Damage Evolution and Circumferential Strain Distribution Characteristics of the Bolt‐Supported Cavern under Multiple Explosion Sources

Abstract

The impact of multiple explosion sources on the safety of the underground cavern is enormous. Based on a similarity model test, the finite element software LS-DYNA3D was utilized to analyze the damage evolution and circumferential strain distribution characteristics of the bolt-supported cavern under the seven combinations of concentrated charge explosion sources in three places, including the side of the vault, side arch, and sidewall. The accuracy of the simulation results is verified by comparing them with test results. The research results indicate that the damage of the surrounding rock is mainly caused by the tensile stress wave reflected from the free surfaces and the superposition of the tensile stress wave. The damage of the surrounding rock in the cases of multiple explosion sources is not a simple superposition of that in the cases of a single explosion source. The peak circumferential stress and damage of the surrounding rock in the middle of two explosion sources are significantly greater than that of the cases of the corresponding single explosion source. In the seven cases, the peak circumferential strain of the cavern wall changes from tensile to compressive from the vault to the spandrel. When the explosion occurs on the sidewall, the peak circumferential strain of the floor is tensile.

Dynamic buckling response of buried X70 steel pipe with bolted flange connection under two-charge explosion loads

“…As far as the pipes were consented, most of the researchers concentrated their efforts on studying the dynamic performance of pipes under single-point explosion load [ [13] , [14] , [15] , [16] , [17] , [18] , 30 , 31 ]. However, multiple explosions often occur in actual terrorist attacks or industrial demolition [ 32 , 33 ]. Multiple initiation and simultaneous explosion of multiple charges could result in greater damage and loss to personnel and property due to the superposition of shock waves under certain conditions.…”