【摘要】 对11个大空心率锥形中空夹层薄壁钢管轻质混凝土试件进行受弯试验研究，分析了试件的破坏形态、承载性能、应变发展及挠度曲线。结果表明:各试件破坏形态、弯矩-跨中挠度曲线趋势基本一致，其变形符合平截面假定，且均具有良好的延性。外钢管径厚比从77增大到154时，无肋和带肋试件的抗弯承载力分别降低34.01%和23.09%;内钢管径厚比从54增大到81时，无肋试件的抗弯承载力降低13.90%。加劲肋增强了内、外钢管与夹层轻质混凝土的协同工作能力，带肋比无肋试件的抗弯承载力提高11.25%～29.66%。采用数值模拟方法对构件的应力发展过程进行分析得出，构件在纯弯荷载作用下的弯矩-跨中挠度曲线可分为三个阶段，即弹性阶段、弹塑性阶段和塑性阶段。提出了适用于大空心率锥形中空夹层薄壁钢管轻质混凝土构件受弯承载力的计算方法，计算结果与试验结果吻合较好。更多还原

【Abstract】 Bending tests were conducted on 11 specimens of tapered lightweight concrete-filled double-skin thin-walled steel tubular members with large hollow ratios. The failure modes,bearing capacity,strain development,and deflection curves of the specimens were analyzed. The results show that the failure modes and bending moment-midspan deflection curves of each specimen are basically the same. The deformation conforms to the plane section assumption and has good ductility.When the diameter-thickness ratio of the outer steel tube increases from 77 to 154,the bending capacity of the specimens without stiffeners and with stiffeners decreases by 34. 01% and 23. 09%,respectively. When the diameter-thickness ratio of the inner steel tube increases from 54 to 81,the bending capacity of the specimens without stiffeners decreases by 13. 90%.The stiffeners enhance the cooperative working ability of the inner and outer steel tubes and the sandwich lightweight concrete. The bending capacity of the stiffened specimens is 11. 25 % ～ 29. 66 % higher than that of the specimens without stiffeners. Analysis of the stress development process in the component using numerical simulation methods shows that the moment-midspan deflection curve under pure bending loads can be divided into three stages: the elastic stage,the elasticplastic stage,and the plastic stage. A calculation method for the bending capacity of tapered lightweight concrete-filled double-skin thin-walled steel tubular members with large hollow ratios was proposed,and the calculation results show good agreement with the experimental results.更多还原