The impact of natural fibers' characteristics on mechanical properties of the cement composites.

The paper reviews the properties of cement composites reinforced with short fibres. The effect of natural fibres was investigated: cotton, sisal, jute, ramie, bamboo, and synthetic fibres: polymer and polypropylene. It was noticed that the fibres change the consistency of the mixture up to 15%. In the composite flexural strength tests, a change in strength by +/- 8% was observed, depending on the type of fibres used. The research shows that the use of natural fibres had a positive effect on the compressive strength by 27%, while the use of synthetic fibres caused its decrease by 4%. Additionally, it was noticed that the chemical composition, the diameter and the total length of the fibres in the element have an impact on the composite shrinkage. The fibre-containing composites showed an 8% higher water absorption compared to the non-fibre samples. The exception is the ramie fibres, which reduce water absorption. In general, a positive effect of natural fibers on the properties of cement composites has been noticed, however, in case of natural fibres application, a thorough further properties investigation is recommended.