Storing petroleum in large underground caverns is an important way of strategic petroleum reserve in the world. With the increase of imported petroleum in China

constructing large underground petroleum storage caverns is no doubt a project with better comprehensive economic effect. According to the engineering characteristics of the large underground water-seal petroleum storage caverns

the excavation sequence and construction method of underground petroleum storage caverns are simulated by using numerical method. Three potential schemes of construction are analyzed and compared. Through their calculating results

including the surface settlement

the deformation of key points on the cavern boundaries

the distributive laws of the stress field and displacement field due to each excavating scheme

are studied and contrasted; the optimum construction scheme is chosen from the above schemes. The viscoelastic numerical simulation is performed for the construction process of the optimum scheme; and the deformation characteristics of petroleum storage caverns is given by considering the rheologic behaviors of rock mass. The Strength and the long-term stability of underground petroleum storage caverns are analyzed and evaluated; and the obtained conclusions have a certain referential value for the sequence of excavation and construction of underground petroleum storage cavern.