Ground improvement and rebuild of a district roadin complex geotechnical-engineering conditions – case study

Abstract

Local roads in Poland, built for the most part in the previous economic system, are mostly unsuited to the ever-increasing traffic load, often built on a low-load organic substrate and need to be renovated. Linear objects are most often characterized by a significant variability in groundwater conditions in their area. The economical and safe design of the rebuild of a road structure often entails the need to implement ground improvement design of the low-bearing soil substrate, but areas of improvement should be adapted to the occurrence zones of low-bearing soil. The article presents a case study of the district road, for which ground and water conditions were recognized and organic soil were found. In addition to the rebuilding of the road structure to fulfill the requirements of the current traffic load and repairing the culverts, the reconstruction also included the ground improvement. The authors reviewed the types of road categories according to the admissible traffic loads (KR), the most important and commonly used methods of ground improvement, discussed the characteristics of the Benkelmann beam deflection method, proposed a design solution adapted to the existing conditions in the substrate and, after implementing it, presented the results of the deflection of the road before and after the reconstruction and soil improvement.

Keywords

• low-bearing soil
• complex ground-water conditions
• soil improvement
• deflection method