Why is initial setting time necessary?

Initial setting time is the time when the paste starts losing its plasticity. Initial setting time test is important for transportation, placing and compaction of cement concrete. Initial setting time duration is required to delay the process of hydration or hardening.

Is standard consistency 4031?

STANDARD • IS: 4031 (Part 4) 1988 DEFINITION • The standard consistency of a cement paste is defined as that consistency which will permit the vicat plunger to penetrate to a point 5 to 7mm from the bottom of the vicat mould. Fill the vicat mould with this paste resting upon a non-porous plate.

Why normal or standard consistency of cement varies?

Why normal or standard consistency of cement varies? Normal or standard cement consistency varies because of weather conditions, temperature, humidity, excessive composition of silica in cement, fineness of cement and we know that cement are provided and made by different companies have some different consistency.

What is the amount of water used to conduct the initial setting time test of cement which has a standard consistency of P?

0.85P
For setting time test, the water quantity=0.85P; where P=amount of water required for standard consistency. Water quantity required for soundness test=0.78P and for compression strength test is “(P/4+0.3)” combined mass of cement and sand.

What is the initial setting time Mcq?

What is the initial setting time? Explanation: The time at which cement paste loses its plasticity is known as initial setting time of the concrete. Explanation: As per IS specification, the minimum initial setting time is 30 minutes for ordinary portland cement.

Is 4031 initial setting time?

The period elapsing between the time when water is added to the cement and the time at which the needle fails to pierce the test block to a point 5.0 ±0.5 mm measured from the bottom of the mould shall be the initial setting time.

What do you mean by initial setting time of cement?

Initial setting time of cement is defined as the time elapsed between the moments when water is added to the cement to the time when the cement paste starts losing its plasticity.

Why do we need a standard consistency test?

1. Why do we need Standard Consistency Test? Explanation: This test is performed to determine the quantity of water required to produce a cement paste of standard or normal consistency.

Why the test of standard normal consistency of cement is important?

Finding out standard consistency of cement is essential because the amount of water added in cement affect the setting time of cement, Less water added than this standard consistency would not complete chemical reaction thus resulting in the reduction concrete of strength and more water would increase water-cement …

What is the initial setting time to answer single choice?

30 minutes
Explanation: As per IS code 4031-part 5, the initial setting time of cement is minimum of 30 minutes. After this cement will start losing its plasticity and will not be workable.

What is meant by initial setting time?

What is the meaning of initial setting time test?

Indirectly related to the initial chemical reaction of cement with water to form aluminum-silicate compound. Initial setting time is the time when the paste starts losing its plasticity. Initial setting time test is important for transportation, placing and compaction of cement concrete.

What is the water content required for setting time of cement?

The standard IS 4031 :1988 (Part V) requires the water content to be gauged for determining the setting time of cement by Vicat’s Apparatus to be 0.85 P (wherein P is the Percentage of water required to attain Normal Consistency of the said Cement. Let us now take a look at what is considered in other International Codes before we form an opinion.

How do you test the setting time of cement?

Before commencing setting time test, do the consistency test to obtain the water required to give the paste normal consistency (P). Take 400 g of cement and prepare a neat cement paste with 0.85P of water by weight of cement. Gauge time is kept between 3 to 5 minutes.

What is the minimum amount of water required for hydraulic cement test?

According to ASTM C191, for “Standard Test Method for Time of Setting of Hydraulic Cement by Vicat Needle” the water required is of the same percentage as that is of Normal Consistency of Cement.