Abstract:Dieterich physics-based approach build up a seismic rate forecasting model based on rate- and state-dependent friction law. According to previous research,we modeled the aftershock rate of the Qianguo seismic swarm in 2013 based on the R-S model. We considered coseismic Coulomb stress changes to be the initial stress perturbation. And,based on logarithm maximum likelihood best fit method,we present two different fitting mode. One is a fitting considering fixed aftershock duration fixed ta. Another is considering a non-fixed aftershock duration non-fixed ta. We found,fixed ta mode provide a faster procedure calculation and a more correct parameter fitting results,while non-fixed ta mode provide a larger lnL and a smaller AIC value. Finally,we consider the aftershock rate forecasting of the Qianguo seismic swarm based on the fixed ta mode. The forecasted aftershock number per day has a well positive correlation with observation. The stress shadow near the mainshock failure leads to a lower forecasted value compared with observation,which means more other trigger mechanisms for aftershock activity.