TOP 3 ways to use hardened cement for household needs
Old cement is not a death sentence. It can still be put into action. There are at least 3 options for using it.
How to use old cement
When we talk about old cement, we most often mean cement that has turned into stone. At first glance, it seems hopeless. It’s not that you can’t mix the solution with it, but it’s even difficult to take it to a landfill. Sometimes there is advice to crush petrified cement into dust and use it for its intended purpose. Unfortunately, such advice has little in common with reality.
A substance as hard as stone is no longer cement.
Under the influence of moisture and carbon dioxide, a chemical reaction of hydration occurs in the open bag. Roughly speaking, the material uses up its astringent force and turns into ballast or cement stone.
When breaking and grinding cement stone, the binding properties do not return.
This is provided that it can be broken down and turned into a homogeneous powder. This is very difficult to do. The stone is heavy and hard. You can't do it without a sledgehammer. She will have to work for hours, surrounded by a column of dust.
Everyone who has tried to grind cement stone is unanimous in the opinion that this is “Sisyphean labor” (painful, fruitless work).
concrete aggregate
Still, there is no need to rush to get rid of petrified cement. As is known, aggregates in concrete mixtures can occupy up to 80% of the volume. They help reduce the consumption of binders and create the necessary rigidity.Cement stone can serve as a filler.
Break the stone into fractions using a hammer and chisel. Mix the resulting crushed stone in a ratio of 1 to 3 with gravel, broken tiles, and other construction waste.
Concrete aggregate is useful in the construction of formwork and pouring foundations “on the ground”. In the first case, fractions of 5-20 are used, in the second, 20-40.
Pillow
Crushed petrified cement is useful when laying paving slabs, pouring floor screed, concrete paths, and installing curb stones. All such designs need a pillow. It allows you to reduce shrinkage, level the bottom of the recess, reduce point pressure and drain water. Also, the pillow will not allow plants that “sleep” in deep layers of soil to germinate.
Mix 2 parts cement crushed stone and 4 parts gravel (crushed stone). Pour onto a layer of sand. Make a sand mound on top.
Pillows are carefully compacted and can consist of different components. A clear example of how to make a cushion for paving slabs:
Small works: posts, patches, decorative structures
The third way to use old cement assumes that it has not petrified, but simply caked. In this case, the material will easily return to its free-flowing state.
Roll the bag on the floor for 2-5 minutes. If the shell has holes, you can pre-wrap it in film.
If hydration does not occur, the flowability of the cement will quickly recover. It happens that he is partially petrified. In this case, you can use a sieve to separate the cement from the stone.
Old cement is less durable than new cement. After the expiration date, it loses approximately 15% of the brand every month. For example, 500 cement (even crumbly) will become 200 after a year of storage.
Naturally, it is better not to use it in the construction of serious buildings (brick laying, foundation for a house). But for small jobs, the building material is quite suitable. With it you can:
- make posts in the garden;
- fill the garden path;
- fill the area for drying clothes;
- make decorative flowerpots, sculptures for the garden, etc.
Mix old cement with fresh cement in a ratio of 1 to 1. This will increase its grade.
Questions and answers
Question: How long can cement be stored?
Answer: Cement has a short shelf life - 45 days for quick-hardening and 60 days for other types. In this case, the countdown is carried out not from the date of purchase, but from the moment of shipment from the manufacturer.
Question: How to preserve cement until the next construction season?
Answer: Wrap in plastic or pour into sealed plastic barrels, and wrap the neck with film. The storage location should be dry and relatively warm: pantry, dry shed, garage, summer kitchen. It is also recommended to place the bag not on the floor, but on a pallet or other elevation. If all conditions are met, the material can be stored for 1-1.5 years or more. But no one can guarantee its activity.
There is no need to throw away old cement. It can continue to be used after many years. True, not for its intended purpose. The fossilized material makes excellent crushed stone for filling concrete, a cushion for various structures and structures. And while maintaining its flowability, it can be used in small jobs!