Recent content by PittEng88

Thanks for the replies. I'm coming up with 36" walls right now based on the hydrostatic pressure alone, but there is a surcharge load from the pump station building which is pushing the walls to 42". @LittleInch: The well is this deep based on pipe inverts, site constraints, and required...

Hi Everyone, I'm looking at designing a fully buried wet well for a pump station, inside dimensions are 30' Long x 8' Wide x 27' Deep. The geotechnical report indicates that bedrock is pretty shallow in the area so the well will need to be keyed in. The problem is, that we are also next to a...

When you say T-beams, do you mean precast double tees or cast-in-place T-beams?

A1 is the area of the base plate. To calculate the bearing stress on the cmu, you need to calculate Abr, which is the smaller of: 1. A1*(A2/A1)1/2 where A2 is the base of the frustum of a pyramid or cone with the loaded area at the top and sides that slope at 45 degrees that is wholly contained...

I would look at distributing the point loads down through the foundation wall at a 1:1 slope and checking the bearing pressure from there using, as Jed mentioned, 1000 psf as an allowable bearing pressure. If it all works out, then you shouldn't have modify the existing footing.

Sorry, I completely missed "Garage" in the Title. Either way, you could use AASHTO, which is a great resource for concentrated wheel loads and their distribution. In the past, as a conservative approach, I have assumed the floor planks to be single span for moment and 2-span for shear to produce...

Is this for a bridge? If so, I would recommend checking out Section 3.25 Distribution of Wheel Loads on Timber Flooring from the 1992 AASHTO Standard Specifications.

I never considered that, but it does make sense. I guess the argument can be made that the deflections due to the masonry will be set/locked-in before the grout and mortar hardens. In the Section 1.13.3.1 of the ACI 530 Commentary it states that, "The deflection limits apply to beams and lintels...

Thanks for the responses! I agree that stress will not be an issue designing to the L/600 deflection. Is it just me or does that limit seem awfully strict? Especially since it includes dead and live loads.

Or I could just use a beam that works at that unbraced length. As long as it doesn't encroach on the headroom too much.

Thanks for the replies! Yes, I was planning on using needle beams for the demo. I was thinking about using angles every so often and thru bolting them through the masonry to help brace the top flange, but I think the studs will be a cleaner look at the end.

I am currently working on a project that requires a partial height removal of a CMU Wall for a building addition. A steel beam header will be installed to pick up the loads from the remaining portion of the CMU wall above. If the steel beam is only grouted to the underside of the CMU wall with...

Why not just provide a dbl. top plate for your joists to bear on and a 2x rim board for you to attach your plywood diaphragm to?

If he was talking about bearing on the plates below, then yes I would agree that it should be checked for the plate.

Posts are normally not checked for compression perpendicular to the grain because they are axial force members and the forces are assumed to run parallel with the grain of the member. Compression perpendicular to the grain is more of concern for beam bearing or where other members are framing...