Study On The Application Of Cement-stabilized Cold In-place Recycling Base

The recycling of old asphalt pavement mixture is favor to improving resource utilization efficient and environment. This technology is in accordance with our national guideline on sustainable development, e.g., circle economy. Study on the recycling of old asphalt pavement materials is of importance in the filed of highway engineering.The technology of old asphalt pavement materials cold in-place recycling is beneficial to both road engineering and environment, mainly due to the features of rapid construction, less interfering with traffic, improving road bearing capacity with minor line alignment grade alteration. As a result, the application of this technology can reduce construction resource requirement, cost, and waste material disposing.In this thesis, experimental comparisons show that the key factors of controlling the size-distribution of the recycled old asphalt pavement materials include the nature and the size-distribution of the old asphalt pavement materials, milling depth, the moving speed of road milling machine, and the rotate speed the machine rotor. These are key factors to recycling mixture design.The reaction mechanism of the cold recycling mixtures with cement additive and micro-texture analysis show the texture of the mixtures are rational and can meet the technical requirement of the second class and the third class roads. Laboratory tests on the ratio of cement additive and mixture, the period of mixture curing show that the strength of the cold recycling mixtures heavily depends on the ratio of cement additive and the size-distribution of the old asphalt pavement materials. The early strength of the cement-stabilized recycling mixture is relatively large and the strength of the mixtures, e.g., unconfined compressive strength, increases with the increase of cement content and curing period. The size-distribution of the mixture has a key influence on its strength.Based on the study on the construction procedure of the cement stabilized cold recycling mixtures base, inspection method and quality control index are proposed for the construction of cement-stabilized in-place cold recycling mixture base. The result from a test section shows that cement-stabilized in-place cold recycling mixture base is applicable to the construction of the second class and the third class roads.