For the stirrup function in beam shear capacity, the stirrups are the only thing holding diagonal cracks from coming apart, so why did you say that "Bars do not need to be surrounded to have mechanical bond, and do not need to be in contact to have a good lap length, but both effects need to be...
CELinOttawa, the reason rebars have grooves is so the concrete can bind to it.. the so called development length related to it. If you remove any stirrup or ties from beams or columns and put a new one. It is not connected to the original concrete and can no longer function as required (for...
If there are rusts inside bars inside beams.. how do you remove the rusts when concrete enclosed it. And If you inject epoxy into any hairline opening and the rust is isolated, would the rust further corrode the remaining bar inside the beam? How is this thing usually handled?
This is similar...
Isn't "beams that ARE built integrally with the support" the same as monolithic beam-column joint?
In the third case, are you referring to continuous beam? But taken in isolation, you can consider a span as "beams that ARE built integrally with the support".. so the second and third case can...
When one say beam span, is it the clear span of the beam or the span from center of one column to another?
Does it vary with different codes?
For example. My beam has length of 5.2 meters clear span but 5.65 meters center to center of the supporting columns. So is my beam length 5.2 or 5.65...
How do they intend to seismic retrofit any building especially the beams (no problem with columns as carbon fiber or increasing the dimension may work) but in beam it is problematic?
Note that in seismic design, the stirrups alone have to resist the entire 1.2 Dead load + 1.6 Live Load and...
...tests on the stirrups and came up with 370 Mpa instead of just 275 Mpa. So shear capacity from stirrups is about 182 kN or exactly
Vs = 0.75 * Av . fy . d /s = 0.000000142 * 370 Mpa * 0.485 / 0.1 = 182.01 kN
V(g) or shear due to gravity = 1.2 LL + 1.6 DL = 170 KN
So the stirrups is only...
The manual mentioned it can solve for probable shear Vp which is equivalent to Mpr(-)+Mpr(+)/length + (1.2DL+1.6LL/2) but even if I enable UBC 97 and chose Siesmic Zone D (Special Moment Frame), I can't find where to view Vp in Shear and Moment Diagram or elsewhere, it is not the EQ load...
You mean there is no actual plastic hinges that formed during real seismic activity anywhere in the world hence no pictures have been taken?
CELinOttawa, etc.. how does repair of plastic hinges compared to repair of diagonal shear failure?
Diagonal shear failure means the stirrups have...
But the longitudinal bars have already yield in plastic hinges, so the bars have to be replaced... isn't the beam just demolished and place new one again?
Is there any actual picture of plastic hinges formed in seismic regions that has happened before?
For concrete structures that form plastic hinges (in other words the flexural bars have yielded at the support), how are they commonly repaired?
Just curious as a construction management engineer.
The problem now can be simply categorized as seismic retrofitting of gravity load structures.
If the steel I-beam underneath the concrete girder is difficult to be moment connected to the column and connected to the beam as composite. Does it make sense if you will retrofit those gravity load...
Let me clarify. When earthquakes occurred to badly design building, the engineers will blame it on the earthquake and be free from reliability even if they design it badly! That is, some don't take responsibility and blame everything on act of god for any uneventful happening. This is the...
...addition to Earthquark. Next week I'll try to make him produce what is the biggest load combinations out of the 23 he used to give such a big shear *almost* equivalent to 2 x (1.2 DL + 1.6 LL).
After doing some rough manual computation with him (he doesn't know how to manually compute). I...
AELLC and BA,
In the Philippines.. engineers are free from liability in case building is damaged by any seismic activity so designers don't worry about damages caused by earthquake because they can always blame it on the earthquakes. So in a country where 99% of buildings are special moment...
Yes. The same beam. From bottom of beam to top of slab. It's 500mm.. so the entire depth of the beam is 500mm. If just the underside of the visible beam of a T-beam, then it's only 400mm visible. Of course when we specify a beam depth. We are talking of the entire depth of the beam from bottom...
BAretired. No. the Beam depth is NOT 600mm deep but only 500mm deep (half meter) as I mentioned in all my posts, all have same size of 500 mm depth and 300 mm width. Would this make it shallow in your experience? On a 6 meter span, the L/d would be 12. Is this horrors?
Before the structure was...
When you mentioned span/d ratio, do you mean the whole span over depth or shear span over depth? If the latter,
In the aci shear span/d ratio
a/d = 1 very deep beam
a/d = 1-2.5 deep beam
a/d = 2.5 6 shallow beam
a/d = very shallow beam
In the kani curve, very shallow beam would first fail in...
AELLC, in addition to the above, I'd like to continue with the following facts:
http://imageshack.com/a/img23/9432/50os.jpg
Please see above layout of the floor. The designers don't do manual computations because they are designing so many buildings so they need sophisticated program like...