Introduction
See below for a list and brief description of my offerings. These are all made available under the terms of the “GNU General Public License” developed by the Free Software Foundation. A copy of this licence is included as part of the downloads.
The spreadsheets are all written for Microsoft’s Excel. Most require that macros be enabled, and some require that the Solver add-in be activated. Those with macros will run on Gatesian computers but not on Jobsian computers, due to differences in the way VBA is implemented on Macintosh. I have attempted to keep the spreadsheets backwards-compatible as far as Excel 97 (v8.0), but this is increasingly difficult to guarantee. In the “forwards” direction, I am confident they will run under Excel 2019. I have not yet had an opportunity to do any testing with later versions than this.
If you wish to be kept abreast of any changes I might make to these offerings, please e-mail me using the information on the Contact me page. Include in the e-mail the name(s) of the offering(s) you have downloaded.
Index of available items
Non-engineering stuff tends to gravitate to the bottom of the list.
A “template” is also offered (at the very bottom) for anyone who might wish to develop spreadsheets in a similar style.
Analysis of beams on an elastic foundation
Interior of an infinite slab on an elastic foundation
Edge of a semi-infinite slab on an elastic foundation
Analysis of a ‘draped beam’
Loaded cable
Analysis of reinforced concrete cross-section
Dynamics of a two-degree-of-freedom system
Dynamic analysis of machinery foundation
Horizontal Lifeline cable
“Dynamic buckling” of Euler column under short-duration loading
Buckling analysis of a stiffened cylinder under radial pressure
Calculation of solar angles
Extreme value analysis under a changing environment
Simulation of random dynamic pedestrian loadings on a bridge
Multiple regression
Car parking analysis for a residential development
Maximising mixing at a table
Maximising mixing at a multi-session tournament
Holiday cost sharing
Useful features in Excel
“Template” for DIY spreadsheets
Beam on an Elastic Foundation
This program (not spreadsheet) performs an elastic analysis of a continuous beam supported on a continuous elastic foundation. If any part of the beam has an axial compression, the second order effects resulting from that compression (the magnifier, or “P–Delta” effect) will be accounted for. The method used is based on a full rigorous treatment of the problem, and does not rely on any numerical approximations or assumed shape functions. Both the beam and the foundation may have varying stiffnesses. In addition to the support provided by the continuous foundation, the program allows discrete concentrated elastic supports in either the translational or rotational directions. “Lift off” problems, where the beam is allowed to move apart from either its continuous foundation or its concentrated supports, can also be accommodated. The download package includes extensive documentation, demonstration files, and the full Fortran source code (FWIW). The program was developed (intermittently) over more than four decades. The present version is 6·00, uploaded on 02 Sep 2022.
Note that since February 2023 the zipped download package includes the executable file, that should be named BELFAS.EXE, under the name of BELFAS.ZZZ in an attempt to thwart overzealous protection systems. You will need to change the extension of this file back to .EXE before you can run it.
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Interior of an infinite slab on an elastic foundation
This is an Excel spreadsheet that calculates the bending moments and deflection that a set of arbitrarily-shaped pressure loadings produces in the interior of an infinite slab supported on an elastic foundation. The present version is 2·07, uploaded on 11 Jun 2021.
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Edge of a semi-infinite slab on an elastic foundation
This is an Excel spreadsheet that calculates the bending moment and deflection that a set of arbitrarily-shaped pressure loadings produces at the edge of a semi-infinite slab supported on an elastic foundation. The present version is 1·09, uploaded on 11 Jun 2021.
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Analysis of a draped beam
This spreadsheet calculates deflections and bending moments in an infinitely long beam lying on a level ground surface that has a single step in its level. The beam rests on the tip of the step, or (optionally) in a crane’s sling at a location directly above the step’s tip. The beam thus “drapes” across this single support point, lifted off the ground-support for a distance either side, before tangentially resuming its continuous contact with the ground. The present version is 2·00, uploaded on 19 Mar 2024.
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Loaded cable
This spreadsheet calculates the shapes and tensions in a loaded cable running between two end points. The cable can be loaded with a single point load, not necessarily vertical, which can either be attached to a fixed location along the cable’s length or can have a frictionless sliding connection to the cable (such as a running roller). The cable’s end points do not need to be at the same level. The supports for the cable’s end-points can be elastic. The cable can have different properties on either side of the loaded point. The present version is 5·05, uploaded on 19 Jan 2024.
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Analysis of reinforced concrete cross-section
This spreadsheet performs a “plane sections remain plane” analysis of a reinforced concrete cross-section under the combined actions of an axial force and biaxial bending moments. The outline of the concrete cross-section can be completely arbitrary (defined as any polygon). The stress-strain relationships for both the concrete behaviour and the steel behaviour can also be completely arbitrary (defined by piecewise-linear relationships). Prestressing is accommodated, slightly indirectly. The present version is 4·10, uploaded on 19 Jan 2024.
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Dynamics of two-degree-of-freedom system
This spreadsheet performs a rigorous analysis of the dynamics of a linear two-degree-of-freedom structural dynamics problem. It calculates the natural frequencies, and the harmonic response under a set of harmonic loadings. It can also perform a time-history analysis for the system under the combined effects of arbitrary forces and arbitrary foundation movements. The present version is 5·00, uploaded on 26 Jul 2024. This upgrade is important.
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Dynamic analysis of machinery foundation
This spreadsheet performs a vibration analysis of a machinery foundation, using the method described in the book “Design of Structures and Foundations for Vibrating Machines” by S.Arya, M.O’Neill & G.Pincus. The foundation is assumed to be a rigid concrete pad, possibly with some additional concrete blocks rigidly attached to it. This is bearing on the ground, perhaps embedded slightly within it. The foundation is supporting a vibrating machine which is imposing a harmonic loading upon it. The present version is 4·05, uploaded on 11 Jun 2021.
The download package also includes a note identifying some possible errors in chapter 6 of the book “Foundations for Machines: Analysis and Design” by S.Prakash and V.Puri.
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Horizontal Lifeline cable
This spreadsheet calculates the deflection and tension in a horizontal cable that is serving as a lifeline. The cable can be investigated as a static system that is subjected to a “known” (ie code specified) vertical load. Alternatively (or additionally) it can be investigated dynamically where a falling person of known weight falls from a known height, with his fall arrested by the energy takeup in the cable and his harness. As of version 2.00 the dynamic analysis can include energy absorbers. The present version is 2·06, uploaded on 19 Jan 2024.
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“Dynamic buckling” of Euler column under short-duration loading
This spreadsheet models the lateral response of a sinusoidally-imperfect Euler column under the action of an axial compression load that is applied for a short (but not instantaneous) duration. It takes an extremely simplified approach to this complex problem, relying on some very bold assumptions. The present version is 1·06, uploaded on 19 Jan 2024.
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Buckling analysis of a stiffened cylinder
This spreadsheet performs a radial buckling check on a circular cylinder that is stiffened with ring stiffeners. The loading causing the buckling is radially-directed external pressure along with the associated axial loading, plus (optionally) an additional axial compression force. The check is carried out as per the requirements specified in the book “Buckling of steel shells — European design recommendations”, prepared by the European Convention for Constructional Steelwork (ECCS). More specifically, the spreadsheet checks against the rules given in chapter 17 of the fifth edition of the book (published 2008). The present version is 1·06, uploaded on 30 Jul 2024.
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Calculation of Solar Angles
This spreadsheet calculates solar angles (elevation and azimuth) for any place at any time. It also calculates sunrise and sunset times, and can track the shadow of a point onto an arbitrarily oriented plane. The present version is 2·01, uploaded on 13 Aug 2024.
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Extreme value analysis under a changing environment
This spreadsheet 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. The present version is 3·06, uploaded on 30 Jul 2024.
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Dynamic pedestrian loading on bridge
This spreadsheet uses Monte Carlo simulation to explore the dynamic loading a large number of unsynchronised pedestrians are likely to impose on a large pedestrian bridge as they walk randomly across it. It can then take the resulting load-versus-time profile and apply it to a single degree of freedom (SDOF) model of the bridge, to see how the bridge would respond to that loading profile. In particular this second exercise is intended to provide information on whether any peak loading levels are likely to be sustained for long enough that the bridge’s dynamic response will build up. The present version is 2·01, uploaded on 19 Jan 2024.
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Multiple regression
This spreadsheet performs multiple regression on a set of data. In so doing, it provides more comprehensive results than does Excel’s in-built LINEST function. The spreadsheet also incorporates a method for the detection of outliers, but this capability should be used cautiously and sparingly. The present version is 2·04, uploaded on 29 Jul 2024.
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Car parking analysis for a residential development
This spreadsheet performs a Monte‑Carlo simulation analysis into the adequacy of the on‑site car parking provided as part of a residential real estate development. Such developments often provide sufficient car parking only for “average” car ownership levels. Simulation analysis investigates the consequences of statistical fluctuations around any provided level, producing exceedance probabilities for various measures of inadequacy. The present version is 1·09, uploaded on 09 Aug 2024.
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Maximising mixing at a table
The problem that this spreadsheet solves is as follows. A large group of friends organises to get together for a catch-up meal somewhere. They will be seated around a large table, and will only be able to chat FREELY with the people sitting immediately beside them, and AWKWARDLY with the people sitting one seat further away on each side of them. So that they can all catch up with as many of the others as possible it is agreed that they will change seats between courses. But how should the seat-changing be done? A simple rule like “every second person should move four spaces to their right” will work only if the number of diners is a multiple of 4 (and furthermore it doesn’t offer very good mixing). There is no simple rule that can be applied regardless of the number of diners. The approach this spreadsheet uses is a “trial and error” method. For each between-courses mixing it uses random numbers to generate a large series of sets of new seating arrangements, and for each set it evaluates how good the resulting mixing would be. It then selects the arrangement that led to the best result and imposes it. Once this is done it moves on to the next mixing operation and explores another series of possible seating arrangements. The present version is 1·02, uploaded on 30 Jul 2024.
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Maximising mixing during a multi-session tournament
This spreadsheet is intended for the organisers of multi-session tournaments where players compete in small numbers at small tables each session. Between sessions the players change tables so that they play with a different subset of the other players each time. The overall objective is to ensure that no two players are together on the same table more than once, because that maximises the overall player-interactions. The spreadsheet implements a seat allocation method through which this objective is achieved, and it then presents its results in what the author hopes is a useable manner.
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Holiday cost sharing
This spreadsheet has been developed as an aid to maintaining the “accounts” for a group of people travelling together. In such groups expenses tend to be paid at random by group members, and at the end of the holiday (or whenever it is felt necessary) someone has to work out who owes whom what to “balance” the accounts. The balancing task is made more complicated if different expenditure types have to be shared in different ways, such as expenses for alcoholic drinks not being charged to a teetotaller. The task is made even more complicated if multiple currencies are involved. Both of these complications are accommodated by this spreadsheet. The present version is 3·01, uploaded in Octobar 2021.
(These days all of this can probably be achieved much easier using a 99¢ SmartPhone App, but what the heck.)
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Useful features in Excel
This spreadsheet describes and demonstrates some of the lesser-known capabilities of Excel, particularly ones that might be useful in developing spreadsheets for engineering calculations. Obviously the terms lesser-known, useful and engineering will be interpreted differently by different people: hopefully my interpretations will not be vastly different from yours. The present version is 3·00, uploaded in October 2021.
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“Template” for DIY spreadsheets
This download package comprises a “bare bones” spreadsheet built in a similar style to all (most?) of the ones described above. It is intended to give you a “structure” and some simple VBA that provide the same “user interactions” that I try to incorporate into all of my “real” spreadsheets. It also includes a document that describes the general approaches I adopt when developing spreadsheets and the reasons I adopt them. (Yes. I do use my template myself. It saves me a lot of time and tedium.) The present version is 1·03, uploaded on 19 Jan 2024.
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