| I have been involved with many thousands of tons of concrete building bridges, roads, sidewalks, light pole foundations, etc etc. I have never heard of concrete not setting after 3 weeks or anything like that. Contractors sometimes have retarders added which delays the chemical reaction, giving them more time to work on bigger pours. Even with way too much water it will usually set within a matter of hours, definitely not weeks. They either left out most of the cement or mistakenly put a chemical retarder into the quickcrete. It is said that adding sugar to fresh concrete will delay set but I've never tried it, and it would be sabotage in your case. Concrete even sets under water. |