METHOD AND APPARATUS FOR BUILDING ROADS
United States Patent 3716302
A method and apparatus for building roads including the steps of dipping special corrugated units into cold asphalt, arranging the dip coated units into a generally flat, planar continuous reinforcement, and pouring paving material over and through said reinforcement to establish a reinforced pavement.
US Patent References:
Perforated or expanded sheet metal
Humphris - March 1929 - 1704608
Roadway and method of making the same
Sadtler - March 1929 - 1706077
Prefabricated runway construction
Robishaw - May 1953 - 2639650
Perforated or expanded sheet metal
Humphris - March 1929 - 1704608
Roadway and method of making the same
Sadtler - March 1929 - 1706077
Prefabricated runway construction
Robishaw - May 1953 - 2639650
Application Number:
05/170771
Publication Date:
02/13/1973
Filing Date:
08/11/1971
View Patent Images:
Export Citation:
Primary Class:
Other Classes:
52/671
International Classes:
E01C3/00; E01C11/16; E21D11/10; E01C11/00; E01C9/00
Field of Search:
94/2,3,4,22,8,7,23 52/671,672
Primary Examiner:
Byers Jr., Nile C.
Parent Case Data:
RELATION TO COPENDING APPLICATION
This application is a division of copending application Ser. No. 798,747, filed Feb. 12, 1969, now U.S. Pat. No. 3,601,945.
Claims:
I claim
1. An improved roadway construction comprising:
2. The roadway of claim 1, in which
3. The roadway of claim 1, in which
4. The roadway of claim 3, in which
1. An improved roadway construction comprising:
2. The roadway of claim 1, in which
3. The roadway of claim 1, in which
4. The roadway of claim 3, in which
Description:
This invention relates to a panel-like structural unit which is suitable for use as permanent formwork and as a means of reinforcement in concrete construction, for example, for lining tunnels, for making exposed ground safe and for building carriageways.
An object of this invention is to provide a structural unit which is readily mated with similar units.
According to the present invention, there is provided a panel-like structural unit particularly for use as permanent formwork and reinforcement in concrete constructions, said unit being formed with corrugations, at least one crest of which is depressed at intervals to form a row of pockets for receiving a connecting element extending longitudinally of the corrugations, whereby overlapping units are connectable, the pockets each decreasing in width, considered longitudinally of the corrugations, with increase in depth of the pocket.
When the edges of two units are overlapped, the pockets (formed both by the depressed portions and the portions of the crest intermediate the depressed portions) of the units mate together.
By virtue of the wedge form given to the pockets, the units mate readily both when the units are flat, and when they are deformed to construct an arch during tunnel construction.
Inter-engagement of the units in the overlap zone is additionally facilitated by the fact that the pockets are arched to reduce their width, for example being of U- or V-form cross-section.
According to another advantageous aspect of the invention, the edges defining the pockets merge substantially along a straight line with the troughs adjacent the crest or crests in which the pockets are formed. This simplifies manufacture of the unit because it is possible to use a tool simpler than that used for conventional units. At the same time, flexural strength is increased, thus enabling the units to be installed with greater unsupported lengths.
A particularly favorable cross-sectional form for the corrugations is obtained where the sides of the troughs include between them an angle of about 90°, because in this way the corrugations lie tightly adjacent one another in the overlap zone and offer particularly high resistance to pressure and tension.
The panel-like structural units of the aforementioned type have excellent strength properties and are easy to store, transport and handle.
It has now been found that the aforementioned structural units may also be used for the construction of carriageways, for example runways at airports, roads for tank traffic, and also for soil consolidation. The process which the invention provides to this end comprises immersing the units in cold asphalt, laying them as sheet-form reinforcement and covering them with the material forming the surface of the carriageway.
One embodiment of the process comprises covering the units with a mixed bitumen coating forming the surface of the carriageway. In another embodiment of the invention, the units are covered with grit and stones which are then sprayed with bitumen and rolled, after which the surface is prepared by gritting and rolling.
The invention is described in detail by way of example only in the following with reference to the accompanying drawings, wherein:
FIG. 1 is a front elevation of two structural units overlapping at the point at which they are joined.
FIG. 2 is a partial section through the units shown in FIG. 1 on the line I--I.
FIG. 3 is a front elevation of a modified embodiment of the structural unit.
FIG. 4 is a section through FIG. 3 on the line III--III.
FIG. 5 is a front elevation corresponding to FIG. 1 of a structural unit installed in an arched position, the arching running parallel to the rows of pockets.
FIG. 6 is a section through the unit shown in FIG. 1 which is arched about an axis extending transversely of the rows of pockets.
FIG. 7 is a partial section through a completed tunnel or gallery lining.
FIG. 8 is a longitudinal section through a joint between two overlapping structural units.
FIG. 9 is a plan view of the joint shown in FIG. 8.
FIG. 10 is a vertical partial section through a carriageway constructed in accordance with the process of the invention, the section lying parallel to the longitudinal direction of the carriageway.
FIG. 11 is a vertical section corresponding to FIG. 10 through a modified embodiment of the invention.
FIG. 1 is a front elevation of two partly overlapping panel-like structural units 1, 2 in which curved pockets are arranged in rows, radiating alternately from a central plane E, E'. The upwardly curved pockets in the unit towards the bottom of the drawing are denoted by the reference 2a, whilst the downwardly directed pockets are denoted by the reference 2b. Similarly, the upper unit is provided with upwardly directed pockets 2c and downwardly directed pockets 2d. As shown in the Figure, the pockets 2a and 2b and the pockets 2c and 2d lying one behind the other form full-length openings A which even when two units are placed one on top of the other, as shown in the Figure, leave free an opening A' for accommodating a rod-like connecting element. The pockets 2a and 2b and the pockets 2c and 2d each begin flat on the center plane E and E' and, as shown in FIG. 2, form troughs which are concave from the outsides and which are most pronounced at the tops of the pockets.
Arranged between each of the rows of pockets 2a, 2b and 2c, 2d is a full-length corrugation 3, 3a which forms a recess directed to only one side of the unit, in the drawing downwards from the center plane E, E', and whose apex is substantially level with that portion of the pockets 2b and 2d which extends furthest downwards. The walls of the corrugations forming the arms of the V include an angle of about 90° between them. The side walls of the corrugation each merge smoothly with the (in the drawing) upwardly directed pockets 2a, 2c. Since the structural units are identical in shape, the corrugations 3, 3a also interengage exactly in the overlap zone.
The design and relative positions of the pockets are shown in the sectional diagram in FIG. 2. In this case, the section is taken through those portions of the pockets 2a, 2b and 2c, 2d extending fruthest outwards, i.e., through the region in which the concave arching of the pockets is at its most pronounced. Through the arching of the pockets, the pockets which lie one behind the other form openings which lie one behind the other substantially in the center plane of the unit and each of which taper inwards funnel-like from the side edge of the pocket. As shown in FIG. 2, those edges 4 of the pockets which define its end faces include with the planes E, E' an angle 5 of less than 90°. As a result, the pockets are wedge-like in shape as seen from the side. The gaps between two successive pockets are similarly wedge-shaped. This makes it easier to fit the pockets into one another in the overlap zone, whilst the structural units lying one above the other assume relative to one another exactly the position shown in FIG. 2 in which a connecting element can be inserted into the openings A' lying one behind the other. The opening A' also remains intact for the insertion of a thinner connecting element of somewhat smaller internal cross-section in cases where structural units arched around an axis extending transversely of the corrugations are overlapped.
In the panel-like unit 1a shown in FIGS. 3 and 4, which is suitable for example for larger dimensions, the downwardly directed pockets 2f project beyond the apex of the corrugations 3. Those portions projecting furthest outwards, both of the upwardly directed pockets 2e and of the downwardly directed pockets 2f, form flat V-shaped flutes 6 which, compared with FIG. 4, again produce a substantially funnel-like cross-sectional form in the longitudinal openings A surrounded by the pockets.
The panel-like structural units shown in FIGS. 1 to 4 can be installed not only flat but also, as shown in FIGS. 5 and 6, arched, for example for lining tunnels. For this purpose, a structural unit 1 may be arched around an axis parallel to the direction of the rows of pockets, as shown in FIG. 5, or around an axis extending transversely of the rows of pockets as shown in FIG. 6. The corrugations provided between the rows of pockets allow bending in both the aforementioned directions.
FIG. 7 is a section through a tunnel lined with the structural unit according to the invention. For this purpose, units are initially joined together in an arrangement substantially corresponding to the required internal cross-section of the tunnel. The generally irregular gap left between the rock and the unit 1 is filled with pneumatically applied or lean-mixed concrete 7. At the same time, the concrete 7 also fills the spaces behind the pockets 2b, projecting towards the center of the tunnel, between the corrugations 3. In the embodiment shown, that surface of the lining facing the tunnel is coated with a sealing material 8 applied by spraying or any other suitable method. The material 8 penetrates into those spaces which, on the tunnel side, extend up to the backs of the pockets 2a. At the same time, a permanent, reliable bond can be obtained on those surfaces 8a on which the material 8 comes into contact with the concrete 7. The same effect is obtained even when the surface facing the tunnel is sprayed with concrete rather than with the material 8, or otherwise coated. In addition, the special design of the structural unit in any case guarantees an absolutely firm bond between the initially free-flowing coating material and the unit 1.
FIG. 8 is a section through a joint between two overlapping structural units. As already explained with reference to FIG. 1, the pockets 2a, 2b and 2c, 2d lie on one another and fit in one another. In this way, and through engagement of the corrugation 3a of the upper unit with the corrugation 3 of the unit beneath it, the two units are held precisely in their positions relative to one another. The two elements are prevented from being separated from one another by means of a mandrel- or rod-like connecting element 9 which acts as a lock and which at one end is bent round substantially at a right-angle. To enable the connecting element 9 to be inserted into the longitudinal opening, two pockets 2b and 2d have been hollowed out in the embodiment shown in the proximity of the joint between the two structural units. In this way, free zones are formed at the points denoted by the reference 10 from which the connecting element 9 can be introduced.
The same circumstances arise out of FIG. 9 which is a plan view of a joint.
When used as illustrated in FIG. 7, the concave depressions or troughs which, as mentioned earlier on, are arranged at and are at their most pronounced at the tops of the pockets 2a-f, have the advantage that the surface facing the tunnel is uneven and promotes particularly firm adhesion of the sealing material. To ensure that the material 8 adheres firmly, bridges have to be formed between the areas in which the material 8 penetrates into the gaps between the outwardly directed pockets. In the case of pockets which are arched outwards at their apices, the so-called bridge is thinnest at its center. With pockets showing the aforementioned design, a considerably larger proportion of the composition used for sealing rebounds when it is sprayed on so that losses are inevitable and considerable expense involved in applying the composition.
Through the inwardly directed arching of the pockets at their apices, it is also possible to avoid cavities in the concrete which are particularly undesirable in the proximity of the sealing layer because they detrimentally affect the firm bond with this layer.
As already mentioned, the panel-like units described show outstanding strength properties, are easy to store, transport and handle. For this reason, they may also be used in the construction of carriageways, for example runways at airports, roads for tank traffic, and also for soil consolidation. The process applied to this end, which is explained in the following with reference to FIGS. 28 and 29, is extremely easy.
As shown in these Figures, panel-like units 1 with pockets 2a and 2b arranged in rows, are again used as reinforcement for the carriageway to be built. The pockets are directed to opposite sides so that continuous openings are formed. The openings have a free cross-section which tapers inwards from the end faces of the pockets because the pockets are arched in the transverse direction convex-fashion with respect to the main plane of the unit. Arranged between every two rows of pockets is the corrugation 3 which only projects to one aide. At the joints the units are laid with their edges one on top of the other and are connected together by means of rod-like elements which can be pushed through the pockets.
In the construction of a carriageway, the panel-like units 1 are laid on the flattened ground C, as shown in FIG. 10, in such a way that the corrugations 3 face downwards whilst both the corrugations 3 and the rows of pockets extend transversely of the carriageway. By virtue of their design, the panel-like units may be joined together to form surfaces of any required area and outline. The units can be laid out and joined together at considerable speed.
Before use, the panel-like units 1 are dipped in cold asphalt for protection against corrosion and for firm bonding with the surface to be subsequently applied. Plastics-coated units may also be used.
After laying or after a sufficient area has been covered with units, a layer of the required thickness of bitumen macadam 55 is applied to the units 1 lying on the flattened soil C. The entire carriageway is built very quickly and economically.
The embodiment shown in FIG. 11 differs from that shown in FIG. 10 in that grit 52 and stones 53 are applied to the units 1 dipped in cold asphalt. The grit and stones are sprayed with bitumen and rolled. The grit fills the cavities existing through the pockets in the structural units. The surface of the carriageway prepared in this way is gritted and rolled to form a smooth surface 54.
An object of this invention is to provide a structural unit which is readily mated with similar units.
According to the present invention, there is provided a panel-like structural unit particularly for use as permanent formwork and reinforcement in concrete constructions, said unit being formed with corrugations, at least one crest of which is depressed at intervals to form a row of pockets for receiving a connecting element extending longitudinally of the corrugations, whereby overlapping units are connectable, the pockets each decreasing in width, considered longitudinally of the corrugations, with increase in depth of the pocket.
When the edges of two units are overlapped, the pockets (formed both by the depressed portions and the portions of the crest intermediate the depressed portions) of the units mate together.
By virtue of the wedge form given to the pockets, the units mate readily both when the units are flat, and when they are deformed to construct an arch during tunnel construction.
Inter-engagement of the units in the overlap zone is additionally facilitated by the fact that the pockets are arched to reduce their width, for example being of U- or V-form cross-section.
According to another advantageous aspect of the invention, the edges defining the pockets merge substantially along a straight line with the troughs adjacent the crest or crests in which the pockets are formed. This simplifies manufacture of the unit because it is possible to use a tool simpler than that used for conventional units. At the same time, flexural strength is increased, thus enabling the units to be installed with greater unsupported lengths.
A particularly favorable cross-sectional form for the corrugations is obtained where the sides of the troughs include between them an angle of about 90°, because in this way the corrugations lie tightly adjacent one another in the overlap zone and offer particularly high resistance to pressure and tension.
The panel-like structural units of the aforementioned type have excellent strength properties and are easy to store, transport and handle.
It has now been found that the aforementioned structural units may also be used for the construction of carriageways, for example runways at airports, roads for tank traffic, and also for soil consolidation. The process which the invention provides to this end comprises immersing the units in cold asphalt, laying them as sheet-form reinforcement and covering them with the material forming the surface of the carriageway.
One embodiment of the process comprises covering the units with a mixed bitumen coating forming the surface of the carriageway. In another embodiment of the invention, the units are covered with grit and stones which are then sprayed with bitumen and rolled, after which the surface is prepared by gritting and rolling.
The invention is described in detail by way of example only in the following with reference to the accompanying drawings, wherein:
FIG. 1 is a front elevation of two structural units overlapping at the point at which they are joined.
FIG. 2 is a partial section through the units shown in FIG. 1 on the line I--I.
FIG. 3 is a front elevation of a modified embodiment of the structural unit.
FIG. 4 is a section through FIG. 3 on the line III--III.
FIG. 5 is a front elevation corresponding to FIG. 1 of a structural unit installed in an arched position, the arching running parallel to the rows of pockets.
FIG. 6 is a section through the unit shown in FIG. 1 which is arched about an axis extending transversely of the rows of pockets.
FIG. 7 is a partial section through a completed tunnel or gallery lining.
FIG. 8 is a longitudinal section through a joint between two overlapping structural units.
FIG. 9 is a plan view of the joint shown in FIG. 8.
FIG. 10 is a vertical partial section through a carriageway constructed in accordance with the process of the invention, the section lying parallel to the longitudinal direction of the carriageway.
FIG. 11 is a vertical section corresponding to FIG. 10 through a modified embodiment of the invention.
FIG. 1 is a front elevation of two partly overlapping panel-like structural units 1, 2 in which curved pockets are arranged in rows, radiating alternately from a central plane E, E'. The upwardly curved pockets in the unit towards the bottom of the drawing are denoted by the reference 2a, whilst the downwardly directed pockets are denoted by the reference 2b. Similarly, the upper unit is provided with upwardly directed pockets 2c and downwardly directed pockets 2d. As shown in the Figure, the pockets 2a and 2b and the pockets 2c and 2d lying one behind the other form full-length openings A which even when two units are placed one on top of the other, as shown in the Figure, leave free an opening A' for accommodating a rod-like connecting element. The pockets 2a and 2b and the pockets 2c and 2d each begin flat on the center plane E and E' and, as shown in FIG. 2, form troughs which are concave from the outsides and which are most pronounced at the tops of the pockets.
Arranged between each of the rows of pockets 2a, 2b and 2c, 2d is a full-length corrugation 3, 3a which forms a recess directed to only one side of the unit, in the drawing downwards from the center plane E, E', and whose apex is substantially level with that portion of the pockets 2b and 2d which extends furthest downwards. The walls of the corrugations forming the arms of the V include an angle of about 90° between them. The side walls of the corrugation each merge smoothly with the (in the drawing) upwardly directed pockets 2a, 2c. Since the structural units are identical in shape, the corrugations 3, 3a also interengage exactly in the overlap zone.
The design and relative positions of the pockets are shown in the sectional diagram in FIG. 2. In this case, the section is taken through those portions of the pockets 2a, 2b and 2c, 2d extending fruthest outwards, i.e., through the region in which the concave arching of the pockets is at its most pronounced. Through the arching of the pockets, the pockets which lie one behind the other form openings which lie one behind the other substantially in the center plane of the unit and each of which taper inwards funnel-like from the side edge of the pocket. As shown in FIG. 2, those edges 4 of the pockets which define its end faces include with the planes E, E' an angle 5 of less than 90°. As a result, the pockets are wedge-like in shape as seen from the side. The gaps between two successive pockets are similarly wedge-shaped. This makes it easier to fit the pockets into one another in the overlap zone, whilst the structural units lying one above the other assume relative to one another exactly the position shown in FIG. 2 in which a connecting element can be inserted into the openings A' lying one behind the other. The opening A' also remains intact for the insertion of a thinner connecting element of somewhat smaller internal cross-section in cases where structural units arched around an axis extending transversely of the corrugations are overlapped.
In the panel-like unit 1a shown in FIGS. 3 and 4, which is suitable for example for larger dimensions, the downwardly directed pockets 2f project beyond the apex of the corrugations 3. Those portions projecting furthest outwards, both of the upwardly directed pockets 2e and of the downwardly directed pockets 2f, form flat V-shaped flutes 6 which, compared with FIG. 4, again produce a substantially funnel-like cross-sectional form in the longitudinal openings A surrounded by the pockets.
The panel-like structural units shown in FIGS. 1 to 4 can be installed not only flat but also, as shown in FIGS. 5 and 6, arched, for example for lining tunnels. For this purpose, a structural unit 1 may be arched around an axis parallel to the direction of the rows of pockets, as shown in FIG. 5, or around an axis extending transversely of the rows of pockets as shown in FIG. 6. The corrugations provided between the rows of pockets allow bending in both the aforementioned directions.
FIG. 7 is a section through a tunnel lined with the structural unit according to the invention. For this purpose, units are initially joined together in an arrangement substantially corresponding to the required internal cross-section of the tunnel. The generally irregular gap left between the rock and the unit 1 is filled with pneumatically applied or lean-mixed concrete 7. At the same time, the concrete 7 also fills the spaces behind the pockets 2b, projecting towards the center of the tunnel, between the corrugations 3. In the embodiment shown, that surface of the lining facing the tunnel is coated with a sealing material 8 applied by spraying or any other suitable method. The material 8 penetrates into those spaces which, on the tunnel side, extend up to the backs of the pockets 2a. At the same time, a permanent, reliable bond can be obtained on those surfaces 8a on which the material 8 comes into contact with the concrete 7. The same effect is obtained even when the surface facing the tunnel is sprayed with concrete rather than with the material 8, or otherwise coated. In addition, the special design of the structural unit in any case guarantees an absolutely firm bond between the initially free-flowing coating material and the unit 1.
FIG. 8 is a section through a joint between two overlapping structural units. As already explained with reference to FIG. 1, the pockets 2a, 2b and 2c, 2d lie on one another and fit in one another. In this way, and through engagement of the corrugation 3a of the upper unit with the corrugation 3 of the unit beneath it, the two units are held precisely in their positions relative to one another. The two elements are prevented from being separated from one another by means of a mandrel- or rod-like connecting element 9 which acts as a lock and which at one end is bent round substantially at a right-angle. To enable the connecting element 9 to be inserted into the longitudinal opening, two pockets 2b and 2d have been hollowed out in the embodiment shown in the proximity of the joint between the two structural units. In this way, free zones are formed at the points denoted by the reference 10 from which the connecting element 9 can be introduced.
The same circumstances arise out of FIG. 9 which is a plan view of a joint.
When used as illustrated in FIG. 7, the concave depressions or troughs which, as mentioned earlier on, are arranged at and are at their most pronounced at the tops of the pockets 2a-f, have the advantage that the surface facing the tunnel is uneven and promotes particularly firm adhesion of the sealing material. To ensure that the material 8 adheres firmly, bridges have to be formed between the areas in which the material 8 penetrates into the gaps between the outwardly directed pockets. In the case of pockets which are arched outwards at their apices, the so-called bridge is thinnest at its center. With pockets showing the aforementioned design, a considerably larger proportion of the composition used for sealing rebounds when it is sprayed on so that losses are inevitable and considerable expense involved in applying the composition.
Through the inwardly directed arching of the pockets at their apices, it is also possible to avoid cavities in the concrete which are particularly undesirable in the proximity of the sealing layer because they detrimentally affect the firm bond with this layer.
As already mentioned, the panel-like units described show outstanding strength properties, are easy to store, transport and handle. For this reason, they may also be used in the construction of carriageways, for example runways at airports, roads for tank traffic, and also for soil consolidation. The process applied to this end, which is explained in the following with reference to FIGS. 28 and 29, is extremely easy.
As shown in these Figures, panel-like units 1 with pockets 2a and 2b arranged in rows, are again used as reinforcement for the carriageway to be built. The pockets are directed to opposite sides so that continuous openings are formed. The openings have a free cross-section which tapers inwards from the end faces of the pockets because the pockets are arched in the transverse direction convex-fashion with respect to the main plane of the unit. Arranged between every two rows of pockets is the corrugation 3 which only projects to one aide. At the joints the units are laid with their edges one on top of the other and are connected together by means of rod-like elements which can be pushed through the pockets.
In the construction of a carriageway, the panel-like units 1 are laid on the flattened ground C, as shown in FIG. 10, in such a way that the corrugations 3 face downwards whilst both the corrugations 3 and the rows of pockets extend transversely of the carriageway. By virtue of their design, the panel-like units may be joined together to form surfaces of any required area and outline. The units can be laid out and joined together at considerable speed.
Before use, the panel-like units 1 are dipped in cold asphalt for protection against corrosion and for firm bonding with the surface to be subsequently applied. Plastics-coated units may also be used.
After laying or after a sufficient area has been covered with units, a layer of the required thickness of bitumen macadam 55 is applied to the units 1 lying on the flattened soil C. The entire carriageway is built very quickly and economically.
The embodiment shown in FIG. 11 differs from that shown in FIG. 10 in that grit 52 and stones 53 are applied to the units 1 dipped in cold asphalt. The grit and stones are sprayed with bitumen and rolled. The grit fills the cavities existing through the pockets in the structural units. The surface of the carriageway prepared in this way is gritted and rolled to form a smooth surface 54.