Table 2.

Physical and mechanical properties of fibres.

Fibre Type	Length (mm)	Diameter $\left(\mathsf{\mu }\mathrm{m}\right)$	Aspect Ratio	Tensile Strength (MPa)	Elastic Modulus (GPa)	Density (g/cm3)
Steel (S)	10	120	83	2500	200	7.8
AR glass (ARG)	13	18	720	1500	74	2.8
Polyvinyl alcohol (PVA)	8	38	210	1600	40	1.3
Polypropylene (PP)	6	32	188	450	3.5	0.91