6 tensile strength of cement

Concrete Technology, Construction material, Cement

1. University of Salahaddin/ College of Engineering 2015-2016
Dept. Of Dams & Water resources Engineering By: Goran Adil

Test No. 6
Test Name: Tensile strength of cement.

Introduction:
Cement is very weak in tensile strength. Its strength is determined directly using the briquettes.

Purpose:
To find the tensile strength of the cement.

Materials:
1- Ordinary Portland cement.
2- Standard sand ( Rounded single size particles passed on sieve 850 µm (No.20) and not
more than 10% pass through sieve 600 µm (No.30) ).
3- Water.

Apparatus:
1- Cement tensile strength machine.
2- Briquettes, the thickness of the briquettes is 25.4 mm and the minimum area of its cross
section is 645 mm
2
.
3- Balance.
4- Container.
5- Hand gloves, Trowel, and Scoop.
6- Glass Graduates.

Procedure:
1- Prepare cement-sand mortar, with a mix proportion 1:3 and water to both weights of
cement and sand ratio of 8 %. Use 50 grams of cement.
2- Mixing cement and sand at dry condition for one minute then add the water and continue
the mixing for 4 minutes.
3- Oiling the internal faces of the mould.
4- Place the mould on the sheet of glass and fill it with a mortar.
5- Strike surface of the paste in a mould by a spatula until full compaction has achieved.
6- Level the surface of the mortar.
7- Store the moulds in air under temperature about 20±1
o
C and a minimum relative humidity
of 90 %, for 24±0.5 hour.
8- Open the moulds and take out specimen.
9- Testing the specimens which has the shape No. 8, using direct tension testing machine.
10- Apply the load until the failure of specimen and record the failure load.




Calculation:

Tensile strength of cement A
p
 MPa.
Where: P = failure load (N).
A = sectional area of the specimen (mm
2
)

2. University of Salahaddin/ College of Engineering 2015-2016
Dept. Of Dams & Water resources Engineering By: Goran Adil

Specification:

Iraqi standard specification 5/1984
Age 1 day
Tensile strength of rapid hardened cement (MPa) 2.1


Discussion:
- Compare the test results with the standard specifications.
- What is the significance of this test?

3. University of Salahaddin/ College of Engineering 2015-2016
Dept. Of Dams & Water resources Engineering By: Goran Adil

Data Sheet
Tensile strength of cement



Test No.: 6
Test name: Tensile strength of cement


Name of the student:
Group No.:
Date:




Group
No.
Age
day
Failure load
N
Tensile strength
MPa












Results: