建筑结构学报2025，Vol.46Issue(6)：128-140,13.DOI:10.14006/j.jzjgxb.2024.0082
三肢曲线不锈钢管混凝土桁架受弯性能研究
Study on flexural behavior of three-chord curved concrete-filled stainless steel tubular truss
摘要
Abstract
The three-chord curved concrete-filled stainless steel tubular truss(CCFSST truss)has a wide range of applications in large-span space structure roofs.Currently,there is limited research on the flexural behavior of such trusses.To address this issue,a total of four specimens were tested to study the influence of curvature coefficient(f/L is 0,0.1,0.2)and whether the chords are filled with concrete on the flexural performance of CCFSST truss.Failure modes,load-deformation relationship,flexural capacity,flexural stiffness,and the strain development were analyzed.The experimental results show that,the flexural capacity and stiffness of the CCFSST trusses increase with the curvature coefficient.However,once the coefficient reaches 0.2,bending-shear failure occurs,leading to a decrease in load-carrying capacity.Trusses with concrete-filled chords exhibit significant improvements in flexural capacity,flexural stiffness,and ductility when compared to hollow stainless steel tubular strusses.The strain of chord at mid-span of CCFSST truss is smaller than that of the straight truss,the stress of braces decreases from the support to the mid-span.The strain of the most critical braces decreases with increasing curvature coefficient.A finite element analysis(FEA)model was developed for parametric analysis.The results show that the flexural capacity of the CCFSST truss is not affected by the angle between the chord and the brace,but the flexural stiffness and capacity of the CCFSST truss increase with the increase of the height-to-span ratio.In the case of the curvature coefficient,as it increases,the flexural stiffness and capacity of the CCFSST truss first increase and then decrease.A method incorporating the curvature coefficient was proposed to calculate the flexural capacity of the CCFSST truss under the condition where the bottom chord acts as the critical member.The modified formula demonstrates strong accuracy,with an average ratio of 0.979 between the calculated and experimental results.关键词
不锈钢管混凝土/曲线桁架/受弯性能试验/受弯承载力/抗弯刚度Key words
concrete-filled stainless steel tube/curved truss/flexural behavior test/flexural capacity/flexural stiffness分类
建筑与水利引用本文复制引用
郑莲琼,刘大海,周子程,郑永乾..三肢曲线不锈钢管混凝土桁架受弯性能研究[J].建筑结构学报,2025,46(6):128-140,13.基金项目
国家自然科学基金项目(51308119). （51308119）
