hi to all, i agree with all of you. I think that in some case you should check if the diaphram could take the shear force at that point or the tension/compression developed when the diaphram deflects.But i insisit that is a good practice to provide a drag at every reentrant corner.
LG
Hi is a silly quick question about the ubc 97 and post tension slabs.
Do we have to provide a minimum reinforcemnet for a PT slab designed only for crack control? I have a plan check correction asking for this and we ussually don´t provide any,just the tendons. As always thanks a lot
LG
HI kano23, You should notice that the rho factor should be calculated for each direction and for each story so you might have diferents rho in each direction and in each story. Also the way of calculate de rmax depends on the structural system that you use .My last advice, if you are using the...
Archeng59
The Columns pass through the beam and are supported by a pad footing. The grade beam takes the moment of the column with a the couple generated by threaded rebars welded to the flanges of the steel columns and the compresion on the concrete.The footing takes all the axial load and...
rogelio,
You could import a DXF file from autocad. you should draw the entire structure in any layer except the 0. Start the drawing form the 0,0,0 coordinate. i don´t remeber very well but i think that when you import the file, sap ask you in what direction the vertical axis is defined.
I...
ARCHENG59: No, im talking about a grade beam a beam below of a moment frame that is used to resist the moments at the bottom of the columns.
i would like to know what is the minimum reinforcement for this elements.
By the way,We ussually design continuos footings as a grade beam and we specify...
Hi i Wanted to know about the minimum reinforcement on grade beams. we ussually use the minimum reinforcement for shrinkage and temperature. I wanted to know if this is ok or if we´re missing something. The amount of steel with this minimum reinforcement is huge compared with the requiered...
HI, swelm
Could you please more specific? i don´t now what is your problem/question. try to be more specific in tour post so we could help you
thanks
LG
Alumpkin i´ve checked the Bowless Foundation Analysis and Design book and in chapter 9 you will find an example of a ring foundation for a circular water tank as a beam on elastic foundation.
LG
alumpkin, so you dont have to calculate the walls of the silo? is a`premaufactured silo and you only have to design the foundation? is this alright?. I think that overturning could be critical when the silo is empty, and seismic when the silo is totally filled. Also i think that a mat...
hi alumpkin
well i´ve designed two or three silos some time ago. i used the ACI code and a book of juan Ravennet that is in spanish. its quite simple but you have to take into account that depending on the height to width ratio(>2.5) the stresses in the walls or the base are different and you...
You calc the tributary areas per the dead load and live load for gravity columns, and if you have seismic you could take a lower value of stress or lets say1.6P/ 0.35f´c in ACI code for lateral resistant columns to take into account the seismic forces. This is like a fist approach. So when you...
hi nimaoy
You should follow the ash060 suggestion. You have to calculate the Ag(total area).So if you want a square column the side B will be = (Ag)1/2.
LG
Hi,
You definitly should look in the breyer "Design of Wood Structures". The deflection of a sherawall basically depends on :
Chord bending
Shear
Nail slip
Anchorage Slip
with this four terms you could calculate the deflection of a shearwall. If you´re using the UBC 97 you have to calculate...
Hi,
im not too familiar with the ACI code. i used to calculate with the din code (Germany). In this code you use a stress for Concrete considering let say 1.2% of reinforcement and a 2.1 safety factor. Then you divide the total load per column by this stress and you get the requiered area of...
I think that you should model this frame with some software like ram advance or risa 3d. For this kind of structure the R factor should be very low Lets say 2.2 or 2(like a cantilever column). You should be conservative and show the plan checker that this structure really works. The main...
Hi Guys, i wanted to know if any of you could recomend a good composite book, Bacause i have to design a 4 stories wood framing and composite structure and i dont have to much experience on this kind of structures.
Thanks a Lot !
LG
Hi i agree with CoEngineer, i always put my rebars on center to take positive and negative moments. we always calculated as a Restrained retaining wall, But we do quick calcs as cantilever to provide a temporary backfill height. i think that the floor diaphragm could take this force, maybe the...
