US20060034654A1

US20060034654A1 - Temporary driveway

Info

Publication number: US20060034654A1
Application number: US10/917,969
Authority: US
Inventors: Mark Sanders
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-08-13
Filing date: 2004-08-13
Publication date: 2006-02-16

Abstract

A temporary driveway for new home construction includes one or more removable pre-cast planks. The pre-cast planks are constructed of reinforced pre-cast concrete and are sized to accommodate the passage of vehicles over their surface. The reinforcement is in the form of a row of pre-stressed cables adjacent the top surface and the bottom surface of the plank. Four lift inserts are recessed into the top surface of the plank near each of the corners of the plank to balance the load during lifting. The pre-cast planks are lifted with a standard lifting rig such as a boom crane attached to the lift inserts. The pre-cast planks are transported to a construction site, lifted from the transport vehicle by a standard lifting rig, and placed in a desired location at a new home construction site. Several pre-cast planks are placed end-to-end to form the temporary driveway. When the temporary driveway is no longer needed, the pre-cast planks are lifted and transported away from the construction site.

Description

BACKGROUND OF THE INVENTION

The present invention relates generally to the construction of driveways and particularly to the construction of temporary driveways used in new home construction.
The driveway provides access to the construction site and is typically one of the first things constructed when a new home is being built. One option that may be used for a driveway in new home construction is to simply put the permanent driveway in place. However, installation of a finished surface such as concrete or blacktop prior to the construction is problematic because construction vehicles such as concrete trucks, hauling trucks, and other equipment can easily damage the finished surface of the driveway. For instance, a finished concrete driveway is typically only four inches thick. While this thickness is adequate for normal traffic associated with residential property, it is likely not sufficient for construction traffic.
Therefore, one form of temporary driveway used during building construction is a gravel driveway. Large gravel is typically poured from a dump truck and spread in a desired location. However, there are problems commonly associated with this form of driveway. One problem is that the placement of the gravel can be time consuming. The gravel must first be poured in place and then spread to form a relatively flat surface.
Another significant problem is water drainage. The surface of a finished driveway is contoured to control water drainage. However, a gravel drive cannot be similarly prepared. If water drainage is not controlled, water that pools on the surface can wash away gravel. Moreover, improper water runoff often creates serious problems including flooding in areas that are not capable of handling the excess water.
Another common problem of gravel driveways is keeping the gravel in the temporary driveway during heavy construction traffic. Traffic over the gravel can cause the gravel to disperse and spill past the boundaries of the driveway into the yard. Keeping the gravel in its intended location can be a time consuming and labor intensive job. Gravel that has been displaced into the yard can pose a hazard where gravel is buried when the lawn is prepared.
The removal of the gravel after it is no longer needed poses another problem. Most homeowners prefer to replace the gravel driveway with a finished concrete or blacktop driveway after construction. In this case, some or all of the gravel will have to be removed and the driveway re-graded to prepare for the new concrete or asphalt driveway which adds time, labor, and expense to the construction process.
Similar problems arise in other construction projects where a temporary driving or parking surface is needed. For instance, some larger construction projects, such as a housing subdivision, include a central office with adjacent parking. Other construction projects require a staging area for temporary retention of building materials. In most cases, a temporary gravel surface is prepared, which poses the problems mentioned above.
What is needed is a temporary driveway that eliminates the problems associated with driveways that are traditionally used during new home construction.

SUMMARY OF THE INVENTION

In order to address these needs, the present invention contemplates a temporary driveway for use during new home construction. The temporary driveway is placed on a new home lot at the start of construction and is removed when construction is completed. According to one embodiment of the invention, the temporary driveway comprises one or more pre-cast planks dimensioned to accommodate the passage of vehicles.
According to one form of the invention, the temporary driveway is in the form of a pre-cast reinforced concrete panel or plank. The concrete plank is formed in a casting bed which consists of a pair of end abutments with a fixed flat surface between them on which the concrete is poured, and with fixed side forms that extend the full length of the flat surface to contain and shape the concrete. In one embodiment, a continuous length of concrete is cast and then cut to a desired length. For a typical driveway plank, the pre-cast concrete is cut to a twelve foot length.
A concrete reinforcement is then placed in desired locations and the concrete poured. In some embodiments of the present invention, rebar can be used to reinforce the concrete. Preferably, the concrete reinforcement takes the form of pre-stressed cables. When using pre-stressed cables, the end abutments are anchorages used to anchor the ends of the cables. The cables are preferably ½″ diameter steel cables stretched between the two anchorages to a predetermined tension. In a specific embodiment, the cables are stressed to 31,000 psi. In a most preferred embodiment, two rows of pre-stressed cables are provided, one row adjacent the top and bottom surfaces to prevent warping of the slab. With the cables under stress, the concrete is poured, encasing the cables. After the concrete has cured, the cables are released from the anchorages. As each length of plank is cut, the cable tension pulls the plank into compression, which increases the strength and durability of the plank.
In a further feature of the invention, the temporary driveway is provided with a lifting system. The lifting system facilitates transport and placement of the temporary driveway at desired locations, without obstructing the top surface of the temporary driveway. Preferably, the lifting system includes at least two lifting points at a front portion of the pre-cast plank and at least two lifting points at a rear portion of the body. In this way, the temporary driveway can remain level and balanced as it is lifted, transported, or lowered.
According to one form of the invention, the lifting system takes the form of lift inserts recessed into the top surface of the pre-cast plank. The lift inserts can be embedded in the casting material or attached to the reinforcement. Preferably, the lift inserts have an opening at one end allowing the pre-stressed cables or rebar to be fed through. The lift inserts are placed at desired lifting points and positioned so that the lifting portions of the inserts are adjacent to or just below the top surface of the pre-cast plank. A cap covers the lifting portion of the insert. Once the concrete has been poured and set, the cap is removed exposing the lifting portion of the insert. Preferably, the lift inserts are dogbone inserts. Alternatively, other forms of lift inserts may be used such as anchor, coil, or plug type lifting inserts. In other embodiments, the lifting system can be lifting rings embedded in the sides of the pre-cast plank or threaded into embedded thread cores.
The present invention further contemplates a method for constructing a temporary driveway for a new home construction site. The method comprising the steps of:

- a. providing at least one pre-cast plank
- b. preparing a desired location to temporarily support the planks;
- b. transporting the planks to the desired location;
- c. lowering the planks into position to form the temporary driveway; and
- d. removing the temporary driveway from the location once work is complete at the location.

It can be appreciated that the present invention contemplates a temporary driveway that can be used for new home construction sites. The temporary driveway is reinforced to endure the heavy traffic associated with new home construction. In addition, the temporary driveway includes features that facilitate transportation to and from a desired location. These features of durability and portability allow the temporary driveway to be used, stored, and reused as needed. This greatly simplifies and hastens the process of constructing a driveway. When a new home is being constructed, the temporary driveway can be transported and placed at the construction site at the start of construction, and removed when construction is completed.
It is, therefore, an object of the present invention to provide a novel, efficient, and economical apparatus and method of forming a temporary driveway. It is a further object of the present invention to provide a temporary driveway that alleviates problems associated with the driveways that are traditionally used in new home construction. For instance, the temporary driveway eliminates the hassles of a gravel driveway including: placing the gravel, keeping the gravel in its intended location, and removing the gravel after it is no longer needed.
Another object of the present invention is to provide a temporary driveway that is sturdy enough to handle heavy equipment and high traffic volume associated with new home construction. Yet another object of the present invention is to provide a temporary driveway that can be pre-cast off-site before construction begins with the capability of being lifted and transported to and from a construction site when needed.
These and other objects and benefits of the invention will be readily discerned from the following written description, taken together with the accompanying figures.

DESCRIPTION OF THE FIGURES

FIG. 1 is a plan view of a temporary driveway in place at a new home construction site.
FIG. 2 is a side elevation view of the temporary driveway shown in FIG. 1.
FIG. 3 is a top elevation view of a pre-cast plank for the temporary driveway shown in FIG. 1.
FIG. 4 is an end elevation view of the pre-cast plank as shown in FIG. 1.
FIG. 5 is a cross sectional view of the pre-cast plank shown in FIG. 4 taken along section line 5-5 as viewed in the direction of the arrows.
FIG. 6 is a cross sectional view of the pre-cast plank shown in FIG. 3 taken along section line 6-6 as viewed in the direction of the arrows.
FIG. 7 is a perspective view of a casting bed used to form pre-cast planks for the temporary driveway shown in FIG. 1.
FIG. 8 is a perspective view of a pre-cast plank for a temporary driveway being lifted by a lifting rig.

DESCRIPTION OF THE PREFERRED EMBODIMENT

For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and described in the following written specification. It is understood that no limitation to the scope of the invention is thereby intended. It is further understood that the present invention includes any alterations and modifications to the illustrated embodiments and includes further applications of the principles of the invention as would normally occur to one skilled in the art to which this invention pertains.
Referring to FIGS. 1 and 2, the present invention contemplates a temporary driveway 10 for placement on a new home construction site 11. According to the preferred embodiment, the temporary driveway 10 comprises one or more pre-cast planks 12 positioned to provide access to the new home site 11. The pre-cast planks 12 are formed of a castable or extrudable material having high surface hardness and high compressive strength. The material also most preferably has a surface roughness conducive to use as a vehicle driving surface. Concrete is the most preferred material because it meets all of these material requirements and is generally economical to produce. However, other suitable castable or extrudable materials may be used that have the above properties making the material suitable of use as a temporary driving surface. For instance, a high strength polymer such as polypropylene or resin may be used.
Referring now to FIGS. 3 and 4, the preferred embodiment of a pre-cast plank 12 for the temporary driveway 10 is shown. The pre-cast plank 12 includes a top surface 13, a bottom surface 14, a first and second ends 15 and 16, and first and second sides 17 and 18. The pre-cast plank 12 should have at least one dimension sized to accommodate the passage of a vehicle on the top surface 13. In the preferred embodiment, the pre-cast plank 12 has a dimension W between the sides 17, 18 which is approximately ten feet, a dimension L between ends 15, 16 which is approximately twelve feet, and a thickness dimension T which is approximately nine inches. These dimensions offer advantages for use as a temporary driveway. For instance, the pre-cast plank 12 can still cover a substantial area but is not too large to be transported by a standard lifting rig. The ten foot width accommodates most construction vehicles. The twelve foot length emulates a standard poured driveway construction and is sized so that a wide range of useful driveway lengths can be achieved. Finally, the thickness makes the pre-cast plank 12 durable for withstanding a high volume of heavy equipment traffic that is likely to be passing over the top surface 13 during construction. The pre-cast plank 12 is thicker than a standard poured drive because the temporary driveway is intended to endure heavy vehicle loads. Moreover, since the pre-cast planks of the present invention can be re-used at many job sites, the planks must withstand many more vehicle miles traveled than a standard residential drive.
As mentioned above, the pre-cast plank 12 is preferably formed of concrete. In order to increase the tensile strength of the pre-cast plank 12, the concrete is reinforced. Referring to FIG. 5, the reinforcements, in the preferred embodiment, are pre-stressed cables 19. As shown in FIG. 4, the pre-stressed cables 19 are arranged in an upper row 20 and a lower row 21 of cables. The upper and lower cable rows 20, 21 span the entire length L of the pre-cast plank 12 and are most preferably evenly spaced across the width W. The upper row 21 of cables are embedded in the pre-cast plank 12 near the top surface 13 while the lower row 21 of cables are embedded in the pre-cast plank near the bottom surface 14. Preferably the cable rows are embedded 1-2 inches beneath each surface 13, 14. In an exemplary placement of the pre-stressed cables, nine cables 19 are used in both rows, all spaced at about one foot intervals. Two rows are preferred so that the plank is uniformly loaded or pre-stressed across its entire cross-section. This uniform loading prevents warping of the pre-cast planks. The number and diameter of the cables 19 can be varied depending on the size of the pre-cast plank and the casting material used.
It can be appreciated that the reinforcements can be rebar or other suitable materials or methods that are used to reinforce casting material. However, pre-stressed cables are preferred because they tend to place the concrete plank in compression along its length. The pre-stressing improves the compression strength and creep deformation properties of the pre-cast planks.
As shown in FIG. 3, the top surface 13 of the pre-cast plank 12 includes four lifting points 30. In the preferred embodiment, a lifting point 30 is positioned near each corner of the top surface 13 so the pre-cast plank 12 can remain level and balanced as it is lifted, transported, and lowered. For stability during transport, the lifting points are arranged about 2-2½ feet inboard from each side of the plant.
A cross section of a lifting point 30 is shown in FIG. 6. In the preferred embodiment, the lifting point 30 includes a dogbone insert 22 recessed into the top surface 13 of the pre-cast plank 12. The lifting portion 23 of the dogbone insert 22 is exposed in the recess 25 so that a lifting apparatus, such as a grappling hook, can be attached to the lifting portion to lift the pre-cast plank 12. Before the casting material is poured, a cap 29 (FIG. 7) can be used to cover the lifting portion 23 of the lift insert 22. Once the concrete has been poured and set, the cap is removed exposing the lifting portion 23 of the insert 22 within the recess 25.
The dogbone insert 22 has an attachment portion 24 embedded within the casting material. In one approach, the attachment portion 24 defines an opening 24 a sized to snugly receive a cable 19 from the upper row 20 of cables before the plank 12 is formed. This method of attaching the lift insert 22 ensures that the lift point 30 is capable of withstanding the weight of the pre-cast plank as it is lifted. As an alternative, the attachment portion 24 can be configured in two pieces to allow attachment to the cable after it has been pre-stressed. In other embodiments, the lift insert 22 can be embedded without attachment to the reinforcements. It can also be appreciated that other forms of lift inserts and methods of lifting the planks as are known in the art may be used. By way of non-limiting examples, anchor, coil, and plug type inserts recessed into the top surface 13 or lifting rings embedded into the sides of the pre-cast plank 12 may be used.
Referring now to FIG. 7, the pre-cast plank 12 can be formed according to conventional concrete forming techniques, such as extrusion or slip-forming. In one approach, the pre-cast plank 12 is formed in a casting bed 25 which consists of a pair of abutments 26 with a fixed flat surface 27 between them on which the concrete is poured, and with fixed side forms 28 that extend the full length of the flat surface 27 to contain and shape the concrete. In the preferred embodiment, the casting bed 25 is approximately 400 feet long with a concrete extruder 31 disposed in the bed 25 to dispense the concrete.
The pre-stressed cables 19 are stretched between the two abutments 26 and are anchored to the abutments to maintain their tension. Preferably, the cables 19 are stressed to approximately 31,000 psi. It can be appreciated that as the cables 19 are stretched across the casting bed 25, the cables 19 may be threaded through the opening 24 a in the lift inserts 22 at desired locations for placement of the lifting points 30 for each pre-cast plank 12. As mentioned above, a cap 29 covers the lifting portion of the insert 22. The top of the cap (not shown) should be positioned so as to be exposed after the concrete is poured. The cap can then be removed after the concrete has set to provide access to the lift insert 22 within the recess 25.
As mentioned above, the extruder 31 is disposed in the casting bed. The extruder 31 is operable to traverse the length of the bed between the abutments 26. In a preferred embodiment, the extruder 31 is equipped with a guide plate to guide the movement of the extruder 31 down the length of the bed 25. The guide plate has holes through which the pre-stressed cables 19 are fed before the cables 19 are anchored to the abutments 26. As is conventional in the art, the extruder 31 is equipped with a trough that extends from an opening at the top of the extruder to an area adjacent the casting bed. The extruder moves along the length of the casting bed along the pre-stressed cables as concrete is poured into the trough. The concrete flows from the back of the extruder into the casting bed in an even distribution across the width of the bed.
Before the concrete has cured, the top surface 13 is preferably provided with a surface treatment that can enhance the frictional resistance of the surface. In the preferred embodiment, the top surface 13 is given a brush-textured finish or broom finish. Alternatively, other types of finishes and surface treatments may be used as are known in the art. The broom finish gives the top surface 13 a rough texture that provides traction. Optionally, drainage grooves or other gross features can be formed in the surface. After the concrete has cured, the cables 19 are released from the abutments 26 and the cast length of concrete is cut into planks of desired length. The pre-cast planks 12 are then removed from the bed 25.
Prior to installation of the temporary driveway 10, the driveway location is prepared in accordance with known construction methods. For instance, the location is cleared and then graded and compacted to provide a relatively smooth flat surface on which the planks are laid.
As can be seen from FIG. 8, for installation of the temporary driveway 10 a pre-cast plank 12 is lifted by a lifting rig 50 engaged at the lifting points 30. The lifting rig 50 can be of conventional construction to support and transport the pre-cast plank 12, such as a boom crane or the like. The positioning of the lifting points 30 allows the pre-cast plank 12 to be carried in a balanced position so that the pre-cast plank 12 can be easily and accurately lowered into the positions shown in FIGS. 1 and 2. Depending on the desired size of the driveway, one or more pre-cast planks 12 may be installed end-to-end to complete the temporary driveway 10. The position of the lifting points allow each plank to be carried in a substantially level orientation, which facilitated positioning a subsequent plank next to a pre-positioned plank. The lifting rig can be easily manipulated to nestle the planks in direct end-to-end contact. Since the drive way is temporary, there is no need to fill the joint between the planks.
Once construction of the house or building is completed or the temporary driveway is no longer needed, each pre-cast plank 12 can then be lifted by engaging the lifting points 30 again as shown in FIG. 8. The planks are loaded onto a hauling truck and transported to another construction site, a storage facility, or any other desired location.
It is also contemplated that a pre-cast plank already in position in a temporary driveway can be removed and replaced if the plank becomes damaged. The placement of the lifting points for access at the top surface of the plank allows any plank to be removed without disturbing adjacent planks in the temporary driveway.
As described above, the location for the temporary driveway is preferably graded in preparation for receiving the planks. The location can be graded as if in preparation for a standard poured drive. However, one benefit of the pre-cast planks is that the location need not be ideally graded and prepared. In other words, the planks can be positioned over a rough graded location that may not be entirely uniform. The weight of the planks will tend to smooth out some of the roughness and unevenness of the rough grade. However, the resulting driving surface does not need to be residential grade since it will only be subject to construction traffic while the house is being built.
While the invention has been illustrated and described in detail in the drawings and foregoing description, the same should be considered as illustrative and not restrictive in character. It is understood that only the preferred embodiments have been presented and that all changes, modifications and further applications that come within the spirit of the invention are desired to be protected.
Thus, while the present invention contemplates a temporary driveway, other uses requiring a temporary surface capable of supporting heavy loads and/or vehicle traffic are contemplated. By way of non-limiting examples, the present invention can be used for a temporary parking lot, a staging area, and load storage. In addition, the size of the pre-cast planks can be altered for particular uses. However, the overall dimensions of the planks are preferably dictated by the impact on the transportability of the planks. For instance, the present invention contemplates that the planks can be easily transported using standard hauling vehicles, such as a flat bed trailer. Moreover, it is contemplated that the weight and inertia of the planks are amenable to be lifted by a conventional crane used at a residential construction site.

Claims

1. A method for constructing a temporary driveway comprising the steps of:

preparing a location at a job site as a temporary driveway location;

transporting at least one pre-cast plank to the location;

successively positioning each plank adjacent each other at the location to form a temporary driveway; and

subsequently removing the pre-cast plank from the location.

2. The method for constructing a temporary driveway of claim 1, wherein the step of transporting includes loading the at least one pre-cast plank onto a hauling vehicle and unloading the at least one plank form the vehicle at the job site.

3. The method for constructing a temporary driveway of claim 1, wherein the step of successively positioning each plank includes lifting each plank with the plank substantially horizontal and lowering the horizontally positioned plank onto the location.

4. The method for constructing a temporary driveway of claim 1, wherein the pre-cast plank is formed of concrete.

5. The method for constructing a temporary driveway of claim 1, wherein the step of preparing a location includes at least rough grading the location to form a driveway.

6. The method for constructing a temporary driveway in which each pre-cast plank has a plurality of lifting elements embedded within the plank and the step of successively positioning includes engaging the lifting elements.

7. A temporary driveway comprising:

a plurality of pre-cast planks positioned end-to-end to form a driveway surface for a motor vehicle; and

a plurality of lifting elements embedded within a top surface of each of said plank, said lifting elements configured to be removably engaged by a lifting apparatus to lift, transport and lower each pre-cast plank onto the location for the temporary driveway.

8. The temporary driveway of claim 7, wherein each of said plurality of pre-cast planks has a length of about 10 feet and a width of about 12 feet.

9. The temporary driveway of claim 7, wherein each of said plurality of pre-cast planks has a thickness of at least about 8 inches.

10. The temporary driveway of claim 7 wherein each of said plurality of pre-cast planks is formed of concrete.

11. The temporary driveway of claim 10, wherein each of said plurality of planks is cut from a single extruded concrete plank.

12. The temporary driveway of claim 7 wherein each of said plurality of pre-cast planks is reinforced with an array of pre-stressed cables spanning a length of said plank.

13. The temporary driveway of claim 12 wherein said array of pre-stressed cables includes an upper row of a plurality of cables and a lower row of a like plurality of cables, wherein said upper row is embedded within said plank adjacent to the top surface thereof and said lower row is embedded within said plank adjacent to the bottom surface thereof.

14. The temporary driveway of claim 13, wherein cables of said upper and lower rows are spaced at approximately one foot intervals.

15. The temporary driveway of claim 12, wherein each of said pre-stressed cables is stressed to 31000 psi.

16. The temporary driveway of claim 7, wherein said plurality of lifting elements includes four lift inserts recessed within said top surface and position ed on said top surface so that said plank can be lifted and carried by said lift inserts in a substantially horizontal orientation.

17. The temporary driveway of claim 16, wherein said plurality of lifting elements includes a first pair of spaced apart lift inserts recessed into said top surface adjacent a first end and a second pair of spaced apart lift inserts recessed into said top surface adjacent an opposite second end.

18. The temporary driveway of claim 16, wherein:

each of said plurality of pre-cast planks is reinforced with an array of pre-stressed cables spanning a length of each plank; and

each said four lift inserts are attached to a corresponding one of said pre-stressed cables.

19. The temporary driveway of claim 16 wherein said four lift inserts are dogbone lift inserts.

20. The temporary driveway of claim 7 wherein the pre-cast plank is formed of a polymeric or resin material.