Bifalgorithm post

A viewer recently asked whether this kind of structural design is actually strong enough, so today we're going to break it down using the physics we all learned in middle school. In a setup like this, if the columns are perfectly vertical, the load path is nice and straight, clear, simple, no fuss. But once you tilt those columns, things get a lot more interesting than just "the force takes a turn". So how do you figure it out? Let's walk through the mechanics. When the load from the upper floors comes down to that corner joint, the angled column has to push back with an opposing force to keep everything in balance. How big does that force need to be? That's easy. Newton's third law tells us that to maintain equilibrium, you need an equal and opposite force acting along the same line of action. So that's the magnitude we're talking about. But here's the catch. The column is slanted, so it's not on that same straight line. No problem. We just project that force horizontally onto the column's axis, and that gives us the axial force the column has to deliver, which equals n divided by the cosine of the angle. So the slanted column has to carry that much extra load just to keep the vertical direction balanced. At the same time, that reaction force from the tilted column also generates a horizontal component, and that horizontal push has to be picked up by the beam connected to the column. From all this, we can see the key takeaway. For these special members, under gravity loads, the slanted column takes a bigger axial load than a straight vertical one. Other than that, the differences aren't huge. But the beam tied to that slanted column doesn't just handle gravity loads. It also has to resist that horizontal tension, which makes it an eccentric tension member. If the tension is strong enough, it could very well become a small eccentricity tension member. And for those of you who are sharp, you've probably already realized that the rebar in this kind of member can't use lap splices. That's a no-go. So if you've thought through all these issues and also run the numbers for seismic conditions, then congratulations, your design is definitely solid.

A viewer recently asked whether this kind of structural design is actually strong enough, so today we're going to break it down using the physics we all learne…