DIY Builds
Photo by Mehmet Turgut  Kirkgoz Pexels Logo Photo: Mehmet Turgut Kirkgoz

What is the load-bearing capacity of a wood 2x6?

RE: Bearing Strength of 2x6 Bearing stress perpendicular to grain allowable for Doug-Fir is generally about 625 psi, with some factors to modify that. Duration of load factor is not allowed however.

What is the best paint to use on plastic?
What is the best paint to use on plastic?

Use paints that are specifically formulated to adhere to plastics. There are several available on the market such as Krylon Fusion for Plastic® ,...

Read More »
What qualifies as a guest house?
What qualifies as a guest house?

A guest home cannot have a kitchen, and only the most basic bathroom facilities are required. This is because a guesthouse is supposed to be a...

Read More »

Bearing Strength of 2x6 Bearing Strength of 2x6 IFRs (Petroleum) (OP) 13 Jul 05 20:55 I have two pieces of 2x6 Douglas Fir #2 or better, each about 8 feet long. The ends of both pieces are smoothly drilled with a single 9/16" hole to accept a long 1/2" carriage bolt. The bolts go through the 6" way, they is 2 1/2" in from the end of the boards. The two boards are joined with metal plates on their short sides, using the bolts. My question is: what bearing strength or stress should I use when calculating the allowable tension (or compressive) load in this assembly? I guess while I'm asking questions, what would the tensile and compressive allowable stress be for the boards? RE: Bearing Strength of 2x6 Tmoose (Mechanical) 14 Jul 05 12:39 http://w ww.bdg.nus .edu.sg/la bs/structu res/images /beam2.jpg I am not clear on if you building a beam (lateral loading)or a column (axial loading). RE: Bearing Strength of 2x6 SacreBleu (Structural) 14 Jul 05 13:19 Bearing stress perpendicular to grain allowable for Doug-Fir is generally about 625 psi, with some factors to modify that. Duration of load factor is not allowed however. Check out WWPA.org website for more info. RE: Bearing Strength of 2x6 SlideRuleEra (Structural) 14 Jul 05 18:06

https:/ /www.aitc- glulam.org /shopcart/ Pdf/aitc_t n_19_%20ma y_2002.pdf

Discussion starts near the bottom of page 2.

From the "Western Wood Product Use Manual", 2001 Edition, the properties of No. 2 Douglas Fir fall with in the following ranges:

Fv: 180 psi (This value has been corrected per 2001 NDS)

Tension Parallel to Grain: 525 to 575 psi

Compression Perpendicular to Grain: 520 to 620 psi

Compression Parallel to Grain: 1350 psi

E: 1.2 x 10^6 to 1.6 x 10^6 psi

Assuming that your members are beams, American Institute of Timber Construction (AITC) Technical Note 19 address your question directly. Here is a link to this free .pdf documentDiscussion starts near the bottom of page 2.From the "Western Wood Product Use Manual", 2001 Edition, the properties of No. 2 Douglas Fir fall with in the following ranges:Single Member Fb: 850 to 900 psiFv: 180 psi (This value has been corrected per 2001 NDS)Tension Parallel to Grain: 525 to 575 psiCompression Perpendicular to Grain: 520 to 620 psiCompression Parallel to Grain: 1350 psiE: 1.2 x 10^6 to 1.6 x 10^6 psi www.SlideRuleEra.net RE: Bearing Strength of 2x6 IFRs (Petroleum) (OP) 19 Jul 05 22:47 Folks - Thanks for your help. To make sure I am communicating properly, think of this as a splice in the bottom chord of a truss. The lumber is6" vertical, 2" horizontal (nominal). It is a wierd connection - the metal plates are on the 2" sides of the 2x6 (top and bottom) and the bolt is about 7" long, through the end of the 2x6's. The smooth holes are 2 1/2" from the ends of the 2x5's. I can check the metal plates for bearing and tension, and the net section of the 2x6 for tension, and the bolt for shear. I am a little queasy about the 2x6 in bearing. The AITC document is for glu-lam beams, which this is not. The WWPA document does not have allowable or ultimate bearing stresses. The Forest Product Laboratory 1999 Wood Handbook Chapter 7 Fastenings is confusing because it clearly references better research post 1991 but then goes on to discuss allowable loads based on prior work. For instance, it says "Prior to 1991, bearing stress was based on test results at the proportional

Can a garage legally keep your car?
Can a garage legally keep your car?

If you are refusing to pay while you dispute the bill, the garage has the right to keep your vehicle until the debt is paid. If you need the...

Read More »
Does galvanized steel shed rust?
Does galvanized steel shed rust?

When shopping for a storage building, look for a high-quality metal shed that's made of galvanized steel. This material is specifically treated to...

Read More »

limit; since 1991, bearing stress is based on test results at a yield limit state, which is defined as the 5% diameter offset on the load–deformation curve (similar to Fig. 7–3)." However, the following paragraphs, discussion and data are all for "bearing stress at proportional limit load" which was in use prior to 1991. It never discusses yield limit state determined bearing stresses. Any help on bearing stress, or proper edge distsnces? RE: Bearing Strength of 2x6 SlideRuleEra (Structural) 20 Jul 05 11:11 The allowable values for designing with wood are set well below its maximum strength. This is because of the huge variability in how trees grow & and the non-linear performance of (heavily) loaded wooden members. Even the maximum strength, Modulus of Rupture (measured in psi), is a generalized number. For example, here are some values for seasoned Douglas Fir: Maximum Allowable Bending Stress: 900 psi (from reference document in my previous post)

Modulus of Rupture: 12,700 psi (from this link

This logic applies to all the engineering properties of wood.

For the issues on bearing, perhaps this reference, "Wood Structural Design Data" will provide more insight. Look at Page 40, in "Chapter 2A - Wood Beams". Here is a link to the free .pdf download

http://www.awc.org/Standards/wsdd.html

As for how to analyse your situation, I would start with the simplest assumption, i.e. The 2x6 has a full length, uniform crossection of 5 1/2" x 15/16" (1 1/2" true dimension - 9/16" hole diameter)

Do metal sheds suffer with condensation?
Do metal sheds suffer with condensation?

All metal garden sheds will suffer from condensation where damp is present in the foundation. This occurs when a damp proof course has not been...

Read More »
What does CDX stand for in plywood?
What does CDX stand for in plywood?

What is CDX? CDX is veneer plywood, which is manufactured by gluing and pressing together sheets of wood. The letters C and D represent the grades...

Read More »
Can I build my own shed?
Can I build my own shed?

Yes, with the right plans you can build your dream shed.

Learn More »

See what the numbers tell you to determine if you need to "dig deeper". Designing new structures with wood is well defined by NDS requirements. But figuring out what is acceptable and what is not for an existing application is still as much "art" as it is "science".

Best Wishes

IFR - You certainly have a strange situation, I still can't picture the details. Anyway, a few thoughts...The allowable values for designing with wood are set well below its maximum strength. This is because of the huge variability in how trees grow & and the non-linear performance of (heavily) loaded wooden members. Even the maximum strength, Modulus of Rupture (measured in psi), is a generalized number. For example, here are some values for seasoned Douglas Fir:Maximum Allowable Bending Stress: 900 psi (from reference document in my previous post)Modulus of Rupture: 12,700 psi (from this link ht tp://cee.w pi.edu/CE3 026/Lab%20 Data/wood_ table.html This logic applies to all the engineering properties of wood.For the issues on bearing, perhaps this reference, "Wood Structural Design Data" will provide more insight. Look at Page 40, in "Chapter 2A - Wood Beams". Here is a link to the free .pdf downloadAs for how to analyse your situation, I would start with the simplest assumption, i.e.The 2x6 has a full length, uniform crossection of 5 1/2" x 15/16" (1 1/2" true dimension - 9/16" hole diameter)See what the numbers tell you to determine if you need to "dig deeper".Designing new structures with wood is well defined by NDS requirements. But figuring out what is acceptable and what is not for an existing application is still as much "art" as it is "science".Best Wishes www.SlideRuleEra.net Red Flag This Post Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework. Cancel Red Flag Submitted Thank you for helping keep Eng-Tips Forums free from inappropriate posts. The Eng-Tips staff will check this out and take appropriate action. Close Reply To This Thread Posting in the Eng-Tips forums is a member-only feature. Click Here to join Eng-Tips and talk with other members! Already a Member? Login

What to make out of wood that sells?
What to make out of wood that sells?

What handmade wood items sell best? Wooden signs. Wall signs. Wooden pallets. A wooden bench. Kitchen products. Furniture. Surfboards. Boxes. More...

Read More »
How long does it take to season firewood?
How long does it take to season firewood?

Spring is a good time to start seasoning firewood, as it takes at least 6 months to reach optimum dryness. This means if you start in April, you...

Read More »
How do you level ground without a transit?
How do you level ground without a transit?

Find a length of string and two wooden stakes. Tie one end of string to a wooden stake and hammer it into the ground at the highest elevation in...

Read More »
Are shed plans easy to follow?
Are shed plans easy to follow?

These are! They guide you every step of the way to complete your dream shed.

Learn More »
What is the most dimensionally stable wood?
What is the most dimensionally stable wood?

Some of the more dimensionally stable domestic wood species include hard maple, white oak, and white ash. Exotic species are often more...

Read More »