A STUDY by scientists in Germany and the United States could help engineers understand how materials fail and buildings collapse.
Boffins at the Max Planck Institute for Metals Research in Stuttgart, Germany and the Massachusetts Institute of Technology in the United States have simulated how cracks spread through materials microscopically.
By studying the speed of spread of cracks through brittle materials the engineers showed that fracture stability is controlled by material at the tip of the crack.
Materials are subjected to extreme forces at this point and most tend to stiffen and turn brittle under the strain.
In some cases a crack in a brittle material can travel faster than the speed of earthquakes. The faster a crack travels through a brittle material the more it changes from a regular failure to one with unstable and irregular surfaces. This can be seen in materials including ceramics and polymers.
By studying the relationship between stress, strain and cracking in solids they found that cracks become nonlinear due to the deformation of the material near a crack tip.
Markus Buehler at the Massachusetts Institute of Technology said: 'Our simulations show that the key to understanding the experimental observations is to consider the material behaviour close to the breaking of bonds.' He claimed this would help improve the understanding of how buildings crack and fail under loading.