After tunnel excavation,the surrounding rock stress redistributes and results in creep deformation phenomenon,which causes large deformation,collapse,rock burst and other disasters.In order to solve this problem,field monitoring tests of displacement and temperature of surrounding rock from 0 to 120 days were carried out to predict and evaluate the long-term stability of surrounding rock of slate tunnel.Based on the monitoring displacement and temperature change law,the improved Harris temperature time relationship expression was established and embedded into the Heard power-law creep model,so as to obtain a new improved Heard creep constitutive model considering temperature effect.The model was used to simulate the monitoring displacement of surrounding rock from 0 to 120 days verify,the feasibility,and predict the creep deformation law of surrounding rock after 500 days.The results show that:1) The stress of surrounding rock is released after tunnel excavation,and the surrounding rock is in tension state and creep accumulates;2) The displacement of surrounding rock generally shows a power-law accumulation law.The accumulation rate is fast from 0 to 60 days,and gradually slows down after 60 days.At 120 days,the displacement time history curve tends to converge,with the maximum displacement of －9.93 mm and the minimum displacement of －0.05 mm;3) The monitoring temperature of surrounding rock has an inverse proportional attenuation relationship with time,and the temperature decreases gradually with the increase of time.The improved Harris model takes temperature effect into account and can accurately reflect the relationship between rock temperature and creep time,which can provide some reference for normal operation of tunnel in later period.