STRUCTURAL DESIGN MODEL AND ECONOMIC FEASIBILITY OF USING CONCRETE FILLED GLASS FIBER REINFORCED EPOXY TUBE COLUMNS

Structural design of Concrete Filled Tube CFT columns requires defining an appropriate thickness and material of confining tube. The Glass Fiber Reinforced Epoxy GFRE is a sustain material that provides resistance against salt and sulphates. Experimental program of circular CFT columns was carried out to verify the applicability of the ACI provisions using available local materials, which consists of six specimens divided into two groups: reinforced and un-reinforced CFT columns, studied parameters were: compressive strength of CFT columns, axial strain, hoop strain, load – strain behavior, and failure behavior. It was found that satisfying the ACI requirements achieves a conservative evaluation of CFT ultimate compressive strength and axial strain of concrete with average factor of safety of 2.15 in predicting compressive strength. An applicable design model proposed depending on ACI 318 [3] and ACI 440.02 [4] specification, providing reasonable prediction of confined concrete strength 𝑓 𝑐𝑐′ and the size effect of CFT columns. Also, an economic study of using CFT columns based on volume of its peer reinforced concrete was made to assure its economic feasibility comparing to the traditional reinforced concrete columns.