Skip to main content

Physical Test of Cement to know Its Quality


Cement is the most common and important material in civil construction, so everyone involved in the construction field must carry basic knowledge about the test performed on cement. In this post, I'll discuss some basic tests of cement.

The physical tests which are generally performed to determine the acceptability of cement are –
  1. Fineness Test
  2. Consistency Test
  3. Setting time Test
  4. Soundness Test
  5. Strength Test
  6. Heat of Hydration Test
  7. Specific Gravity Test

1. Fineness Test
Fineness is the mean size of cement grain. It is done to measure the mean size of cement grain.
The finer the cement the surface area for hydration will be large and it increases the strength of cement. But the fineness varies in different types of cement.
One of the following three methods can be applied to test the fineness of cement-
  • Sieve method
  • Air Permeability method
  • Sedimentation method
2. Consistency Test
This physical test of cement is done to estimate the required water quantity to form a normal consistency cement paste. It is defined as the percentage of water required form the cement paste.
3. Setting Time Test
Cement has two types of setting time – Initial setting time and Final setting time.
Initial setting time is the state of cement mortar or concrete when it starts to become stiffen and unworkable.
Final setting time is the state when cement mortar or concrete has become fully unworkable.
Two methods are used to find the initial and final setting time of cement
  • Vicat needle method, and
  • Gillmore needle method
4. Soundness Test
The soundness of cement means it doesn’t undergo large volume change after setting. Large changes in volume produce cracks, disintegration, and distortion, ultimately leading to failure. So it is very important to test the soundness of cement.
To test the soundness two methods can be applied.
  • Le-Chatelier method
  • Autoclave method
5. Strength Test
Cement has two types of strength – compressive strength and tensile strength.
To know the compressive strength and the tensile strength of cement following tests are performed –
  • Cement mortar cube test (for compressive strength)
  • Briquette test (for tensile strength)
  • Split tensile test (for tensile strength)
6. Heat of Hydration Test
Cement produces a large amount of heat during the hydration process. When a large amount of concrete volume is poured the inner temperature is greater than the outer surface of the concrete. Because the outer surface is exposed to the weather. Thus the outer surface shrinks rapidly than the inner surface and tends to produce cracks. That is why it is important to test the heat of hydration of cement.
Following test is performed to know the heat of hydration of cement
  • Calorimeter method
. Specific Gravity Test
The specific gravity of cement is a comparison of the weight of a cement volume to the weight of the same volume of water.
Le-Chaterlier flask is used to test the specific gravity of cement.







Comments

Post a Comment

Popular posts from this blog

CORROSION OF REINFORCEMENT IN CONCRETE

CORROSION OF REINFORCEMENT IN CONCRETE The damage to the concrete due to corrosion of reinforcement is considered to be one of the most serious problems. It is an universal problem and property worth of crores of rupees is lost every year. Due to corrosion problem in bridges, buildings and other RCC structures, India incurs heavy loss of about Rs. 1,500 crores annually. This paper deals with various causes of corrosion and remedial measures thereon. Corrosion process and mechanism : Corrosion of reinforcement steel is a complex phenomenon involving chemical, electrochemical and physical processes. When reinforcement steel rusts, the volume of iron oxide formed is 2-4 times greater than the steel corroded, which results in bursting stresses in the concrete surrounding the bar. This causes cracking, spalling and delamination of concrete. Another consequence of corrosion is reduction in cross- Sectional area of the steel at anode, thus reducing its load ca
Post a Comment
Read more
REBOUND HAMMER TEST The SCHMIDT rebound hammer, developed by a Swiss Engineer Ernst Schmidt in 1948 is one of the most frequently used methods worldwide for non-destructive testing (NDT) of concrete structural elements. The test is based on the principle that the rebound of an elastic mass depends on the hardness of the surface against which the mass impinges. The hammer consists of a plunger connected with a spring-driven metal mass. The plunger is held against at 90 to the smooth concrete surface, firmly supported and pressed. This will impart a fixed amount of energy. Upon release, the metal mass rebounds, the plunger being still in contact with concrete. The distance travelled by the metal mass or the amount Larger is the rebound. higher is the strength of concrete. of rebound is noted on a scale that gives an indication of the concrete strength. The rebound hammer test is sensitive to local variations in the concrete: for instance, the presence o
Post a Comment
Read more