Abstract: At present,wet shotcrete is gradually replacing dry shotcrete,but the relevant supporting mechanism and design basis are lack of research. According to the mechanics tests of dry and wet shotcrete,the acoustic emission(AE)device is used to monitor the whole process of uniaxial compression,axial compression and Brazilian splitting instability in order to explore the mechanical properties and failure mechanism of wet sprayed concrete. The acoustic emission energy and impact number of the whole failure process of the sample,as well as the time and space characteristics of the failure point of the sample are obtained. Based on the test results,the failure mechanisms of dry and wet shotcrete are explored,and the uniaxial compressive strength,axial compressive strength and splitting tensile strength of dry and wet shotcrete at different ages are compared and analyzed. The relationships between the AE parameters of dry and wet shotcrete,such as stress,impact number,energy and strain are further studied. The relationship between damage variable and strain is quantitatively analyzed through the positioning results of AE specimens. The constitutive model of damage variable of dry and wet shotcrete is established. The results show that compared with dry shotcrete,the early and long-term mechanical properties of wet shotcrete are significantly improved,and the homogeneity is also significantly improved. Damage variable expressed by AE energy increases with the increase of strain,and cracks begin to penetrate gradually under specific strains. However,the growth rate of damage variable of wet shotcrete is slow before the peak strain is reached,and fast after the peak strain is reached. By comparing the experimental and computational curves of dry and wet shotcrete,it is shown that the constitutive model can be applied to the damage comparison of crack energy of dry and wet shotcrete.