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Title:
METHOD OF REPAIRING DEFECTS OF A WEARING COURSE OF ROAD SURFACE, PARTICULARLY PERMANENT DEFORMATIONS OF ITS SURFACE AND ROUGHNESS LOSS
Document Type and Number:
WIPO Patent Application WO/2004/067847
Kind Code:
A1
Abstract:
A method of repairing defects of a wearing course of a road surface, particularly permanent deformations and roughness loss characterized in that a noisy profile with grooving formed with parallel longitudinal grooves is first cut with a cutter across at least one half of a road lane; simultaneously the deformed road cover pressed out above the level of the surface of the wearing course is removed and the part of the undamaged and less travelled wearing course is also cut with the same cutter, but not more than up to 1/2 of its thickness h, then edges of the grooves of the noisy profile are chamfered. A draining profile with grooving formed with parallel grooves having a quadrangle shape in their cross section is cut with a spacing of 0.5 m up to 50 m, wherein the grooves are made at the angle a 10 ° - 89° to the longitudinal axis of the road, and then a protective coating with penetration materials is applied onto the already treated wearing course.

Inventors:
RUZICKA MOJMIR (CZ)
Application Number:
PCT/CZ2004/000002
Publication Date:
August 12, 2004
Filing Date:
January 21, 2004
Export Citation:
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Assignee:
BLASTRAK MORAVA SPOL S R O (CZ)
RUZICKA MOJMIR (CZ)
International Classes:
E01C7/18; E01C11/24; (IPC1-7): E01C11/24; E01C7/18
Foreign References:
CA2306690A12001-10-26
DE2063769A11972-07-06
US5180428A1993-01-19
Other References:
"Die vielseitigen Anwendungen von Kleinfräsen bis 1m Arbeitsbreite", 2001, WIRTGEN GMBH, GERMANY, XP002279439
Attorney, Agent or Firm:
Kendereski, Dusan (Lidicka 51, Brno, CZ)
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Claims:
PATENT CLAIMS
1. A method of repairing defects of a wearing course of a road surface, particularly permanent deformations and roughness loss characterized in that a noisy profile with grooving formed with parallel longitudinal grooves to the longitudinal axis of the road is first cut with a cutter across at least one half of a lane and simultaneously a mixture of a road cover pressed out above the level of the surface of the wearing course is removed, then the part of the undamaged and less travelled wearing course is also cut with the same cutter, but not more than up to 1/2 of its thickness h, then edges of the grooves of the noisy profile are chamfered and then a draining profile with grooving formed with parallel grooves having a quadrangle shape in their cross section is cut with spacing of 0.5 m up to 50 m, where the grooves are made at the angle a 1°89° to the longitudinal axis of the road and then a protective coating with penetrating materials is applied onto the already treated wearing course.
2. The method of repairing defects of the wearing course of the road surface, particularly permanent deformations and roughness loss according to Claim 1 characterized in that the noisy profile with grooving formed with parallel longitudinal grooves to the longitudinal axis of the road is first cut with the cutter across at least one half of the lane and simultaneously the mixture of the road cover pressed out above the level of the surface of the wearing course and the part of the undamaged and less travelled wearing course is removed, but not more than up to 1/2 of its thickness h, then edges of the grooves of the noisy profile are chamfered and then the draining profile with grooving formed with parallel grooves having a quadrangle shape in their cross section is cut with spacing of 0.5 m up to 50 m, where the grooves are made at the angle a 1°89° to the longitudinal axis of the road and then the protective coating with penetrating materials is applied onto the already treated wearing course.
3. The method of repairing defects of the wearing course of the road surface, particularly permanent deformations and roughness loss according to Claim 1 characterized in that a profile with grooving formed with parallel longitudinal grooves to the longitudinal axis of the road is first cut with the cutter across at least one half of the lane and simultaneously the mixture of the road cover pressed out above the level of the surface of the wearing course and the part of the undamaged wearing course are removed, but not more than up to the depth of 1 cm of the undamaged wearing course, then edges of the grooves in the locations of the noisy profile are chamfered and then the protective coating with penetration materials is applied onto the already treated wearing course.
4. The method of repairing defects of the wearing course of the road surface, particularly permanent deformations according to Claim 1 characterized in that the noisy profile with grooving formed with parallel longitudinal grooves to the longitudinal axis of the road is first cut with the cutter across at least one half of the lane on the undamaged and less travelled wearing course, namely not more than up to Y ? of its thickness, and then the protective coating with penetration materials is applied onto the already treated wearing course.
5. The method of repairing defects of the wearing course of the road surface, particularly permanent deformations and roughness loss according to Claim 1 characterized in that cutting of the noisy profile with grooving formed with parallel longitudinal grooves to the longitudinal axis and removing of the mixture of the road cover pressed out above the level of the surface of the wearing course and removing of the part of the undamaged and less travelled wearing course, but not more than up to % of its thickness h, is performed in the individual stages.
6. The method of repairing defects of the wearing course of the road surface, particularly roughness loss according to Claim 3 characterized in that the profile with grooving formed with parallel longitudinal grooves to the longitudinal axis of the road is first cut with the cutter across at least one half of the lane and simultaneously the part of the undamaged wearing course is removed, but not more than up to the depth of 1 cm, then the draining profile with grooving formed with the parallel grooves having the quadrangle shape in their cross section is cut with spacing of 0.5 m 50 m where the grooves are made at the angle a 1°89°.
Description:
METHOD OF REPAIRING DEFECTS OF A WEARING COURSE OF ROAD SURFACE, PARTICULARLY PERMANENT DEFORMATIONS OF ITS SURFACE AND ROUGHNESS LOSS Technical Field The present invention relates to a method of repairing defects of a wearing course of road surface, particularly permanent deformations of its surface and roughness loss.

Contemporary Prior Art Road structures being under various climatic conditions and loading show damage mechanisms depending on their properties. The damages and defects mentioned occur both regularly and randomly. Said negative phenomena occur on roads particularly due to the incorrect technology used during road construction, or they are caused by traffic, particularly haulage, where motor vehicles, primarily overweighed ones, wear excessively the surface of the wearing course of a foundation surface. The events mentioned result in the deformation of the wearing course manifested by such defects as permanent deformations of the road surface or its roughness loss. The defects belonging to the group of deformations present on the road surface are particularly as follows : ruts, longitudinal waves, uneven bumps and bumps formed due to previous repairs. The defects belonging to the group of roughness loss are particularly as follows : loss of a surface microtexture and loss of a surface macrotexture.

Each of the defects mentioned caused by vehicle traffic is important taking into account the operating functions of the road and its load-bearing capacity. Defects results in impairments appearing on the road structure and have negative impact on the fast- flowing traffic. All of them are costly taking into account losses due to traffic accidents, costs demanded for road maintenance, repair and, if necessary, reconstructions.

The term"roughness loss"means the loss of sufficient sliding friction as the resistance caused by the relative movement of a tyre surface on a road surface during breaking or acceleration, and/or when changing a vehicle direction. Resistance then depends on the release of particles from both surfaces. The richer is a pattern on both surfaces and the sharper and firmer is a material present on a surface of a wearing

course of a foundation surface, the higher and more permanent friction could be expected. Loss of the roughness of the surface of the wearing course of the foundation surface occurs either due to the process during which of a smooth surface without protruding grains of aggregates is formed, which results in the loss of the surface macrotexture, or due to the process during which the aggregates grains are smoothed due to their contact with tyres, which results in the loss of surface microtexture. Both events mentioned result in the loss of sliding friction. Loss of the surface macrotexture influences, in addition, the friction at high speeds and thus supports loss of the surface microtexture at speeds up to 60 km/h. The event of loss of the surface macrotexture is connected both with the process during which a bond is protruding onto a road surface (when coating is used), or the process during which a mastic asphalt protrudes onto a surface. Both mechanisms occur obviously due to the incorrect technology used during road construction but they can be also caused by the random variability in the foundation properties, composition of the mixture used, etc. The event of loss of the surface microtexture is connected with the unsuitable rubbing down property of aggregates (e. g. easily rubbing down aggregates as limestone and slate or already rubbed down grains of aggregates-so called mined coarse aggregates-are used).

Wearing courses of all road types, particularly asphalt pavements, are susceptible to permanent deformations. Surface layers bonded with mastic asphalt have the feature of the bond that behaves as a hard and brittle material at low temperatures (according to the asphalt type at the temperatures between 5 °C and 10 °C) or at high rates of loading (where the temperature could be by 20 °C higher). On the contrary, it behaves as a thick liquid at higher temperatures (according to the asphalt type used at the temperatures between 40° C and 65° C) and the long-term load. The aggregates are either glued together with the bond or are embedded in it (are floating in it). The asphalt mixtures are elastic at high rates of loading-they can be compared to concrete). But at high temperatures, or when vehicles move at slow speeds or stop, the aggregates grains start to move one another, and the asphalt mixture moves from the point of the concentrated pressure to points free of such action. The asphalt mixture can be compared to thick dough in this case. Depressions are caused by insufficient resistance of the surface layers against formation of permanent deformations. Said events are caused by the use of mined aggregates, unsuitable grain size of aggregates, high asphalt content or use of asphalt types featuring with higher penetration.

According to the loading type, depressions occur at locations where vehicles stop, e. g. bus or trolleybus stops, while ruts are formed in tyre contact areas of heavy good vehicles. The depressions in tyre contact areas of lorries are obviously 60 cm-80 cm wide and 1 cm-5 cm deep. They are formed obviously in locations of intensive, slow and stopping traffic, in creeper lanes or on local roads, and can be observed on speedways and expressways. They are often continuous, being of the length of even several dozens of kilometres. The wearing course of draining bituminous carpets or mastic bituminous carpets or highway asphalt mastics is obviously up to 40 mm thick. Its thickness reaches 50 mm and sometimes up to 60 mm in case of asphalt concretes.

The deformation increase ceases gradually after the first 1-3 years in case of the road defect type mentioned in the first instance. In the second instance, if it reaches the unsuitable level, it will develop up to the enormous depths exceeding 20 mm. The risk of aquaplaning accompanied by a skid is rather high in such cases.

In normal practice, repairs are performed depending on the depth of depressions or ruts. In the first instance, when their depths are rather small, the depressions or ruts are filled with a micro-carpet or a thin bituminous carpet if the increase of rut depth has been already stopped (after about 8 years of use up to the depth of 12 mm). In the second instance, all asphalt layers causing the permanent deformation are replaced (layers are cut and replaced at the depths of 50 mm-120 mm, or even deeper in exceptional cases; the mined aggregates and the foundation made of coated materials are used).

The main aspect that should be taken into account when planning any repair is the financial possibilities of a road keeper. The unwritten rule"wait till spring"has been always kept; it means that only those road sections where traffic should have been otherwise stopped are repaired. This approach, nevertheless, contests the principles stating that if the damage is maintained at its early stage, obviously during the first year, the costs for its repair used to be the lowest ; on the other hand, as time rolls on, costs increase from 100.-CZK/m2 up to 500.-CZK/m2 and even more.

This invention relates to the method of repair of the defects mentioned above that guarantees effective, cheap and quick repair of the defects mentioned without the need to interrupt traffic. A road repaired according to the method mentioned above will feature with far higher safety traffic parameters, even if compared with a completely new road.

Summary of the Invention The above-mentioned disadvantages are eliminated by the method used for repairing the defects of a wearing course on a road surface, particularly permanent deformations of its surface and roughness loss characterized in that a noisy profile with grooving formed with parallel longitudinal grooves to a longitudinal axis of a road is first cut with a cutter across at least one half of a road lane while a mixture of a cover forced out above the level of the wearing course surface is removed; then the part of the undamaged and less travelled wearing course is cut with the same cutter, namely, not more than up to one half of its thickness h ; then edges of the grooves of the noisy profile are cut with the cutter; then a drainage profile with grooving formed with parallel grooves having the quadrangle shape in their cross section where the grooves are made at the angle a 1°-89° to the longitudinal axis of the road is cut with spacing of 0.5 m-50 m; then the protective sprayed coating with penetrating materials is applied on the already treated (cut) wearing course.

The main advantage of the method claimed in the subject-matter of the patent consists in the fact that, after the wearing course of the road is repaired by cutting, the mixture of the cover forced out of the tyre contact areas is removed and the cover is overall levelled which supports also better travel comfort. At least one half of the lane is always cut. Blisters, longitudinal waves, ruts and uneven bumps present in the wearing course can be removed using the method as above. Cutting with the cutter fitted with a levelling profile bevels advantageously enables chamfering of edges of the longitudinal grooves, which results in that the surface treated has smooth grooving that is less noisy. The surface finished accordingly eliminates the side run-out of vehicles.

For example, unevennesses occurring above the level of the surface of the wearing course of the surface road during rut repairing are removed by cutting. After repairing is finished, the hollow bottoms of longitudinal ruts remain undamaged. Only the mixture of the cover forced out of the tyre contact areas and the part of the wearing course not more than up to 1/4-1/2 of its thickness h are removed by cutting. The wearing course present at the lowest rut locations, i. e. at the locations of their highest loading, is not affected at all by cutting and keeps all parameters of the initial wearing

course, which increases its service life. The wearing course thus shows no reduction in the location that should result in potential damage of the road. Because the height h of the wearing course is obviously 5 cm, this method of repairing can be applied providing that 1/2 of the wearing course is removed for at least once or 1/4 of the wearing course is removed for not more than twice.

The longitudinal ruts repaired as described above, which depth is reduced to not more than Y2-1/10 of their initial depth k (before the repair is performed by the method claimed in the subject-matter of the invention) can be then naturally used for salt brine collection resulting in formation of safe surface after chemical treatment of the road. Salt brine enhances dissolution of icing and/or snow, which results in formation of salt brine.

Salt brine is splashed out with vehicle tyres into close environment where it is retained in the longitudinal grooves. Then it flows back (in order to be used for several times) into the lowest locations of the longitudinal ruts or hollows as it increases in bulk with water from snow. Excessive volume of salt brine results in its overflow from the longitudinal grooves into the longitudinal ruts.

All the conditions mentioned above support longer movement of salt brine on the road surface which results in its longer chemical reaction. Salt brine then flows back to the lowest locations of the longitudinal ruts or hollows due to its increasing volume.

Excessive volume of salt brine results in its overflow from the longitudinal grooves into the longitudinal ruts. Such fully automatic flow-back replaces activities of people, machines and salt during highway winter maintenance.

If the longitudinal grooves without ruts are only present on the road surface, the longitudinal grooves will retain salt brine. Salt brine is kept in the longitudinal grooves as in a special"reservoir" ; only after its volume starts to increase gradually due to rainfall or snowfall, it will return to the locations on the road surface and only then, it leaves the road surface. Due to the process described the vehicle tyres can move on a surface being free of any icing; the critical locations turn then safe first and the physical relations themselves support human activities aimed at practicability of the roads in winter.

On the other hand, in summer, during heavy rain, it is important to remove large volumes of water from the road surface as quickly as possible and thus eliminate aquaplaning. Both types of grooving, namely, both the parallel longitudinal grooves and skewed grooves cut into the wearing course of the road with spacing of 0.5 m up to 50 m at the angle of 45° in the traffic

direction are used for this purpose. It has been found out that said both types of grooves formed in the wearing course eliminate formation of water mist due to the lifting force of tyres as the vehicles move onto the smooth road surface. Formation of water mist on the road is undesirable because it reduces visibility of car drivers travelling in convoys.

Another advantage of the method mentioned consists in the fact that-after the sharp edges are cut down-the surface of the wearing course is smoother and thus less noisy; in addition, water is removed very well from the surface of the wearing course of the road treated as mentioned.

In comparison with the currently used methods of repairs, the method claimed in the subject-matter of this invention is twice up to four times cheaper. It can be advantageously performed all the year round including the winter season providing that the road is free of snow. Its use has the instant effect to traffic safety. In addition, the demanded waste material is formed during cutting of the wearing course that can be processed to recyclate or, after the relevant treatment, can be used as a fine filling (aggregates) directly into pavements. The process as above could reduce costs for the road repairs by up to 10%.

The method used for repairing the wearing course claimed in the subject-matter of this patent reduces also significantly costs for winter maintenance because salt brine is kept for four times up to ten times longer not only on the rough surface of the wearing course but also in the longitudinal grooves and rut bottoms, if compared with the new smooth surfaces. This reduces costs for winter maintenance, both as far as the frequency of necessary actions and quantity of salt consumed. The method as above is also important from the point of view of increased traffic safety on bridges having other temperature regimen than the rest of roads.

After the ruts are repaired using the method claimed in the subject-matter of the invention, vehicles could move again both in the locations with the longitudinal ruts and on the grooved roughed surface of the pavement wearing course. If the vehicle goes into a skid due to water being retained in the longitudinal rut, it is caught with its tyres on the surface of the wearing course fitted with grooving and thus the driver can line up the vehicle and continue riding.

The protective sprayed coating applied after cutting seals naturally all microcracks and bonds the cracks present in the road surface. Traffic safety is then increased due to

quicker water drainage. Moreover, the penetrating material applied reinforces the surface of the repaired wearing course. When the water-proof penetrating materials are used, water cannot penetrate into the road structures and it thus supports its longer service life.

The noisy profile fitted with grooving formed with the longitudinal grooves can be also advantageously cut into the undamaged and less travelled locations of the wearing course and the protective sprayed cover can be then applied. This method of the repair of the wearing course can be advantageously used in dangers locations where curves and hills are present, and on bridge heads. Increased profile noisiness alerts drivers to dangerous locations of frequent accidents that results in speed reduction, e. g. when driving through curves. In this particular event, noise elimination seems to be the second-rate consideration.

Description of the Drawings A method of repairing defects of a wearing course of road surface, particularly permanent deformations of its surface and roughness loss according to the invention, will be clarified by way of drawings where Fig. 1 is a wearing course before the mixture forced out of tyre contact areas is cut; Fig. 2 is a profile of the wearing course with edges and longitudinal grooves 10 and the bottom of a rut after the surface were cut with a cutter having a fine profile; Fig. 3 is the profile of the wearing course with cut edges and longitudinal grooves 12; Fig. 4 is a reduction of the rut height; Fig. 5 is the plan of one lane 15 with ruts and a draining profile with grooving formed with parallel grooves having the quadrangle shape in their cross section where grooves are made at the angle a = 45° to the longitudinal axis of a road; Fig. 6 is a protective sprayed cover appled on to a surface of the treated wearing course; Fig. 7 is the rut formed with vehicle tyres in the wearing course of the road surface; Fig. 8 is a longitudinal wave formed with vehicle tyres in the wearing course of the road surface; Fig. 9 are uneven bumps present on to the wearing course 1; Fig. 10 is loss of microtexture occurring in the wearing course of the road surface due to the process during which grains or aggregate elements present on the surface of the wearing course are rounded and their surface smoothed; Fig. 11 is loss of macrotexture in the wearing course of the road surface due to the process during which a bond or mastic asphalt protrude onto the

surface of the wearing course; Fig. 12 is the detail of the draining profile with grooving formed with parallel grooves having quadrangle shape in their cross section.

Description of the Preferred Embodiment The method of repairing defects of a wearing course of road surface, particularly permanent deformations of its surface and roughness loss according to the invention will be clarified by means of several advantageous embodiments of repairs performed, e. g. longitudinal waves, ruts, uneven bumps and loss of surface roughness.

The method proposed, used for repairing defects, consists generally of four stages apparent from Fig. 1, Fig. 2, Fig. 3, Fig. 5, and Fig. 6. In the first stage, a noisy profile 7 formed by paralelly arranged longitudinal grooves 12 having e. g. a triangular shape in their cross section, is cut with a cutter fitted with a fine profile across at least one half of a lane 15. Simultaneously with cutting of the noisy profile 7, a mixture 4 of a road surface forced out above the level of the surface of a wearing course 1 is removed together with the part of the undamaged and less travelled wearing course 1, but not more than up to 1/2 of its thickness h. In the second stage, edges 10 of the longitudinal grooves 12 of the noisy profile 7 are chamfered with the cutter fitted with a shaping profile in order to form a noiseless profile 9. In the third stage, depending on the particular landscape relief, a draining profile 14 with grooving 11 formed with parallel grooves 16 having a quadrangle shape in their cross section is cut with spacing of 0.5 m - 50 m, where grooves 16 are made at the angle a 1°-89° to the longitudinal axis 13 of the road. In the fourth stage, in order to prolong service life of the wearing course 1 and to support quicker water draining from the road surface, the protective cover is sprayed onto the wearing course 1 being already treated with cutting. The procedure mentioned can be on demand repeated for at least once on the already cut wearing course 1, and some of the stages as above can be omitted depending on the particular defect type.

The procedure for rut repairing is described in the example No. 1. Ruts 2 obviously 60 cm-80 cm wide, as it is apparent from Fig. 1, are formed in the tyre contact areas of lorries. They are formed in locations with intensive, slow and stopping traffic, particularly in creeper lanes and on local roads. The defect mentioned is caused by insufficient resistance of both the wearing course 1 and

a binding bottoming course 3 against the development of permanent deformations due to the use of mined aggregates, unsuitable aggregate graining curve, high asphalt content, and asphalt type of high penetration. Such defect is being developed for 1-3 years and the depth of a bottom 8 of the rut 2 can exceed 2 cm. The repair of the rut 2 according to the method proposed is performed in the following stages: In the first stage, the noisy profile 7 formed by longitudinal grooves 12 having the triangle shape is cut with a large road cutter fitted with a fine cutting profile in the direction 17 of a vehicle travel across the whole width of the road. Simultaneously, the mixture 4 of the road surface forced out of the tyre contact areas and the part of the wearing course 1 that was neither damaged nor travelled, is removed, but not more than up to 1/2 of its thickness h, i. e. up to 2.5cm. In the second stage, edges 10 of the longitudinal grooves 12 of the already cut noisy profile 7 are chamfered at the angle of ß 0°- 90 ° with a small flexible cutter, so called chipper, fitted with a shaping profile in order to eliminate both the noise on the road and the vehicle side run-out, as it is apparent from Fig. 3. In the third stage, the draining profile 14 formed with grooving 11 spaced 0.5 m-50 m, is cut while, as it is apparent from Fig. 12, grooving 11 is formed with parallel grooves 16 having a quadrangle shape in their cross section that are made at the angle a 45° to the longitudinal axis of the road, see Fig. 5. Skewed direction of grooves 16 is important to enable excessive water volume leave quickly the longitudinally cut grooves 12 and thus the entire road surface, see Fig. 5. In the fourth stage, after the service life of the wearing course 1 is prolonged and quicker water draining from the road surface ensured, as it is apparent from Fig. 6, the penetratinon is performed with materials on the base of silicon or with asphalt emulsion or with modified asphalt sprayed layer or acrylate or polymethylmetacrylate that penetrate after cutting into the depths up to 100 mm and seal the microcracks and connect cracks. Materials mentioned above penetrate not only into the surface of the wearing course but also into the deeper layers of the road surface and thus eliminate water penetration into the layers of the road surface and support its longer service life. This procedure can be, if necessary, repeated at least once on the already cut wearing course 1.

The procedure used for repairing of the longitudinal wave is described in Example No. 2. Longitudinal waves 5, as apparent from Fig. 8 used to occur on crossroads in front of stop lines. They are formed by transversal bumps apparent in many rows one another. The spacing between the longitudinal waves 5 is 50 cm. The longitudinal waves in lanes travelled by lorries are interrupted by ruts 2 with deep hollows. This defect is caused by insufficient resistance of asphalt layers on the road surface. i. e. both the wearing course 1 and the binding bottoming course 3, against permanent deformations. The longitudinal waves 5 are formed along the whole with of the lane when asphalt mixtures are pressed out of from under tyres of standing passenger cars. Repairs of the longitudinal wave 5 according to the method proposed can be advantageously performed in three stages only, because the stage used for cutting of the drainage profile 14 can be advantageously omitted. In the first stage, the noisy profile 7 with grooving 11 formed with the longitudinal grooves 12 having the triangular shape is cut in the travel direction 17 wiith a large road cutter fitted with a fine cutting profile. Simultaneously, the mixture 4 of the road surface forced out above the level of the wearing course and the part of the wearing course 1 that was not damaged and was travelled only a little is removed, but not more than up to 1/2 of its thickness h, i. e. up to 2.5 cm. In the second stage, edges 10 of the longitudinal grooves 12 of the already cut noisy profile 7 are chamfered at the angle of p 0°-90 ° with a small flexible cutter, so called chipper, in order to eliminate noise on the road, as it is apparent from Fig. 3. In the third stage, after the service life of the wearing course 1 is prolonged and quicker water draining from the road surface ensured, as it is apparent from Fig. 6, the penetratinon is performed with materials on the base of silicon or with asphalt emulsion or with modified asphalt sprayed layer or acrylate or polymethylmetacrylate that penetrate after cutting into the depths up to 100 mm and seal the microcracks and connect cracks. Materials mentioned above penetrate not only into the surface of the wearing course but also into the deeper layers of the road surface and thus eliminate water penetration into the layers of the road surface and support its longer service life. This procedure can be, if necessary, repeated at least once on the already cut wearing course 1.

The procedure intended for repairing of uneven bumps is described in Example 3.

An uneven bump 6, as it is evident from Fig. 9, is the surface unevenness occurring during normal maintenance performed when gritting or coating materials are appled. It occurs obviously sporadically on the limited spots of the wearing course or continuously in various widths. The method used for repairing of the uneven bump 6 can be advantageously performed in three stages only because for the case mentioned, the stage used for chamfering of edges 10 of the longitudinal grooves 12 of the noisy profile 7 may be omitted. In the first stage, the noisy profile 7 with grooving 11 formed with the longitudinal grooves 12 having the triangular shape is cut in the travel direction 17 across the whole width of the road with a large road cutter fitted with a socket adjusted for the fine cutting profile. Simultaneously, the identical procedure is used to remove the uneven bump 6 being above the level of the wearing course 1 together with the part of the wearing course 1 that was not damaged and travelled, but not more than to 1/2 of its thickness h, i. e. up to 2.5 cm. In the second stage, the draining profile 14 is cut by grooving 11 performed in the demanded frequency, e. g. 5 m, while-as it is apparent from Fig. 12-grooving 11 is formed with parallel grooves 16 having the rectangle shape in their cross section and made at the angle a 45° to the longitudinal axis of the road. Skewed grooves 16 are important because they enable draining of the excessive water from the longitudinally cut grooves 12 and thus from the whole road surface, see Fig. 5. In the third stage, after the service life of the wearing course 1 is prolonged and quicker water draining ensured from the road surface, as it is apparent from Fig. 6, the penetratinon is performed with materials on the base of silicon or with asphalt emulsion or with modified asphalt sprayed layer or acrylate or polymethylmetacrylate that penetrate after cutting into the depths up to 100 mm and seal the microcracks and connect cracks. Materials mentioned above penetrate not only into the surface of the wearing course but also into the deeper layers of the road surface and thus eliminate water penetration into the layers of the road surface and support its longer service life.

This procedure can be, if necessary, repeated at least once on the already cut wearing course 1.

The procedure used for repairing roughness loss of the wearing course is described in Example 4. The term"roughness loss"means the loss of sufficient sliding friction as the resistance caused by the relative movement of a tyre surface on a road

surface during breaking or acceleration, and/or when changing a vehicle direction.

Resistance then depends on the release of particles from both surfaces. The richer is a pattern on both surfaces and the sharper and firmer is a material on a surface of a wearing course of a foundation surface, the higher and more permanent friction could be expected. Loss of the roughness on the surface of the wearing course of the foundation surface occurs either due to the process during which of a smooth surface without protruding grains of aggregates is formed (which results in the loss of the surface macrotexture) or due to the process during which the aggregates grains are smoothed due to their contact with tyres (which results in the loss of surface microtexture). The defect mentioned above can be remedied using the method according to this invention where the profile with grooving formed with parallel longitudinal grooves is cut and simultaneously the mixture of the road surface forced out above the level of the surface of both the wearing course and the part of undamaged wearing course are removed, but not more than up to 1 cm of its thickness h. The service life of the wearing course is then prolonged and quicker draining of water from the road surface ensured. The protective coating with penetrating materials is then performed on the already treated (cut) wearing course.

Industrial Applicability Repairs of all defects according to this invention can be used for all types of roads showing longitudinal ruts, longitudinal waves, uneven bumps and surfaces. This supports considerably travel comfort and traffic safety while costs for winter maintenance are reduced considerably which, in turn, improves environmental conditions. The methods according to the invention can be also advantageously applied onto completely new surfaces of wearing courses to enhance surface roughness and sliding friction as well.




 
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