Point Load on Reinforced Masonry Wall
Point Load on Reinforced Masonry Wall
(OP)
Hi Guys,
I have a wide flanged beam framing perpendicular into an internal masonry wall. This beam is a rafter and sees some axial force due to the wind loads travelling through the roof system and causes out-of-plane bending in the block wall.
I am planning on putting a steel mullion in the block wall to strengthen the masonry in out-of-plane bending.
Does reinforced masonry exhibit any punching shear type behaviour such as reinforced concrete and if so, can anyone direct me towards a good design reference?
I have a wide flanged beam framing perpendicular into an internal masonry wall. This beam is a rafter and sees some axial force due to the wind loads travelling through the roof system and causes out-of-plane bending in the block wall.
I am planning on putting a steel mullion in the block wall to strengthen the masonry in out-of-plane bending.
Does reinforced masonry exhibit any punching shear type behaviour such as reinforced concrete and if so, can anyone direct me towards a good design reference?






RE: Point Load on Reinforced Masonry Wall
I would expect it to behave somewhere between reinforced concrete and a clay masonry wall.
That said, there will be negligible two way action in the wall as the face shells will provide a plain of weakness and any horizontal reinforcement will be central. So check it for beam shear in one or two cores with maximum reinforcement and if that doesnt work then you will definately need to connect directly to the steel mullion.
Other option is to provide a horizontal channel along the wall to spread the load to a wider width of wall.
RE: Point Load on Reinforced Masonry Wall
Typical the masonry wall spans vertical for out of plane forces and is braced by the roof/floor or some other means. Lets say it's the roof. The roof is typically a diaphragm that spans to some type of bracing parallel to the force, either a frame or shear wall. If this is so then you dont' have punching thru the wall. If you are bracing the roof by the wall then the wall must cantilever up from some fixed support or must span horizontally to some support. I would think that whatever you need to transfer the force either horizontally or vertically in the masonry will will be more than adequate for some type of punching shear. You have to make sure you anchorage is sufficient.
Think thru your load path again.
RE: Point Load on Reinforced Masonry Wall
DaveAtkins
RE: Point Load on Reinforced Masonry Wall
If you decide to take the horizontal force component into the masonry, I don't think masonry codes typically address punching shear. However, if this is a fully grouted wall, I see no reason why you cannot use the same logic used in concrete codes to check this.
RE: Point Load on Reinforced Masonry Wall
Any chance of taking out, or cancelling out the lateral kick there?
If youcould, then the beam could be supported biy either flat bearing plate on top of the wall or in a beaqm seat, or a vertical plate anchor-bolyed or after-set bolted to the grouted wall.
Mike McCann
MMC Engineering
RE: Point Load on Reinforced Masonry Wall
There is a mezzanine level which extends through the roof frame so that is the reason for discontinuing the rafter.
I admit, conceptually, it is not the most efficient way of doing things here, but unfortunatley that is out of my control now.
Thanks for the positive replies.