Construction And Quality Control Key Techniques Of Lime-flyash Base

With more attention paid to transportation industry, and the rapid development of national economy, the high-grade highways have developed at fast speed. Presently, the high-grade highways in China mostly adopt semi-rigid base and asphalt pavement as structural form. The commonly-used semi-rigid bases in our road engineering are:cement-stabilized granular class, lime stability of aggregates, comprehensive stable aggregates, etc. With merits like high intensity, good endurance, and low cost, these bases are widely-used in road engineering. Lime-fly-ash bases possess high long-term strength and excellent board body performance, and thus they have better crack resistance and resistance of freezing than the crushed stone cement base. Meanwhile, they have rich sources of materials—industrial waste fly ash has been transformed to favorable paving materials, and thus reduce the amount of the occupation of land and environmental pollution, and they are convenient for construction, lime-fly-ash bases are increasingly popular in the construction of the high-grade highways. Yet, after the long usage of these bases, the inherent disadvantages present problems like the cracking of structure, which causes the cracking and clamorous pulp in the lime-fly-ash based bituminous pavement, and thus the deformation and damage of the road surface, and then consequently its service life. Though at present semi-rigid base-featured construction technology is more and more mature and greatly-improved, yet its problems pop up in actual construction, such as the amount of ash in the mixing process of lime-fly-ash and the control of mix proportion, the segregation during the paving process, the control of water content during the rolling process, etc. Only with these problems solved, could its demerits be overcome to the minimum and thus truly ensure the quality of construction.