As a result of increasing railway traffic, speed and axle loads, existing railway tracks, especially those which were built on soft ground, often show signs of distress and settlements. These have a serious influence on the safety and economy of existing railway lines. As an economic measure for the rehabilitation and/or upgrading of existing railway lines, geogrids or geocomposite products for reinforcement, filtration and separation have successfully been installed in many projects and decisive product properties for these materials have been specified by Railway Authorities.
The geogrid reinforcement restrains lateral deformations of the sub-base through shear interaction, which reduces permanent horizontal strains and vertical stresses in the long run. The geotextile component, as separation and filtration layer, prevents mixing of the fine subgrade (clay/silt) with the coarse base course, which prevents distortion of the whole track superstructure.
The improvement in load distribution achieved by the geogrid together with the separation function of the geotextile allows reduction of sub-ballast layer thickness, which in turn reduces the carbon footprint, as less fill material is required to achieve equivalent performance to conventional, non-geosynthetic solutions. Examples of potential reduction in CO2 emissions will be given on the basis of project examples.
The presentation will also cover latest results of large- scale tests, full scale field trials as well as long term monitoring on geogrid reinforced ballast/ sub ballast layers in Australia and across the world.
About the presenter
Jorg Klompmaker is a German qualified engineer specialising in soil reinforced structures, pavement engineering and waste management design issues. Jorg has previously worked with the German geosynthetic manufacturer ‐ Luckenhaus, where he was involved in the development of geosynthetic use in soil and asphalt reinforcement applications. For the last thirteen years, Jorg has been employed by the German consultancy BBG as the Senior Technical Consultant engaged in Road and Railway Engineering, Reinforced Earth Structures (including embankments on soft soils), Landfill and Hydraulic Engineering. Jorg has a deep understanding of a wide range of geosynthetics that are commonly used in such applications. Jorg has either written, or co‐authored some 70 technical publications that have been presented at various technical conferences throughout the world. Jorg is a member of a number of Technical Committees that include; Technical Committee 210‐Dams and Embankments – International Society for Soil Mechanics and Geotechnical Engineering ISSMGE; Working Committee Ak 6.4 Landfill Technology‐ German Association for Geotechnics.