Three structurally robust, high-seismic-resistance buildings in the urban core of an extremely cold, seismically active region in northwest China required demolition due to serious safety concerns. To ensure successful controlled demolition operations, comprehensive field testing of electronic detonator initiation networks at subzero temperatures was conducted, validating the firing reliability of 10000 industrial detonators and 11 initiation devices. Based on experimental findings, structural analysis, and environmental considerations, an integrated demolition plan was formulated. Building No. 3 was mechanically demolished, while Buildings No. 1 and No. 2 were concurrently demolished through controlled blasting, with Building No. 1 using a progressive span collapse blasting technique and Building No. 2 employing a unidirectional folding collapse methodology. The successful demolition resulted in the complete structural disintegration of both buildings, with outcomes exceeding performance expectations. Field implementation confirmed that for seismically reinforced core tube structures requiring controlled collapse, conducting sub-zero detonator network reliability tests, ensuring accurate delay timing, and optimizing cut design ensure precise demolition aligned with engineering specifications. The proposed method ensures optimal protection for surrounding structures, roads, and municipal pipelines while establishing an efficient and secure framework for demolishing seismically reinforced core tube buildings in frigid environments, with potential applications for comparable demolition blasting projects.