Measurements and prediction of fabric surface fitting ability under low tension.

This study investigated the surface fitting ability of woven fabric under low tension using a new measurement method. The limit angle of shear buckling, the maximum shear angle, is defined as the surface fitting ability. To estimate the maximum shear angle, we measured the base radius of a spherical crown of woven fabrics while covering the spherical surface without wrinkles. The relationship between the maximum shear angle and base radius was calculated numerically. We constructed a new testing equipment to determine the surface fitting ability of fabric with an aluminum hemisphere set on a laboratory jack and acrylic boards with holes of varying size at the center. Nineteen kinds of woven fabric samples and three hemispheres of different radii were used to measure the surface fitting ability. The relationships among the maximum shear angle and mechanical and structural properties were investigated. Thickness, interlacing point density and shear stiffness showed high correlation with the surface fitting ability. Using these properties, a new prediction formula for surface fitting ability was proposed. The predictive values showed a good agreement with the measured values. Therefore, the proposed method and the prediction equation are useful for evaluating the surface fitting ability of woven fabrics. The effect of the sphere radius on the surface fitting ability was also clarified. [ABSTRACT FROM AUTHOR]