WO2000015910A1

WO2000015910A1 - Method of repairing a paved area

Info

Publication number: WO2000015910A1
Application number: PCT/IB1999/001496
Authority: WO
Inventors: Alethea Rosalind Melanie Hall
Original assignee: Alethea Rosalind Melanie Hall
Priority date: 1998-09-15
Filing date: 1999-09-02
Publication date: 2000-03-23
Also published as: AU5382899A

Abstract

A method of repairing a section of a paved area, for example a section of a road (10), includes the steps of breaking up the surface material of the section (16); preparing the section to provide a base; placing a sheet (18) comprising a tube (20) of a flexible material divided by dividing walls (22) of a flexible material into an array of compartments (24) or cells running the length of the tube, the compartments being arranged in rows and columns so that the tube (20) divided by the dividing walls (22) has a honeycomb structure, with a first end of the tube on the base, and a second end of the tube above the first end of the tube; and filling substantially all of the compartments with a filler material which includes a binder, e.g. a cementitious binder, and allowing the binder to set or cure.

Description

METHOD OF REPAIRING A PAVED AREA

BACKGROUND TO THE INVENTION

THIS invention relates to a method of repairing a section of a paved area, such as a road, a runway, a parking lot, a railway line base or the like.

It is well known to form composite or support structures such as roadways, canal or river or bank linings, mine packs, sea walls or the like, from a material having a honeycomb structure, i.e having a plurality of compartments or cells divided by dividing walls, each compartment or cell being filled with a suitable filler material. Examples of such materials for use in the support structures are Hyson-Cells from M & S Technical Consultants and Services (Pty) Limited, Geoweb from Presto Products Co, Tenweb from Tenax Corp, Armater from Crow Company, Terracell from Webtec Inc. Envirogrid from Akzo Nobel Geosynthetics Co and Geocells from Kay tech. However, there is always a need for new methods of utilising this tube material.

SUMMARY OF THE INVENTION

According to a first aspect of the invention there is provided a method of repairing a section of a paved area, comprising the steps of:

(a) breaking up the surface material of the section;

(b) preparing the section to provide a base;

(c) placing a sheet comprising a tube of a flexible material divided by dividing walls of a flexible material into an array of compartments or cells running the length of the tube, the compartments being arranged in rows and columns so that the tube divided by the dividing walls has a honeycomb structure, with a first end of the tube on the base, and a second end of the tube above the first end of the tube; and

(d) filling substantially all of the compartments with a filler material which includes a binder and allowing the binder to set or cure.

By a "paved area" there is meant a road, a runway, a parking lot, a yard, a railway line base or any other area designed to receive or carry traffic.

The product of step (d) is a structure which may either be used as is as the repaired section of the paved area, or may form the so-called "base" of the repaired section of the paved area with a surfacing on top of the "base" , or may form the so-called "sub-base^" of the repaired section of the paved area with a "base" on the "sub-base^" and then a surfacing on the "base" . Thus the method of the invention may include the step, after step (d) of laying a surfacing, e.g asphalt, on the product of step (d).

In step (a), the breaking up of the surface material of the section may be accomplished using a 2, 3, 4 or 5-sided impact roller or the like, or by using a pneumatic drill or the like, which has the effect of breaking up the surface of the paved area, whether the paved area is made of concrete, asphalt, bricks or block pavers or the like.

Preferably, the surface material of the section to be repaired is broken up to a depth of up to 150mm.

In step (b) the section is prepared to provide a base. By "base" there is meant any surface on which the sheet is located. For example, the broken up surface material may be removed to give a base. Alternatively it is possible to make the repair on the top of the broken up surface material so that the broken up surface material provides the base. Further alternatively a suitable base material, e.g sand or stones, may be placed on the section to provide the base.

In step (c), the sheet may be supported in position, prior to the filling of the compartments with the filler material and binder, for example with the use of flexible or rigid strings or stays, attached to the corners of the sheet and then anchored to a solid structure such as the area around the section to be repaired. The use of flexible strings or rigid stays to support a sheet or tube in position is described in more detail in co-pending application PCT/IB 99/00965, which is incorporated herein by reference.

Further alternatively, the outer walls of the sheet may be made sufficiently rigid so that the sheet is self-supporting.

The sheet, i.e the mbe and the dividing walls, may be made from any suitable flexible material. Although the material must possess some degree of flexibility, the degree of flexibility may range from very flexible up to semirigid. The flexible material may be for example a plastics material such as for example a co-extruded or a bi-axially extruded plastics material; a plastics mesh material; a plastics laminate material such as for example a laminate of a plastics material and a metallic material or a textile material; a metallic material; a woven or non- woven textile material; a paper or cardboard material; and the like.

The flexible material is preferably a suitable plastics material.

The sheet, i.e the tube may have any suitable height and any suitable compartment size. For example, the height of the sheet may range from 50mm to 500mm and each compartment may have a wall length of from 5mm up to 2m.

The compartments in the tube may have any suitable cross-section, such as triangular, square, hexagonal or octagonal, but preferably have a square cross-section, i.e each compartment is defined by four walls of substantially equal length.

In a preferred embodiment of the invention, the sheet includes at least two sections, the compartments in one section being of a different size to the compartments in a second section, the size of a compartment being the cross- sectional area thereof at right angles to the axis of the compartment.

Alternatively, in step (c). at least two sheets may be placed side by side on the base, with the compartments of one sheet being of a different size to the compartments of a second sheet.

This permits different portions of the repaired paved area to take different applied loads. For example, when repairing a lane of a road, a sheet may include three sections or strips, the outer two sections or strips having compartments of a smaller size than the compartments of the central section or strip, the outer two section or strips being the portions over which vehicle wheels mostly ride in use.

The use of compartments with different cross-sectional sizes is described in more detail in co-pending application PCT/IB 99/00967 which is incorporated herein by reference.

In step (d), substantially all of the compartments are filled with a filler material which include a binder. The binder may be a cementitious binder such as for example ordinary Portland cement or a high alumina cement or the like. In this case, the cementitious binder may be mixed with an inert filler material such as sand or gravel or the like to form a high strength concrete material.

The binder may also be a bituminous binder or any other binder which provides the filler material/binder mixture with sufficient rigidity and strength in use. Again, the filler material may be sand or gravel or the like.

The filler material may also be rubber chips, with a suitable binder, e.g a polyurethane binder therefor, or the binder and filler material combined may be rubber or urethane blocks or the like, which are either preformed and inserted into the compartments, or formed in situ in the compartments. This is of particular use when repairing a railway line base, so as to provide portions with a degree of resilience to reduce impact on rails and sleepers.

It is also possible to vary the heights of the compartments in a sheet or in adjacent sheets and thus to vary the applied load which may be received by various portions of the repaired paved area.

It may be desirable for adjacent compartments in the tube to interlock one with another, and in this case, the tube and dividing walls may be so designed that a wall or walls of each compartment includes one or more hollow protrusions or one or more hollow recesses or both, for interlocking of adjacent compartments. This is described in more detail in co-pending application PCT/IB 99/00964 which is incorporated herein by reference. In a further embodiment of the invention, in step (d), a first section of compartments may be filled with a first filler material and binder with a first strength, and a second section of compartments may be filled with a second filler material and binder with a second strength, and so on, thus permitting different portions of the repaired paved area to take different applied loads. For example, when repairing a lane of a road, two outer sections or strips of compartments of the sheet may be filled with a first filler material and binder with a first strength, and the compartments of a central section or strip may be filled with a second filler material and binder with a second strength which is less than the strength of the first filler material and binder, again the outer two sections or strips being the portions over which vehicle wheels mostly ride in use.

According to a second aspect of the invention there is provided a sheet comprising a tube of a flexible material divided by dividing walls of a flexible material into an array of compartments or cells running the length of the tube, the compartments being arranged in rows and columns so that the tube divided by the dividing walls has a honeycomb structure, for use in a method of repairing a section of a paved area as described above.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a schematic view of a road being repaired according to the method of the invention; Figure 2 is a schematic view of a second repair of a road; and

Figure 3 is a plan view of a sheet for use in the method of the invention. DESCRIPTION OF EMBODIMENTS

The crux of the invention is a method of repairing a section of a paved area such as a road, a runway, a parking lot or a yard or the like. The paving material may be any type of paving material such as asphalt, concrete, brick or block pavers, or the like.

It is common for sections of roads, runways, parking lots, yards or the like to deteriorate to a point where these sections need repair, while other sections of the road, runway, parking lot, yard or the like are still in good condition. The method of the invention may be used to repair such sections, which may be small or large, in an efficient manner.

The method of the invention will now be described in more detail with reference to Figure 1.

Referring to Figure 1 there is shown a road 10 having two lanes 12, 14. The road 10 includes a section 16 which requires repair.

The first step of the method of the invention is to break up the surface material of the section 16, for example using a three-sided impact roller. The impact roller breaks up the surface material, whether comprised of concrete, asphalt, brick or block pavers or the like, preferably to a depth of about 150mm, and compacts the material below the surface to a depth of 1 to 5m.

Thereafter, the broken up surface material is removed to give a base for the repair. This base is often referred to as the "subgrade" in engineering terms. In the third step of the method of the invention, a sheet 18 consisting of a mbe 20 of a flexible material divided by dividing walls 22 into an array of compartments 24 running the length of the mbe 20, is placed on the base of the section 16 to be repaired. The compartments 24 are arranged in rows and columns so that the tube 20 divided by the dividing walls 22 has a honeycomb structure.

In the fourth step of the method of the invention, the compartments 24 are all substantially filled with a high strength concrete, e.g one which is 40MPa cured.

Once the high strength concrete has set or cured, the road 10 is immediately available for use.

However, if desired, a layer of asphalt may be placed on top of the filled compartments 24 to provide an improved upper surface.

Referring to Figure 2 there is shown a lane 30 of a road which has been repaired according to the method of the invention.

The first step is to break up the surface material of the lane 30, for example using a three-sided impact roller as described above. In this case, the broken up surface material forms a base for the repair. This material may be compacted if necessary.

In the next step of the method of the invention, a sheet 32 consisting of a tube 34 of a flexible material divided by dividing walls 36 into an array of compartments 38 running the length of the tube 34, is placed on the base of the lane 30. The compartments 38 are arranged in rows and columns so that the tube 34 divided by the dividing walls 36 has a honeycomb structure.

In the next step of the method of the invention, the compartments 38B and 38D are all substantially filled with a high strength concrete. The compartments 38A, 38C and 38E are all substantially filled with a concrete which has a lower strength than the high strength concrete filling the compartments 38B, 38D. In this way, two strips 40 are formed, which are capable of receiving a greater applied load, e.g from the wheels of a vehicle travelling along the lane 30, than the strips 42.

Referring to Figure 3 there is shown a sheet 50 consisting of a mbe 52 of a flexible material divided by dividing walls 54 into an array of compartments 56 running the length of the mbe 52.

The compartments 56 are of varying sizes. The compartments 56C and 56E, which again are designed to form the portions of the repaired paved area which receive a higher applied load, i.e the portions on which vehicle wheels travel, are of a smaller cross-sectional size than the compartments 56A, 56D, 56F which in use form portions of the repaired paved area which is not intended to receive the same degree of vehicular traffic as the portions formed from the compartments 56C and 56E.

In addition, there are transitional compartments 56B between the compartments 56A and 56C. 56C and 56D, 56D and 56E, and 56E and 56F. Using the sheet 50, it is not necessary to fill the compartments 56 with differing types of filler and binder. Thus, all the compartments 56 may be filled with the same filler/binder combination, e.g a mixture of a bituminous binder and sand, with the differences in load bearing capacity being provided by the different compartment sizes.

Of course, it is also an option to combine different compartment sizes with different strength materials for an even greater effect.

The advantages of the method of the invention are firstly that small or large sections of a paved area which have deteriorated, may be repaired easily and quickly, and secondly that the repaired surface has a degree of "flexibility" because of the use of the sheet comprising a mbe of a flexible material divided by dividing walls of a flexible material into an array or compartments or cells.

Claims

A method of repairing a section of a paved area comprising the steps of:

(a) breaking up the surface material of the section;

(b) preparing the section to provide a base;

(c) placing a sheet comprising a mbe of a flexible material divided by dividing walls of a flexible material into an array of compartments running the length of the tube, the compartments being arranged in rows and columns so that the mbe divided by the dividing walls has a honeycomb structure with a first end of the mbe on the base, and a second end of the mbe above the first end of the mbe; and

A method according to claim 1 wherein in step (a) the surface material of the section is broken up to a depth of up to 150mm.

A method according to claim 1 or claim 2 wherein in step (b) the broken up surface material is removed to give a base.

A method according to claim 1 or claim 2 wherein in step (b) the broken up surface material provides the base.

A method according to claim 1 or claim 2 wherein in step (b) a suitable base material is placed on the section to provide the base. A method according to any one of claims 1 to 5 wherein in step (c) the sheet is supported in position prior to the filling of the compartments with the filler material and binder.

A method according to any one of claims 1 to 6 wherein the sheet is made from a flexible material selected from the group consisting of a plastics material, a plastics laminate material, a metallic material, a woven or non-woven textile material, or a paper or cardboard material.

A method according to any one of claims 1 to 7 wherein the sheet includes at least two sections, the compartments in one section being of a different cross-sectional size to the compartments in a second section.

A method according to any one of claims 1 to 7 wherein in step (c) at least two sheets are placed side by side on the base, with the compartments of one sheet being of a different cross-sectional size to the compartments of the second sheet.

A method according to any one of claims 1 to 9 wherein the binder is a cementitious binder.

A method according to any one of claims 1 to 9 wherein the binder is a bituminous binder.

A method according to any one of claims 1 to 9 wherein the filler material comprises rubber chips with a suitable binder therefor. A method according to any one of claims 1 to 12 wherein in step (d) a first section of compartments is filled with a first filler material and binder with a first strength, and a second section of compartments is filled with a second filler material and binder with a second strength, and so on.

A method according to any one of claims 1 to 13 wherein after step (d) a surfacing is laid on the product of step (d).

A sheet comprising a mbe of a flexible material divided by dividing walls of a flexible material into an array of compartments running the length of the mbe, the compartments being arranged in rows and columns so that the mbe divided by the dividing walls has a honeycomb structure, for use in a method of repairing a section of a paved area according to any one of claims 1 to 14.