special moment, ordinary and intermidiate

[gyroman10]

i just wanted to reconfirm that when modeling and designing a frame, the only factor that differs accoridng to the type of frame is the R factor (structure type factor)when calculating Seismic load. Rest all is the same, desiging method, analysis, loading, and other considerations. RIGHT ?
and then detailing off coarse is different for all different types of frames.

 

[prsconsultant]

Analysis procedure is same for all MF types. Design procedure is different for each type of MF. I don't know if you are using concrete or steel. If it is steel there are limitations on the compactness of the sections, requirements of lateral bracing, panel zone strength etc. Similarly for a concrete SMF there are limitations of span/depth, width/depth, beam-column strength ratio etc.

 

[gyroman10]

beam-column strength ratio ! what clause of ACI suggests the column beam strength ratio for specific frame.

 

[prsconsultant]

Special Moment Frames (SMFs) are frames conforming to the requirements of Sections 21.1 through 21.5 of ACI 318, in addition to the requirements of OMFs.

Strong column weak beam: flexural yielding in the girder elements. Columns must, therefore, be stronger than the flexural capacity of the girders.

Compact proportions for the girder and column sections, along with closely spaced seismic ties or hoops for confinement of concrete in the regions of potential flexural yielding.

Column interaction flexural capacity greater than 6/5 times the value required to develop girder yield.