Abstract：Time integration theories applicable to the discontinuous deformation analysis(DDA) method are studied. The general formulae of the global increment displacement solution algorithm for the DDA by using Newmark method are presented. By changing the collocation parameters in Newmark method，a variety of well- known time integration algorithms are produced，including the constant，average and linear acceleration schemes. To ensure the stability of the integration algorithms，a self-adaptive damping which is in direct proportion to the imbalance force is introduced to consider energy losses for block system. An example of tunnel excavation has been analyzed，and the results are compared with those obtained by UDEC to evaluate the performance of the Newmark integration algorithms. The numerical results show the validity and the reliability of the improved DDA method.
