Mechanical Properties and Performance under Laboratory and Field Conditions of a Lightweight Fluorogypsum-Based Blend for Economic Artificial-Reef Construction

This paper investigates the mechanical properties under laboratory and field conditions of a concretelike blend made of fluorogypsum (FG), fly ash, and portland cement for artificial-reef construction, which is referred to as a FG-based blend. The 28-day compressive strength and relative volumetric expansion of the FG-based blend were statistically characterized. After 1 year of immersion in brackish water under field conditions, the compressive strength of the FG-based blend experienced a moderate reduction when compared with material under laboratory conditions but did not degrade below its 28-day value. Visual examination of the immersed specimens indicated that aquatic organisms are attracted to the proposed material. Field investigation of a small artificial-reef structure made of a FG-based blend indicated that sea floor settlement due to the weight of the structure was small. A preliminary cost analysis comparing the cost of artificial reefs constructed with different materials suggests that the proposed FG-based blend is a promising environment-friendly economic material for artificial-reef construction