Technology Research Of Full-Depth And High Performance Cement Stabilized Gravel Base

Asphalt pavement with cement stabilized gravel base is wildly used in the construction of high-grade highway in our country. With the increase of traffic volume, the thickness of the grassroots will reach more than 30cm. Restricted by paving machinery, layered paving is needed in the actual project. However, layered paving technology violates the design concept that the basement applies the whole stress in the pavement structure design. The whole stress is changed into two thin layers of stress, and a serious stress concentration phenomenon appears between the two layers. Thus the use of pavement performance and service life is reduced.With the appearance of ultra wide paver and large tonnage vibrating road roller, the construction technology in full-depth of cement stabilized gravel base is possible. In this paper, big thickness vibration compaction meter which can mold the actual construction thickness at the basement is used to design the mix proportion of the full-depth cement stabilized gravel base, and the comparative research on mechanical properties, durable performance and shrinkage cracking performance of three different basements in interlayer contact is studied. The comprehensive evaluation method TOPSIS is used to evaluate the three kinds of basement. The results show that the road performance of the full-depth basement with continuous contact between the layers is better than the basement with poor contact between the layers.The finite element software ABAQUS is used to analyze the mechanical response of two kinds of construction technology--layered construction and full-depth construction. The results show that the simulation results of full-depth construction are 80% in deflection value of the layered construction,33.5% in the maximum principal stress at bottom of surface layer of the layered construction,52.5% in the maximum principal stress at bottom of basement layer of the layered construction,69% in the minimum principal strain at top of the soil base of the layered construction, and 77% in the maximum shear stress at bottom of surface layer of the layered construction. Furthermore, the mechanical index of full-depth construction technology in a 29cm basement is better than layered construction technology in a 35cm basement.Based on an actual project--test road in Mashan-Pingguo highway in Guangxi province, the construction technology with a full-depth cement stabilized gravel base is studied, the research results provide technical support to Guangxi province even the whole country on the construction technology with a full-depth cement stabilized gravel base, and has a certain guiding significance to the subsequent promotion of this full-depth cement stabilized gravel base.