Testing 6x6 treated posts vs 2x6 laminated posts at DDS engineering part 1

Today we took a trip to DDS engineering to test out some posts that we built. We tested the strength of a laminated post made of three 2x6’s that were glued and nailed together versus a 6x6 treated post. We’ve got to admit, we didn’t accomplish everything we wanted to today. We are going to make some changes to the machine used for testing, and revisit this in a week or two. A huge thank you to Matt and Alex at DDS for making this all happen. Stay tuned for part 2!

[povleo]

Good video, we need more. Not many on the internet showing wood strength testing. A very common and necessary practice is drilling holes in posts say up to 1" in diameter. We need to know how is strength affected when holes are drilled for bolts, etc. You could test different sized holes in a 6x6 and holes spaced at different lengths apart. Furthermore, holes that cross each other creating a hollow X and the same crossed holes but spaced apart so they don't create the hollow X. A video like that will offer so much insight to the building world.

[TeslaBoy]

Interesting test very important to know 👍👍

[richardvigrass]

Thank you for sharing the video on testing the posts. Very interesting tests. Hope to learn from your tests and some practical applications of your results.

[kurtsmith]

Your testing 2 different types of wood, the lighter colored laminated beam is spruce, the 6x6 is PT yellow pine. Also a 2x6 triple laminated is 4.5inx5.5in whereas a 6x6 is actually 5.5x5.5. In theory a laminated beam should be stronger as it minimizes weak points from knots & grain run out as well as allows you to build a straighter post. If you were testing a fairly clear 6x6 w/ no knots, the test would probably be fairly close.

[redsquirrelftw]

That was cool, but for something like a beam I would have liked to see a more dedicated machine, where you can have it sit on two mounts like 16' or more apart and then have a much larger stroke cylinder push down in the middle and watch deflection based on different weights. Would be a more real world test. I want to design my own floor trusses and it's hard to find info online on how to actually engineer it properly so I will probably end up experimenting with different designs then test them. I'm thinking I would build two units and have IBC totes sitting on both in the middle and then fill them with water. I can probably figure out the weight based on how much water I managed to put inside. In my case I would end the test once it has started to show any signs of early failure or too much deflection.

[B-Shep]

Well, I am up late Googling random things and decided to Google laminated posts, not sure why. lol I came across this video and heard you mention Bowling Green Ky, well I'm just up the road from you around Taylor/Adair area. Love this video!! Have you made part 2 yet? If so i might have overlooked it.

[WFKO.]

i don´t see the point. where you see this situation on construction where force is applied on 50 cm beam that is supported on both sides? longer beams are weaker anyway. if you apply force middle of it.

[SixStrings]

The short length and stroke seems deceptive and how does this relate to span between support point and load. You still have twist . Interesting test

[bruceking]

add length to your test boards and you can use less weight to failure for horizontal or vertical elements.

[charlesdefrancisco]

Great subject but agonizing to watch waiting and waiting for something

[bobsutube]

I'm confused - there was no loading of a post in the axial direction in this video. Just a beam type loading. I don't see a part 2 anywhere

[Pete]

Why in the world would there be a kid in a Testing Lab within 10 ft of a machine

[MeanderLife]

Not sure why you decided to test in an orientation that is never used... In a way you are testing "span" or "lateral" strength perpendicular to "end-to-end". "posts" are never used for "joists" or "beams" to span distances... "Posts" are used for "Posts"... you know, like the name...
Compressive strength (load end-to-end) would seem more appropriate? As the materials are used in this method...
I HAVE seen now where post & beam or "pole" buildings are using triple 2x6 laminated members in place of a "mono" 6x6 post because of "reduced cost" and less deformation / twisting as they dry/cure.
A much more relevant question is... "do they separate along laminations under compressive load, compared to solid post"... or "does the dissimilar wood grain of 3 boards support more load when bonded together"...

[Freetheworldnow]

You should not have published this video.