Classifications

• • E—FIXED CONSTRUCTIONS
  • E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
  • E01C—CONSTRUCTION OF, OR SURFACES FOR, ROADS, SPORTS GROUNDS, OR THE LIKE; MACHINES OR AUXILIARY TOOLS FOR CONSTRUCTION OR REPAIR
  • E01C23/00—Auxiliary devices or arrangements for constructing, repairing, reconditioning, or taking-up road or like surfaces
  • E01C23/06—Devices or arrangements for working the finished surface; Devices for repairing or reconditioning the surface of damaged paving; Recycling in place or on the road
  • E01C23/065—Recycling in place or on the road, i.e. hot or cold reprocessing of paving in situ or on the traffic surface, with or without adding virgin material or lifting of salvaged material; Repairs or resurfacing involving at least partial reprocessing of the existing paving
• • E—FIXED CONSTRUCTIONS
  • E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
  • E01C—CONSTRUCTION OF, OR SURFACES FOR, ROADS, SPORTS GROUNDS, OR THE LIKE; MACHINES OR AUXILIARY TOOLS FOR CONSTRUCTION OR REPAIR
  • E01C11/00—Details of pavings
  • E01C11/16—Reinforcements
  • E01C11/165—Reinforcements particularly for bituminous or rubber- or plastic-bound pavings
• • E—FIXED CONSTRUCTIONS
  • E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
  • E01C—CONSTRUCTION OF, OR SURFACES FOR, ROADS, SPORTS GROUNDS, OR THE LIKE; MACHINES OR AUXILIARY TOOLS FOR CONSTRUCTION OR REPAIR
  • E01C7/00—Coherent pavings made in situ
  • E01C7/08—Coherent pavings made in situ made of road-metal and binders
  • E01C7/18—Coherent pavings made in situ made of road-metal and binders of road-metal and bituminous binders
  • E01C7/187—Repairing bituminous covers, e.g. regeneration of the covering material in situ, application of a new bituminous topping

Definitions

• the present invention relates to a process for the cold regeneration of an aged pavement covering constituted by aggregates coated in a binder by the use of a pavement regeneration machine known per se consisting in particular of a vehicle self-propelled comprising, in the direction of advancement, milling members, kneading members of milled products with the addition of a regeneration binder as well as distribution members on the pavement of the asphalt thus treated.
• a pavement regeneration machine known per se consisting in particular of a vehicle self-propelled comprising, in the direction of advancement, milling members, kneading members of milled products with the addition of a regeneration binder as well as distribution members on the pavement of the asphalt thus treated.
• the roadways are covered with aggregates coated in a bituminous binder at least four centimeters thick.
• the first and simplest is to add a layer of asphalt to the one that has aged or has suffered degradation.
• This solution is not likely to give any satisfaction given that the new layer does not always adhere well to the old and risks to come off and that there is also a risk of leading to roadways of too great thickness, which is not without problems.
• this solution is not capable of solving the problem of detachment of the underlying layer and is therefore not satisfactory from the angle of mechanical reinforcement.
• Another solution consists in milling the existing asphalt which one puts at the landfill and replacing it with a new one: this process has the advantage of making it possible to obtain a roadway being at the initial level;
• this solution is also not likely to give complete satisfaction, on the one hand, from the economic point of view, given its expensive nature, and, on the other hand, with regard to environmental protection. since it causes significant waste which can only accumulate on landfills.
• the object of the present invention is to remedy these drawbacks by proposing a method making it possible to control at any time the progress of the various operations which follow one another during the implementation of a regeneration workshop as mentioned above, and this, as well mechanical point of view only from the chemical point of view, by acting mainly on the characteristics of the milling of the mixes, and on those of the regeneration binder added during the mixing, so as to be able to redeposit on the pavement a product whose properties are predetermined, and correspond essentially to those of the product initially deposited, before aging.
• bituminous binders most often studied to determine the properties of these binders is the penetrability at 25 ° C (AFNOR standard NFT 66 004): to measure this, a cup containing the bituminous binder in a water bath at 25 ° C, a needle is placed on its surface carrying a weight of 100 grams and its penetration is measured for 5 seconds.
• AFNOR standard NFT 66 004 to measure this, a cup containing the bituminous binder in a water bath at 25 ° C, a needle is placed on its surface carrying a weight of 100 grams and its penetration is measured for 5 seconds.
• experience shows that, starting from a penetration value of between 60 and 70, the penetration of an aged binder of about 10 years old drops to around 5 to 20 tenths of a mm.
• the object of the invention is to develop, on the basis of these theoretical considerations, a process for the cold regeneration of an aged pavement covering making it possible to redeposit on the pavement a regenerated covering whose characteristics are the closest possible from those of the coating initially deposited.
• the process according to the invention is characterized in that, in a first phase, the characteristics of the aged asphalt are determined in the laboratory, in particular the nature of the aggregates as well as the content and the characteristics of the binder, then, from the values thus determined, the characteristics and the content of the regeneration binder to be added during the use of the regeneration machine are calculated at the level of the mixing members.
• the regeneration operation is carried out using the regeneration machine by milling the coating aged over a predetermined thickness using milling members known in themselves constituted by at least one milling rotor disposed in a decohesion chamber provided with decohesion bars and constituted by a drive tube disposed substantially transversely to the direction of advance of the machine and on which are wound turns each carrying a series of teeth in particular nt provided with tungsten carbide tips, so as to obtain a crumbling of the milling, then, by bringing the milling thus treated to the level of the kneading members where the regeneration binder is added whose characteristics have been determined during the first phase of the process then the coating thus regenerated is brought to the distribution members which deposit it on the roadway.
• milling members known in themselves constituted by at least one milling rotor disposed in a decohesion chamber provided with decohesion bars and constituted by a drive tube disposed substantially transversely to the direction of advance of the machine and on which are wound turns each carrying a series of teeth in
• This process therefore makes it possible to fully control the characteristics of the coating deposited at the end of treatment to make them correspond to a large extent to those of the initial coating thanks to the use, in combination, of mechanical means (particular characteristics of the milling members and mixing) to obtain a crumbling of milled products unrelated to the coarse grinding obtained with traditional milling bodies) and chemical means allowing a rational choice of the quantity and characteristics of the regeneration binder added during mixing.
• the regeneration binder is constituted by a bitumen or a mixture of bitumens with high penetrability and heavy oils with naphtheno-aromatic character and and distinguished from conventional bitumens of similar consistency by contents in weak asphaltenes and strong aromatic compounds.
• regeneration binders which can be advantageously used within the framework of the process according to the invention
• products marketed by the company SHELL under the trade name, RJO 100, RJO 200, RJO 400, RJO 800, RJO 1002.
• Other products which can also be used for a similar purpose including the products marketed by ESSO under the trade names FLEXON 110 and FLEXON 150.
• about 10% of a wetting agent is added to the regeneration binder capable of accelerating the process of decohesion of the milled product by softening the aged binder.
• This wetting agent which consists of an essentially aromatic solvent and whose flash point in a closed cup (standard NFT 60 103) is greater than 50 (aromatic content between 50 and 100%), is not an integral part regeneration binder, but has a chemical action on the straw which it promotes crumbling.
• wetting agent As an example of a wetting agent, mention may be made of the product sold by the company ESSO under the name HAN 8070.
• the total amount of regeneration binder to be added to the milling material at the level of the kneading members is calculated by the formula (I) and the penetrability of this binder by formula (II) formulas in which: Xn represents the binder content chosen in the mix after recycling (parts per hundred parts of aggregates). Xv the binder content of the aged mix (parts per hundred parts of aggregates) y the percentage of regeneration binder in the asphalt binder after recycling Pr the penetration of the regeneration binder Pn the penetrability chosen for the asphalt binder after recycling. Pv the penetrability of the aged binder.
• this layer may simply consist of a layer of the regenerating fraction distributed in a homogeneous manner and at a flow rate proportional to the surface to be treated.
• 0.10 to 0.50%, preferably between 0.25% by weight, is added to the milling piece, at the level of the kneading members, and downstream of the regenerating fraction.
• synthetic fibers in particular polyacrilonitrile fibers considered relative to the weight of the milled material. These fibers improve the tensile strength of the regenerated mix.
• the teeth of the milling rotor or rotors are continuously cooled by spraying an aqueous solution containing 5 to 40%, preferably about 10% of a surfactant.
• a surfactant which is especially chosen from the group consisting of amines, polyamines and amine hydrochlorides.
• This surfactant is to improve the contact between milling and regeneration binder by "doping" the interface between these two compounds.
• the regenerating quantity (excluding wetting agent) and its penetrability were calculated from formulas I and II above.
• Example 2 We started with the same aged starting millet as in Example 1, and an aqueous solution composed as follows was sprayed on: 80% water 20% of Dinoram 50 (aqueous dispersion of CECA amines) at a rate of 1% by weight relative to the initial straw.
• Dinoram 50 aqueous dispersion of CECA amines
• Example 2 The procedure was exactly as in Example 2 except that it was incorporated after the regeneration binder and at the level of the mixer 0.25% by weight (relative to the milling) of polyacrilonitrile 100 detex fibers 24 mm Hoechst VFII. A regenerated binder was thus obtained having the following DURIEZ LCPC characteristics at 18 ° C: Compactness 95% Rc 8 d in MPa 18 ° C 4.15

Landscapes

• Engineering & Computer Science (AREA)
• Architecture (AREA)
• Civil Engineering (AREA)
• Structural Engineering (AREA)
• Mining & Mineral Resources (AREA)
• Road Repair (AREA)
• Road Paving Structures (AREA)
• Compositions Of Macromolecular Compounds (AREA)
• Road Signs Or Road Markings (AREA)
• Footwear And Its Accessory, Manufacturing Method And Apparatuses (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (2)

Family

ID=9349943

Family Applications (1)

Country Status (8)

Cited By (2)

Families Citing this family (4)

Citations (4)

Family Cites Families (10)

• 1987
  • 1987-04-09 FR FR8705005A patent/FR2613737B1/fr not_active Expired - Fee Related
• 1988
  • 1988-04-05 DE DE8888400817T patent/DE3863383D1/de not_active Expired - Fee Related
  • 1988-04-05 US US07/177,781 patent/US4846602A/en not_active Expired - Fee Related
  • 1988-04-05 EP EP88400817A patent/EP0286531B1/de not_active Expired - Lifetime
  • 1988-04-05 AT AT88400817T patent/ATE64768T1/de not_active IP Right Cessation
  • 1988-04-05 ES ES88400817T patent/ES2022997B3/es not_active Expired - Lifetime
  • 1988-04-08 CN CN88101961A patent/CN1016723B/zh not_active Expired
  • 1988-04-08 CA CA000563719A patent/CA1281575C/fr not_active Expired - Fee Related

Patent Citations (4)

Non-Patent Citations (4)

Also Published As

Similar Documents

Legal Events