Reinforced concrete structures are common forms of building structures， and the study of the damage effects of internal explosions is of great practical significance. In this study， the accuracy of the finite element modeling method for reinforced concrete structure was validated by comparing its predictions with the experimental data. Based on this method， a 2/3 scaled finite element model of a reinforced concrete shear wall structure was established to analyze the damage patterns and dynamic response of the top slab and shear wall components under two separate explosions in different rooms， as well as the cumulative damage development patterns after two successive explosions. The study reveals that： under the two separate explosions of 1kg TNT， the damage mainly occurs along the plastic hinge line of the top slab and at the connection supports of the wall and slab. The damage degree， displacement and acceleration of the top slab are significantly higher than that of the shear wall. The peak displacements at the center of the top slab in Room 2 and Room 3 reach 41.5 mm and 63.1 mm， respectively， with residual displacements of 32.2 mm and 46.1 mm. Under successive explosions in two rooms， for the slabs with lower strength and greater initial damage， the cumulative damage under the two successive internal explosions is significantly higher than the linear superposition of damages from two separate explosions. The peak displacements of the top slab center in Room 2 and Room 3 are 133.6% and 24.9% higher， and the residual displacements are 144.6% and 29.4% higher， respectively， indicating the necessity to consider cumulative damage effects. However， for the wall components with higher strength and weaker initial damage， the cumulative damage caused by the successive explosions is slightly higher than the linear superposition of damages from two separate explosions. They can be considered approximately equal， which means the cumulative damage can be neglected.