Abstract
Traditional seismic excitation sources often perform poorly in complex urban settings. In this study, an innovative portable electromagnetic impact source is introduced. The design and manufacturing principles are detailed, and the performance is verified through comprehensive simulations. Furthermore, field experiments are conducted to assess the device's energy output, frequency range, and imaging accuracy in real-world engineering surveys. Experimental results show that compared with the traditional sledgehammer source, the electromagnetic impact seismic source has stronger excitation energy (the impact kinetic energy is about 1218 J, which is about 5 times that of the 24-pound sledgehammer source), and a wider frequency band (the widest range is 0.1–1200 Hz), which is critical for detection depth and accuracy. The obtained seismic data have a wider frequency band and a higher reflected wave signal-to-noise ratio, which effectively improves the resolution and detection depth of underground anomalies. The spatial distribution of air-raid shelters can be clearly identified based on the transient amplitude profile, which verifies the applicability and reliability of the electromagnetic impact source in seismic engineering surveys and demonstrates its good application prospects in the field of underground space detection. It is especially suitable for accurately detecting caves and air-raid shelters that are prone to collapse in urban road environments.