During the blasting engineering of manual hole digging piles, due to the hardness of rocks and complexity of surrounding buildings, the rock size is large and the blasting depth is low for ordinary blasting, which severely affects the engineering progress. To solve the above problem, this study puts forwards the symmetric bilinear initiating technique to improve the energy utilization rate of explosives based on the relevant literature of matching criteria between explosives and rocks. Firstly, the fluid-solid coupling algorithm in finite element software LS-DYNA3d is applied, to conduct numerical calculation for the detonation wave propagation and rock cracking process in the center detonator initiating and symmetric bilinear initiating, respectively. It is observed that the maximum blasting pressure of the center line under symmetric bilinear initiating technique is 13.5GPa, which is at least twice of that under central detonator initiating. Besides, the rocks under symmetric bilinear initiating technique firstly break in large diameter in the central line and then expand outwards; while rocks under central detonator initiating expand around in the direction perpendicular to blasting hole. Finally, production and application of symmetric bilinear initiating cartridge in pile blasting. The results shows that the blasting footage can increase 166.67% when using the symmetric bilinear initiating technique, the rock fragmentation is low, no need secondary crushing. This study can provide a good reference for the improvement of hard rock blasting in civil engineering.