Scrims are oriented continuous fiber fabrics. The continuous fiber is usually yarn or roving. The continuous strands are not inter-woven but are laid over each other at ninety degree orientation and then a binder is applied which holds the fabric structure in place.
Various types of scrim are possible depending on the spacing between the strands and the number of parallel strands as shown in figure (1) below.
Types of scrim for GFRC that are commercially available:
Scrims are particularly used in conjunction with chopped strand reinforced mixes. When they are placed in the tensile regions of the product they care significantly increase the flexural strength of the composite.
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