Construction of “Panemunė Bypass” Highway in the Nemunas River Delta. Problems of 2003–2015 Roadbed Exploration, Design, and Construction
In the Republic of Lithuania, there had been almost no experience in the road (roadbed) construction prior to the Panemunė bypass in terms of very complex geological, geotechnical and paleogeomorphological territories. All the roads constructed in previous decades in the Nemunas River Delta were built practically without special geotechnical and geological research and the resulting problems were solved either on the spot during construction or rectified later upon the emergence of reclaimed deformation. The article analyzes the whole process of the geological and geotechnical research during the bypass construction – from the first exploration work and designing to construction completion. The geological and geotechnical research stages are described; methods, research conditions, mistakes made, and recommendations for geotechnical investigations under similar conditions in the future are given. At the same time, the article contains the detailed geological and geotechnical conditions of the bypass, roadbed construction problems, forecasts of the roadbed seating during the design and construction with the assumption of additional factors. The article provides and analyses the actual results of the bed deposition monitoring and further forecast of the bed deposition.