Study On Mechanical Properties And Application In Road Surface Of Construction Waste Recycled Concrete

This issue is from the Graduate Innovation Fund of Jiangxi Province project“Study on Application in Road Surface of Construction Waste Recycled Concrete”,grant No.: YC2015-S063.In this paper, firstly, the amount of construction waste in Jiangxi Province was investigated, the statistical result showed that it is increasd year by year. Then the research status of performance of recycled concrete, pavement performance and the status of it used in road surface been briefly introduced. And tested on the physical properties of construction waste recycled coarse aggregate and mechanical properties of construction waste recycled concrete. The results showed that, compared with natural coarse aggregate, recycled coarse aggregate had following characteristics,apparent density is smaller, water absorption and crushing value is bigger. The compressive strength and flexural strength of construction waste recycled concrete were reduced with the increase of water cement ratio. When 25% of recycled coarse aggregate is waste brick coarse aggregate, the basic mechanical properties of construction waste recycled concrete is meet the material requirements of the new cement road surface. While the amount of admixture is 50%, waste brick coarse aggregate had a greater influence on the mechanical properties of recycled concrete.Through rational mixture ratio design and modification, construction waste recycled concrete could be used in the higher level of road surface.At the end of this paper, we put forward some proposals on construction waste recycled concrete used in road surface. In order to enhance the performance of recycled concrete, mineral admixture such as fly ash and could be mixd in recycled concrete, or the concrete slab reinforced with steel bar. The water of construction waste recycled concrete had two parts, supplementary water and the water of rmixture proportion, the amount of supplementary water could be calculated as 75% water absorption of the waste brick coarse aggregate. The content of waste brick coarse aggregate in recycled coarse aggregate should be controlled within 25%.