Recent content by kngpenn

The upper floors will have floor trusses spanning the entire 25' width to bear on wood exterior walls. The elevated slab will only carry residential loading and have concrete walls on all four sides as support. Im thinking adding beams and design as one way slab is the way to go. Project in DC

I have a 4 story building that is 119' long by 25' wide. The lower floor has an elevated slab. Which is more economical? 1. Design the slab as a 1 way slab in the 25' direction? 2. Add beams down the 119' direction and design as 1 way slab. 3. Do number 2 and design as 2 way slab.

Does anyone know of a calculation procedure for enlarging an existing column footing due to additional loading? At the interface of the new concrete where bars embed in to the existing footing, there should be a calculation to determine the bars size and spacing based on the new loading. I've...

90 mph the wall is 16' tall

I trying to find an example of how to design a interior non-loading bearing cmu wall for out of plane seismic loading. Does anyone know of such example

I have a project in which I've just received the concrete mix design. The air content is 10% (by volume). I know the normal range should be around 6% to 7% (if subject to freeze/thaw) so I'm trying to figure out what would be the adverse effects of high air content in concrete. I know it may...

Typo.....I meant .107 (10.7%)

Thanks DST148!! I'm experiencing its better to have a highr R value as it produces a lower Cs used in the Base shear formula. The R=5 presents a Cs=.069 (7% of the building weight) where as the R=3.25 presents a Cs=1.07 (107% of the building weight).

Ordinary concrete shear walls R=5 Ordinary concentrically braced frame R=3.25 Therefore the R used should be 3.25, correct DST148? This is true steellion. I'm having to keep adding braces as the concrete shear walls want to pick up more of the load just as you said steellion. Another problem is...

I have a project that involves and existing building with a two-way slab floor system with concrete shear walls. I want to add steel braced frames as some of the shear walls are failing due to the additional mass of an additional floor we are adding. When using a mixed system for lateral such as...

This is a waffle slab with no beams, just dropped panels at the columns.

I have a project which involves a hospital designed in 1978. The client wants to add another floor above a section of the hospital which was never designed for future expansion. The roof is waffle slab construction design for a 55 psf live load. We need to get 105 psf live load for the new...

I am having a heated conversation with a contractor. Shear wall anchor bolts at the hold downs are subjected to both shear and tension correct?

AN EXAMPLE I MEAN... THIS IS WHAT HAPPENS WHEN YOU TRY TO WORK AND TYPE AT THE SAME TIME.

I HAVE METAL DECK WHICH MAKES A RIGID DIAPHRAGM. CAN YOU POINT ME TO AN EXAM PERHAPS?