This draft European Standard describes two test methods:
- basket method (see Clause 4),
- beaker method (see Clause 5).
The basket method describes a method for determining binder drainage of bituminous mixtures. This method directly measures binder drainage, but when carried out on bituminous mixtures with fibres or mixtures whose mortar content is higher than in porous asphalt some clogging of the holes in the drainage baskets can occur, limiting the drainage of the binder. The basket method can be used either for determining the binder drainage for different binder content, or with a single binder content, eliminating the successive repetitions. It also enables the effects of varying fine aggregate types or including any anti-draining additive to be quantified.
The beaker method describes a method for determining binder drainage of bituminous mixtures. It is applicable to asphalt materials that are not porous asphalt or for porous asphalt incorporating fibres. It can be used either for determining the binder drainage for different binder content, or with a single binder content, eliminating the successive repetitions. It also enables the effects of varying fine aggregate types or including any anti-draining additive to be quantified.