US3529517A

US3529517A - Marked roadway and method of making the same

Info

Publication number: US3529517A
Application number: US747692A
Authority: US
Inventors: Gordon M Liddle; Frank L Christensen
Original assignee: Christensen Diamond Products Co
Current assignee: Norton Christensen Inc
Priority date: 1968-07-25
Filing date: 1968-07-25
Publication date: 1970-09-22
Anticipated expiration: 1987-09-22
Also published as: DE1926281A1; FR2013639A1; GB1216430A

Description

United States Patent [72] Inventors Gordon M. Liddle Murray; Frank L. Christensen, Salt Lake City, Utah [21] Appl. No. 747,692 [22] Filed July 25, 1968 [45] Patented Sept. 22, 1970 [73] Assignee Christensen Diamond Products Company Salt Lake City, Utah a corporation of Utah [54] MARKED ROADWAY AND METHOD OF MAKING THE SAME 13 Claims, 4 Drawing Figs.

[52] U.S. Cl 94/1.5, 94/22, 94/33, 299/39 [51] Int. Cl E01c 23/16 [50] Field of Search 9411.5, l;2 99/39;94/31 ,33,45,22

[56] References Cited UNITED STATES PATENTS 1,698,594 1/ 1929 Hoff 94/ 1.5 2,112,489 3/1938 Heltzel 94/45 6/1941 Tyson 299/39X 2,673,725 3/1954 Coates 299/39 2,855,189 10/1958 Lewis 299/39 3,232,187 2/1966 Brigham 94/1.5 3,396,639 8/1968 Lemelson 94/ 1.5 FOREIGN PATENTS 564,507 2/1958 Belgium 94/1.5

OTHER REFERENCES Proceedings of Highway Research Board, June 24, 1938, P s 3 Primary Examiner-Jacob L. Nackenoff Attorney-Bernard Kriegel side of the roadway for facilitating drainage during inclement weather.

Patented Sept. 22, 1970 3,529,517.

Sheet 1 of2 i m 4 A Ciro/200M M. Ii /001.5

E li emvxl Cq/e/s rs/vss/v Iv vEA/ToeS.

Patented Sept. 22, 1970 I/vvE/vro/es.

aM/ W The stripes or other markings on highways and other roads, which are employed to designate the center of the roadway or lanes for the passage of traffic thereon, pose problems respecting visibility of the markings or stripes. on the one hand, and durability of such markings or stripes, on the other hand.

In inclement weather. and particularly during the twilight or night hours, the usual roadway markings and stripes which designate the lanes of traffic, as well as the middle of the roadway or the sides thereof, are frequently not clearly visible. This is particularly true when the stripes or markings are beneath a layer of water during and following rainfall. In order to avoid the lack of visibility of the usual stripes and markings formed by the application of reflective coatings to the roadway surface, elevated reflectors may be employed, but such reflectors are not practical in certain geographical areas where accumulated snow on the roadway requires the use of road scraping equipment in order to open the roadway to the passage of vehicular trafiic.

Moreover, the provision of a suitable reflective coating for use in the striping or marking of roadways, which coating will stand heavy vehicular traffic, has long been a problem, inasmuch as the usual paint or other reflective coating material rapidly wears away, thereby requiring substantial expenditures in the maintenance of the roadway markings and stripes.

With the foregoing problem in view, the present invention provides a roadway having stripes or other markings thereon and a method of forming stripes or other markings in roadway surfaces, which stripes or-markings are more readily visible during the period that the ordinary stripes or markings on highway surfaces are not clearly visible due to poor lighting, particularly when water is on top of the reflective stripes or markings during inclement weather.

The present invention also provides a roadway having stripes or markings thereon and a method of forming such stripes or markings, which are more durable than the conventional surface stripes or markings heretofore employed on roadways.

More particularly, the present invention contemplates the formation of parallel ridges and intervening spaces extending along the roadway in the traffic supporting surface, at least the side walls of the ridges defining the intervening grooves or valleys having reflective paint or coating material applied thereto, and the crest of the ridges also being coated in a specific sense, so that the reflective coating is clearly visible to a motorist, but the major extent of the coated area is recessed beneath the traflic bearing surface of the highway or roadway so as to be protected from the usual wear caused by heavy vehicular trafiic.

The roadway and the method of the present invention also contemplate the formation of drain channels or grooves extended transversely of the ridges and intersecting the grooves defined between the ridges so as to effectively drain off water from the striped or marked regions of the roadway to the low side of the roadway, thereby enhancing visibility of the roadway markings or stripes during inclement weather.

Inasmuch as the stripes or markings in the roadway made in accordance with the present invention are substantially recessed, or at the peaks of the ridges do not project above the nonnal traffic supporting roadway surface, the roadway may be readily scraped by the usual road scraping equipment required to clear highways of snow and ice, in certain geographical areas where deposits of snow and ice on the roadway pose problems.

More specifically, the invention contemplates forming in a roadway surface a series of parallel grooves and ridges by milling the grooves, employing a milling cutter which may be of the type involving a rotatable milling cutter having diamonds embedded about the periphery of the milling cutter on ridges and in valleys of the milling cutter, which, upon revolution of the milling cutter and travel of the cutter along the roadway, will form mating valleys and ridges in the roadway surface, the side walls of the ridges of the milling cutter defining the grooves therebetween being disposed at an angle so as to provide in the roadway ridges having convergent side walls forming the valleys therebetween, so as to present laterally projecting surfaces to which the reflective coating material may be applied, and whereby a clearly visible road marking will be provided.

This invention possesses many other advantages and has other purposes which may be made more clearly apparent from a consideration of a form and method embodying the invention. This form and method are shown and described in the present specification and in the drawings accompanying and constituting a part thereof. They will now be described in detail, for the purpose of illustrating the general principles of the invention; but it is to be understood that such detailed description is not to be taken in a limiting sense, since the scope of the invention is best defined by the appended claims.

Referring to the drawings:

FIG. 1 is a view showing in perspective a section of roadway having markings applied thereto in accordance with the invention;

I FIG. 2 is a fragmentary view in vertical section, and on an enlarged scale, as taken on the line 22 of FIG. l;

' are the valleys 3, so as to effectively provide a stripe which, in-

FIG. 3 is a fragmentary view in vertical section, and on an enlarged scale, as taken on the line 3-3 of FIG. 1; and

FIG. 4 is a view corresponding to FIG. 2, but illustrating a modified roadway construction.

As seen in FIG. I, the invention involves the production of a roadway, generally denoted at R, and including a suitable road bed B and surface material S composed of concrete, or the like. The surface material S provides a traffic bearing surface T, which, in accordance with standard practices, should be formed on a suitable grade, as indicated by the angle A, so as to enable lateral drain-off of water from the traffic supporting surface T of the roadway during inclement weather. Extended along the roadway are markings in the form of stripes I, which typically would define the center of a roadway and/or desired traffic lanes along the roadway between which the vehicles are to travel. Such stripes l are generally in accordance with prior practices provided by the simple application of a stripe of reflective coating material or paint to the traffic supporting surface T at desired locations.

However, traffic changing of lanes must cross over the stripes 1, and in areas of heavy traffic, the stripes are, therefore subjected to severe wear. On the other hand, where such stripes designate stop lines or cross traflic lines, each and every vehicle passing over the roadway surface T must also pass over the marking stripes so that the wear problem is, perhaps, accentuated.

In the event that the road surface T is grooved by the use of milling cutters of the conventional diamond or saw types to smooth out surface irregularities and enhance traction, the 55' ridges and grooves are narrow or closely spaced so that paint stripes applied to such surfaces are not significantly protected or more visible in inclement weather.

However, in accordance with the present invention, the stripes 1 comprise a series of laterally spaced, parallel ridges 2 and intervening valleys 3. As best seen in FIG. 2, the ridges have crests 2a which project substantially to the plane of the traffic supporting surface T, whereby to afford support for vehicle tires passing over the stripes, so that the tendency to cause erratic vehicle travel will be eliminated. Moreover, in the embodiment of FIG. 2, the ridges 2 are arcuate in fonn, as

cross-section, is sinuous. This sinuous form of the adjacent ridges and valleys provides side walls 2b on the ridges, which, essentially, are divergent relative to one another, but convergent with the adjacent sidewall of the adjacent ridge so as to provide substantial lateral surface projection for the application of a coating of reflective paint or other material, as generally denoted at 4. I i I As vehicular traffic passes over the stripes defined by the ridges 2 and valleys 3, the coating at the crest 2a of the ridges is subjected to the maximum wear. but the side walls or flanks 2b of the ridges 2, being recessed below the normal traffic supporting surface T, are protected from such wear and, therefore, will endure for substantially greater period of time than would the usual stripe or marking applied directly to the surface T.

In order to prevent the stripes 1 from being obscured during periods of poor visibility, for example. during the twilight hours in inclement weather, when water may be upon the surface of the roadway. lateral drain channels are provided at appropriate spaced locations longitudinally of the stripes 1, these lateral drain channels 5 having a base 6 which is preferably as deep as the valleys 3, so that the drain channels 5 extend laterally through each of the ridges 2 and intersect each of the valleys 3, In addition, the drain channels 5, as seen in FIG. 3, extend laterally past the marginal valleys and, more particularly, the drain channels include an outlet portion 5a which merges with the traffic supporting surface T of the roadway downgrade from the lowest of the valleys 3. The base 6 of the drain channels 5 also is at an incline relative to the horizontal plane as represented by the angle C as seen in FIG. 3, whereby water from the valleys3 may quickly drain off laterally through the drain channels 5 in the direction of the nonnal roadway grade.

Referring now to FIG. 4, a modified roadway construction is shown in which the ridges 2 are of greater lateral extent than in the previously described embodiment. and include a flat crest surface 2a extended laterally substantially in the plane of the traffic supporting surface T of the roadway. In this embodiment, the valleys 3 are defined by opposing angular side walls 2b, as in the previously described embodiment; and, as in the previously described embodiment, the roadway is provided with lateral drain channels 5 so as to drain the surface water from the valleys 3, such drain channels traversing the ridges to establish communication with the valleys 3. Likewise, a reflective paint or other coating 4 is applied to the ridges and in the valleys. In this embodiment, the flat crests 2a have greater lateral extent in the plane of the road surface T than the crests of the first described embodiment, so as to afford better engagement with vehicle tires and reduced tendency to cause erratic wheel movements.

In the practice of the present method of forming highway markings or stripes, the lateral drain channels 5 may be milled or formed in the surface T either prior to or subsequent to the milling or forming of the ridges 2 and grooves or valleys 3. Also, these drain channels 5 may be formed either prior to or following the application of reflective paint or other coating material to the ridges and grooves by any of the conventional methods.

While one specific form of lateral drain channel 5 has been illustrated, it is apparent that other specific forms of drain channels may be employed. For example, the drain channels may be formed with the same milling cutter employed to form the stripes I, and in such a case, the valleys or grooves 3 cumulatively would provide substantial lateral drain flow area. Other forms of drain channels, as well as other specific shapes of valleys 3 and ridges 2, will be apparent.

We claim:

1 1. In a concrete roadway having a normal vehicle supporting surface and a traffic lane extending along said surface, said concrete roadway having a lane marking defining a side boundary of said lane, said marking comprising valleys formed in the concrete and extending downwardly of said surface and longitudinally of said lane and parallel to the center line of said lane, said valleys being separated by intervening laterally spaced concrete ridges integral with the concrete roadway and extending longitudinally of said lane and parallel to the center line of said lane, said ridges commencing at said normal vehicle supporting surface and extending downwardly thereof to define said valleys therebetween. the opposing side walls of ridges forming each intervening valley converging downwardly toward each other to the bottom of each valley,

and a reflective coatin on at least the side walls of said ridges. 2. A roadway as de med in claim I, wherein said ridges and valleys are of transversely sinuous form.

3. A roadway as defined in claim 1, wherein said ridges have flat upper surfaces.

4. A roadway as defined in claim I, wherein a drain channel extends laterally through said ridges and intersects said valleys.

5. A roadway as defined in claim 1, wherein said coating is also on the crests of said ridges.

6. A roadway as defined in claim 1, wherein said coating is also on the crests of said ridges and in the bottoms of said valleys.

7. A roadway as defined in claim 1, said roadway having a drain channel extending laterally across said valleys and ridges and having a bottom at least as deep as the bottoms of said valleys.

8. A roadway as defined in claim 1, said roadway having a drain channel extending laterally across said valleys and ridges and having a bottom at least as deep as the bottoms of said valleys, the bottom of said drain channel feathering out to said normal vehicle supporting surface in laterally spaced relation to said ridges and valleys.

9. The method of providing a lane side boundary marking in a hard concrete roadway having a normal vehicle supporting surface and a traffic lane extending along said surface, comprising cutting spaced, longitudinally extending parallel valleys in said hard concrete roadway extending downwardly from said normal surface and parallel to the center line of said lane to provide intervening parallel ridges extending longitudinally of said lane and parallel to the center line of said lane, said valleys being cut to provide side walls of said ridges forming each intervening valley that converge downwardly toward each other to the bottom of each valley, and then applying a reflective coating on at least the converging side walls of said ridges.

10. In a method as defined in claim 9; said valleys being cut to provide said intervening ridges which commence at said normal vehicle surface and extend downwardly therefrom.

II. In a method as defined in claim 9; cutting a drain channel in said hard concrete roadway extending laterally across said ridges and valleys with the bottom of said channel at least as deep as the bottoms of said valleys.

12. In a method as defined in claim 9; also applying said reflective coating to the crest of said ridges.

13. In a method as defined in claim 9; said valleys and intervening ridges being cut by forcing rotating cutter means against the roadway while moving said cutter means longitudinally along said roadway.