In order to study the blasting technology of the in-situ collapse of a cooling tower, the incision was analyzed by finite element software. Furthermore, a high-definition camera was used to collect the deformation data of the cylinder body and lambdoid stand columns. Then detailed analysis was carried out for the deformation time of the cylinder, the collapse speed, the change of the incision closure, and the collapse range after the distortion and deformation of the cylinder. The practice results show that the incisions for the in-situ collapse of the cooling tower cannot be designed as four equal parts as convention. It is easy for four equally distributed parts to cause the bottom part not to collapse. The perimeter of the fourth area (the last initiated part) is slightly larger than that of the first area by a quarter. The in-hole delay times in the four areas are MS4, MS8, MS8 and HS3, respectively, and the out-hole delay time is MS2. Through the finite element simulation, it takes 1 second to generate the collapse trend of the cylinder, 3 seconds to close the incisions of the cylinder, and 6.8 s for the cylinder to squeeze, twist in the air and touch the ground. The deformation of each area must be completed within a reasonable time. By image analysis and calculation after the explosion, the above simulated times are the same as the actual times.90% of the in-situ collapsed cylinder is within the pool, and the upper ring beam is thrown out of the pool by about 6 meters, which does not affect the surrounding hydrogen production station, circulating water pump room, steel gate and other facilities. After measurement, the peak vibration velocity the natural gas pipe is only 2.095 cm/s, indicating no impact on the buried gas pipe 23 meters away. The research shows that the in-situ collapse blasting technology can effectively control the collapse touch-down vibrations and the collapse throw distance of the cylinder.

In order to analyze the dynamic response of the shield segments during the blasting excavation of a connecting channel, on-site vibration monitoring has been conducted based on the shield interval project of Qingdao Metro Line 8. The measured blasting vibration data show that the cut holes have the strongest impact on the shield segment vibrations. Then, based on the on-site charge of the cut holes, the MIDAS-GTS NX simulation software is used to establish a three-dimensional model to analyze the vibrations and stresses of the shield segments with 8 different blasting distances from the exit and entry of the connecting channel. Compared with the entry blasting, the impact of the exit blasting on the vibrations of the adjacent shield tunnel is more intense under the same blasting distance, and the peak vibration velocity is 2.9~3.4 times that of the entry blasting. On the other hand, the growing rate of the peak vibration velocity also increases with the decrease of the distance. When the allowable vibration velocity is 20 cm·s^-1, the blasting distance should be greater than 5.0 m at the exit and greater than 1.25 m at the entry. The rocks that have not been excavated are excavated with non-blasting methods. The stress concentration is the most obvious in the opening segments, but the position where the maximum principal stress is generated shifts from the bottom of the rectangular opening through the intersection of transverse and longitudinal seams on the side of the rectangular opening to the top corners of both sides of the upper part of the rectangular opening with the decrease of spacing. Cutting the segments at the intersection of the connecting channel and the shield tunnel will form an incomplete opening structure, which will weaken the maximum principal stress on its inner side under the blasting load, but will cause a small range of stress concentration on its outer side, making it the weakest position of the shield tunnel lining structure.

As a discontinuous and anisotropic heterogeneous structure, rock mass is randomly distributed with joints, cracks, faults and other structural planes. The existence of structural planes has an important influence on blasting effect. In order to explore the influence of the angles and locations of structural planes on bench blasting effect, LS-Dyna numerical simulation and field experiments were conducted based on Beskuduk open pit coal mine. The numerical simulation results show that when the dip of the structural plane is less than 30 degrees, the peak stress is less affected. When the dip of the structural plane is greater than 30 degrees, the initial peak value of the explosion stress wave increases with the increase of the angle. In addition, the position of a weak interlayer in a bench affects the energy release. Compared to the situation that the weak interlayers are located in the upper area of the bench, the blasting effect when the weak interlayers are located in the middle and lower areas, the energy release is more obvious with a worse blasting effect, therefore a specific blast method is needed to solve the problem. The field practice shows that with the increase of the structural plane angle, the boulder yield presents a decreasing trend. For the situation that the weak interlayers are located in the middle and lower part of the bench, the method of increasing the subdrilling to 0.5 m and adding 3~5 m depth to the inclined holes can effectively reduce the boulder yield, improve the blasting effect and the shovel loading efficiency.