You have me a bit confused there, you need a laptop that can handle CAD software or you need laptop that can handle being used at construction site where hammers and other things are being dropped on it?
If it's the first case, the range is pretty broad, any 17" laptop will be able to handle fairly well, you might need to pay extra to upgrade to more RAM, because that is essential for CAD software.
Give us a budget you are looking to spend on it and what specific CAD software you are planning to run on it and someone will be able to recommend some good choices.
If you need a sturdy laptop for construction/industrial environment to work in, one thing I'd like to point out, going with a 17" is probably not ideal, 14-15" out to be a lot more portable if you still want a large screen. That said, Lenovo Thinkpad is a fairly sturdy construction meant for business/heavy use, so take a look at those.