We get bombarded with CAD file requests. Everyone wants to construct with a CAD file. While it offers many advantages, especially with 3D modeling, often pertinent information is located on the plans that isn’t necessarily covered in a CAD file. As site crews are relying more and more on GPS technology and survey files, the opportunity for errors are increasing in the field. It is becoming common for fine details to be missed due to an inaccurate survey file and even worse, for contractors to become reliant on the GPS screen and less reliant on the official plan set.
It’s a technological progression that most industries are experiencing. Black box syndrome. Technology dependence with no regard to the craft. It’s a dangerous game my friends. How can we avoid the pitfalls of technology while still supporting the clients needs?
- We must hold the paper copy of the plans as king. CAD files created for construction/surveying by third parties are secondary to the approved plan set. The two should complement each other but not replace.
- Require contractors to review the plans at the pre-construction meeting and check the survey file against the plans. In addition, when the cad file is provided a release of liability should be considered. The release should dictate that the approved hard copy set is the official working plan.
- If there is disagreement between the two a RFI (request for information) procedure must be in place. Deviations from the plan may have to be removed and replaced at the contractors expense.
- Some things are too advanced in means and methods to depend on GPS shots. Sometimes the mini-excavator needs to be swapped for a shovel. There are times when a transit or total station needs to be used for finer, more precise results.
- A good contractor can do math. I have met old timers that rattle off computations faster than IBM’s Watson. They probably can’t play a lick of chess though. This seems to be less and less common as us younger folks enter the arena and we need to be aware of the weaknesses that the technology we embrace brings to the table.
These are just a few thoughts of the need for craftsmanship and using the right tool for the job. It is also imperative for the engineer to be involved in the process with open communication and frequent inspections.