- #1
TimSmall
- 11
- 0
I'm doing some work on my house at the moment, and have had a design produced by a structural engineer for a steel I-beam to span a newly made (4 meter) opening in a brick wall. They've given me a design (see the attached picture for my interpretation) for the bearing of the I-beam which I can't get my head around (I've phoned and checked that's what they definitely intended, and they've confirmed that it i...). I have no engineering, but I did study Physics and Maths+Mechanics to English "A-Level"...
The steel I beam has a 12mm steel "spreader" plate underneath it (or rather under the 150mm piece of it which bears on the wall), which is not welded to the I beam. As far as I understand it, the job of the spreader plate is to distribute the load which is imposed by the steel beam over the underlying masonry so as not to put it under excessive compressive force, but I can't see how that spreader plate is going to do this. Moreover, won't the masonry pier itself end up with 47.3N acting on a line only 75mm from it's edge (maybe closer to the edge if the beam deflects a bit)?
If both the wall and the I beam ran the other way (i.e. at right angles to the span of the I beam when viewed on plan), then I can see that the spreader plate would work just fine (and I've seen such designs both on paper and built). Similarly, if the I beam extended the extra 180mm over the top of the spreader plate, then I assume there would be no problem there either (but then the plate itself would be redundant)?
I'm hoping that my doubts are unfounded, and the design is fine... Any comments?
The steel I beam has a 12mm steel "spreader" plate underneath it (or rather under the 150mm piece of it which bears on the wall), which is not welded to the I beam. As far as I understand it, the job of the spreader plate is to distribute the load which is imposed by the steel beam over the underlying masonry so as not to put it under excessive compressive force, but I can't see how that spreader plate is going to do this. Moreover, won't the masonry pier itself end up with 47.3N acting on a line only 75mm from it's edge (maybe closer to the edge if the beam deflects a bit)?
If both the wall and the I beam ran the other way (i.e. at right angles to the span of the I beam when viewed on plan), then I can see that the spreader plate would work just fine (and I've seen such designs both on paper and built). Similarly, if the I beam extended the extra 180mm over the top of the spreader plate, then I assume there would be no problem there either (but then the plate itself would be redundant)?
I'm hoping that my doubts are unfounded, and the design is fine... Any comments?