Mechanically tunable bamboo sliver winding composites (BSWC): A bending stress control strategy

Bamboo sliver winding composites (BSWC) are emerging as a sustainable alternative to traditional winding composites, yet the limited understanding of their mechanical tunability has hindered the design of diversified products. Here, we introduced a bending stress control strategy to achieve controllable mechanical properties in BSWC. Bending stress arose from the combined effects of sliver thickness, elastic modulus, fiber volume fraction (FVF), and fiber volume fraction gradient (FVG). At high FVFs, both the hoop tensile strength and interlaminar shear strength of BSWC followed a quadratic relationship with bending stress, with maximum values of 128.70 MPa·cm³ /g and 12.01 MPa, respectively—significantly exceeding those of conventional bamboo or natural fiber winding composites and surpassing the ISO 18776:2008 standard. Feature importance analysis revealed that five parameters—bending stress, elastic modulus, FVG, FVF, and thickness—were sufficient to predict BSWC's mechanical properties, with bending stress exerting the most decisive influence. This work provided a clear mechanistic pathway for regulating the mechanical performance of BSWC, enabling optimal winding states and expanding their application in diversified and sustainable engineering materials. • A bending stress control strategy for tunable mechanical properties in BSWC was proposed. • The hoop prestress characteristic of BSWC was investigated. • The hoop tensile and interlaminar shear performance of BSWC were studied. • The controllable mechanisms of mechanical properties in BSWC were deeply analyzed.