High And Low Temperature Performance Of Fly Ash Polyester Fiber Asphalt Mixture

Asphalt mixture pavements have a large demand for stone and mineral powder,and the processing of mineral powder also consumes a lot of energy.Fly ash can be used in asphalt mixture instead of mineral powder,but the addition of fly ash will lead to a decrease in low temperature crack resistance of asphalt mixture.In order to ensure the overall performance of fly ash asphalt mixture,polyester fiber is added to fly ash asphalt mixture to study the high and low temperature performance of asphalt mixture.In this paper,the high-low temperature performance of asphalt mixture with different fly ash content(0,20%,40%,60%,80%,100%)and different polyester fiber content(0,0.3%,0.35%,0.4%,0.45%,0.5%)is studied by Marshall stability test and splitting test.Find the optimum combination of fly ash and polyester fiber without reducing the performance of the original asphalt mixture.The main conclusions drawn are as follows:(1)The effect of fly ash on Marshall stability of asphalt mixture is first increased and then decreased.When the content of fly ash is 80%,the Marshall stability of the test piece reaches the maximum,which is 12.16%higher than the original asphalt mixture.The effect of fly ash on the flow value of asphalt mixture was first decreased and then increased.When the content of fly ash is 40%,the flow value drop to the lowest,which is 3.47%lower than the original asphalt mixture.The effect of fly ash on the Marshall modulus of the asphalt mixture is first increased and then decreased.When the fly ash content is 40%,the Marshall modulus of the test piece reached the maximum,which is 10.88%higher than the original asphalt mixture.(2)The effect of polyester fiber on Marshall stability of asphalt mixture is first increased and then decreased.When the content of polyester fiber is 0.4%,the Marshall stability of the test piece reaches the maximum,which is 14.39%higher than the original asphalt mixture.The influence of the polyester fiber on the flow value of the asphalt mixture is first decreased and then increased When the polyester fiber content is 0.3%,the flow value of the test piece reached the minimum,which is 0.39%lower than the original asphalt mixture.The effect of polyester fiber on the Marshall modulus of the asphalt mixture is first increased and then decreased.When the polyester fiber content is 0.4%,the Marshall modulus of the test piece reached the maximum,which is 10.88%higher than the original asphalt mixture.(3)The addition of fly ash and polyester fiber can improve the Marshall stability of the asphalt mixture.When the fly ash content is 40%and the polyester fiber content is 0.4%,the Marshall stability of the asphalt mixture reaches the maximum.At this time,the Marshall stability is 20.58%higher than the Marshall stability of the original asphalt mixture,while the flow value is decreased by 4.63%and the Marshall modulus is increased by 22.94%.(4)The effect of fly ash on the splitting tensile strength of asphalt mixture is gradually reduced.When the content of fly ash is 100%,the splitting tensile strength of the test piece decreases by 17.23%.The effect of fly ash on the tensile strain of the asphalt mixture is gradually increasing.When the fly ash content was 100%,the tensile strain at break of the test piece increased by 7.27%.(5)The effect of polyester fiber content on the splitting tensile strength of asphalt mixture is gradually increased.When the polyester fiber content is 0.5%,the splitting tensile strength increases by 6.37%.The effect of polyester fiber on the tensile strain of the asphalt mixture is gradually increased.When the content of the polyester fiber is 0.5%,the tensile strain at break of the test piece is increased by 11.82%.(6)The addition of fly ash reduces the splitting tensile strength of the asphalt mixture,but the addition of polyester fiber can compensate for the loss of a part of the splitting tensile strength.When the content of polyester fiber is 0.4%and the content fly ash is 40%,the splitting tensile strength of the asphalt mixture is almost equal to the splitting tensile strength of the original asphalt mixture,and the tensile strain at break at this time is increased by 10.00%.Figure 35 Table 22 References 53.