# Stress Bulbs for strip "continuous" footings [closed]

How can I plot such a graph with Excel or Matlab by a uniform load q, and how can I see where the stress becomes 0.1q?

The loaded area and the equation is on the picture shown below, equation is highlighted in yellow   • The plotting in Matlab can certainly be done with a contour plot once you include the equations in your question. Apr 1, 2015 at 21:57
• @MuradNazari This is similar to some instantly recognizable geotech charts that can be found in any textbook. The two methods I am aware of to create these charts use either the Bousinesq equations (example) or the Westergaard equations (example). However, your chart does not match either of those charts. I need to know what method it is using. Apr 2, 2015 at 21:18
• @GlenH7 Ah ha! I found what method is being used here: it's Bousinesq for the stress increase under a flexible strip loaded footing (the method can be found in Das, Principles of Geotechnical Engineering). Since it is now obvious what method is being used I think you can reopen the question. Probably needs to be edited though. I can do that but not today. Apr 2, 2015 at 21:28
• @GlenH7 Thanks for mentioning Boussinesq (is it one or two s?). I use it very often in the context of contact pressures and deflections. Apr 7, 2015 at 21:06

You can use this formula to calculate it based on the x, horizontal distance and z vertical distance. Simply put z=0 and increment it say by 0.1 in excel while x starts from B/2. sample calculations  