Improving the design of the subgrade in the construction of culverts

Abstract

The article considers the issues of assessing and improving the quality and reliability of culverts and the road drainage system on roads with unpaved and transitional types of pavement. The authors performed a number of field studies aimed at assessing the operational condition of culverts and pavement above them on roads of territorial significance in the Khabarovsk Territory. The issues of the influence of the quality of culverts on the condition of the road surface are examined in detail. Systematized and analyzed data on the influence of the presence (absence) of defects in the body of culverts on the quality of the road surface. The data are ranked by the diameter of the pipe hole and the size of the protective layer, and the degree of influence of the quality of the culvert on the quality of the road surface depending on the thickness of the protective layer is determined. The relationship between defects in culverts and the quality of the road surface is established. Based on the result of mathematical modeling, a nomogram of the dependence of the state of the coating over the culvert on the thickness of the backfill over the pipe and the condition of the culvert is constructed. In a specialized software package, by the finite element method, an assessment of the stress-strain state and structural stability of the subgrade with a culvert under the influence of the normative static load on the structure is carried out. The results of mathematical modeling showed that there is a significant decrease in the stability of the structure, especially with low embankments. To increase the stability and reduce the deformation of the structure, the authors proposed a method of strengthening the embankment of the subgrade in places of the device, which on the basis of mathematical modeling showed its high efficiency.