Precast concrete is reinforced concrete that is cast away from the building site, and assembled on site. On its own it concrete has good compressive strength, but lacks tension and shear strength and can be subject to cracking when bearing loads for long periods. While GFRP Rebar offers high tension and shear strength to make for what concrete lacks. Traditionally used reinforced bars behave similarly to concrete in changing environment, which means they will shrink and expand with concrete resulting in cracking.