Beam Seat Connection for Existing Masonry

[406Eng]

Wondering if anyone has dealt with a similar situation or has good ideas on how to resolve this....

I am currently completing a renovation design for an 1890s unreinforce structure with Maonsry shear walls (brick) & interior wood beams and columns. The renovation involves replacing the existing beams & columns and addressing some sag issues that the building has been experiencing lately.

I am trying to find a way to install beam seats (for bearing & lateral forces) at the bench location where the beams meets the masonry wall (see attached figure). My question is what methods are feasible to install the rebar of the beam seat into the masonry wall? I have considered both drilling larger holes for the rebar, installing the beam seat, and grouting the holes. Also I have contemplated removing some of the additional brick and replacing with a concrete pad and anchoring the beam seat that way...my biggest concern is I am unsure how both methods will behave with the existing masonry wall. Thoughts on these or other approaches for installation?
Thanks ahead of time for any input.

 

[bob33]

I would remove existing bricks and build in the anchors using bricks and mortar to help get a good bond to existing wall. I would also provide at least 6" bearing onto the wall for glulam beams.

 

[OldBldgGuy]

Stop and think about what those rebar anchors are doing. If you're looking for lateral restraint in the line of the beam, they will simply pull the bricks off the wall in front of them, the shear strength of the mortar joint below where they stop governs. If you want uplift, or some sort of rotational restraint, tension in that same joint is your limiting factor.
You have to realize that the wall beyond your seat and anchors still exists exactly as it did before you arrived.
Design your beam for gravity bearing. The wood beam won't have more compressive strength than the masonry, and a steel plate is simply something you want because we always use them in new construction. It does nothing for you here, you can bear wood on wood so why can't you bear wood on old masonry? You will get no lateral restraint in the direction of the beam, plenty at right angles if you build it in with masonry, and like it or not, that's life. Make a nice flat mortar pad, sit your beam on it, and you've got exactly the same capacity as every expensive and difficult-to-build option you can dream up.
I'm sure we'll get plenty of comments on my response.

 

[kipfoot]

I'd suggest something like your second option.
I like pouring a concrete bearing block because the contractor can screw the form to the surface of the brick and set the top edge with precision to the elevation that works, regardless of coursing. You can size the block to distribute the load to a comfortable bearing pressure, and place a plate at the center of the wall so that you limit eccentric loading.