Rational Buckling Analyses to AS4100 or NZS3404 (Part 5)

So if you’ve been following along with this series you now hopefully know a little bit more about some of the methods involved in undertaking buckling analyses. Pat yourself on the back for making it this far through my ramblings I guess (if nothing else). It’s pretty simple, and in most cases it will yield a capacity very similar to the code hand methods, albeit via a completely different path. It’s always good when different methods yield similar results.

Rational Buckling Analyses to AS4100 or NZS3404 (Part 3)

In the last post in this series we looked at a semi-real scenario where a rational elastic buckling analysis was undertaken in which we were able to determine the axial capacity of a system of members. The exact type of system of columns is sometimes referred to as a ‘lean-on’ system, whereby the column carrying no load helps to increase the capacity of the supported column. Basically, if we make the supporting column (or in other words the bracing system…

Rational Buckling Analyses to AS4100 or NZS3404 (Part 2)

In part 1 of this series, we briefly explored the requirements related to calculating the capacity of a column via the use of a buckling analysis. Introducing the general methodology to follow and showing agreement with the normal hand methods for a known effective length factor. In this follow-up post we look at the power and beauty of this method in being able to assess any complicated design scenario, typically ones that don’t fit in the mould of the typical…

Rational Buckling Analyses to AS4100 or NZS3404 (Part 1)

This post was inspired by a rather epic post at Eng-Tips forum, which came out of a seemingly simple request for some help on the segment length to consider for a continuous beam design to AS4100 (the Australian Steel code). Fast forward several hundred posts of debating issues of code interpretation, debates over critical flange definitions, everyone telling each other everyone else is wrong, backtracking, changing of minds, notionally proposing re-writing code clauses to suit particular sides of the argument,…

Inflection point != point of restraint

It’s a question that seems to come up from time to time in my experience, can you take the point of inflection as a point of lateral restraint for the restraint of structural steel members under flexural forces? The answer is of course… NO! Let me say that again… NO, NO, NO! Some people don’t ask obviously before doing, they just do it and are none the wiser.

Improving Excels spellchecker with highlighting

Excel does many things well, but it goes without saying many things could be vastly improved, or at the very least shown a bit of love by Microsoft. One particular thing in Excel that that causes me some frustration is Excels inbuilt spellchecker. Why? Because it’s infinitely more shit than the spellchecker in any of the other office products for a start. This personal view is primarily born out of using Excel for the purposes of recording text based queries…

Parabolas, Rectangles, Triangles & Snakes (Part 9)

Part 9 – Verification Part of the verification process in development of a spreadsheet or software tool involves what I like to term the process of idiot proofing. Some end users are considered as potential idiots, asking yourself to think like this idiot can be a challenge, as it doesn’t come naturally to some. Luckily as engineers we are good at solving problems, identifying risk and considering all eventualities, and are able to either test for these eventualities or provide…

Finding an equation for the Moment of Inertia of a complex tapering member using Python

Often in engineering you need to make simplification in analyses that make your life easier, often applying some judgement based on experience that involves some simplification in the analysis of a structure for example. Sometimes you do this in the name of achieving conservatism, other times to get a reasonable/faster answer that is deemed close enough to the true solution to be accepted as good enough. Sometimes peoples understanding of engineering principles lets them down here, and the end result…

Finding the Warping Constant for back-to-back Cold Formed Channels using Python

This blog post is inspired by a recent post which I responded to on the EngTips forum. The question was related to finding the warping constant of back to back cold formed channels. The poster was querying the validity of some random formula for calculating the warping constant for back to back channels that they found in another post. Comparing this to values that were published for the shape they were interested in, and they were ultimately getting limited agreement.

The Ruskies are coming?

When setting up the WordPress software on which this blog runs, I wanted it to be secure, who wouldn’t. I mean nothing can be guaranteed as being 100% secure, but we can certainly do our best to address known weaknesses and harden the installation of WordPress and the underlying web server.

Parabolas, Rectangles, Triangles & Snakes (Part 8)

Part 8 – Documentation, the Necessary Evil Love it or hate it, I’ve already decided documentation is required so you are stuck with it. Code comments and docstrings aside, part of the planned documentation is this series of blog posts (so I can remember what I did basically). Hopefully these demystifying some of the mysteries behind the general methods involved. For the remainder I’ll leave it up to a readthedocs page to explain the ins and outs for the end…

Parabolas, Rectangles, Triangles & Snakes (Part 7)

Part 7 – Documentation & Verification, Better Than More Integration? At some point in any projects life cycle you should start thinking about the need for documentation and verification. This post and probably the next few will be dedicated to exploring these aspects. As a structural engineer, if you are designing a building you have to produce some drawings, calculations, specifications, etc to describe what is being built, and someone probably needs to check these deliverables. Often the drawings are…

Pi Massacre

This site is hosted on a Raspberry Pi 3, I like to tinker with these things. I don’t use this particular Raspberry Pi for anything else but the WordPress server on which this site runs for fear of breaking it. However, I usually update/upgrade the underlying operating system on a regular basis to ensure it’s running the latest and greatest fixes for peace of mind. This includes runningsudo rpi-update to update the firmware to the latest and greatest. Today I…

Parabolas, Rectangles, Triangles & Snakes (Part 6)

Part 6 – Slicing & Dicing Based on the last two posts, I’d now reached the stage where I’d determined the general basis for calculating the force and centroid of the concrete compression force. This seemed like one of the major challenges had been overcome, just a matter of coding it now I guess. Going Off Script… However for a moment I’d like to touch on the inherent errors in other approaches, because you’re probably thinking all this integration is…