Polypropylene Fiber Thin Layer Of Cement Concrete Pavement Rapid Repair Materials Performance Research

In recent years, the breakage of our country concrete road is increasingly serious, leading to sharp grow in concrete pavement repairing. An important factor were the poor abrasion resistance and weak impact resistance. In view of this, this paper taking the polypropylene fiber to prepare the thin rapid repairing material of Cement concrete pavement to improve the performance of repairing concrete. The main contents and conclusions of the study are as follows:1.Studies the compatibility of gelatinization materialof thin rapid repair material in depth. The results indicates: the time of setting and workability can satisfy construction require of job location, the flexural strength and the compression strength were 4.1MPa,16.9MPa respectively, can satisfy with the requirement of opening to traffic at 2 hours, flexural strength of 1d was 7.4MPa, have completely reached the designing strength, when P.O, SAC and UFA go together with suitable comparison and cement-sand ratio is 1 '. 1. And later period strength will increase steadily, flexural strength and the compression strength of 28 day ages were 16.2 MPa,64.7MPa respectively. The incorporation of 3% SF, the compression strength of 28 day ages was 75.4MPa.2. Based on the optimized mixture proportion, this paper systematically studies the factors affecting the mechanical properties of rate of sand, different gelatinization compatibility, and the amount of polypropylene fiber. The results indicates: after casting, the flexural strength and the compression strength of 4 houe ages were 4.7MPa,18.4MPa respectively of the thin rapid repairing Concrete of Cement Concrete Pavement, when with due W/B, rate of sand, gelatinization compatibility and the amount of polypropylene fiber, which satisfied the requirement of opening to traffic at 4hours. Flexural strength of 1day ages reached 100% of designing strength. Later period strength increased steadily, flexural strength and the compression strength of 28 day ages were 16.4 MPa, 85.0MPa respectively. The incorporation of 5% SF, the compression strength of 90 day ages was 85.8 MPa. 3. The bond strength of new-old concrete enhances with the increasing of age. The incorporation both of polypropylene fiber(0.9kg/m~3) and SF(5%), the bond strength of new-old concrete of 28 day ages was the biggest, reached 4.0MPa, which increased 25% than the undoped.4. This paper studed on the abrasion resistance of the thin rapid repairing Concrete prepared by polypropylene fiber, mainly discussed the factors affecting the abrasion resistance of fast hardness and high early strength Concrete of Cement Concrete Pavemen of rate of sand, different gelatinization compatibility, and the amount of polypropylene fiber. The results indicates: after casting, with the appropriate mix proportion, the thin rapid repairing concrete can improve the abrasion resistance of the concrete at early stage, reduce the wear rate of unit surface area. 1 day ages of wear rate was only 3.224kg/m~2 , less than professional standard (JC/T421-2004) required 3.600kg/m~2.5. Polypropylene fiber can enhance impact resistance of Concrete greatly. The most suitable amout of polypropylene fiber is 0.9kg/m~3, impact toughness of 4 hour ages and 1day ages incressed by 1.6time, 1.7time than the undoped respectively, so as absorbing energy when cracking, incressed by 83%, 100%, than the undoped respectively.6. Establishing mathematical model for the thin rapid repairing Concrete to predict the abrasion resistance of concrete, except individual measurement of wear rate has big relative error to predictive value, the other relative errors were small, so the prediction modelof the abrasion resistance of Concrete has the good prediction accuracy, can be able be used for research on Predictionof the abrasion resistance of the thin rapid repairing Concrete.