Method for fine design of Buton rock asphalt mixture

Abstract

The invention relates to a method for fine design of a Buton rock asphalt mixture. The method comprises the following steps of: (1) testing the asphalt content, the ash content, and the concrete gradation of ash of Buton rock asphalt; (2) obtaining an asphalt mixture which does not contain the Buton rock asphalt according to the Marshall design method; (3) determining the blending proportion of anasphalt component in the rock asphalt according to a modified asphalt test of the rock asphalt; (4) determining the proportion of ash in concrete gradation in the Buton rock asphalt mixture through calculation according to test results obtained in the step (1), the step (2) and the step (3); (5) adjusting the proportions of fine aggregate and mineral powder in the concrete gradation according tothe calculation result obtained in the step (4); and (6) according to the result obtained in the step (5), according to the situation that asphalt-aggregate ratio of a common asphalt mixture is changed at the interval being + / - 0.3%, determining the optimum asphalt-aggregate ratio of the Buton rock asphalt mixture by the Marshall design method. The method disclosed by the invention has the characteristics of being easy to realize, simple and fine, and excellent in mixture performance, and can better exert the effect of the Buton rock asphalt in asphalt mixtures.

Description

technical field [0001] The invention belongs to the technical field of road engineering, and in particular relates to a method for finely designing Buton rock asphalt mixture. Background technique [0002] Buton rock bitumen is called an active agent in Indonesia, and its bitumen content is about 20% to 30%, and the rest is limestone minerals. The indoor research and engineering application results show that: Buton rock asphalt can not only effectively improve the high temperature performance, water damage resistance and fatigue performance of asphalt mixture, prolong the service life of the pavement, but also has simple construction technology, strong operability, and good performance. promotion and application prospects. [0003] At present, in the design process of Buton rock asphalt mixture, most studies still regard Buton rock asphalt as a modified additive. The design methods of Buton rock asphalt mixture mainly include the following: Add different dosages of Buton r...

AI Technical Summary

Problems solved by technology

The difference between the refined design of Buton rock asphalt mixture proposed by this application and the above-mentioned patent is that: ① the above-mentioned patent uses the optimum asphalt dosage of the first-stage base asphalt in the second stage, and the optimal asphalt dosage +0.2 %, +0.4%, -0.2%, -0.4% (the amount of asphalt is the sum of asphalt in base asphalt and rock asphalt) when designing the target mix ratio, the base asphalt and Buton rock asphalt in the total amount of asphalt are not considered. The proportion of natural asphalt components is specified or explained in detail, and the influence of natural asphalt components on base asphalt is not considered, so the method for determining the optimal rock asphalt content cannot be given; ② The meaning of the content of asphalt is different. The asphalt dosage of Buton rock asphalt mixture is defined as the sum of asphalt in base asphalt and rock asphalt, while the asphalt dosage in the patent of the present invention refers to the amount of base asphalt and does not include the natural asphalt in Buton rock asphalt; ③The above-mentioned patent basically does not mention the ash content in Buton rock asphalt, but the patent of the present invention incorporates the ash distribution into the gradation design to replace part of the fine aggregate and mineral powder

Obviously, the defect of the above-mentioned patents is that neither the method for determining the optimal rock asphalt content nor the influence of ash distribution is considered, so the Buton rock asphalt mixture cannot be accurately designed.

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