What should we take before placing concrete?
To avoid sticking of concrete, formwork should be oiled before concreting. While placing concrete, the position of formwork and reinforcement should not get disturbed. To avoid segregation, concrete should not be dropped from a height more than 1 meter. Concrete should not be placed during rain.
What precautions are to be taken before during and after concreting?
Precautions Before, During & After Concreting: If possible, mixer machine should be installed below the shade. 3. If concrete is to be transported to a longer distance, concreting materials may be mixed first in dry condition and the water may be included at the job site just before placing the concrete in position. 4.
What are concrete factors?
Concrete strength is affected by many factors, such as quality of raw materials, water/cement ratio, coarse/fine aggregate ratio, age of concrete, compaction of concrete, temperature, relative humidity and curing of concrete.
What precautions should be taken during mixing and casting concrete?
Mixed materials must be laid at the required site within 30 minutes after adding water to the cement. Care should be taken that in any case the mixed materials should not be dropped from a height greater than 1.2 meter in order to prevent segregation of coarse aggregate and mortar.
What precautions you will take before placing concrete in hot weather?
Precautions in hot weather concrete pouring:
- Schedule concreting.
- Material and mix proportions: use material and mix design proportion having good weather resistance e.g. select sand having low specific heat.
- Covered environment: The concrete can be done in a covered environment.
What are factors affecting workability of concrete?
Factors which affect workability of concrete are:
- Cement content of concrete.
- Water content of concrete.
- Mix proportions of concrete.
- Size of aggregates.
- Shape of aggregates.
- Grading of aggregates.
- Surface texture of aggregates.
- Use of admixtures in concrete.
What is the main factor that determines the strength of concrete?
The ratio of the weight of water to the weight of cement is called Water/Cement ratio. It is the most important factor for gaining the strength of concrete. The lower w/c ratio leads the higher strength of concrete. Generally, the water/cement ratio of 0.45 to 0.60 is used.
What is pre concreting checking?
Before the concrete is poured into the formwork, it must be checked by someone who has been trained to inspect formwork. Exceeding this limit may lead to unacceptable formwork deflections, loss of grout / concrete at joints, or even collapse. …
What is concrete placing?
Definition: the deposition, distribution, and consolidation of freshly mixed concrete in the place where it is to harden (often inappropriately referred to as pouring).- ACI Concrete Terminology.
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