Experimental Study On Axial Tensile Performance Of Low Volume Fraction Of Ternary Hybrid Fiber Reinforced Concrete

One effective way to improve the strength and toughness of cement-based concreteis mixed with fibers.If high ductility fiber and high modulus fiber are added into theconcrete at the same time, making the two kinds of fiber playing a role of enhancing andtoughening in different structural levels and different loading stage, the concrete ofexcellent comprehensive mechanical properties should be obtain, so hybrid fiberconcrete is formed.The direct tensile properties of fiber reinforced concrete reflected animportant aspect of its good performance.It has yet to reach a unified about uniaxialtension specimen forms and methods of axial tensile test of fiber reinforced concrete inacademic circles at home and abroad, Main reason related to axial tensile specimen ofheterogeneity, severe stress concentration, the experiment system stiffness anddeformation in the process of measurement difficulties.The different way of the specimen holder and the shape,the effects on the measuredresults of the test are different. Currently, the holding widely used methods can bedivided into a buried, clamp and paste style. The disadvantage for the existence of avariety of clamping methods, the paper conducted the following studies by designing anew type stretch joints of fiber concrete direct tensile test, improving the method offiber reinforced concrete under uniaxial tensile test, hybrid fiber reinforced highperformance concrete is configurated by selecting steel fiber and polypropylenemonofilament fiber and crude fiber imitated steel wire:(1)Experimental research oftension and compression ratio of hybrid fiber concrete;(2)The analysis of equivalenttensile strength of hybrid fiber reinforced concrete;(3) Axial tensile properties of hybridfiber reinforced concrete is discussed with the fiber composition, length to diameterratio of steel fiber, the types of steel fiber, active additive.The results indicate that: witha combination of slenderness ratio of80and47.1kg/m3arched steel fiber,2.6kg/m3macro-polypropylene fiber and1.0kg/m3dura fiber, the tensile properties of HFRC arethe best.