A key aspect of urban blasting engineering is evaluating the safety of the blasting dynamic load on the adjacent high-density polyethylene water supply pipeline and controlling the negative impact of the blasting vibration load on the pipeline. According to the special characteristics of the soil layer in Shenzhen coastal city, a field blasting test of a full-scale pre-buried HDPE pipeline was carried out, and the distribution characteristics of the blasting vibration velocity and dynamic strain were analyzed. The finite element model was established by LSDYNA, and the reliability of the calculation model and parameters was verified by comparing with the field test data. At the same time, the dynamic response characteristics of pipelines with different buried depths, operating water conveyance pressures, and diameters under blasting vibration loads were studied. Combined with the circumferential allowable stress control criterion of the pipeline, the safety control standard of the blasting vibration velocity of the HDPE water supply pipeline under different working conditions was proposed. The results show that the circumferential compressive strain of the HDPE pipe is the most affected by blasting vibration, and the pipe with the shortest blasting center distance has the largest response. The vibration velocity and equivalent stress of the pipeline increase with the increase of buried depth, internal pressure, and diameter. The vibration velocity and equivalent stress of the explosion side at the same section of the pipeline are greater than those of the back explosion side. Based on the dimensionless analysis, the vibration velocity prediction model of the buried depth, operating pressure, and diameter of the pipeline is proposed. The safety control velocity of the pipeline is 25 cm/s, and the vibration velocity of the upper surface is 22.5 cm/s according to the Mises yield strength criterion.

As one of the types of trenchless excavation, pipe-jacking tunnel is being popularly adopted in the fields of municipal pipeline projects and others'. However, it is rare that the technology of pipe-jacking tunnel is used in petroleum and gas transmission engineering. Taking Sheshui River Pipe-jacking Tunnel that is part of Second West-East Gas Transmission Pipeline Project as example, the Plaxis 3D finite element software was utilized to analyze the stress distribution around the tunnel and settlement features after excavation, which would be useful to guide the safety control of construction. The results showed that the lining structures of pipe sections can generally meet the needs of construction in three different buried depths (13m, 18m and 20m), but the maximum settlement displacement would reach to 1.5–2.0 cm even 2.5 cm in some simulation zones, which called for the enhancement of settlement monitoring.