I need to know a good estimate on the weight (psf) of Steel Bar Grate Stair Treads & Stair Stringers. I have a stair imposing loading on a slab. I need to check the slab for the laods, but I don't know what the dead loads are for stairs of this type. I just need a safe ballpark assumption.
Deep Beam Design - One span w/ Cantilever one side only:
When designing a deep beam by strut and tie I'm getting bogged down in determining the appropriate dimensions to apply to the faces of the struts.
In the ACI 318-02 Code Reference example ACI calculates these faces based on the lowest...
Anyone know the hand calculation for the torsion constant (J or sometimes shown as Jt) of an inverted tee section of concrete? My college mechanics of material book only gives examples for thin wall tubes and pipes. I'd rather know how to do it by hand instead of letting a computer tell me the...
I am designing a beam that will pick up (2) other beams. The supporting beam is pocketed for the (2) beams, so there is torsion induced in the beam. I have designed the section for the shear and torsion, and it is adequate. My question is how to I make sure that the beam will not rotate such...
When using hollowcore in a parking deck are tooled joints required in the topping at every plank joint? The PCI recommendations for parking structures indicates that they are recommended, but is it necessary at every joint? Would every 12ft or another spacing corresponding with 4ft plank work...
I'm using High Strength Coil Rod for a column to beam connection. When anchoring the rod into the column I have an edge distance of 3 1/2" (round column, square rod pattern, 4 rods each 6" off CL and 90deg apart).
Since the rods are threaded they achieve better bond than a smooth bar. Can I...
Using computer software to generate precast and prestressed concrete beam designs is a usefull tool, but it seems that for some particular cases the design becomes too conservative.
I've run across the following when designing simple span uniformly loaded beams,
ØMn < 1.2Mcr and ØMn < 2.0Mu...
How do I go about designing an angle as a beam (a short one of course)? My angle is loaded on the inside face of one of the legs (not an upside down L where stiffeners could be added) so it is not stiffened, and it is not braced the full length. I've looked through the LRFD (2nd Ed) and it has...
I am designing a precast beam that meets ACI 318 deflection criteria, and the beam meets it fine, but I seem to have a mental block in allowing a beam to have 3/4"-1" of deflection (20ft span) under full loading. It should be noted that my live load is very small in comparision to my dead load...
Along the lines of commute time (thread731-125181)...
(Which I should add is fun to read!)
How many hours are engineers working per week?
And...
How flexible is your schedule? (Are you an "8-to-5"er or were you able to choose your hours?
I'll go first,
40hrs per week (99% of the time)
8am -...
I am designing a 12" deep precast slabs that span over a creek at a residence to resist HS20-44. (2-10ft wide, 20ft span, 2" composite topping) I have designed it for flexural capacity and shear, and it meets the deflection and crack criteria. How do I specify the transverse steel? Is there a...
I am designing a 12" deep precast slabs that span over a creek at a residence to resist HS20-44. (2-10ft wide, 20ft span, 2" composite topping) I have designed it for flexural capacity and shear, and it meets the deflection and crack criteria. How do I specify the transverse steel? Is there a...
I am designing a 12" deep precast slabs that span over a creek at a residence to resist HS20-44. (2-10ft wide, 20ft span, 2" composite topping) I have designed it for flexural capacity and shear, and it meets the deflection and crack criteria. How do I specify the transverse steel? Is there a...
I am designing a 12" deep precast slabs that span over a creek at a residence to resist HS20-44. (2-10ft wide, 20ft span, 2" composite topping) I have designed it for flexural capacity and shear, and it meets the deflection and crack criteria. How do I specify the transverse steel? Is there a...
Does anyone know how to specify the length of a coil rod embedded in concrete to develop the full strength of the rod? There are charts for re-bar, of course, but is there a similar calculation for coil rods?
