03-30-2009, 03:32 PM
While hand calculation generally we assume pressure below raft constant. While in actual case axial loads along with moments are transferred to raft, resulting in non uniform pressure below it. So, punching shear check will be different in both case.
Also, in manual method, we treat raft as rigid. (Raft area= load/SBC & pressure= load/area). While SAFE treat RAFT as flexible. (pressure = ks*displacements).
Hope this will help.
Also, in manual method, we treat raft as rigid. (Raft area= load/SBC & pressure= load/area). While SAFE treat RAFT as flexible. (pressure = ks*displacements).
Hope this will help.
(03-30-2009, 02:21 PM)san333 Wrote:(03-29-2009, 03:47 PM)aslam Wrote: @san333,
Can u share SAFE file in which u have model piled raft? It will be gratefull to me.
I want to know how u model horizontal and vertical springs for PILE, in addition to vertical spring for raft.
RAFT can be modelled as SLAB. How pile is modelled? As column ? and then applied horizontal and vertical springs to it?
Hi, I modelled the pile as a vertical spring constant (Column support then choose the spring constant) and the Raft as a slab.
A little bit out of topic. Do you know how the punching shear check work at SAFE. Why sometime I find out the punching shear ratio more than 1. Then, I check using hand calculation it is still okay.
btw, I'm just new engineer with less than 1 year experience. so, need more guidance from the senior here.