为研究长桁-蒙皮界面初始脱粘缺陷对复合材料加筋板压缩力学性能的影响，开展了试验和仿真分析研究。首先，通过数字图像相关技术（DIC）和电阻应变计测试了加筋板的屈曲及后屈曲行为，结果表明：初始脱粘缺陷对结构屈曲载荷影响较小，但会使得加筋板压缩过程中发生屈曲模态转换，初始脱粘区域附近界面提前破坏，导致结构承载能力显著降低（降幅达18.6%）。随后，采用考虑面外压缩应力抑制剪切失效的界面失效准则提出了一种基于组合本构的界面模拟新方法：采用Cohesive单元同时模拟完好界面（双线性损伤本构模型）和初始脱粘界面（接触本构模型）。在此基础上建立了复合材料加筋板渐进损伤有限元模型，分析了结构的后屈曲失效过程。数值模拟结果与试验数据高度吻合：屈曲载荷预测误差小于4%，破坏载荷误差小于7%，且准确再现了屈曲模态转换和失效演化过程。最后，通过参数化分析探讨了脱粘缺陷尺寸和位置对加筋板压缩屈曲与后屈曲性能的影响规律。研究成果可为复合材料加筋结构的损伤容限设计提供参考。

This study combines experimental and numerical approaches to investigate the effects of initial debonding defects at the stringer-skin interface on the compressive behavior of composite stiffened panels. Digital Image Correlation （DIC） and strain gauge measurements were employed to characterize the buckling and post-buckling behavior. The experimental results demonstrate that while the initial debonding has limited influence on the buckling load， it induces buckling mode transition during compression and causes premature interfacial failure near the pre-existing debonded region， leading to a significant reduction （up to 18.6%） in structural load-bearing capacity. An innovative cohesive zone modeling approach was developed based on an interface failure criterion that accounts for the inhibition of shear failure due to out-of-plane compressive stress， where the intact interface and pre-debonded region were simulated using cohesive elements with a bilinear damage constitutive model and contact constitutive model， respectively. A progressive damage finite element model was subsequently established， successfully reproducing the post-buckling failure process. The numerical predictions show excellent agreement with experimental data， with buckling load errors below 4% and failure load errors within 7%， while accurately capturing the buckling modes transition and failure progression. Parametric studies were conducted to evaluate the effects of debonding size and location on the compressive post-buckling performance. The findings provide valuable references for damage-tolerant design of composite stiffened structures.