Research On Semi-rigid Base Performance Of High-grade Highway

Since asphalt concrete overlays , extensively used in high-gradation roads construction, are weak in rigidity, it has more restrictions on intensity and stability of both basement and root basement.According to some concrete features of semi-rigid basement asphalt overlays and domestic pavement construction practices, the paper presents varieties of economic and reasonable semi-rigid basement materials consistent with the requirement of high-grading overlays, which are of different specification and raw material composing, and some key technical essentials about construction techniques and blueprints, as well as quality-controlling management, by detailed investigations and researches, mass information collecting, and systemic interior examinations and project testing. It also takes some successful experiences of semi-rigid asphalt overlays used in highway basement both at home and abroad for reference.The paper presents that appropriate gradation enables basement to obtain compactness principle(. It fulfills interspaces with finer and binding materials that enables semi-rigid basement with adequate intensity. It also presents that improvement on the contractibility of materials could reduce overlays cracking, and stabilized cement granule could retard the influence of time on intensity.Lime-stabilized soil, as main basement material, was extensively utilized in pavement construction of different grading. Varieties of treatments should be taken according to soil varieties, and meantime, the amount of binders should be dominated precisely for a satisfying effect.The paper also presents that certain amount of sweller does a visible effect on reducing dry-shrink cracking of stabilized concrete granular through primary research on stabilized granular basement of micro-expansion concrete by interior experiment and overlays testing.