- The construction industry has shown a decline in productivity over the past 30 years.
- 3D laser scanning holds the potential along with machine guidance, to reverse this trend.
- Tunneling is one of the most obvious places where laser scanning can be invaluable.
To me the best example of where time is money is in construction. I grew up in this business and it is the reason I became a civil engineer. (Trivia Question: Why are we called “civil” engineers? Because before that title emerged, all engineers were military engineers.) There is something narcotic about being on a construction site, and seeing things get built. If you have not done this, you should at least watch the Discovery channel shows on BIG construction projects.
In the early 1980’s I had 5 survey crews providing control for one of the leading building contractors in Boston. We used 1 minute transits, 100 foot steel tapes and plumb bobs, and we were always within a quarter of an inch over the entire site, which could be 300+ feet in each direction. Now that was surveying. 3D laser scanning was not even a dream.
And since that time – the early 1980’s, what is the only industry in the US to show a steady decline in productivity? You guessed it – construction. Over the past 30 years the AEC – architecture, engineering and construction industry has been the target market for a tremendous amount of technology, but anyone in the business will tell you that in general, construction just does not get it. There are exceptions and things are starting to change, but there is still a long way to go before the “C” catches up to the A&E.
One bright spot in this is the potential application of 3D laser scanning. (The other is the use of GPS for machine guidance and control.) The areas where laser scanning is the obvious solution today are tunneling and offshore oil platform retrofit. It’s a million dollars per day to shut down an oil rig. It makes a lot of sense to use laser scanning to insure that the new module is going to fit.
Tunneling has always been the toughest challenge for surveyors. A tunnel surveyor was always the “cream of the crop”. Imagine trying to maintain control points in that environment, where small errors in alignment particularly at the start can prove disastrous after a couple of miles of tunneling. Or in trying to get accurate 3D measurements of the tunnel bore. 3D laser scanning is the only answer.
But as is always the case, whether it is new construction or a retrofit of an existing tunnel no one wants to stop the work, or traffic to allow for the surveying to be done. That is where the speed and accuracy of 3D laser scanning becomes so valuable. In some shorter tunnels time is being reduced even more through the use of mobile scanning.
As I have mentioned before I firmly believe that most construction projects could benefit from the use of a laser scanner on a daily basis, if only to document progress and/or avoid costly litigation. But beyond that it can provide the critical input to the 4D construction programs that the major CAD vendors are promoting.