06:26 Oct-28-1999 Doug Mendes NDT Inspector, R & D Imetrix Inc., USA, Joined Oct 1999 7
Re: Inspection of earthquake damaged concrete Michael there are many areas of interest in concrete inspection,aggregate(grain) size,rebar location, rebar corrosion,and internal or surface cracks just to name a few. Since you mentioned bridges, rebar corrosion and cracks would most likely be your primary areas of interest along with corrosion detection of the rebar.
All of these items are important but if you add into the equation of your support columns being in water and then add the difference of salt vs. fresh water the outcome of your examinations will vary. Since all of these variables could apply to you i'm limited to the amount of help I can provide. There are many methods of concrete inspection available but thier effective depth is dependent on the condtion sought for in the concrete.I suggest you get more specific with your question.I hope I have been of some help to you.
: What methods are available for the inspection of concrete in use as bridge support columns structural pillars etc?
: I have heard of UT thru transmission and ground penetrating radar but what thicknesses can be examined.
Re: Inspection of earthquake damaged concrete I am currently working in Taiwan where recently we have had major earthquakes with 1000's of buildings destroyed and damaged. The damaged buildings (and bridges) have some uncertainity regarding their structural integrity. To compound the problem it has be noticed that many of the collapsed structures had poor workmanship.
Therefore any NDT examination would have to detect both poor workmanship (voids, lack of aggregate, no rebar etc) and structural damage (laminations, cracking),