How should cement be stored?
Cement should be kept in a covered area with roof and walls and be free of moisture and water. Cement bags should be tightly stacked in an orderly fashion to prevent air from circulating around them. Moisture must not be allowed to come into contact with cement, and bags of cement should not be placed next to walls to prevent absorption of moisture by this means.
Can sand from the sea be used for construction?
Sea sand contains minerals and salt and should never be used for mixing cement. The salt in particular will cause metal to corrode quickly.
Clean sand means good quality construction
Sand used in construction must be clean and free of dirt such as soil, plants, algae, leaves, shells, or other materials.
Characteristics of stones used in concrete work
Making concrete requires the use of hard stones and gravel, resistant to wear and tear. The surface should be rough and coarse and angled. The stones should vary in size and be free from dirt.
Storing and preserving materials to be mixed with cement
All materials to be used for cement work should be stored neatly, protected from contamination from dirt and moisture. In particular, contact with sweet substances, such as sugar cane pulp, must be avoided.
Cracks made by air conditioners
Air conditioners may cause walls to crack because sudden differences in temperatures between the inside and the outside occur frequently. The way to prevent this problem is to gradually adjust the temperature on the air conditioner by no more than 10 degrees Celsius.
Water and concrete work
Water that is mixed with concrete should be clean, free from oil, salt, acid, alkaline, and various organic substances. Tap water or unsalted clean water from natural sources is best. Salt containing sea water or brackish water because must not be used.
To produce good quality concrete work, attention must be paid to every step
Good concrete work demands: 1. Correct proportions of the mixture. 2. Good materials for the job. 3. Proper techniques and methods, including curing the concrete.
Taking care of the trowel – a an important and versatile tool
The trowel is an important and versatile tool. When not in use it should be kept clean, dry and lightly oiled.
Removing paint stains from cement walls
Sponge away the paint with a cloth, after which floor polish powder and polishing solutions should be carefully applied. If paint stains have been completely dry for over a week, a methylene dichloride solution can be applied and left for 2-3 minutes. The area can then be scraped lightly and rinsed off with water. Floor polish powder may be applied to clean once again.