gonutsdonuts
Structural
- Oct 8, 2013
- 12
Hey all,
I feel like I'm losing my mind. I'm trying to estimate a load demand due to lateral creep and shrinkage on a column/drilled shaft combination we have and then compare that to a FEA output from our model, but I can't get anywhere close. My approach has been to take the stiffness of the column, the stiffness of the drilled shaft, and then combine those together as they would be springs in series. Here are the basic equations I'm using:
K.col = 3EI/L^3
K.DS = 3EI/L^3
K.ef = 1/(1/K.col+1/K.DS)
This seems super strait forward but we're over estimating the model by about 200%. We've checked the column from the model alone, we predicted that fine. We've checked the DS from the model alone, we predicted that fine, but when we combine the two everything goes haywire. I'm thinking it's more likely me than the model. Any thoughts?
Note: looking at the moment and shear distributions it should definitely be acting like a cantilever.
I feel like I'm losing my mind. I'm trying to estimate a load demand due to lateral creep and shrinkage on a column/drilled shaft combination we have and then compare that to a FEA output from our model, but I can't get anywhere close. My approach has been to take the stiffness of the column, the stiffness of the drilled shaft, and then combine those together as they would be springs in series. Here are the basic equations I'm using:
K.col = 3EI/L^3
K.DS = 3EI/L^3
K.ef = 1/(1/K.col+1/K.DS)
This seems super strait forward but we're over estimating the model by about 200%. We've checked the column from the model alone, we predicted that fine. We've checked the DS from the model alone, we predicted that fine, but when we combine the two everything goes haywire. I'm thinking it's more likely me than the model. Any thoughts?
Note: looking at the moment and shear distributions it should definitely be acting like a cantilever.
