- 摘 要
-
（1 中南林業(yè)科技大學(xué)土木工程學(xué)院， 長沙 410004; 2 湖南大學(xué)土木工程學(xué)院鋼結(jié)構(gòu)研究所， 長沙 410082）
［摘要］為研究主管軸力對N形主方支圓鋼管搭接節(jié)點受力性能的影響，設(shè)計制作了2組共4個節(jié)點試件進(jìn)行極限承載力試驗。試驗結(jié)果表明：當(dāng)節(jié)點幾何參數(shù)、構(gòu)造及支管受力性質(zhì)相同時，主管所受軸壓力較大的節(jié)點，其承載力低于主管軸壓力較小的節(jié)點。以試驗為基礎(chǔ)，建立了考慮主管軸力影響的節(jié)點有限元分析模型，計算得到了主管軸力對該類節(jié)點承載力的影響參數(shù)，將其與按《鋼結(jié)構(gòu)設(shè)計標(biāo)準(zhǔn)》（GB 50017—2017）中圓管節(jié)點及矩形管節(jié)點主管軸力對節(jié)點承載力影響的參數(shù)公式計算結(jié)果進(jìn)行了對比。研究表明：主管軸拉力對N形主方支圓鋼管搭接節(jié)點的承載力影響較小，可以忽略，但主管軸壓力對節(jié)點承載力影響較大，且規(guī)范參數(shù)公式對該類節(jié)點并不適用。通過回歸分析，提出了主管軸力對N形主方支圓鋼管搭接節(jié)點承載力影響參數(shù)的建議公式，為該類節(jié)點承載力計算提供參考。
［關(guān)鍵詞］N形主方支圓鋼管搭接節(jié)點； 承載力； 主管軸力； 影響參數(shù)； 建議公式
中圖分類號：TU391-3文獻(xiàn)標(biāo)識碼：A文章編號：1002-848X(2018)22-0007-08
Study on influence of chord axial force on bearing capacity of overlapped N-joints with square chord and circular braces
Yuan Zhishen1， Shu Xingping2， Hu Xibing1
（1 College of Civil Engineering, Central South University of Forestry and Technology, Changsha 410004, China;2 Steel Structural Institute of Civil Engineering College, Hunan University, Changsha 410082, China）
Abstract:To study the influence of chord axial force on bearing capacity of overlapped N-joints with square chord and circular braces, four specimens in two groups were tested under monotonic loading. The test results show that when the geometric parameters, the details of joints and the nature of brace force are the same, the bearing capacity is lower with higher chord axial compression than that with lower chord axial compression. Based on the experiment, nonlinear finite element analysis models considering the chord axial force were established, and the influence parameters of the chord axial force were obtained. Meanwhile, a comparison was carried out between the FEA results and the results by design equations of circular hollow section and rectangular hollow section joints in Standard for design of steel structures(GB 50017—2017). The research indicates that the chord axial tension has little effect on the bearing capacity of N-joints with square chord and circular braces, but the chord axial compression has obvious effect on the bearing capacity of this joint. However, it reveals that the design equations of influence parameter of the chord axial force for CHS or RHS joints are not suitable for N-joints with square chord and circular braces. By applying multivariate regression analysis, a formula of influence parameter of the chord axial force for N-joints with square chord and circular braces is proposed, which provides the reference for the calculation of bearing capacity of this joints.
Keywords:overlapped N-joints with square chord and circular braces; bearing capacity; chord axial force; influence parameter; proposed formula
*國家自然科學(xué)基金項目（51608544），湖南省教育廳優(yōu)秀青年基金（14B187），中南林業(yè)科技大學(xué)引進(jìn)高層次人才科研啟動基金（2013RJ013）。
作者簡介：袁智深，博士，講師，Email：36894743@qq.com。
