William S. Godfrey- S.E.
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How does width and thickness affect the stiffness of steel plate?
15 votes

The stiffness of a rectangular cross section, be it steel, concrete, wood, or any other material, is related almost entirely to it's modulus of elasticity, $E$, and it's moment of inertia about the ...

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Wood roof specs on engineering drawing
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7 votes

I am a practicing structural engineer with plenty of wood experience. That said, this is a bit of a tricky note because I believe it was probably written by an architect on a set of architectural ...

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How to derive Equivalent Static Load for irregular structure modeled with FEM?
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7 votes

The short answer to your question, How can we compute the Equivalent Static Lateral Forces, the overturning moment and other quantities in an irregular building/structural discretized by finite ...

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Effects of constructed tubular/annular beam upon moment of inertia
7 votes

Moment of inertia is not a material property, it is a geometric property. Regardless of the material you are dealing with, a member that is 2" wide by 10" tall in cross section has the same moment of ...

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What does it mean when actual member reaction is 100% of allowed?
6 votes

This means that the member is considered to be fully loaded for a failure mode which is being analyzed by that stress calculation. Some things to (probably) keep in mind include: Some conservatism ...

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Accidental Torsion and Equivalent Static Load for an irregular structure
6 votes

How should we obtain $F_x$, given that it is lateral static force, but we are doing dynamic analysis? $F_x$ is the sum of the lateral force for a story. If you've performed a dynamic analysis, ...

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ASCE 7-10 Wind Loading with roof overhangs
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6 votes

I believe you are correct, the diagram in your book is incorrect in the way it has labeled Zones F and G. This is a bit of a stretch, but I think this may be related to/as a result of an error in ...

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Basic Hook development length using CSA A23.3 provisions
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3 votes

I'd agree, you cannot fit a horizontally oriented 5" 90° bar bend in an 8" thick wall if you want your rebar curtain to be located at the center-line of the wall. However, there is no reason that the ...

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What is the correct term for long cuts in a floor joist?
3 votes

In my experience, this is called a rip. I've seen it done a lot (on the top of a beam section) to accommodate flooring thicknesses/slopes. Your reference actually mentions this, although briefly, on ...

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Find location of resultant of forces without using moments
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3 votes

Method to Solve the Problem This problem requires only 2 things: one must remember that a force applied to a rigid body may be considered to act on the body anywhere along its line of action, and ...

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Design behind typical keyed construction joints in concrete walls
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3 votes

Typically one does not consider the key when checking a slab - footing interface. This is based on ACI318 Section 15.8.1.4, which discusses the transfer of lateral forces to footings and directs the ...

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How is biaxial bending considered for reinforced masonry design?
2 votes

I think that the MSJC (ACI530) actually contradicts itself, a little, with regard to biaxial bending of reinforced masonry. As you pointed out, Section 2.2.3 (unreinforced masonry) points to the use ...

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For a column, what does "rotation fixed and translation fixed" mean
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2 votes

So there's a permutation of rotation and translation each being either fixed or free for a column. What do each mean? To say that a specific degree of freedom of a support is "fixed" is to say that ...

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How to calculate the relative contribution of each mode in seismic dynamic mode analysis?
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2 votes

You should be normalizing your eigenvector so that the generalized mass matrix (defined by $ \hat{m} = \phi^T M \phi$) is the identity matrix, and therefore, the generalized mass of the rth mode (...

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What is the unbraced length of the compression portion of an X brace?
1 votes

The second edition of the AISC Sesimic Design Manual (SDM) contains many wonderfully worked out example problems. I highly recommend that you purchase this resource if you are designing braced frames ...

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