Buried Pipeline Explosion Damage Effect On Concrete Roads

Buried pressure pipeline’s explosion may result in serious life and property losses. The study of damage effect induced by pipeline explosion has important meaning for the risk evaluation of underground utilities and the establishment of security protection code. In this paper the damage effect of the cement concrete road caused by buried explosion was simulated with the SPH (Smoothed Particle Hydrodynamics) and SPH-Lagrange coupled algorithm. The study results are as follows:(1) The formation of blasting crater and the transition laws of stress wave in multi-layer media under the cement concrete pavement by the explosion are simulated. The cumulative damage graphic, speed history curves and pressure history curves are obtained. The simulating results were compared with the experiment results in literature to verify the feasibility of the algorithm and the trusts of the calculation results.(2) The explosion in the pipe was simulated and the influence of the pipe on the explosive shock wave propagation was analyzed. The results show that the pipe wall enhanced internal shock wave pressure, but on the other hand, the bursting of the pipe consumes the explosion energy simultaneously. Whether the shock wave effect increases or decreases on the surround media outside the pipe is depended on the thickness of the pipe wall, the charge equivalent and other factors.(3) The damage pattern of the cement concrete road induced by the inner explosion of the pipe was simulated. The sandy soil around the pipe forms a tapered shape along the pipe axis. The shape of the damage of the concrete pavement is the "spindle shape" and the damage area developed annularly before concrete broken. From the cumulative damage graphic, speed history curves and pressure history curves, it can be seen that the initial broken point is at the location opposite to the first broken sides in pipe, rather than at that nearest to the detonation center.(4) The damage effect of the cement concrete road induced by the inner explosion of the pipes in different buried depth was simulated. When shallow buried, pipe explosion will cause a heavy damage to the cement concrete pavement along the pipe with axial. The pressure peak values of the observation points on the concrete pavement present the trend of "small-big-small-big-zero" with the buried depth, reflecting that if buried depth is deep enough, the damage level of cement concrete pavement will be weakness.