Pavement Structure for Low-capacity Roads with Different Recycled Materials Utilization

In road construction various recycling techniques are well-known and long-term developed worldwide. Commonly recyclable materials, known as reclaimed asphalt pavement, are used. These materials are gained during the pavement rehabilitation process. In some cases further secondary granular materials are used, e.g. masonry or concrete recyclable material (MRM or CRM) coming from demolition works. Utilization of recyclable materials in pavement structure is specified in Czech Republic by technical requirements, focusing above all on recycled asphalt pavement (RAP), lesser then on other granular materials especially for the sub-base layers. The trend is to use recyclable materials in one structural layer of the pavement.

Authors are introducing experimental design of an alternative pavement structure, where the recyclable materials are used in protection layer, sub-base and/or binder course all at once, eventually in wearing course as well. The main techniques are: MRM reinforced by synthetic fibres and cold recycling technique with RAP, bituminous emulsion (or foam bitumen) and cement as combined binder. Pavement rehabilitation techniques based on cold processes are from the environmental and economic point of view without any doubt of benefit. The paper summarizes the present laboratory experience with these techniques and comments results of experimental tests of odd structural materials and the pavement structure with both materials. Strength properties as well as stiffness and cohesion of two layers made by different technique is introduced and discussed.