Method for renovating a roadway and machine for simultaneous spreading of fibres and bitumen emulsion

A spreading machine for simultaneously spreading fibers and bitumen emulsion for a vehicle traffic pavement renovation method, the machine comprising:

• a reserve of fibers;
• a bitumen emulsion tank containing a trackless bitumen emulsion;
• and
• a bitumen emulsion and fiber spreading system including
• a first bitumen emulsion spreading boom,
• a fiber spraying device, and
• a second bitumen emulsion spreading boom,
• the first and second bitumen emulsion spreading booms including nozzles,
• the first bitumen emulsion spreading boom, the fiber spraying device, and the second bitumen emulsion spreading boom being disposed to spread successively and superimposed, during travel in a single passage of the spreading machine on the vehicle traffic pavement to renovate,
• a lower bituminous tack coat comprising bitumen emulsion sprayed by the first bitumen emulsion spreading boom, then
• an intermediate coat of fibers comprising fibers sprayed by the fiber spraying device, said sprayed fibers having a maximum length of 12 cm (4.7 inches), then
• an upper bituminous surface coat comprising bitumen emulsion sprayed by the second bitumen emulsion spreading boom, to bind the sprayed fibers between two coats of trackless bitumen emulsion, the trackless bitumen emulsion containing hard bitumen, the trackless bitumen emulsion providing a residual binder once a breaking of the emulsion is obtained, the residual binder of the trackless bitumen emulsion having the following properties:
• a penetration grade lower than 40 dmm (0.157 inches) and a Ball-Ring temperature higher than 50° C. (122° F.), and the trackless bitumen emulsion includes from 30% to 70% of bitumen, from 30% to 70% of water, from 0.1% to 10% of at least one surfactant and at least one additive, the percentage being in weight.