The correct spelling is cement (concrete, glue, or verb to firmly join).
Water does not become concrete at any height. Concrete is a solid material made from a mixture of cement, water, and aggregates like sand and gravel.
Stone and sand.
Water does not solidify into concrete at any specific height. Concrete is a mixture of cement, water, and aggregates that hardens through a chemical process called hydration.
Well, if you have a ratio of cement, water and sand that is about 1:1:2, it can make it stronger. However, add any more sand to that, and the concrete can become brittle, making it weak and easy to break.
Small amounts of concrete can be easily mixed in a wheelbarrow with a spade but larger amounts might require a concrete mixer. Towable concrete mixers, both electrical and mechanical (petrol) can be hired from hire plant depots. Mix in the wheelbarrow or concrete mixer, cement, gravel, sand and water. For general purpose concrete the mix can be 1 part cement, 2 parts sand and 3 parts gravel. Most cement bags will have mixture recommendations written on the bags. The mixture of cement, sand and water is going to vary depending on the planned use of the surface.
It depends on the grade of the concrete which typically depends on cement strength, aggregate interlocking and even any chemical bonding agents...
Normal Concrete refers to the fresh concrete which haven't yet cured providing that there was no add mixtures/any accelerators being infused upon mixing fine aggregates, gravel and cement plus water.
Mold does not come from the concrete, it comes from mold spores that are normally in the air. Dampness faciliitate the growth of mold which comes in contact with concrete or any other material allowing mold to grow.
To effectively use hydraulic cement to fill cracks in concrete walls, first clean the crack thoroughly and remove any loose debris. Mix the hydraulic cement according to the manufacturer's instructions and apply it to the crack using a trowel or putty knife. Press the cement firmly into the crack and smooth the surface. Allow the cement to cure completely before painting or sealing the wall.
Generally, salt is harmful to concrete. It will seriously corrode any reinforcing steel. The salt crystals, when the concrete is dry, will weaken the concrete. The setting of cement is a complex set of chemicals, calcium sulphates and silicates mainly. The presence of salt may interfere with these crystals forming, which may take years.
If you are talking about shrinkage, then quite a bit. To make concrete, cement and water react together. There is a specific amount of water required to hydrate the concrete. Any water extra must leave the concrete and while it makes the concrete more workable, hurts the concrete is several ways. The volume of the concrete will change by whatever excess water you have added. To get workability, it's always best to use a water reducing admixture.