Flexural Test on Concrete Beam Mould, procedure and application


To evaluate the tensile strength of concrete, a flexural test is performed on concrete beam. This test checks the ability of unreinforced concrete beam to withstand failure in bending.
The flexural test on concrete can be conducted using 3-point load test.

What are the Applications of Flexural Test on Concrete?
Flexure test is an essential requirement for concrete mix design, it is employed in testing concrete for slab and pavement construction. In some countries, it is an essential requirement for concrete mix design.

Procedure of Flexural Test on Concrete
  1. Take out the specimen from curing tank and place on the loading points of flexure testing machine.
  2. Center the loading system in relation to the applied force and bring the block applying force in contact with the specimen surface at the loading points.
  3. Start applying loads between 2 to 5 percent of the computed ultimate load.
  4. Apply load on to the specimen continuously without shock till the point of failure at a constant rate (Indian standard specified loading rate of 400 Kg/min for 150mm specimen and 180kg/min for 100mm specimen, stress increase rate 0.06+/-0.04N/mm2.s).
The loading rate can be computed based on the following equation:

r = Sbd2 / L

Where:
r = loading rate
S = rate of increase of extreme fiber
b = average specimen width
d = average specimen depth
L = span length 

Measure the cross section of the tested specimen at both ends and at the center to calculate average depth & height. 

Computation of Modulus of Rupture 
The following expression is used for estimation of modulus of rupture:
MR = 3PL / 2bd2 

Where: 
MR: modulus of rupture

P: ultimate applied load indicated by testing machine
L: span length
b: average width of the specimen at the fracture
d: average depth of the specimen at the fracture

Watch Moulding and Demoulding demonstration of Plastic and Polyurethane concrete moulds on You Tube Channel of Zeal International.


Zeal International is manufacturing Polyurethane beam moulds in India under make in India initiative. Polyurethane beam moulds are durable and lightweight. The are also easy to clean and maintain. These  moulds are rust proof and have longer work life in comparison to traditional moulds. Please visit http://www.zealinternational.com/materialtesting/concrete/moulding-equipment/plastic-beam-mould for more information on Polyurethane Beam Moulds.

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