Wstęp

English version

Projekt „Przyjazne dla środowiska mieszanki mineralno-asfaltowe na ciepło jako nowoczesne rozwiązanie technologiczne zwiększające wydajność budowy nawierzchni asfaltowych” jest realizowany przez Mostostal Warszawa oraz jednostki naukowe Politechnikę Warszawską Wydział Inżynierii Lądowej oraz Instytut Badawczy Dróg i Mostów Zakład Technologii Nawierzchni.

Environmental friendly warm mix asphalt as innovative technological solution, which increases the capacity of road paving.

In connection with growing traffic volume and necessity of new roads construction, it is important to enable bituminous mix paving while air temperature is below 5 Celsius degrees. Low temperature speeds up the drop in bituminous mix temperature during transport and rolling. This may result in insufficient density of the pavement layers which can cause damages in an early stage of exploitation – road construction may have inadequate strength for carrying the traffic load.

Overall objective of the MMA^c project is to develop solution which can limit the problem of low air temperature. It is possible due to the warm mix asphalt technology which consist in asphalt mix modification that reduces the temperature of pavement rolling to 80 Celsius degrees (which is 20-30 degrees less than using traditional hot mix technology). In spite of low temperature warm mix asphalt surface can be compacted as well as hot mix. Moreover it is possible to reduce the manufacturing temperature to 120 Celsius degrees, which contributes to limitation of environmental harmful gases emission.

Project is divided into two phases. In the first part laboratory tests of asphalt binder and bituminous mixes are planned. These materials will be modified by three kinds of additives, which reduce technological temperatures in different ways. Waxes modifies the viscosity and elasticity properties of asphalt binder, chemical additives have surface-active influence on material and zeolites cause “micro-foaming” effect. Main objective of the laboratory tests is to choose the most effective additives and  determine an optimum amount of additive in relation to binder/mix. Afterwards, tests of the asphalt mixes will be carried out to select most universal additives which do not have an influence on the strength of the compacted mix.

In the second part of the project, test run of the warm mix asphalt production in a mix plant will be executed. Also construction of sample road section is planned. Asphalt mix plant might need a redesigning, which is also taken into consideration during project works.

Mostostal Warszawa is coordinator of the MMA^c Project in which also Road and Bridge Research Institute and Warsaw University of Technology (Bituminous Composite Group) take part.