Site history


This page is intended to help visitors decide whether something of interest to them might have been loaded since their last visit.  (Entries more than a few years old tend to get weeded out.)


23rd March 2021:  Released a new version (3.06) of the “Dynamics of a two-degree-of-freedom system” spreadsheet.  The change in this update is what I hope is a small improvement in the clarity of the graph of the sensitivity analysis.

I also released a new versions of the following spreadsheets, which I have rearranged slightly to that they will print cleanly on both A4 and AQ (“Letter”) paper sizes.
      Edge of slab on an elastic foundation (1.08)
      Parking analysis (1.06)
      Solar angles (1.01)
      Buckling analysis of a stiffened cylinder under radial pressure (1.04)
      Dynamic analysis of machinery foundation (4.04)
      Extreme value analysis under a changing environment (3.04)

17th February 2021:  Inspired by my third burst of Covid-induced lockdown, I developed and released a new version (3.04) of the “Dynamics of a two-degree-of-freedom system” spreadsheet.  The main change in this update is the addition of a capability for sensitivity analysis, allowing the user to explore the effect of varying various defining parameters.  This is a significant addition.

I also released a new version (4.08) of the Loaded Cable spreadsheet, with some minor changes.

11th January 2021:  Released a new version of the “edge of slab on elastic foundation” spreadsheet.  Only significant change is a more detailed discussion of the apparently parabolic deflection contours under the action of a point load at the origin.

7th December 2020:  Released an update (version 15) to the “John Clarke Australian Verse” document.  This update is relatively minor.

4th December 2020:  Released a new version of the “analysis of reinforced concrete cross-section” spreadsheet.  Main change is improved guidance on recalcitrant problems, supplemented by a few cosmetic improvements.

8th November 2020:  Released new versions of the two “slab on elastic foundation” spreadsheets, adding to each the ability for the footprint graph to show the areas of the slabs where loadings can have a significant influence.
      Edge of slab on elastic foundation, now version 1.06
      Interior of slab on elastic foundation, now version 2.06

21st October 2020:  Released new versions of the two “slab on elastic foundation” spreadsheets, adding to each the ability to rotate individually the predefined load shapes.
      Edge of slab on elastic foundation, now version 1.05
      Interior of slab on elastic foundation, now version 2.05

18th September 2020:  Released a new version (4.07) of the “Loaded Cable” spreadsheet.  The main change in this update is a correction to the calculation of “belt & bollard” friction.  Earlier versions calculated this in a NON-CONSERVATIVE way for cables that had a significant out-of-plane force component.

9th July 2020:  Released a new version (3.03) of the “Dynamics of a two-degree-of-freedom system” spreadsheet.  The main change in this update is the addition of a phasor diagram.

22nd May 2020:  Added CESDb to the “Other sites” page.

16th March 2020:  Released a new version (1.04) of the “Dynamic Buckling” spreadsheet.  The main change in this update is the inclusion of an alternative force-time pulse shape.

6th March 2020:  Released a new version (1.03) of the “Dynamic Buckling” spreadsheet.  The main change in this update is the inclusion of the results of a verification exercise that used finite element analysis.

15th February 2020:  Released a new version (4.06) of the “Loaded Cable” spreadsheet.  The only change in this update is to make it possible, under user control, to analyse cables that are extremely slack or extremely extensible.

5th February 2020:  Released a new version (4.03) of the “Dynamic Analysis of Machinery Foundation” spreadsheet.  The main changes in this update reflect more informative documentation of the Coupled Analysis capability.

22nd July 2019:  Released a new spreadsheet that calculates solar angles.

25th February 2019:  Released a new spreadsheet that maximises the mixing among a group of people seated around a single table enjoying a multi-course meal.  Between each course, they should change seats as per the plan this spreadsheet produces.

25th October 2018:  Released new versions of nearly all the engineering spreadsheets.  This was triggered by the discovery of a very infrequent, possibly machine dependent, VBA error that occurs when the spreadsheet is opened.  The problem seems to be related to code attempting to be executed before the page is ready, particularly when the spreadsheet opens in protected mode.  I believe that the updated versions get around the problem, but cannot guarantee this.  If you haven’t hit the problem you probably don’t need to download these new versions.  But why not play safe and do it while you are here?

24th October 2018:  Released a new spreadsheet.  This one calculates the probabilities of an environmental “extreme event” occurring during the expected life of a project when the underlying “environmental regime” that throws up these events is changing with the passage of time.

October 2017:  Uploaded an attempt to identify the poets and poems being parodied by John Clarke in his brilliant book “The Even More Complete Book of Australian Verse”.

August 2017:  Uploaded a new version (1.02) of the Parking Analysis spreadsheet.  Main change was trapping an error that would occur if the user analysed a development containing dwelling sizes for which no population statistics were available.

April 2017:  Added a new spreadsheet that uses Monte‑Carlo simulation to investigate the adequacy (or otherwise) of the on‑site car parking provided by a residential real estate development.

August 2016:  Added a new spreadsheet to investigate (very crudely) the “dynamic buckling” of an Euler column subjected to a short-duration axial compression.

June 2016:  The dynamic analysis worksheet of the “horizontal lifeline” spreadsheet was comprehensively reworked to allow the inclusion of “energy absorbers” in the analysis.

May 2015:  I have at last had an opportunity to check my spreadsheets under Excel 2013.  The checking was relatively superficial, but it suggests that none of them have any problems.

Nov 2012:  Site created.