We aim to model static multi-cracking processes in concrete. The explicit dynamic relaxation (DR) method, which gives the solutions of non-linear static problems on the basis of the steady- state conditions of a critically damped explicit transient solution, is chosen…
We aim to model static multi-cracking processes in concrete. The explicit dynamic relaxation (DR) method, which gives the solutions of non-linear static problems on the basis of the steady- state conditions of a critically damped explicit transient solution, is chosen to deal with the present high geometric and material non-linearities. One of the common difficulties of DR method is its slow convergence rate when non-monotonic spectral response is involved. A modified concept that is distinct from the standard DR method is introduced to tackle this problem. The methodology is validated against the three point bending test on notched concrete beams of different size, the solutions along the whole load-displacement curve, specially the peak load, the post-peak behavior follow closely after the experiments results; the size effect is caught naturally as a result of the calculation, micro cracking and non-uniform crack propagation across the fracture surface also come out directly from the 3D simulations.