Strain-based assessment of nominally high-frequency blast induced vibrations in a near-field masonry housing structure

Blast-induced ground vibrations are typically evaluated using Peak Particle Velocity (PPV) and frequency-band criteria; however, these descriptors provide only an indirect indication of the stress demand experienced by structures. This study investigates the dynamic coupling between ground vibrations and structural stress response using an integrated vibration–strain monitoring approach applied to a masonry building located in the near field of an operating open-pit dolomite mine. Ground motions were recorded using triaxial geophones and combined with surface strain measurements on a load-bearing wall, enabling reconstruction of three-dimensional dynamic stress states within the structure. Signal interpretation employed one-third-octave analysis, Matching Pursuit time-frequency-energy decomposition, and response spectrum analysis. Free-field vibration records were dominated by spectral components in the 30–100 Hz range and would conventionally be classified as high-frequency blasting vibrations. However, structural measurements revealed strong attenuation of higher-frequency components and redistribution of vibrational energy during transmission through the soil-foundation-structure system. Reconstructed stresses showed clear linear relationships with PPV in all directions, with the vertical component exhibiting the strongest correlation (R 2 ≈ 0.92) and tensile stresses dominating the stress field. Time-frequency analysis demonstrated energetic synchronisation between vibration velocity and structural stress signals. Response spectrum analysis further revealed that, despite the high-frequency character of the input motion, the dominant structural response occurred at vibration periods of approximately 1 s, corresponding to low-frequency structural modes. These findings demonstrate that vibrations operationally classified as high-frequency may still produce low-frequency structural response governed by structural dynamics. The proposed vibration-strain-energyresponse framework provides a physically consistent basis for linking blasting parameters with structural stress demand and supports improved vibration safety assessment in near-field mining environments. • Integrated geophone-strain monitoring quantified stress transfer from blast vibrations • Linear PPV-stress relations identified in all three orthogonal directions • Matching Pursuit revealed full energy synchronisation of vibration and stress • Response spectra show low-frequency structural demand from high-frequency blasts • Results support stress- and energy-based vibration safety assessment in mining