caseypoi23
Structural
- Jul 26, 2016
- 11
trying to understand how SAFE works using a simple model:
I have a grade beam sitting on soil, with an huge uplifting vertical force towards one end. by hand, the grade beam overturns despite the grade beam's weight (the uplift force is way more than the gradebeam weight, btw - the gradebeam should fly into space). by SAFE, 1) if assigning a soil to the gradebeam, pressures seem to be in tension (?) on the uplifted side, or 2) if using line springs along the longitudinal ends of the grade beam (and compression only), all arrows seem to have vertical reactions...?
questions:
1) i want SAFE to say that HEY - MODEL IS UNSTABLE. does SAFE do that?
2) if I have a subgrade modulus of 200psi/in, how do i convert that into a spring stiffness of units kips/in?
note: my actual grade beam is far more complicated with many point/uniform/distributed loads, along with a shear wall created tension/compression forces, FYI. I'm using this simple model to ensure I understand how SAFE works.
thanks!
I have a grade beam sitting on soil, with an huge uplifting vertical force towards one end. by hand, the grade beam overturns despite the grade beam's weight (the uplift force is way more than the gradebeam weight, btw - the gradebeam should fly into space). by SAFE, 1) if assigning a soil to the gradebeam, pressures seem to be in tension (?) on the uplifted side, or 2) if using line springs along the longitudinal ends of the grade beam (and compression only), all arrows seem to have vertical reactions...?
questions:
1) i want SAFE to say that HEY - MODEL IS UNSTABLE. does SAFE do that?
2) if I have a subgrade modulus of 200psi/in, how do i convert that into a spring stiffness of units kips/in?
note: my actual grade beam is far more complicated with many point/uniform/distributed loads, along with a shear wall created tension/compression forces, FYI. I'm using this simple model to ensure I understand how SAFE works.
thanks!