Buckling and forming processes of tubes with varying slenderness ratio （ratio of length to diameter） under external hydraulic pressure were analyzed with three-dimensional finite element method （FEM） for studying ...Buckling and forming processes of tubes with varying slenderness ratio （ratio of length to diameter） under external hydraulic pressure were analyzed with three-dimensional finite element method （FEM） for studying tube external pressure forming （EPF）. Buckling pressures for different tube blanks without mandrel were predicted, and an EPF of a carbon steel tube onto a mandrel with six ribs was simulated. Both thickness distribution and buckling pressure from the simulations were found to be in agreement with those from experiments. Buckling pressures are shown to be a function of the slenderness ratio. The tubular part with six ribs produced by EPF has a uniform thickness distribution, whose maximum thinning rate is only 5.9%.展开更多
为了检测钢筋混凝土排水管质量,采用外压荷载试验,通过荷载-应变曲线对2根钢筋混凝土排水管的裂缝荷载以及在各级荷载作用下的局部变形进行分析。测试结果表明,各测试面均出现不同程度的局部变形和裂缝。顶部为荷载集中区域,应变较大;...为了检测钢筋混凝土排水管质量,采用外压荷载试验,通过荷载-应变曲线对2根钢筋混凝土排水管的裂缝荷载以及在各级荷载作用下的局部变形进行分析。测试结果表明,各测试面均出现不同程度的局部变形和裂缝。顶部为荷载集中区域,应变较大;两侧裂缝多居于管外壁,内壁较少。1号管裂缝荷载值为325 k N/m,2号管裂缝荷载值为324 k N/m。相同荷载下,1号管比2号管表现出更好的延展性能,具有更高的承载能力。2根钢筋混凝土排水管均满足GB/T 11836—2009《混凝土和钢筋混凝土排水管》Ⅲ级管裂缝荷载标准。展开更多
基金The authors would like to thank the Scientific Research Fund of Harbin Institute of Technology （Grant No. HIT.2002.33） the National Natural Science Foundation of China （Grant No. 59975021） for financial support of this research.
文摘Buckling and forming processes of tubes with varying slenderness ratio （ratio of length to diameter） under external hydraulic pressure were analyzed with three-dimensional finite element method （FEM） for studying tube external pressure forming （EPF）. Buckling pressures for different tube blanks without mandrel were predicted, and an EPF of a carbon steel tube onto a mandrel with six ribs was simulated. Both thickness distribution and buckling pressure from the simulations were found to be in agreement with those from experiments. Buckling pressures are shown to be a function of the slenderness ratio. The tubular part with six ribs produced by EPF has a uniform thickness distribution, whose maximum thinning rate is only 5.9%.
文摘为了检测钢筋混凝土排水管质量,采用外压荷载试验,通过荷载-应变曲线对2根钢筋混凝土排水管的裂缝荷载以及在各级荷载作用下的局部变形进行分析。测试结果表明,各测试面均出现不同程度的局部变形和裂缝。顶部为荷载集中区域,应变较大;两侧裂缝多居于管外壁,内壁较少。1号管裂缝荷载值为325 k N/m,2号管裂缝荷载值为324 k N/m。相同荷载下,1号管比2号管表现出更好的延展性能,具有更高的承载能力。2根钢筋混凝土排水管均满足GB/T 11836—2009《混凝土和钢筋混凝土排水管》Ⅲ级管裂缝荷载标准。
