Tension Test

Tension testing is a common method used to evaluate the mechanical properties of materials. When applied to bamboo, it can provide valuable information about the strength and stiffness of the material, which can be useful for designing and constructing bamboo structures. These measurements can then be used to calculate important mechanical properties, such as the ultimate tensile strength, the yield strength, and the Young's modulus of elasticity. 

Aim:

This test is performed to find the maximum tensile stresses, tensile modulus of elasticity and stress-strain curve in the bamboo test specimen.

Dimensions:

As no dimensions for the tab are defined in the code, they were considered according to the gripping condition in the lab. Experimentally, it was found out that this dimension can be – width = 20 mm and length = 60 mm. 

Key:

δ    wall thickness

b    width of specimen [b<(δ/2)<20mm]

1    culm section

2    gauge length = 50mm to 100mm

3    tabs

Loading Rate:

The tests were done on Bambusa Tulda and Psudoxytenanthera (Madhavi). It was found that both these species of bamboos are structurally very similar. The time for these tests is to be 300 +/- 120 seconds. Having found the strength of Bambusa Tulda to be ~ 66 MPa from ISO 22175 (2019), and checking the c/s of the gauge of specimens, a speed on 0.002 mm/s was set for the test.


σ_ult=66 MPa

c/s=12×6=72 mm²

force=66×72=4.75 kN

E=10000 MPa 

From that,ε=0.0066 mm/mm

For a 100 mm long gauge length, elongation would be=0.66 mm

For 300 seconds, test speed=0.002 mm/sec


These calculations can be used to find the test speed for different species of bamboo.

Number of Tests :

Code specifies to try at least 3 samples with node at the centre, we plan to do atleast 5.

Expression of results: