A trip through the U at LAX might be good for that. There's a lot of cool stuff going on with moving enormous concrete and steeel assemblies into place, though I think most of the time it's hard to see much of the equipment for doing it. Maybe from the top of one of the parking garages late at night. It's about an hour to get through the U and can be done on the way to somewhere else, like the science center or the beach.