FRP-混凝土-钢双壁空心管的截面弯矩-曲率全曲线

为研究纤维增强复合材料(FRP)-混凝土-钢双壁空心管的抗弯性能,完成了3根试件的抗弯试验。采用条带法计算了3个试件和12个双壁空心管计算模型的截面弯矩-曲率曲线;推导了双壁空心管受弯承载力理论计算式。结果表明:该种双壁空心管受弯时,受拉区的FRP管环向受压、受压区的FRP管环向受拉,跨中挠度达到跨度的1/24时承载力尚未下降。在试验、数值计算和理论计算结果的基础上,提出了该种双壁空心管受弯承载力简化计算式,建立了以弯曲刚度表示的该种双壁空心管截面弯矩-曲率关系三折线模型。

Moment-curvature relationships of FRP-concrete-steel double-skin tubular members

Tests were conducted on 3 specimens to study the flexural behavior of fiber reinforced polymer(FRP)-concrete-steel double-skin tubular members(DSTMs).The strip method was used to calculate the section moment-curvature curves for the 3 specimens and 12 different models.A theoretical formula is presented for the flexural strength of DSTMs.The test results show that the tension zone of the specimen FRP tubes was in hoop compression while the compression zone was in hoop tension.The load-carrying capacity did not decrease even when the midspan deflection reached about 1/24 of the span length.The tests,simulations,and theoretical analysis resulted in a simplified formula for the flexural strength of DSTMs and a tri-linear moment-curvature model expressed as a function of the section bending stiffness for DSTMs.