REGENERABLE ASPHALT-CONCRETE MIX AND METHOD OF PREPARING THEREOF Russian patent published in 2001 - IPC

FIELD: repair of road coatings of highways and city roads, sidewalks and grounds. SUBSTANCE: regenerable mix comprises, wt.%: crushed asphalt-concrete, 30-70; broken stone and sand, 28-66; mineral powder, 6-14, bitumen, 2-7. In this case, amount of crushed asphalt concrete in each particular mix is established according to formula wherein AN is old crushed asphalt-concrete, wt. % is heat capacity of broken stone and sand, Cal/kg.deg; C_bs+p is heat capacity of bitumen, Cal/kg.deg; C_B is heat capacity of mineral powder, Cal/kg.deg; C_MP is heat capacity of asphalt-concrete, Cal/kg.deg; C_AB is weight of broken stone and sand in single batch, kg; m_bs is weight of bitumen in single batch, kg, m_B is weight of mineral powder in single batch, kg; m_MP is broken stone and sand heating temperature, C; is t_h is final mix temperature, C; t_m is bitumen heating temperature C; t_MP is mineral powder temperature, C; M is weight of mix of single batch, kg: r_B is specific heat and water evaporation heat; W is moisture content of crushed asphalt-concrete. Crushed asphalt-concrete and mineral powder are sued at ambient temperature, mineral materials (broken stone and sand) are heated to 210-330 C, and organic binder is heated to working temperature. Batched mix components are combined and stirred (1st stage) to homogeneous volumetric distribution of cold and hot materials, then kept under thermostated conditions to heat cold components and weaken bitumen bonds in crushed asphalt-concrete grains, and mix is finally stirred (2nd stage) till homogeneous state is formed. EFFECT: samples of regenerated asphalt-concrete mix have ultimate compression strength at 20 C of 4.1-5.0 MPa; at 50 C of 1.1-1.2 MPa water-saturated samples, is 4.5-5.8 MPa; water saturation is 2.6-3.0 vol. %; swelling is 0.9-0.19 vol. %. 4 cl, 1 ex, 1 tbl