Controlled Crack Growth Tests for Optimization of Micro-Fiber Reinforced Cement Composites
N. Banthia and I. Genois
Appears on pages(s):
carbon fiber; fiber reinforced concrete; fracture
mechanics; fracture toughness; R-curve; steel fiber
Crack propagation in cement-based matrices reinforced with micro-fibers of steel and carbon was studied using contoured double cantilever beam specimens. Influence of fibers, sand and silica fume was quantified using crack growth resistance curves. It was demonstrated that these fibers enhance the resistance to both nucleation and growth of cracks, and that such fundamental fracture tests are very useful in developing micro-fiber composites with a high performance. The influence of number of variables which would otherwise have remained obscured in normal tests for engineering properties become apparent in the fracture tests. The paper points out the desired durability characteristics of these composites and discusses their current and future applications.