摘要
为研究剪跨比和混凝土强度对高强方钢管混凝土试件抗剪性能的影响,共设计16个高强方钢管混凝土试件.通过试验获得试件的破坏模式和剪力-位移曲线,对比剪跨比、核心混凝土强度等参数对破坏模式、剪力-位移曲线、剪力-剪应变曲线、抗剪强度和刚度的影响.研究结果表明:与普通钢管混凝土试件一致,剪跨比是控制高强方钢管混凝土试件破坏模式的主要参数,当剪跨比为0.2或0.5时,发生剪切破坏;当剪跨比为0.8或1.0时,发生弯剪破坏;采用超高性能混凝土填充高强方钢管(剪跨比为1.0),试件的变形能力降低61.4%,抗剪强度和刚度分别提高了38.9%和85.7%,且有效延缓钢管局部屈曲和降低试件的破坏程度;核心混凝土主斜裂缝产生的倾角随剪跨比增大而减小,但不受混凝土强度影响.本文抗剪强度试验值/抗剪强度计算值(V_(exp)/V_(u))的均值为0.97,方差为0.03,精度高,离散性小,认为该公式可较准确地预测高强钢管混凝土的抗剪强度.
A total of 16 concrete-filled high-strength steel tube specimens were designed to evaluate the effects of shear-to-span ratio and concrete strength on the shear behavior of concrete-filled high-strength steel tube specimens.The failure mode and shear-displacement curve of the specimens were obtained through the test,and the effects of shear-to-span ratio,core concrete strength,and other parameters on the failure mode,sheardisplacement curve,shear-shear strain curve,shear strength,and shear stiffness were compared.The results show that similar to conventional concrete-filled steel tube specimens,the shear-to-span ratio is the key parameter controlling the failure mode of the concrete-filled high-strength steel tube specimens.When the shear-to-span ratio is 0.2 or 0.5,shear failure occurs;when the shear-to-span ratio is 0.8 or 1.0,shear-flexural failure occurs.By implementing ultra-high performance concrete(UHPC),the deformation capacity of the concrete-filled highstrength steel tube specimens(with a shear-to-span ratio of 1.0)is reduced by 61.4%.However,shear strength and stiffness increase by 38.9%and 85.7%,respectively.Additionally,local buckling of the steel tubes is effectively delayed,and the damage degree of the specimens is reduced.The inclination angle of the main diagonal cracks in the core concrete decreases with an increase in the shear-to-span ratio but is not affected by the concrete strength.The average value of tested shear strength/calculated shear strength(V_(exp)/V_(u))is 0.97,with a deviation of 0.03,showing higher accuracy and smaller dispersion.It is considered that the formula can accurately predict the shear strength of concrete-filled high-strength steel tubes.
作者
王佳丽
王莹
陈西文
杨东旭
赖志超
WANG Jiali;WANG Ying;CHEN Xiwen;YANG Dongxu;LAI Zhichao(College of Civil Engineering,Fuzhou University,Fuzhou 350000,China)
出处
《西南交通大学学报》
北大核心
2025年第3期628-638,共11页
Journal of Southwest Jiaotong University
基金
国家自然科学基金项目(51978170)。
关键词
钢管混凝土
高强钢管
抗剪性能
破坏模式
设计方法
concrete-filled steel tube
high-strength steel tube
shear behavior
failure mode
design method
