what are the chances?
In a previous post (here), we determined the size glulam roof beam required to not deflect more than 1.00 inches (under design load). We arrived first at a size 6.75 in. x 27 in., but it was not quite sufficient. …
Tag: deflection
Absolute Deflection
Let’s look at a situation where, after construction, it is required that a certain roof beam experience a deflection of not more than 1.0 inches (in.). The deflection limitation comes about by a required clearance between the ceiling and some …
Bounce on the Movie Set
was called once to a movie set. It was in an old house, out in the country. There was considerable `bounce’ in the upper story floor, and they wondered if it was `safe’ (… to do their filming). I did …
AITC 119 and EEEE
I was doing some reading in AITC 119 Standard Specifications for Structural Glued Laminated Timbers of Hardwood Species, Section 4.1.6 … “ … modulus of elasticity, E, values herein are the average values … The modulus of elasticity of wood …
Jamming Jack Studs
The nice thing about a stiff beam is that it won’t sag much. The not-so-nice thing is that it won’t `give’. In new construction, wood framing more or less starts from the ground up; wood members are placed on top …
E (modulus of elasticity) of Wood
The modulus of elasticity (MOE, E) of wood is most commonly used in the calculation of deflections (sag) of wood beams. By `beams’ I include joists, rafters, girders, decking boards, any … wood used structurally to support loads across spans …
Deflections of Wood Beams
When we examine deflections of wood members (beams, joists, rafters, girders, etc.) we generally look at two kinds, actually three … the deflection due to the `live load’, e.g., people walking on a floor, wind on a wall, and so …
Cantilever Post Deflection (Post and Bracket)
Let’s look at a post, say in a shop, or a barn, acting as a vertical cantilever. This means that the base of the post is held rigid (not allowed to rotate), while a lateral (horizontal, or sideways) load is …
`a constantly debated topic’ (pole barn versus post frame)
Pole barn versus post frame … how to keep the structure from flopping over? Consider a barn, or perhaps a shop, made using timber and `posts’. There are two main ways to keep it from flopping over. One way is …
`a constantly debated topic’ (pole barn versus post frame) Read more »
Shear-Free Eeee
E (E and shear-free E) (c) Jeff R. Filler, 2022 The deflections calculated in earlier examples (link and link) are based on the standard engineering formula for beams based on beam-curvature theory – where the beam curvature is a result …