Information Needed

I am looking for a noninvasive method to determine the structural integrity of a mine seal. The seal measures 16 ft tall, by 20 ft wide and is 4 feet thick (it was constructed using sacrete and foamed water). The seal was poured in three successive lifts. I can only access the seal from one side. Thus far I have used a Schmidt Hammer and Ground Penetrating Radar (which shows some anomalies). I also have samples of the material that were obtained during the construction process that will be tested.

I am not sure if the data from the Schmidt Hammer tests represents the condition of the seal over the entire four foot thickness. Any ideas or recommendations for methods that might yield better information would be greatly appreciated. Be advised, the method recommended MUST be noninvasive.

 

[Ron]

Try one of the instruments from Olson Engineering. Check their website. You should be able to use low frequency ultrasonics to check the integrity, though "one-side" access does present some limitations.