【摘要】 本文针对初始形状缺陷对薄壁钛合金环肋圆柱壳结构极限承载及失效模式的影响问题，结合径厚比、长径比和肋距等参数，开展了结构设计计算、极限承载及失效模式研究，并进行了试验验证。设计并加工含初始形状缺陷的焊接模型和无形状缺陷的精车模型；通过理论公式推导与数值仿真，分别获得两个模型典型部位的结构应力和模型临界失稳压力；进而开展了模型静水外压试验，考核其结构强度与极限承载能力，得到两个模型应力分布特征、破坏压力及破坏形态。通过对比理论、数值和试验结果，系统分析了初始形状缺陷对结构强度和极限承载能力的影响，为薄壁钛合金环肋圆柱壳结构的设计、计算和评估提供研究依据。更多还原

【Abstract】 This paper investigates the influence of initial geometric defects on the ultimate load capacity and failure mode of thin-walled titanium alloy ring-ribbed cylindrical shells. The study combines key geometric parameters, including the radius-to-thickness ratio(R/t), length-to-radius ratio(L/R), and rib spacing(u), to conduct structural design calculations and analyze failure modes, supported by experimental verification. A welded model(with initial defects) and a precision-machined model(without defects) were designed and fabricated. Theoretical analysis and numerical simulations were performed to obtain the structural stress distribution and critical buckling pressure at critical locations on both models. Subsequently, hydrostatic external pressure tests were conducted to evaluate the structural strength and ultimate load capacity, revealing the stress distribution characteristics, failure pressure, and failure modes of each model. By comparing the theoretical, numerical, and experimental results, the impact of initial shape defects on structural performance was assessed. This comparison provides a robust basis for the design, calculation, and evaluation of thinwalled titanium alloy ring-ribbed cylindrical shell structures.更多还原