Mix proportion design method for constant-temperature modified asphalt mixture

Abstract

The invention provides a mix proportion design method for a constant-temperature modified asphalt mixture. The method comprises the following two steps: determining the mineral aggregate gradation and the optimal asphalt-aggregate ratio of the mixture, wherein the method is characterized in that the mineral aggregate gradation adopts multi-gravel gap gradation constructed by a power function; and forming a test piece by adopting a rotation compacting method and determining the optimal asphalt-aggregate ratio according to the asphalt-aggregate ratio corresponding to the tightest state and the maximum dry density of minerals under the condition of different asphalt-aggregate ratios. By adopting the method provided by the invention, the mix proportion design method for the constant-temperature modified asphalt mixture can be normalized, so that the quality of the constant-temperature modified asphalt mixture can be guaranteed.

Description

technical field [0001] The invention belongs to the technical field of highway engineering, and in particular relates to a mixing ratio design method of normal temperature modified asphalt mixture. Background technique [0002] In recent years, with the development of transportation technology, "energy-saving, low-carbon, and environmentally friendly" road construction materials have emerged, especially the emergence of solvent-based cold-mixed and cold-paved modified asphalt, which has made up for the road performance of previous water-based cold-patch materials. Poor, unsuitable for full-width paving and technical defects, this type of material has received more and more attention and research because of its significant technical advantages. Compared with traditional hot-mix asphalt mixture and warm-mix asphalt mixture, its It consumes less energy and releases less harmful gases, and can be constructed under low temperature and negative temperature conditions, which solves...

AI Technical Summary

Problems solved by technology

However, for room temperature modified asphalt mixture, the asphalt binder has been in a lubricated state for 7 days at room temperature, and the cementation strength of the hot mix asphalt binder after cooling has not been formed. , it is not easy to form a parabolic curve between the asphalt ratio and dry density, and it is difficult to find the asphalt ratio corresponding to the maximum dry density (the most compact state of mineral material)

In addition, in the actual use process, if the existing mixing ratio design method of hot mix asphalt mixture is copied, there will be problems such as the inability to determine the optimum asphalt ratio, the low mechanical performance indicators of normal temperature asphalt mixture, and the failure to meet the design requirements. , which will seriously restrict the large-scale application of normal temperature modified asphalt mixture

[0005] Although the United States, Japan and other countries have carried out systematic research, a complete set of technical system has not yet been formed. There has not been targeted and in-depth research on the mix ratio design of normal temperature asphalt mixture, and no systematic mixture ratio design method has been proposed.

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