Abstract
Skin crack defects can develop in sandwich honeycomb composite structures during service life due to static and impact loads. In this study, the fracture behavior of sandwich honeycomb composite (SHC) beams containing crack at the skin was investigated experimentally and numerically under four-point loading. Three different arrangements of unidirectional (UD) carbon fiber composite and the triaxially woven (TW) fabric were considered for the skins. The presence of a 10 mm crack at mid-span of the top skin, mid-span of the bottom skin, and mid-way between load and support of the top skin, respectively, were considered. Failure load equations of the load initiating the skin crack extension were analytically derived and then numerically developed using the J-integral approach. The crack extension failure mode dominated all cracked specimens except those with low-stiffness skin which were controlled by the compressive skin debonding and core shear failures.
Highlights
Composite sandwich structures are highly suitable for applications as structural components that require low-mass and flexibly, such as in aerospace, marine, and civil engineering fields [1]
The UD0/90, TW0/UD0, and TW0/UD90 sandwich honeycomb composite (SHC) beam specimens were investigated in the presence of pre-existing compression crack, TC, tension crack, BC, and shear crack, SC
The experimental results showed that the flexural-compression SHC beam specimen failed in a brittle manner in terms of compressive skin failure resulted from the extension of the compression crack
Summary
Composite sandwich structures are highly suitable for applications as structural components that require low-mass and flexibly, such as in aerospace, marine, and civil engineering fields [1]. The composite sandwich structure consists of two thin but stiff composite skins separated by a light-weight core [2]. With the increasing use of composites sandwich structures in primary load-bearing structures, there is an appreciable rise in interest in the influence of defects on their mechanical properties. Defects can develop during the service life of composite sandwich structures by static, impact or fatigue loading [4]. The strength of the sandwich structure is a result of the combination of the properties of the face skins, core, and interface. The defects of sandwich structures as a result of fabrication, assembly or during service phase can be commonly found in the forms of skin core debonding, crack at the core, and crack at the skins.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
