Changes

Concrete production and drought

No change in size, 23:23, 4 June 2012

→‎Construction, operations and maintenance

* Type of water used should be as pure as possible.

* Don’t use weathered rock for concrete aggregate. For the best concrete it is best to use a fresh rock aggregate such as crushedgranite of gneiss or well-washed river gravel. With the latter the river has removed the weak pieces.

* Use clean gravel – impurities will weaken the concrete.

* Use aggregate (gravel) of 5-20mm for non-porous concrete and 5-10mm for porous concrete. Aggregate can be graded using 2 locally-made sieves of 5mm and 20mm – discard any aggregate that remains on the 20mm sieve or that falls through the 5mm sieve.The reasons for having a maximum size is to do with workability, but also that the maximum size is not greater than the “cover” of

concrete over a reinforcing bar – if a stone would span the distance from outer edge to reinforcement, this can become a zone of

weathering where water can get in to corrode the reinforcement.

• ← Older edit
• Newer edit →

Winona

Akvopedia-spade, akvouser, bureaucrat, emailconfirmed, staff, susana-working-group-1, susana-working-group-10, susana-working-group-11, susana-working-group-12, susana-working-group-2, susana-working-group-3, susana-working-group-4, susana-working-group-5, susana-working-group-6, susana-working-group-7, susana-working-group-8, susana-working-group-9, susana-working-group-susana-member, administrator, widget editor

30,949

edits