h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Anybody know anything about the use of cement in hot climates - and has some advice and guidance for people using cement in the third world ?

If you are using conventional cements, then there is much work to be done keeping the concrete damp while it cures to avoid excessive shrinkage. The methods are well known and used throughout, for example, Saharan Africa.

As far as the 'Third World' is concerned, then my personal suggestion would be to refer you to the 'Intermediate Technology Development Group' which is easily found on the web, and has much to offer especially in the use of local materials for construction projects. They have a fairly extensive publications list, and you can go on from there to make your own enquiries. The emphasis is on using local materials and methods.

I couldn't find anything in there, the issue is that without a clear approach - which can be easily understood by uneducated people a huge amount of money/effort is wasted because the cement doesn't cure properly.

Are there additatives, how should the cement be kept wet, etc, etc

Thanks for your input the site looks interesting, but nothing specific.

Cement is used to make concrete all round the world. Kuala Lumpar, Singapore, Nairobi, Lagos etc etc are all built using much concrete. The methods are well established. Yes you can use chemicals if you wish, there are many available, but the simplest methods are to use hessian or straw to keep the concrete covered, and keep that covering wet for 28 days, while the concrete cures. In factories they use continuous water sprays, and, if labour is cheap, a man with a hose can do the job perfectly well. If I were you, I would contact some of the cement companies in the country(ies) that you are interested in, or the big International groups (Lafarge, Blue Circle etc.) for more advice.

My personal interest is in a type of cement that doesn't have a curing period, a different approach altogether, but, unfortunately, too expensive for overseas markets.

In some countries you may have local supplies of a good limestone, which can be used to mix with imported coke, bauxite etc. to produce an economic supply of cement. In other places all the ingredients are imported but the cement plant is local and in other places (Nigeris) manufactured cement is imported. It can often be that cement is used in barter/aid agreements, so the economic case for using quite expensive materials is often complex. The same would apply to steel products used in construction.

The Intermediate Technology group take a different, small scale approach, preferring to see use of local traditional materials wherever possible, and thus concentrate on building with lime, clay, mud bricks and so on.