|
cmu filled opening in existing concrete wall
i am filling an opening (26' wide x 16' high) in an existing 12" solid concrete wall (not tilt-up) with 12" cmu in a running bond pattern. the opening is currently installed with a folding (4 leaf) metal door that operates much like a closet bifold door. the metal door is a corrosion headache and leaks energy and water.
the new cmu partition will have in the middle a 16' high overhead roll-up door which i will anchor to the existing heavily reinforced concrete lintel/header of the opening. i am also installing a personnel door to one side about 3' away.
my quandry is that i wish to properly fill and reinforce the cells next to the overhead door, and i am uncertain whether i am required to "tie in" the top course with the existing lintel.
this is an issue of constructability, and i am uncertain about current techniques for pumping concrete horizontally to achieve a good bond beam.
i'd like to hear if anyone has tackled a similar issue and how it was solved.
thanks
jmm
take the new wall as high as you can and still be able to grout cells and horizontal runs. dry pack grout the rest. are you designing the wall to span horizontal or vertical?
the wall should tie-in to the existing to help eliminate cracking that will occur. you can never really be free of cracking but it can be better or worse. if you need the existing lintel to support the top of the wall for lateral loads, of course you'll have to tie to the existing. also, tieing to the existing will help with any differential movement of the new relative to the old.
to pump like that, you'll have to have holes knocked in the lintel block of the bond beam and use grout with a high slump. when you hit the top you have to dry pack or use a stiffer grout to plug the hole and finish what you need to do. it's not impossible but it won't be pretty. usually you'll have a rebar epoxied into the existing bond beam and the existing jamb to help tie the new to the old. |
|