Compression Steel in Tension
Compression Steel in Tension
(OP)
I have a little problem that I would enjoy some guidance on. I am desinging a beam that will be cast against the ground. The beam dimensions are b=16" h=12" and the depth to compression steel is 3.75" and depth to tension steel is 8.25 in. The problem I am having is that when I set up my Whitney stress block, at equilibrium, my c value is less than the depth of my compression steel and therefore it is acting in tension. It takes a ridiculous amount of tension steel to move the equilibrium point to a depth greater than the compression steel. The reason for the compression steel is that the beam may be subjected to negative moment forces as the beam is continuously supported. If anyone has some insight, it would be greatly appriciated!






RE: Compression Steel in Tension
RE: Compression Steel in Tension
RE: Compression Steel in Tension
RE: Compression Steel in Tension
RE: Compression Steel in Tension
In any case even if I understand and agree on the general convenience of designing flexural members to have failures by yield of the steel in tension instead of concrete crushing, I see that enforcing so for every case may not be entirely logical. I mean, you can have covered six times the design moment with a beam to fail with the concrete in compression, and still have to add more steel to ensure that the failure will be by steel in tension. 1 vote no, for cases as extreme as this. This view was once sustained for footings where once you had covered 4/3 of the required design solicitations it didn't matter if the failure was going to be fragile; a minimum steel to ensure that the kind of failure for the footing would be soft was not then enforced.
RE: Compression Steel in Tension
RE: Compression Steel in Tension
RE: Compression Steel in Tension
This "beam" is just slightly larger than a conventional footing for a house.
RE: Compression Steel in Tension
RE: Compression Steel in Tension