Mai Lan NGUYEN's blog

Anyone know the Garwood method which is used to determine the fracture energy of concrete (composite materials)?

Garwood method: with a load - load line displacement curve of an three point bending fracture test (or SENB), we have firstly:

J0=2U0/B(H-a0)

After, an iterative relation is used:

Jn=Jn-1(H-an)/(H-an-1)+2Un/B(H-an-1)

B,H : width and height of the beam respectively.

a : crack length 

In fact, it's not clear the determination of the initial value Jo. 

Hi everyone,

Anyone can tell me how to determine the fracture energy for crack propagation in a 4 points bending notched beam (mode I)?