An incremental inverse analysis procedure for identification of bond-slip laws in composites applied to textile reinforced concrete

Textile reinforced concrete (TRC) is a novel composite building material, its structural behavior is substantially influenced by the bond interface between the reinforcing textile fabrics and concrete. The bond interface can be characterized by a nonlinear bond-slip law. The pull-out test is a common experimental procedure for determination of the bond-slip law. In this paper, a general finite element procedure is proposed to calibrate the bond-slip law according to the results of pull-out tests. By adopting a generic multilinear bond-slip law and solving each piece of the law sequentially, the conventional curve fitting procedures employing optimization algorithms, which are computationally expensive and sometimes non-convergent, can be avoided. Pull-out tests of TRC specimens with varying anchorage lengths were carried out and the test results were used as the input data for the calibration procedure. It is found that the calibrated bond-slip law is independent of the specimen length. Using the calibrated bond-slip laws, the pull-out force vs. displacement curves are numerically reproduced. The numerical results agree well with the experimental data.