Abstract:

Reinforced retaining wall has been widely used in highway construction, however, the vertical settlement, cross cracks of the pavement and outward-dipping deformation and other defects have occurred. These defects can even lead to partial collapse that impacts the traffic. Based on the defect survey of the reinforced retaining wall in Harbin City, the main forms of the defects are summarized. A section of road with typical defects is selected as an example to investigate the influences of fill properties, fill voids, ribbon fracture, seepage, traffic load and other factors on the horizontal deflection and the axial force using finite element software MIDAS-GTS NX. The causes of the defects of the reinforces retaining wall are systematically analyzed. Results show that the defects of the retaining wall are caused by the integrated actions of soil pressure, traffic load, pavement seepage and many other factors. The values of C and φ of the fill are the sensitive factors of the horizontal displacement of retaining wall. The pavement crack and seepage lead to the moisture increase, resulting in the decreases in C and φ, which is the factor of the outward-dipping deformation. Ribbon fracture, fill void and traffic load are important factors that lead to horizontal deformation of the retaining wall. This study may provide reference for the maintenance and strengthening of reinforced retaining walls.

Key words: road engineering, reinforced retaining wall, diseases, soil property, causes analysis