HIGH-PERFORMANCE COATED MATERIAL FOR PAVEMENT AND A ROAD SURFACE

• US 20130022737A1
• Filed: 03/22/2011
• Published: 01/24/2013
• Est. Priority Date: 04/06/2010
• Status: Active Grant

• Current Assignee: Eiffage Travaux Publics (Eiffage SA)
• Original Assignee: Eiffage Travaux Publics (Eiffage SA)
• Inventors: Olard, Francois, Krafft, Serge
• Granted Patent: US 8,915,995 B2
• Time in Patent Office: Days
• US Class Current: 427/138
• CPC Class Codes: E01C 7/182 Aggregate or filler materials, except those according to E01C7/26 E01C7/187, E01C7/353 take precedence; different aggregates or fillers E01C7/18

Abstract

The invention relates to coated material for the base layer of road pavement, made up of aggregate coated with a hydrocarbon binder, wherein the aggregate is more than 95 wt % of the coated material; wherein the aggregate includes a granular structure, which includes a plurality of granular fractions d/D; one intermediate fraction of which is less than 15% of the granules; wherein the hydrocarbon binder is less than 5 wt % of the coated material; wherein the coated material includes, after compacting, a void fraction of less than 8%; wherein the hydrocarbon binder is a hydrocarbon binder modified by adding polymers or oil, or modified by foaming or by emulsion, by means of which the modulus of rigidity of the coated material, once compacted, is higher than 9000 MPa.

Claims

1. A coated material for a base layer or binder layer of a road or highway pavement, or for industrial, port, or airport platforms, or for a supporting layer for railroad tracks,

wherein said coated material is composed of aggregate mixed with at least one hydrocarbon binder,

wherein the aggregate represents more than 95% by weight of the coated material, and the hydrocarbon binder represents at most 5%,

wherein the aggregate comprises a granular structure comprising several particle size fractions d/D, each particle size fraction being defined by a lower limit and an upper limit,

wherein the aggregate comprises a first particle size fraction d1/D1 having as median a first median dm1, and a second particle size fraction d2/D2 having as median a second median dm2,

wherein the aggregate comprises a third particle size fraction d3/D3 between the first and second particle size fractions, having as lower limit d3 the upper limit D1 of the first particle size fraction, and having as upper limit D3 the lower limit d2 of the second particle size fraction,

wherein the third particle size fraction has a ratio of its weight relative to the weight of the aggregate,

wherein the width of the third particle size fraction D3−

d3, defining a relative width (D3−

d3)/D2 in relation to the upper limit of the second particle size fraction, said relative width being greater than 20% of D2,

wherein the ratio of the weight ratio of the third particle size fraction and its relative width is less than 0.4, which is;

2. The coated material according to claim 1, wherein the ratio between the first median dm1 and the second median dm2 is less than 0.33, and preferably less than 0.25.

3. The coated material according to claim 1, wherein the width of the third particle size fraction D3−

d3 is greater than 30% of D2−

d1, and preferably greater than 40%.

4. The coated material according to claim 1, wherein the ratio between the weight ratio of the third particle size fraction and its relative width is less than 0.25, which is:

5. The coated material according to claim 1, wherein the ratio between the weight ratio of the third particle size fraction and its relative width is greater than 0.10, which is:

6. The coated material according to claim 1, wherein the hydrocarbon binder has a needle penetration depth, measured at 25°

C. as defined in standard EN 1426, that is greater than 30 tenths of a mm.

7. The coated material according to claim 1, wherein the fatigue resistance of the coated material, once compacted, measured at a temperature of 10°

C. and at a frequency of 25 Hz according to standard NF EN12697-24, is greater than 110 microstrain and is preferably greater than 130 microstrain.

8. The coated material according to claim 1, wherein the modulus of rigidity of the coated material, once compacted, measured at a temperature of 15°

C. and at a frequency of 10 Hz according to standard NF EN12697-26, is greater than 11000 MPa and is preferably greater than 14000 MPa.

9. The coated material according to claim 1, wherein the hydrocarbon binder is without fibers.

10. The coated material according to claim 1, additionally comprising a fourth particle size fraction d4/D4 and a fifth particle size fraction d5/D5 between the second and fourth particle size fractions, having for lower limit d5 the upper limit D2 of the second particle size fraction, and having for upper limit D5 the lower limit d4 of the fourth particle size fraction, wherein the width of the fifth particle size fraction is greater than 20% of the upper limit D4, wherein the fifth particle size fraction has a weight relative to the weight of the aggregate such that

11. The coated material according to claim 1, wherein the proportion by weight of the hydrocarbon binder in the coated material is at most equal to 4.5%.

12. A pavement comprising at least one base layer or binder layer comprising a coated material according to claim 1.

13. A method for producing a coated material for a base layer or binder layer for road or highway pavement, or for industrial, port, or airport platforms, or for a supporting layer for railroad tracks,

said coated material being composed of aggregate mixed with at least one hydrocarbon binder, wherein the aggregate comprises a granular structure comprising several particle size fractions d/D, each particle size fraction being defined by a lower limit and an upper limit,

said method comprising the following steps, in any order:

a—

providing particles of a first particle size fraction d1/D1,

b—

providing particles of a second particle size fraction d2/D2, said first and second particle size fractions being separated by a third particle size fraction d3/D3 having as lower limit d3 the upper limit D1 of the first particle size fraction, and having as upper limit D3 the lower limit d2 of the second particle size fraction, wherein the third particle size fraction has a ratio of the weight relative to the weight of the aggregate, wherein the width of the third particle size fraction D3−

d3, defining a relative width (D3−

d3)/D2 in relation to the upper limit of the second particle size fraction, said relative width being greater than 20% of D2, wherein the ratio between the weight ratio of the third particle size fraction and its relative width is less than 0.4, which is;

14. The production method according to claim 13, wherein the first and second particle size fractions comprise a proportion of recycled aggregate, and wherein the total hydrocarbon binder comprises a portion of new hydrocarbon binder and a portion of hydrocarbon binder issuing from recycled aggregate.

15. The production method according to claim 13, additionally comprising the following steps:

e—

the coated material is spread on a surface,

f—

said coated material is compacted,

by means of which the coated material comprises a void content of less than 10%,

possibly less than 8%, and preferably less than 6%, and by means of which the modulus of rigidity of the coated material is greater than 9000 MPa at a temperature of 15°

C. and at a frequency of 10 Hz, and the fatigue resistance of the coated material is greater than 90 microstrain at a temperature of 10°

C. and at a frequency of 25 Hz.