Research On Influence Of Differential Settlement Of Widening Subgrade On Semi-rigid Asphalt Pavement

Arming at the key technique of widening highway, depending on the widening project of Lalin-Wuchang-ShengJie highway, combining with on-site survey data, the additional stress field and displacement field of the foundation under the new and old subgrade were analyzed through ABAQUS finite element analysis software. After discussing effect factors of geometry parameters of widening embankment, properties of fillers and construction scheme etc, the development rule of deformation of widening embankment was analyzed. Referring to the practical situation of the project to investigate the deformation rule of the embankment under different schemes, put forward the corresponding proposal and give the recommended program.Finite element analysis model was established to study the mechanical effect of differential settlement on pavement structure, calculation and analysis of the development rule of additional stress in each layer of pavement structure with different amount of differential settlement. Consolidated the two requirements of pavement functional and structural, proposed the control standards of differential settlement after construction. The typical cross section was selected for analysis and calculation, got the settlement-time curve of each control point on widening embankment surface. According to the obtained control standard of differential settlement after construction to determine the reasonable time of paving semi-rigid asphalt pavement structure. The mechanical model of semi-rigid asphalt pavement was established, combined with the factor of strength and stiffness to make sensibility analysis for the internal forces and pavement deflection property of structural layer, and provide the basis for crack resistance of pavement and rational combination. Analyzed the development rule of the maximum tensile stress under different crack width, and compared with the pavement structural stress after laying geogrid to put forward engineering measures to prevent cracking destruction of semi-rigid base.