Drawing Reinforcement in Excel…Really (Part 3)

In Part 2 we covered the functions for creating coordinates for accurately representing shear reinforcement (stirrups and links) using an XY scatter chart in Excel. In this third and final part, we’ll cover the functions for outputting the minimum lengths of stirrups or links. As mentioned in the first part in this series, estimating the total length of bars and hence weights can be a tedious boring process. These functions take out boring bits, but it’s still not ‘exciting’.

Drawing Reinforcement in Excel…Really (Part 1)

One thing that irks me about a lot of spreadsheets I’ve seen created over the years is the fact that the inputs for something that can be visualised are hidden behind a few numbers in cells. No visual representations of the calculations are given. With an overarching reliance on the user to mentally complete the picture of their design inputs (and sometimes outputs) within their minds.

To minimum or not to minimum, that is the question?

Minimum steel, love it or hate it, we have minimums for a reason even if it seems like overkill sometimes given that we may have very low demands. This post will demonstrate why (I hope) we are required to comply with these arbitrary limits. Usually I’m going into these posts with only the theoretical background of why something exists, but hopefully once we get into it this theory can actually be demonstrated.

Using Mathematica to save the world

Well, one person’s world of torsion anyway… In this post I’ll show how to use Mathematica to check some derivatives of torsion relationships. Mathematica is an analysis/computational tool by Wolfram. Now if you had to pony up the dollars for it you’d be out a few thousand dollars, but as it happens I’m cheap and it’s free on Raspberry Pi’s Raspbian operating system. Yes it’s linux based, but don’t let that turn you off, it’s so simple to setup anyone…

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.