Effect Of Coarse Aggregate On Compression Behavior Of Normal Strength Concrete Confined With Basalt Fiber Reinforced Polymer Sheet By Using Different Mix Design Methods

Nowadays,different coarse aggregate sizes and types with fibre-reinforced polymers(FRP)are widely used to improve the mechanical properties,primarily compressive strength and fracture behaviors,durability,ductility and crack control capacity of concrete.Coarse aggregate in concrete mix can be an implicit factor that plays an essential role in concrete strength.Basalt fibre is a new kind of high-performance inorganic fibre,which is characterized by high temperature and abrasion resistance,high tensile strength,and high failure strain.The purpose of this research is to investigate the effects of coarse aggregate on the compressive strength and fracture energy of normal strength concrete designed by different mix design methods and concrete externally confined with basalt fibre reinforced polymer(BFRP)sheet.Different types of concrete specimens,i.e.,the cube of size 150 mm×150 mm× 150 mm,cylinders of sizes 150 mm × 300 mm and 100 mm×200 mm respectively,were cast.Basalt fibre sheets were used for external confinement of cylindrical specimens.Concrete specimens were tested at the age of 28 days of curing according to the relevant ASTM standards.The compression tests were carried out under displacement control mode.From the test results,it was found that coarse aggregate size has a notable influence on the compressive behaviors of normal strength plain concrete.The type and shape of coarse aggregate affects the compressive behaviors of normal strength concrete significantly.The plain concrete with high crushing strength coarse aggregate gives considerably higher compressive strength,accumulated energy and fracture energy than the concrete made with low strength coarse aggregate.The concrete mix design has an influence on the compressive behavior of normal strength plain concrete due to variation in concrete ingredients.The BFRP external confinement has a profound influence on the compressive behaviors of normal strength concrete.The compressive strength,accumulated energy and fracture energy of normal strength concrete increased significantly after the BFRP external confinement.The BFRP external confinement is more effective with larger coarse aggregate size than the smaller coarse aggregate size.