Stiffened structure-induced gain-phase errors degrade the performance of the high-resolution two-dimensional multiple signal classification (2D-MUSIC) algorithm, which makes it impossible to ensure ...the high accuracy of impact localization results. To eliminate the localization bias caused by these errors, a calibrated 2D-MUSIC-based impact localization method is first introduced. Firstly, time-frequency characteristics of the non-stationary impact signals are evaluated by experiment to obtain a clear first wave packet or a wave packet that purely corresponds to a single mode through continuous wavelet transform (CWT). Then, the uniform linear array covariance matrix with gain-phase errors is calibrated to be constructed as a Toeplitz structural matrix. By reconstructing covariance matrix R, 2D-MUSIC-based impact localization is calibrated for stiffened curved composite structures. Experimental research on the stiffened curved composite panel is carried out, and these impact localization results demonstrate the validity and effectiveness of the calibrated 2D-MUSIC-based method.
In bridge construction, the use of stiffened plates for box-girder or steel beams is common day to day practice. The advantages of the stiffening from the economical and mechanical points of view are ...unanimously recognized. For curved steel panels, however, applications are more recent and the literature on their mechanical behaviour including the influence of stiffeners is therefore limited. Their design with commercial finite element software is significantly time-consuming, which reduces the number of parameters which can be investigated in an optimization procedure. The present paper is thus dedicated to the study of the behaviour of stiffened curved panels under uniform longitudinal compression. It addresses the linear buckling and the ultimate strength which are both influenced by the coupled effects of curvature and stiffening. It finally proposes a design methodology based on that for stiffened flat plates adopted by European Standards and a column-like behaviour.
•Interaction between curvature and stiffening on the shape of the buckling modes.•Reliability of EC3 model for flat panels for reduced curvature of sub-panels.•New design procedure based on a column-like behaviour for high curvatures.
An experimental and numerical study on the buckling and post-buckling behaviors of hat-stringer-stiffened composite curved panel under axial compression load was carried out. Several influence ...factors, such as skin thickness, panel radius, and distance between two adjacent stringers were studied. Three groups of stiffened curved panel buckling and postbuckling behaviors were obtained. An engineering approach was proposed to predict the initial buckling load of curved panel. Finite element analysis was used to investigate these tests and the FE models were performed by ABAQUS. The experiment results compared with that of numerical are presented. The capability and feasibility of numerical predictions in post-buckling field was assessed by comparing with experimental data. Good agreement between experimental and numerical results was observed.
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