12/13/2011
Hot crushed stone mastic mixes (CSMA) are applied in construction of the highway of international importance “Western Europe – Western China” while arrangement of upper courses of pavements, providing non-defective passage of heavy traffic.
New requirements are made to the surfacing of the highways and overall to pavements in conditions of modern traffic with the increased loading and speed. To the opinion for the majority of specialists of transport-developed countries, these requirements predetermine the necessity for construction of roads with hot crushed stone mastic mix, which allows providing of non-defective passage of heavy traffic.
Such technology has been used for the first time in our country for construction of circular road around Almaty city, then for the highway Astana-Shchuchinsk. At present it is used in the construction of the highway of international importance “Western Europe – Western China”.
References: Hot crushed stone mastic mixes (CSMA) are referred to the independent class of asphalt concrete mixes. As opposed to macro-rough high-crushed stone mixes of open type, mixes CSMA have the increased content of bitumen. To keep such amount of bitumen on the surface of crushed stone, it is necessary to include into the mix special stabilizers, for example, cellulose fibers.
Mixes CSMA are prepared by mixing in asphalt mixing plant in the heated condition crushed stone, sand from screenings of crushing, asphalt filler and bitumen, taken in rationally matched ratio, with compulsory inclusion of stabilizers of fibers or polymers types. The stated mixes are recommended to use for arrangement of wearing courses for pavement. Pavements from CSMA are characterized by the improved exploitation properties. Laboratory tests and immediate supervisions for the condition of protective courses of pavement in Scandinavian countries and Canada have proved the high durability of crushed stone mastic asphalt concrete to the abrasive action of studded tires.
One more important property is that the level of noise while movement of motorcars along pavement from CSMA is considerably lower compared with the similar parameter for ordinary asphalt concrete pavement.
