Precision Blasting

GeoSonics/Vibra-Tech has the monitoring technology to help you stand tall, with confidence and stability, allowing your project to tower above the competition.

Project:

Due to their close-in nature and typically high-density surroundings, construction blasting projects often require customized, site-specific seismic monitoring solutions. Considering today’s economic trends, the construction blasting company can realize considerable benefits in cost effectiveness and overall project outcome by optimizing equipment and expertise for each project.

Recently, Precision Blasting of Douglasville, Georgia was awarded a project near Atlanta that required the removal of hard, unweathered Georgia gneiss. This particular project involved mass rock blasting to remove up to 40 feet of material, followed by ditch line blasting to depths of approximately 12 feet. The project comprised phases three and four of an established town home community that was completed about two years prior. As with most projects, the established town homes were constructed in an area that required minimal blasting, leaving the less desirable “outcrop-of-rock” for future speculation. In this case, the existing town home community completely surrounded the less desirable area.

Problem:

A majority of the blasting on this project took place within a distance of 200 feet from existing structures, and in some cases, the blasting was as close as 50 feet. Due to the volume of material that needed to be removed, time constraints placed by the contractor and the community, and the persistent close proximity of blasting to structures, it was determined that numerous small blasts would be conducted each day. Due to co-existing construction activities on this project, blasts were drilled, loaded, and detonated as allowed by these activities.

Based on the anticipated number of blasts to be conducted and the random nature of blast times throughout the day, it was determined that direct seismic monitoring by an on-site technician could become cost-prohibitive to the customer.

Solution:

Considering the possible options, Precision Blasting chose to employ two totally self-contained GeoSonics/Vibra-Tech Re:mote systems at the nearest structures to the initial blasting. The solar-powered, remotely-accessible monitoring stations were downloaded immediately after each blast by the seismic provider. Following a review of the data by the seismic provider, the seismic records and any comments were emailed to the blasting company and other interested parties. As blasting progressed, the monitoring stations were relocated as needed to the nearest structures. Due to the compact size and self-contained nature of the monitoring stations, relocation was quick and easy. Relocation also allowed the opportunity for the seismic provider to meet with surrounding property owners to discuss the progress of the project and address any concerns.

Result:

In general, the outcome of this project was exceptional, considering the proximity to adjacent properties and the frequency of blasting. The seismic provider’s expertise was utilized in an efficient, cost-effective manner while the blasting company’s productivity was maximized.