Regarding the quality issues of grouting material rolling construction, through some previous construction experience and discussions, today, I will give you a comprehensive analysis and discussion. First, analyze and position the quality of the raw materials, and then focus on the quality of the asphalt mixture. The countermeasures to avoid mixing quality control problems are listed, and then the paving quality control of asphalt mixture will be analyzed.
1. Quality control analysis of raw materials
1. Aggregate quality control
Aggregate is divided into two categories: coarse aggregate and fine aggregate. Coarse aggregate The material is required to be hard, free of weathered particles, clean and close to a cubic shape, and the content of flaky particles must be strictly controlled; the fine aggregate is required to be hard, dry, non-weathered, free of impurities and have an appropriately graded artificial rolling mechanism. Sand, unqualified aggregates are not allowed to be loaded into trucks, and the quality of the aggregates is strictly ensured. In addition, many stones can meet various technical specifications of the specifications under normal temperature conditions, but they may not be able to meet them at high temperatures. This requires high-temperature crushing value analysis of the aggregates. The instruments involved in the high-temperature crushing value test have pressure Crushing value meter, balance, press, metal rod, metal copper, square hole cylinder and square hole screen.
2. Asphalt quality control
Since asphalt has the characteristics of high-temperature deformation and vulnerability to water erosion, in terms of quality control of asphalt mixtures, the high-temperature stability of asphalt mixtures should be investigated properties and water stability. For high-grade highways, the solubility index is more important. The specific index values can refer to the pavement structure layers and previous engineering experience. For the SBS modified asphalt used in the middle and upper layers, the solubility It is required to be equal to or greater than 99%, the segregation softening point difference is equal to or less than 2.5 degrees Celsius, the flash point is greater than or equal to 230 degrees Celsius, the elastic recovery at 25 degrees Celsius is equal to or greater than 75%, and the penetration index PI is not less than 0.
3. Filler quality control
The moisture content is equal to or less than 1%, the particle size range is 100% less than 0.6 mm, 90% to 100% less than 0.15 mm, 75% to 100% less than 0.075 mm, and there is no agglomeration or clumping in appearance. The water coefficient is less than 1. </p
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