The mathematical study of compression behaviours of silicone rubber composites reinforced by warp-knitted spacer fabrics

To synthetically investigate the compressive mechanism of warp knitted spacer fabric reinforced silicone rubber matrix composite (SRWSF) under 20% deformation, a compression meso-mechanics theoretical model was established in this paper. The silicone rubber was processed as isotropic material according to the nonlinear constitutive equation, the spacer yarn was assumed as a continuous uniform element. The compression meso-mechanics theoretical model consists of the mechanical model of silicone rubber and the compression model of warp knitted spacer fabric (WSF), based on the Euler-Bernoulli beam theory and the Spence Invariant constitutive model theory. To verify the feasibility of the compression meso-mechanics theoretical model of SRWSF, the compression test of SRWSF was carried out. The simulated compression stress-strain curve was compared with the results of the experiment. The result shows that the compression theoretical model has a high agreement with the experimental result under 20% strain, as compared with the Polynomial fitting curve. This phenomenon indicates that the compression theoretical model established in this study can reasonably simulate the actual compression behaviours within 20% deformation for SRWSF. Moreover, the theoretical model can help understand the compression mechanism of SRWSF and optimise the designing of silicone- rubber-matrix composite reinforced by WSF for cushioning applications.