The mix types AC EME 22 C1 and C2 are characterised by the following composition parameters: Grain size distribution, binder content , modulus de richesse and void content. In order to improve the cold properties of the mix, there is only a margin in the binder, the fines and any additives.
In a first step, the properties of the mortar will therefore be optimised by means of DSR tests. Various modification options will be evaluated, such as polymer-modified binders, additives, highly modified binders, natural asphalts, chemical additives. Since today EME mixes are only produced with RAP, the mortar from the RAP is also included in the optimisation. In order to make this possible, a procedure is being developed for extracting the mortar from the RAP, whereby in this context mortar is understood as binder + filler + fine sand (< 1 mm). To characterise the mortar properties, tests are carried out at the DSR in a wide temperature range. While several test methods with asphalt mastic (bitumen + filler) are described in the literature, only few data are available for asphalt mortar (bitumen + filler + sand). It will therefore be necessary to specify the testing technique on the DSR with mortar up to 1 mm in size.
After optimising the mortar component, EME 22 mixtures will be produced and evaluated using the classic E-modulus and fatigue tests.