Influence factors of bond performance between asphalt surface layer and semi-rigid base

Referring to foreign LPDS shear test method,the influence of asphalt mixture,sticky layer material,semi-rigid base material,the interface of asphalt mixture and sticky layer material,the interface of viscous layer material and semi-rigid base on the shear strength between asphalt surface layer and semi-rigid base was studied with self-designed interior direct shear test and oblique shear test.The shear strength and the unit shear strength were the test evaluation indexes.It is shown that increasing the maximum nominal size and the compactness of asphalt mixture can improve interlayer bond strength.High strength,coarse and dense semi-rigid material can improve interlayer bond strength.Viscosity isn't main influence factor to select viscous layer materials,but the species and doses of viscous layer materials should be selected according to engineering practice test.Cleaning the surface of semi-rigid base is an important measure to improve bond interlayer's level.Prime coat should be sprinkled with 0.3~0.6 L·m-2 after the surface of semi-rigid base is cleaned.Casting single particle size,coarse specification and alkaline crushed stone above interlayer hot asphalt is easy to construct,and can improve interlayer bond strength.15 tabs,6 figs,10 refs.