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The propagation and attenuation characteristics of blast stress waves in geotechnical media directly influence the fracture behavior of the medium and serve as a crucial basis for optimizing blasting parameter design. To examine the attenuation characteristics of cylindrical blast waves in rocks, the indoor blasting experiments were conducted using sandstone with cylindrical charges. Digital image correlation technology was employed to successfully capture the full-field strain evolution around the borehole during blasting, and the strain–time curves of the rock surrounding the borehole were obtained. To account for the influence of blasting stress wave loading rates on dynamic elastic modulus, Split Hopkinson Pressure Bar tests were performed to establish a precise relationship between dynamic elastic modulus and strain rate. By analyzing the attenuation of the peak strain, a stress wave attenuation equation within the fractured zone was developed, and the stress wave attenuation index was examined. The results indicated that the experimental method effectively simulated the blasting process of cylindrical charges. The strain wave propagation was accompanied by energy transformation, where the descending phase of the strain–time curve represented the rapid energy input to the rock near the borehole due to blast loading, whereas the ascending phase reflected the radial release of elastic energy, further promoting the development of circumferential cracks, albeit at a lower energy release rate than the descending phase. As the distance from the blast center increased, both the dynamic elastic modulus and strain rate of the rock under blast loading decreased, leading to differences between the attenuation characteristics of stress waves and strain waves, with the former following a power function decay. The complex nature of stress wave attenuation in rocks was primarily governed by physical attenuation properties, with the physical attenuation index exceeding the geometric attenuation index in crushed and cracked zones. Finally, the accuracy of the stress wave attenuation equation and the reliability of the experimental method were validated by analyzing the fracture morphology of the blasted specimens and the extent of the cracked zone.

In Morocco, urban expansion is driving a high demand for construction materials, intensifying mining operations through explosive blasting. These blasts produce seismic and acoustic vibrations that can damage buildings and harm the health of nearby residents. Current mitigation methods are often ineffective, costly, or poorly adapted. This work proposes an innovative solution based on metamaterials, capable of attenuating the propagation of harmful vibrations within specific frequency ranges (< 50 Hz). The approach includes : field vibration measurement campaigns, laboratory geotechnical testing, and numerical simulations to evaluate the effectiveness of metamaterials compared to conventional solutions. The objective is to develop robust, economical, and adapted devices for Moroccan conditions to better control the vibrational nuisances from mining blasts.

The evaluation of the seismic action generated by blasting, aims to establish the connection between the levels of ground vibration with the parameters of the blasting and the characteristics of the geological environment related to the quarry. In order to assess the seismic effects on site of the mining / civil / industrial objectives within the quarry, the criterion of the oscillation speed of the soil particles was chosen, because it was considered to be the only reproducible parameter for the whole frequency range of earthquakes which depends to a lesser extent on rock properties. Blasting works, especially large-scale ones, with significant amounts of explosives, produce a considerable seismic effect that can be felt in areas more or less closed to the site of the works. The sizing of the charges used both on the delay stage and on the hole, is a concern that must be taken into account when designing the applied blasting technology. The oversizing of the loads that are fired, according to the technology proposed by the framework operating plan, can lead to damage to the structure of civil or industrial buildings, infrastructure elements such as power lines, gas or water pipes, roads and railways. Applied research carried out by INSEMEX specialists over time, through research and development contracts, has led to certified technical solutions, based on field measurements, agreed by all parties involved).