Establishment of fracture mechanics based design method for SFRC tunnel lining

点击翻译按钮获取中文摘要

The validity of the developed analysis method for crack growth in concrete is clarified by comparing numerical results with experimental data. The main concern is to check weather the localization of distributed cracks into one major crack can be reproduced or not.Uniaxial tension tests and bending tests of steel fiber reinforced concrete are conducted. The surface displacements are measured with laser speckle method, and the distribution of cracks and crack opening displacements are obtained.The transmitted stress across the crack surface is estimated through the measured crack opening displacement and tension-softening curve.The tension-softening curves obtained from uniaxial tension tests and bending tests with back analysis method are in agreement.This implies that the tension-softening curve is a material property which does not depend on the testing method.The obtained tension-softening curve is used in FEM analysis in discussions for the design method.A design method of tunnel lining with SFRC (steel fiber reinforced concrete) is proposed. The cross-sectional capacity is estimated based on fracture mechanics of concrete. To show the validity of the design method. the estimated cross-sectional capacity is compared with the existing experimental results.