Experimental Study On Mechanical And Fatigue Properties Of Glass Fiber Reinforced Concrete

Because of the rich raw materials,high compressive strength and good durability of cement concrete,it is widely used in road and housing construction projects.But the flexural and crack resistance of ordinary cement concrete is poor,and often can not reach the design life.Therefore,many scholars began to consider adding fiber materials to concrete to improve all aspects of performance of concrete.As glass fiber has strong corrosion resistance,bending resistance,tensile properties and other high quality properties,so glass fiber can effectively improve the performance of concrete.The reference concrete strength of the test design is C30.On this basis,ordinary glass fiber and alkali resistant glass fiber with the dosage of 3kg/m~3,6kg/m~3,9kg/m~3and 12kg/m~3are added respectively.54 standard cube specimens are made,27 of which are used for cube compression test and 27 for splitting tensile test.108 standard beam specimens were made,27 of which were used for bending test and 81 for bending fatigue test.Through the cube compression,splitting tensile,bending and bending fatigue tests of different types of concrete specimens,the influence of glass fiber type and content on the mechanical properties and bending fatigue properties of GFRC is explored.The Weibull distribution theory is used to analyze the fatigue life of GFRC.The main research work is as follows:(1)Through the compressive and splitting tensile tests of cube specimens,the compressive and splitting tensile strengths are obtained.The influence of glass fiber type and content on the compressive,splitting tensile properties of GFRC is explored,the failure modes of the specimens are recorded and analyzed.(2)Through the flexural test of the beam specimen,the flexural strength is obtained,the influence of the type and content of glass fiber on the flexural performance of GFRC is explored,and the failure mode of the specimen is recorded and analyzed.At the same time,the ultimate load of the specimen is recorded to prepare for the bending fatigue test.The tension compression ratio and flexural compression ratio of the specimens are calculated,and the influence of the type and content of glass fiber on the brittleness of GFRC is explored.(3)The fatigue life of GFRC under different stress levels is obtained by bending fatigue test of beam specimens under three stress levels,and the strain fatigue curve is drawn.(4)Through the Weibull distribution analysis of the fatigue life of GFRC,whether it is two parameter Weibull distribution is tested,and its double logarithmic fatigue equation is deduced.The fatigue life of GFRC under different failure probability is calculated.At the same time,the fatigue limit strength of GFRC is calculated...