Underwater blasting

The main difference in underwater blasting from open pit or underground blast operations is the presence of a water column covering the surface of the blast. .

However, this water layer makes everything more challenging and complex. Imagine a rock mass you have to blast but you cannot see it or the effect of vibration throughout water and soil? Or maybe imagine how to safely carry out an operation in a place with limited space or with intense maritime traffic of vessels around? These are some of the challenges we face every single day in underwater blasting projects around of the word.

MAXAM has a great culture on safety, encouraging people to talk, think and improve anything related to safety. Our robust working procedures and reliable technologies, aligned with a constant training of our people and collaborators, makes MAXAM’s underwater blasting operations a safer working environment. This is a fundamental ground for all our technical and operational performance. Thus, for the success of an underwater blasting design, some specific requirements and compatibility between safety, fragmentation, ground vibration and Production rates are necessary.

The undesired environmental effects are strictly controlled, eliminated or minimized. Ground vibrations, hydraulic shock waves and blast fumes are some of the phenomena that we control, model and monitor in order to ensure the best blast performance. For similar charge configurations, the vibrations are potentially bigger in underwater than traditional open pit blasting. This is a consequence of bigger powder factors, over confinement and some extra “package” of energy transmitted from water to the ground. What is desirable is a balanced blast design. Limitation on vibration level means control of energy released by explosive, on contrary to guarantee efficiency and fragmentation usually requiring more energy. By calculating key parameters, a fine-tuned blast design is the guideline leads to a successful blast.

Underwater blasting usually is part of dredging and marine construction works. .

The technological combination of drilling and blasting must be such that permits to cover the volume as faster as possible without affect the required fragmentation and vibration levels. Normally, the drilling capacity will be defined the rhythm of the operations; however, the blasting solution must be compatible with this demand. On the other hand, moving hazard material among alive channel traffic, throughout multiple transportations and guarantee continuous supply product with good quality is a test for a company’s supply chain. For MAXAM, from planning raw material to selecting qualified transportations; from import/export process to hazard material traceability, from quality control to even type of pumps, we know in detail how to guarantee our clients a secure and reliable supply chain. Our objective is to let clients never waste a second on waiting for the arrival of explosives.

The use of a highly energetic bulk explosive, the RIOFLEX MARINE, allows MAXAM to optimize drilling patterns by improving fragmentation and increasing operative cycles of D&B. This positive impact of production ratios is one of the key points for a successful project. RIOFLEX matrix is classified as an oxidant (5.1) which permits easier transportation than explosives. The Matrix oxidant became only an explosive in situ, that is, the RIOFLEX Matrix is sensitized on the last stage when the product is inside of the hole. The RIOFLEX is an explosive agent classified as 1.5D, UN No. 0332. Once sensitized, the density of RIOFLEX is fixed by the cross-linking process and will not drift through the influence of environment. This process makes the product resistant to water and renders impervious to the ingress of aggregate stemming or migration of RIOFLEX through the cracks and fractures.

On the other hand, rock fragmentation and bulk are equally important, and it is one of the most relevant outputs. In underwater blasting operations, the achievement of an ideal fragmentation is essential for an economic dredging. The fragmentation and required powder factors vary depending of the dredging equipment and type of rock. Any oversized rock will slow down the whole operation: big boulders requires more time for dredging machines; and if the rock size was even bigger, it would need to use secondary blasting which costs much more than the production blasting.

A group of talent team of professionals in underwater blasting. .

Among many other things, innovation is one of the most important. New tools like RIOBLAST design and simulation software; new models to predict and simulate ground vibrations and hydraulic waves; methods to control the fragmentation; development of a complete set of new generations of underwater blasting cassettes, everything aligned with the strong commitment to continuously improve safety, quality and efficiency of the projects, makes MAXAM on the road of the future.