Mat foundation design by hand
Mat foundation design by hand
(OP)
Anyone have any good references for designing mat foundations by hand. Not combinded footing with two columns, but mats that support equipment with 8 to 10 columns or mat foundations that support 10 to 12 pieces of equipment such as pumps, horizontal and vertical fuel tanks (10' diameter), etc.
I am trying to justify buying software to do the design of 10 different mat foundations on a project. I have used software to design all mat foundations in the past, but this company doesn't have software.
I would also just like to have the reference.
I am trying to justify buying software to do the design of 10 different mat foundations on a project. I have used software to design all mat foundations in the past, but this company doesn't have software.
I would also just like to have the reference.






RE: Mat foundation design by hand
Do you really want something to go by or do you not so that there is a reason to buy the software?
RE: Mat foundation design by hand
RE: Mat foundation design by hand
The hand calculations can get nasty real quick, and in the end you'd end up assuming a lot of things.
RE: Mat foundation design by hand
what i do is neglect the element right next to the point load and consider only the next element for rebar design..
any opinion..
RE: Mat foundation design by hand
Don't forget to check for punching shear.
RE: Mat foundation design by hand
RE: Mat foundation design by hand
i didnt get what you mean by this.. are you talking about creating a strip and doing a hand calculation of shear and moment diagram?
RE: Mat foundation design by hand
Not doing a hand calculation for moment and shear, but using the results to obtain workable values.
RE: Mat foundation design by hand
If I have a piece of equipment with a larger base plate I will usually apply its load as an area load to try and avoid the large concentrated load.
RE: Mat foundation design by hand
Couldn't you very closely approximate your bearing pressures when using compression only springs by dividing your max spring reaction by the area of footing it support (i.e. max spring reaction/(distance between springs * width of footing))?
RE: Mat foundation design by hand
RE: Mat foundation design by hand
but still maximum moment would come from the most stress element that adjacent to the point load..
RE: Mat foundation design by hand
RE: Mat foundation design by hand
RE: Mat foundation design by hand
If you tell the software to show you moments, you could add up the maximum moments per unit length of each element, multiplied by the width of each element on an assumed design strip and design for the total moment in the strip.
As you stated, bearing pressure is estimated as the force in the compression only spring divided by its tributary area.