The application of pure basalt fiber (BFRP) in high-stress environments is often limited by its insufficient tensile and shear strength. To address this challenge, this study developed a novel carbon/basalt fiber hybrid composite anchor (BFRP/CF-CAR) by incorporating carbon fibers into a basalt matrix. Specifically, specimens with carbon fiber volume fractions of 8
Bio-inspired helicoidal composite (BIHC) materials are advanced artificial composites that draw on the principles of nature’s living organisms to achieve fiber-reinforced orientations. These materials can be used in aerospace components, impact-resistant structures, and advanced armor, thereby eliminating concentration at interfaces in laminated composites. Because BIHC materials are layer-wise composites, using a refined zigzag theory (RZT) to predict the static and dynamic behavior of Bio-inspired helicoidal composite (BIHC) beams is more appropriate than using any equivalent single-layer theories. Hamilton’s principle is used to derive governing equations, which are solved analytically to obtain static and dynamic results. Additionally, Duhamel’s integral, or convolution integral, is used to determine the dynamic response of the beams under various types of dynamic loading. The proposed models can provide exact solutions for the static and dynamic responses of BIHC beams, serving as benchmarks for validation in future studies. The results demonstrate that the degree of the zigzag phenomenon in the beams is affected by shear stiffness components and increases when there is a significant difference in shear modulus between the planes. Based on this investigation, it is found that beams with quasi-isotropic (QI) lamination have lower capacity to resist deformation compared to other angle orientations. The beams can be strongest when made from Fibonacci-helicoidal lamination (FH). When designing BIHC beams, other influences, such as lay-up architecture, loading types, beam slenderness, material properties, etc., that have a considerable impact on the structural behavior of the beams must be taken into consideration, which are already revealed in this study.
Quasi-static and fatigue three-point end-notched flexure (3-ENF) tests are respectively conducted on hybrid plain-woven carbon/glass fibre reinforced polymer (FRP) laminate to determine fracture toughness and propagation resistance of mode II interlaminar delamination, and delamination propagation mechanism and failure mode are thus analyzed and discussed from experimental observation. Based on bilinear traction-separation constitutive model and strain energy release rate concept, new progressive delamination propagation model and algorithm are devised to simulate mode II interlaminar delamination propagation progression under quasi-static and fatigue 3‑ENF loading. Simulations agree well with experiments, manifesting the effective usage of new model. New model proposed opens an avenue for evaluating delamination resistance of hybrid plain-woven FRP laminate in engineering design.
As modern industries’ concern shifts toward lightweight and high-performance composite materials, their reliability has become the base stone for the next generation in aerospace and automotive engineering. The transition from mechanical joints to adhesive bonding in composite structures represents an essential development in structural design. Understanding the mechanical behavior at the bonding interface has become a necessity to ensure the long-term performance. Adhesive bonding offers numerous advantages over mechanical fastening, such as higher fatigue resistance, where no stress concentrations are introduced, which come with fasteners. However, it is crucial to render the adhesives much stronger than in their conventional state. This study aims to enhance the lap shear strength of epoxy-based adhesive single lap joints (SLJs). For this purpose, inorganic micro-particles of borax (up to 45 μm) were embedded within epoxy resin, with weight contents of up to 25
