Flexible Plug Joint System with New Material

Up to now the common material used for flexible plug joints of bridges has been based on bituminous mixtures consisting of aggregates and elastomeric-modified binders. All existing national regulations and also the European Guideline for Expansion Joints ETAG 032 are restricting flexible plug joints to these traditional bituminous mixtures. All existing asphaltic mixtures are susceptible for plastic deformations at higher temperatures including rutting whereas they cause significant reaction forces at low temperatures. These properties limit the application of the traditional joints to areas with moderate climate. In practice asphaltic plug expansion joints also often fail in the intersection between adjacent pavement and joint, causing cracks and leakages. The new expansion joint system shows essential improvements in the intersection pavement/joint by mechanical means and uses a new material based on polyurethane, which does not show negative temperature affine properties and can be processed in cold condition. The new flexible plug joint system also enables new applications, both for a wider climatic range and more complicated geometries. Furthermore the new flexible plug joint allows for larger movements up to more than 100mm and addresses a longer design working life. As the new design is not covered by existing standards and verification methods in the first phase a comprehensive research had to executed after consultation with leading European experts from Germany, Switzerland and Austria. The paper covers reports on material and system tests executed during national and European approval procedures at several European testing institutes and shows examples of installation.