Rafael, I'm just using an obsolete mobile so I cannot see your post for now. I'm sure its worth commenting. Nevertheless, I would be very glad if you can show us how you exactly model (using Spider Project) say: Construction of Bored Pile (Please forget about concrete foundation or footing). I think bored pile is more precise. Say given data are the following: One (1) Reinforced Concrete Bored Pile, 1.5 meter diameter and say 20 meters deep. Please model a realistic schedule considering necessary equipment, sequence of activities, volume or quantity of materials, sequence of concrete pouring (considering travel time from the nearest batch plant is 1 hour)and of course manpower according to skills, please consider as well when to reject the concrete mix once delivery is delayed. This is just a single activity with necessary components where you can make the best model and apply only automatic resource leveling in one click. Thank you and awaiting your prompt response.