杆上端或上横杆拱形加强杆两端对应位置处进行分级竖向加载,进行了8榀拱撑门架承载力试验。选择JGJ 128—2010《建筑施工门式钢管脚手架安全技术规范》中门架承载力公式进行了单榀拱撑门架承载力计算,并对门架承载力有限元分析、试验和公式计算结果进行了比较。建议:拱撑门架宜立杆直接受力,拱撑门架立杆受力承载力可采用JGJ 128—2010中5.2.1-8a计算,拱撑门架上端横杆受力承载力折减系数宜取0.3。

EXPERIMENTS AND FEM ANALYSIS FOR BEARING CAPACITY OF ARCH SUPPORT PORTALFRAME

In order to determine the bearing capacity of single arch support inner portalframe,experiments on the bearing capacity of single arch support portalframe and nonlinear FEM analysis of the bearing capacity of single arch support portalframe and single MF1219 portalframe were carried out.Models of single arch support portalframe and single MF1219 portalframe were set up using ANSYS software,their eigenvalue buckling analysis was done,and their bearing capacity was obtained.Loading in grades on top ends of two uprights or the corresponding positions of both ends of the arch strengthened rod of single arch support portalframe,in which low ends of two uprights were articulated,8 single arch support portalframes bearing capacity tests were conducted.Different portalframe bearing capacity formula in JGJ 128—2010 Technical Code of Portal Steel Pipe Scalffold for Building Construction was selected,and the single arch support bearing capacity was calculated.After the results of FEM analysis,experiment and calculation of bearing capacity of single portalframe were contrasted,it was proposed that forces should act on top ends of two uprights,the bearing capacity of arch support portalframe for forces acted on top ends of two uprights could be calculated by the formula in 5.2.1-8a of JGJ 128—2010,and the reduction coefficient of the bearing capacity of arch support portalframe for forces acted on top cross bar should be 0.3.