Blasting Specifications

[geotekker]

I am anxious to get some feedback from my geotechnical colleagues regarding how they handle their involvement with projects that require blasting to permit rock removal. We are frequently asked by contractors and architects to either a) put together a blasting plan or specification, or b) review and approve someone else's blasting plan. It has been our opinion that all responsibility (means and methods, safety, monitoring, etc.)for blasting should remain the contractor's. Is this the norm for the geotechnical industry?

 

[PEinc]

Blasting is a specialty that should be handled by specialists. Refer the contractor or architect to someone with blasting experience. I would think that a reputable blasting contractor could steer them toward an experienced engineer.

 

[msucog]

i concur...blasting contractor and/or someone else qualified to take on such liability should be the responsible entity

 

[fattdad]

I would agree that the specifications should require the specialty contractor to submit a blasting plan. The problem is do you have any idea what constitutes a reasonable blasting plan? If there are neighboring properties, will there be pre-blast inspections and if so who's providing them. Are there velocity, acceleration, displacment criteria for the nearest structure or property line. Is the blaster required to perform an instrumented test blast to show seismic attenuations for varying charge weights? If you just say, "give me a blasting plan" and have no idea of what's going on, heck, you may get some dude that says, we're drilling holes, setting charges and blowing a horn.

Just for the record, I don't do these, but have been in some situations where I wish the blasting plan/specifications were better.

f-d

¡papá gordo ain’t no madre flaca!

 

[Gimbli]

Gatorcock; ask the "wiseman" Dr. Bloomquist!!

 

[mudman54]

the best input we, as consultants for the owner, can provide is to clarify the blasting control criteria. that would be to specify the allowable peak particle velocity (PPV) for the structure we are trying to protect. there are some relationships between PPV and scaled distance that you can use to figure out if the blast plan might exceed the vibration criteria. oriard is the authority on this subject, so see if you can find some of his papers.

 

[cvg]

recommend the following references to help you write your blasting spec requirements:

Department of the Army – Engineer Manual No. 1110-2-3800, Systematic Drilling and Blasting for Surface Excavations

Department of the Army – Engineer Manual No. 385-1-1, General Safety Requirements, Section 29 - Blasting


Also include the following language in the spec:

In Part 1 of the conceptual blasting plan a complete summary of proposed transportation, handling, storage, and use of explosives, and include the names of personnel who will supervise blasting operations, written evidence of past experience and competency, and a minimum of three references for each such person.

 

[msucog]

http://www.usace.army.mil/publications/eng-manuals/em1110-2-3800/entire.pdf

http://www.usace.army.mil/publications/eng-manuals/em385-1-1/entire.pdf

 

[exploengineer]

Actually, I specialize in this area. Every project is different. Only someone with a lot of experiance and licensing in blasting should write specifications, etc.

Frank Lucca M.I.Exp.E.

http://www.terradinamica.com