Research on Controlled Blasting Demolition Technology for Two Adjacent Boiler Rooms in a Densely Built Environment

Aiming at the blasting demolition of two adjacent boiler houses with reinforced concrete-steel composite frames in a power plant, systematic analysis was conducted on their structural characteristics and surrounding environmental conditions.analysis reveals significant structural vulnerabilities, including strong coupling effects, imbalanced aspect ratios, and risks of center-of-gravity deviation, compounded by complex site conditions and strict safety requirements for demolition operations. To address these engineering challenges, the research employed rigid-body center-of-gravity synthesis theory to segment structural mass units and precisely calculate the boiler houses′ center of gravity at approximately 36 meters in height. By integrating the collapse geometric model of coupled frame structures with empirical engineering formulas, critical blasting cut parameters were determined. Following the weak-column-strong-beam design principle, the blasting parameters of RC columns were optimized. Artificial pre-cutting technology severed hidden load-transfer paths between the two buildings, ensuring synchronous destabilization of the RC and steel structural systems. Additionally, increasing inter-row delay time (2nd to 3rd columns) to 1 second facilitated supporting-point forward displacement, effectively preventing boiler house structural arrest due to insufficient aspect ratios. A 2~3 second delay interval was implemented between the two boiler houses to prevent superposition of vibration energy, while an integrated protective system was employed to mitigate blasting-induced hazards. Field tests confirmed both structures collapsed precisely along predetermined trajectories with compact debris piles and complete structural fragmentation. Measured blasting and collapse vibration velocities remained below safety thresholds, with no incidents of flying rock or adjacent structure damage. These results successfully address critical technical challenges in the demolition of multi-boiler houses in dense environments, establishing reliable engineering references for comparable projects.