The stress wave induced by CO2 phase transition can be used to generate rock fractures.It is important to investigate the propagation and influence law of this stress wave.Based on the self-developed triaxial strain testing device,a testing scheme was designed by utilizing a dynamic strain measurement system to collect strain signals during CO2 phase transition and rock fracturing.The research results indicate that the peak stress in the jet direction and perpendicular to the jet direction decays exponentially with the increase of propagation distance,and the peak stress in the jet direction is significantly greater than that perpendicular to the jet direction.CO2 filling amount and shear sheet thickness are important factors affecting the peak stress for CO2 phase transition fracturing.When the shear sheet thickness is constant,the peak stress increases with the increase of CO2 filling amount,but the increasing rate decreases gradually.Similarly,while the CO2 filling amount is constant,the peak stress increases with the increase of shear sheet thickness,showing a continuous growth trend.