Introduction

 I describe myself as “an evangelistic concrete technologist” suggesting that concrete technology is my religion and I preach it to anyone who will listen to me.

 In pursuance of this attitude I hereby offer to answer free of charge, and without any commercial bias, any question you care to pose to me at kenday@bigpond.net.au. This is a continuance of the free service I have been providing for several years now on the aggregateresearch.com website.

 Obviously there have to be limitations to a free service and some answers may simply disclaim knowledge of the correct answer and some may suggest that more investigation, or a more detailed reply than can be provided without charge, is desirable, but the offer is nevertheless genuine.

 I also offer to provide a more extensive service, initially also at no cost. This is based on analysing your test data. The site now carries completely free downloadable programs for mix design and QC. The mix design may be somewhat outdated but the QC is being actively promoted in USA and elsewhere. A mass of your own data can now be loaded into the QC system in just a few clicks if it is formatted as an XL spreadsheet of the required format, and therefore the system can spring into immediate full use, rather than waiting on the laborious entry of test data sample by sample. A particular aspect of the original version of this program is that it analyses your own data to establish very clearly whether, as I claim, a better prediction of 28day strength is obtained by adding the current average 7 to 28day gain to the 7day result than by anticipating a percentage increase. As an extension to this facility, it is proposed to offer an advisory service based on it. It will be simple for users to email their spreadsheets to myself and for me to prepare a report based on the analysis of those results. At least initially this service will be free. Where extensive service is provided or requested, a charge basis may be agreed at a later date.

A new extension to the site capability is an adaptation of the free QC program to include Air% as this is necessary for US use in particular. This program excludes the feature to compare predictions of 28day strength by adding average gain and by assuming a % increase since it is now obvious that the former is preferable – if you doubt this, the original program is still there and I would be fascinated by data showing my conclusion to be incorrect! The new program also provides the facility to have results analysed by the month of casting.

My objective now (at the age of 80) is to spread my QC techniques worldwide, seeking a place in the history of concrete QC rather than financial gain (however I am still available for paid consultancy if you so desire!).

NOTICE

I consider Multigrade, Multivariable, Cusum Quality Control, as presented in my books and published papers and in the downloadable QC program on this site, to be a fundamental technique or concept, as are such items as Shewhart Charts, Regression Analysis, Statistical Analysis and original Cusum.

I am working to have this technique recognised and included in worldwide Codes of Practice and invite anyone to make use of it. However the ConAd program, as presented in the Screencams on this site, may be legally covered by copyright as it is now owned by Command Alkon, and identical copies should be avoided.