detailing confusion

[mezzoms]

Dear all
i am confused about details of beam to column connection and reinforcement of wall corners
and i do not know what are the differences between it

Please see the attached pages .these are from a book with basis of EC2
1.detail A in Ms2 sheet use the u-bars states that distance x must be more than anchorage length to use it otherwise use B or C
2.in sheet mw2 the detail of wall corners with u-bars does not state or even refer to distance x limitation as detail A in ms2,also in sheet mw3 detail of connection between wall vertical RFT and slab RFT does not state the limitation of distance x in detail A to be used.what are the difference between the two cases between it ?
.why it states that in beams and not walls?
.what happen in case of distance x less than anchorage length and the full anchorage length will be completed after the bar re inter the beam at bottom of itself?


Please give me your opinions
it drives me crazY
mezzoms

 

[mezzoms]

Ms2 sheet

 

[mezzoms]

Mw2 sheet

 

[jayrod12]

Note: This is coming from a non-seismic point of view.

For the question Why in beams but not slab,

I would say because you need to develop the bars for the beams, hence the minimum 'x' distance must be equal to anchorage length, but the wall horizontal reinforcing at the corner is acting more like a column tie. So there's no minimum development length requirement for that detail.

For your second question, You will not have full engagement of your bars if you do not have enough anchorage. Therefore you would not be able to account for the entire beam moment to be transferred into the column. If you have designed your column to beam connection for less than the full design moment, then you technically could argue that you don't need full anchorage length.