Site history


This page is intended to help visitors decide whether something of interest to them might have been loaded since their last visit.


12th March 2019:  Released an update (version 11) to the “John Clarke Australian Verse” document.

5th March 2019:  Released a new version (4.04) of the Loaded Cable spreadsheet.  This fixes a wildly incorrect calculation of the “belt & bollard” friction coefficient necessary to prevent sliding.

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.

7th January 2019:  Released an update (version 4.03) to the “Loaded Cable” spreadsheet.  It now includes a RAG (“rough as guts”) method to improve your starting approximate solution before you invoke the Solver to find the true solution.  The spreadsheet also now issues a warning if it is opened on a non-Windows computer.

At the same time I incorporated this non-Windows warning into several other spreadsheets:
      Analysis of reinforced concrete cross-section
      Edge of slab on elastic foundation
      Interior of slab on elastic foundation
      Car parking analysis
      Buckling of stiffened cylinder

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.

August 2018:  Released a minor upgrade to the Loaded Cable spreadsheet (version 4.01).  It now uses a more accurate formula to calculate the stretch along a cable segment.  The change will have no appreciable effect unless the cable is very extensible.

July 2018:  Released a major upgrade to the Loaded Cable spreadsheet (version 4.00).  Responding to user requests I have extended it so that the applied point load can now include a Z component as well as X and Y components.  At the same time, also in response to requests, I have rearranged the work area and added a lot of annotation to it.

April to 2nd May 2018:  Web site was “down”, due to the combined effect of a minor glitch in some software and a major inattentiveness in me.  My apologies to anyone who was inconvenienced.  I’d like to say it won’t happen again, but I’d probably be lying.

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”.

October 2017:  Uploaded a major revision (4.00) of the “Dynamic Analysis of Machinery Foundation” spreadsheet.  Main change is the new ability of the user to choose between (roughly) US units or (roughly) metric units.  Quite a few other improvements were incorporated at the same time.

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.

December 2016:  On about 20th December I was advised by my website hosting service that my site had been maliciously “compromised”, and so had been suspended.  Since that time I have been gradually putting the pieces back together.  I believe that this process has now been completed.

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:  Corrected a minor error in “horizontal lifeline” spreadsheet, where it threw up a host of “divide by zero” errors in its new dynamic analysis worksheet if the value of H was entered as exactly zero.  Embarrassing, eh?

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

January 2016:  The dynamic analysis worksheet of the “horizontal lifeline” spreadsheet was extended to calculate the time duration of the fall and the maximum deceleration force experienced by the falling person.

September 2015:  A new spreadsheet to analyse horizontal lifeline cables was added (as version 1.01).  At the same time a new version of the “Loaded Cable” spreadsheet (version 3.06) was uploaded, reflecting the new-found independence of the “horizontal lifeline” worksheets it had previously contained.

August 2015:  The “Loaded Cable” spreadsheet was updated.  The new version (3.04) corrects an error introduced in version 3.03 two months ago.  In 3.03 I had introduced a cosmetic improvement, but had failed to test that it worked when the worksheets were protected (which they normally would be).

July 2015:  The “Analysis of reinforced concrete cross-section” spreadsheet was updated.  The new version (4.00) uses an improved method for specifying the level of prestress (less cumbersome and more flexible).

June 2015:  The “Loaded Cable” spreadsheet was updated.  A new worksheet has been added, one specifically intended to handle situations where the cable is “over-taut”.

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.

May 2015:  Updated the paper about dynamic loadings on pedestrian bridges.  The only change is the inclusion of the derivation of some of the equations presented in the paper.

May 2015:  Added a spreadsheet demonstrating some useful, lesser-known features in Excel.

Feb 2015:  “Multiple regression” spreadsheet made available for the first time.

Feb 2015:  Site restored after about four days of inaccessibility caused by some glitch somewhere.  Late New Year resolution:  I must remember to check accessibility more frequently.

Sep 2014:  Web site repaired after having been rendered totally inaccessible for about a fortnight.

Jun 2014:  “Analysis of reinforced concrete cross-section” spreadsheet updated.  No computational changes.  Added my original rough working notes to the download package.  Added some extra information on the spreadsheet’s use of protection (on the “Documentation” worksheet).

Nov 2013: 
“Dynamic analysis of machinery foundation” spreadsheet added.
“Private downloads” page created.
Very minor changes made to “Brain function” document.

Oct 2013:  “Buckling analysis of stiffened cylinder” spreadsheet added.

Jun 2013:  “Analysis of reinforced concrete cross-section” spreadsheet added.

Feb 2013: 
This “site history” page created.
“Other sites” page created, and (very thinly) populated.

Jan 2013:  “Dynamics of two degree-of-freedom system” spreadsheet added.

Nov 2012:  Site created.