EP2288768A1

EP2288768A1 - Precast concrete panel

Info

Publication number: EP2288768A1
Application number: EP09701745A
Authority: EP
Inventors: Milenko Kuzmanovic
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-01-17
Filing date: 2009-01-16
Publication date: 2011-03-02
Also published as: EP2288768A4; AU2009204645B2; AU2009204645A1; WO2009089588A1

Abstract

A precast concrete panel comprising a precast concrete slab having reinforcement members extending through and protruding from the concrete slab, wherein the concrete slab includes at least one flange extending along a side edge of the concrete slab and below the protruding reinforcement members whereby in use the flange abuts against an adjacent concrete panel and the protruding reinforcement members overlap the protruding reinforcement members of the adjacent concrete panel.

Description

PRECAST CONCRETE PANEL

The present invention relates to a precast concrete panel, in particular, a reinforced precast concrete panel that can be joined to adjacent concrete panels and a method of forming a horizontal surface using the concrete panels.

Precast concrete panels are used in a wide range of construction applications, such as bridge construction, and are prefabricated in a controlled environment to be transported as required. In contrast, cast in situ concrete panels, or slabs, must be poured into a formwork structure and the resultant slab may be of inconsistent quality due to variable environmental conditions existing during the pour. Formwork is labour intensive to construct and typically requires a temporary supporting structure to be assembled beneath it. The time taken to construct the formwork, pour the slab, cure the concrete, and subsequently remove the formwork and the supporting structure adds greatly to the expense of the construction application.

Traditional construction methods using precast concrete panels also suffer from numerous drawbacks. The panels are often not joined with any continuity of steel reinforcement and are therefore subject to accelerated cracking and deterioration. The joining of adjacent precast concrete panels also requires time-consuming formwork to be constructed and is subject to inconsistent concrete quality. In addition, any support beams used are required to have special sheer connector arrangements to interconnect with the join.

Positioning of precast panels during construction is also difficult and labour intensive due to the size and weight of the panels. This is especially evident in confined areas where transport is also a concern. To overcome this problem precast concrete panels can be manufactured with voids to reduce weight. However, further reinforcement in the form of an additional layer of concrete, with further reinforcement bars, is typically required to be poured in situ, adding further expense and suffering from the same drawbacks as poured in situ concrete slabs.

The present invention is intended to address the above problems. SUMMARY OF INVENTION

In accordance with one aspect of the present invention there is provided a precast concrete panel comprising a precast concrete slab having reinforcement members extending through and protruding from the concrete slab, wherein the concrete slab includes at least one flange extending along a side edge of the concrete slab and below the protruding reinforcement members whereby in use the flange abuts against an adjacent concrete panel and the protruding reinforcement members overlap the protruding reinforcement members of the adjacent concrete panel.

Preferably the reinforcement members of the adjacent panels are inclined at an angle relative to the side edge of the respective concrete slabs so that the adjacent reinforcement members do not interfere.

Preferably the concrete slab includes two flanges extending along opposed sides.

Preferably the concrete slab is rectangular and the flange extends along a longitudinal side edge of the concrete slab.

Preferably two flanges extend along opposed longitudinal sides of the concrete slab, such that the flanges of adjacent panels abut each other.

Preferably the flange extends level with a bottom face of the concrete slab.

Preferably the reinforcement members protrude beyond an end of the flange.

Preferably the concrete slab includes longitudinally extending voids.

Preferably the reinforcement members are cast in two spaced apart layers extending through and protruding from the concrete slab.

Preferably at least one end of corresponding reinforcement members in different spaced apart layers are connected by a connecting member. Preferably the angle of inclination is less than or equal to 89 degrees and is sufficiently steep to define a gap between adjacent reinforcement members to allow insertion of the adjacent concrete panel.

Preferably the reinforcement members are prestressed rods.

In accordance with another aspect of the present invention there is provided a method of forming horizontal surfaces using precast concrete panels, wherein the concrete panels comprise a precast concrete slab having reinforcement members extending through and protruding from the concrete slab, at least one flange extending along a side edge of the concrete slab and located below the protruding reinforcement members, the method including the steps of: abutting the flange of one concrete panel against an adjacent concrete panel such that the protruding reinforcement members overlap the protruding reinforcement members of the abutted adjacent panel; joining overlapped reinforcement members of abutted adjacent panels; and pouring concrete on top of the abutted flange and adjacent panel and filling the gap therebetween to be level with the adjacent panels, thereby joining adjacent panels to create a horizontal surface.

Preferably the flange abuts against the flange of an adjacent panel.

Preferably the step of joining reinforcement members of abutted adjacent concrete panels further includes joining additional reinforcement members between joined reinforcement members.

In accordance with another aspect of the present invention there is provided a horizontal surface formed using precast concrete panels, the concrete panels comprising a precast concrete slab having reinforcement members extending through and protruding from the concrete slab, at least one flange extending along a side edge of the concrete slab and located below the protruding reinforcement members whereby the reinforcement members are inclined relative to the side edge and wherein the concrete panels are joined together to form a horizontal surface. Preferably the protruding reinforcement members of the concrete panel overlap the reinforcement members of adjacent concrete panels and concrete is poured on top of abutted flanges of adjacent concrete panels filling the gap therebetween to form a horizontal surface.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments, incorporating all aspects of the invention, will now be described by way of example only with reference to the accompanying drawings in which:

Figure 1 is a top view of a precast concrete panel, in accordance with an embodiment of the present invention;

Figure 2 is a cross-sectional view of the precast concrete panel of Figure 1 , taken longitudinally;

Figure 3 is a perspective view of the precast concrete panel of Figure 1 ;

Figure 4 is a cross-sectional view of two adjacent precast concrete panels of Figure 1 being joined; and

Figure 5 is a cross-sectional view of an alternative embodiment of two adjacent precast concrete panels of Figure 1 being joined to a pillar.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

Figure 1 illustrates a precast concrete panel 10 including a concrete slab 12 having reinforcement members extending through and protruding from the concrete slab. Shown in this figure is a rectangular concrete slab with longitudinal 14 and transverse 16 reinforcement members. It is envisaged that other shaped concrete panels may be employed for specific construction applications. The reinforcement members are uniformly distributed and typically steel rods fabricated to carry tensile loads. Other materials, such as steel tendons or rod coatings, are used in particular applications such as highly corrosive environments. The precast concrete panel can also be prestressed for additional strength characteristics using both pre- and post-tensioning methods. Prestressing allows for larger precast concrete panels to be used with wider panel spans between support members. Pre-tensioning has the advantage of eliminating the need for additional post-tensioning equipment and reduces the time and labour required to generate the force needed. However, pre-tensioning may not always be possible or practical and there are certain loading scenarios that require a combination of both pre- and post-tensioning methods to provide the necessary strength characteristics.

The concrete slab 12 includes at least one flange 18 extending along a side edge of the concrete slab and below the reinforcement members. Shown in Figure 1 is the preferred embodiment with the transverse reinforcement members inclined relative to the side edge of the concrete slab. The reinforcement members are inclined so that the opposed ends of the members are offset relative to each other.

The preferred embodiment also shows two opposed flanges extending level with the bottom face of the concrete slab 12 and longitudinally along the entire length of the slab. The opposed flanges are adapted to abut against an adjacent concrete panel, when in use, so that the two panels can be joined together without the need for formwork. Preferably, in use, the flange 18 abuts against the flange of an adjacent concrete panel and the abutting flanges form a gap, or cavity, in which the reinforcement members are located. Concrete is then poured in situ to form a horizontal surface, thus, removing the need for formwork to be constructed around the join. The amount of concrete require to be poured is also reduced when poured on top of the flanges, both saving time and reducing the possibility of inconsistent concrete curing. In a preferred embodiment, the flanges are tapered for additional sheer strength and load distribution characteristics. However, the flanges could be made with uniform thickness. In the scenario where only two panels are required for construction, it is envisaged that one panel may have only one flange on the side where it is adjacent to another panel.

The longitudinal 14 and transverse 16 reinforcement members protrude both beyond the edge of the flange 18 and longitudinally beyond the edge of the concrete slab 12. The protruding reinforcement members can be used to join, or tie, adjacent precast concrete panel reinforcement members in a continuous fashion. The tied reinforcement members enable the loads experienced to be distributed more evenly throughout the joined panels. Thus, preventing cracking at the joins and enabling greater load carrying capacity.

The protruding reinforcement members of adjacent panels overlap each other due to the offset resulting from the angle of inclination of the members relative to the side edge of the slab 12. The angle of inclination is selected to ensure reinforcement members of adjacent concrete panels do not interfere with each other based on the length of protrusion of the reinforcement members and the flange 18 from the slab 12, and the thickness of the members. The angle of inclination of the reinforcement members relative to the side edge of the slab 12 is less than 90 degrees, typically less than or equal to 89 degrees but is sufficiently steep to ensure a gap is defined between the adjacent reinforcement members to allow insertion of the adjacent concrete panel. The available angles will depend on the extent to which the reinforcement members protrude and the thickness of the reinforcement members.

Longitudinal reinforcement members 14 are typically joined to adjacent longitudinal reinforcement members, from an adjacent precast concrete panel, about a support member. The support member is usually a steel girder and includes sheer connectors to provide additional strength and to connect with the adjacent precast concrete panels. Little or no formwork is required when pouring the additional concrete joining adjacent precast concrete panels, about a support member. This is illustrated in the embodiment shown in figure 1 where an adjacent panel 13 with longitudinal 15 and transverse 17 reinforcement members abuts the adjacent concrete slab 12. It can be seen that the two protruding transverse reinforcement members of the adjacent slabs overlap in the horizontal plane. It is also envisaged that the protruding reinforcement members could be arranged to overlap in an alternate plane, such as vertically.

Figure 2 illustrates a cross-sectional view of the precast concrete panel of Figure 1 taken transversely. It can be seen that the plurality of reinforcement members are provided in two spaced apart layers, shown as vertically spaced. Other configurations are also envisaged, depending on the construction application, the size of panel required, and the required strength characteristics. The layered reinforcement members are joined with a connection member 20 and allow for tensile loads to be distributed evenly throughout the height of the precast concrete panel 10. Also shown in this figure is a connection member 22 connecting the layered transversely extending reinforcement members 16. The connection members assist with the joining of adjacent panels and subsequent distribution of loads therethrough.

Figure 3 illustrates a perspective view of the precast concrete panel showing a tapered edge 24 of the flange 18. Again, the reinforcement members are shown to be layered vertically to distribute forces throughout the height of the panel.

Figure 3 also illustrates a plurality of voids 26, uniformly distributed and extending longitudinally throughout the precast concrete slab 12. These voids reduce the weight of the precast concrete panel 10 and are generally uniformly distributed hollow cylinders. Other shapes and configurations of voids could be employed, depending on the strength characteristics required and the amount of weight needed to be saved, according to transportation and/or installation constraints. It is also envisaged that some construction applications will require solid precast concrete panels. The voids 26 can also be used to insert additional post-stressing tendons or other non related services, such as cables. Also illustrated is at least one additional reinforcement member 27 used to reinforce the flange 18.

Figure 4 illustrates two adjacent precast concrete panels 10 joined along their respective longitudinal edges. The two panels each have a precast concrete slab 12 with flanges 18 extending therefrom and abutting against each other to form a gap 28. The gap is adapted to receive protruding transverse reinforcement members and enable a worker to join the reinforcement members together in order to facilitate transmission and distribution of forces amongst adjacent connected panels. Additional reinforcement members 30 can also be joined to protruding reinforcement member 14 and 16 to strengthen the join between adjacent panels. The additional reinforcement members are typically joined or tied perpendicularly to the protruding members.

The gap 28 is enclosed on the underside by the tapered surface 24 of the flanges 18 and as a result no formwork is required to join adjacent panels along the adjacent longitudinal edge. The resultant concrete filled gap and adjacent panels form a horizontal surface.

Figure 5 illustrates an alternative embodiment of the concrete slab 12 whereby the flange 18 is of a greater vertical thickness, has additional reinforcement members 27 and does extend along the bottom face of the slab 12. Shown in this figure are two adjacent slabs 12 joined about a pillar 32. In the example shown, the pillar has vertical reinforcement members 34 protruding through an aperture in the flanges 18 to provide either additional strength to the joined adjacent slabs when tied to the respective transverse reinforcement members or they are used to tie a column 38 supported by the horizontal surface formed by the pouring of concrete on top of the abutted flanges 18.

In the claims which follow and in the preceding description, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or

"comprising" is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

It is to be understood that, if any prior art publication is referred to herein, such reference does not constitute an admission that the publication forms a part of the common general knowledge in the art, in any country.

Claims

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

1. A precast concrete panel comprising a precast concrete slab having reinforcement members extending through and protruding from the concrete slab, wherein the concrete slab includes at least one flange extending along a side edge of the concrete slab and below the protruding reinforcement members whereby in use the flange abuts against an adjacent concrete panel and the protruding reinforcement members overlap the protruding reinforcement members of the adjacent concrete panel.

2. The precast concrete panel as claimed in claim 1 , wherein the reinforcement members of the adjacent panels are inclined at an angle relative to the side edge of the respective concrete slabs so that the adjacent reinforcement members do not interfere.

3. The precast concrete panel as claimed in claim 1 , wherein the concrete slab includes two flanges extending along opposed sides.

4. The precast concrete panel as claimed in claim 1, wherein the concrete slab is rectangular and the flange extends along a longitudinal side edge of the concrete slab.

5. The precast concrete panel as claimed in claim 4, wherein two flanges extend along opposed longitudinal sides of the concrete slab, such that the flanges of adjacent panels abut each other.

6. The precast concrete panel as claimed in any one of the preceding claims, wherein the flange extends level with a bottom face of the concrete slab.

7. The precast concrete panel as claimed in any one of the preceding claims, wherein the reinforcement members protrude beyond an end of the flange.

8. The precast concrete panel as claimed in any one of the preceding claims, wherein the concrete slab includes longitudinally extending voids.

9. The precast concrete panel as claimed in any one of the preceding claims, wherein the reinforcement members are cast in two spaced apart layers extending through and protruding from the concrete slab.

10. The precast concrete panel as claimed in claim 10, wherein at least one end of corresponding reinforcement members in different spaced apart layers are connected by a connecting member.

11. The precast concrete panel as claimed in claim 2, wherein the angle of inclination is less than or equal to 89 degrees and is sufficiently steep to define a gap between adjacent reinforcement members to allow insertion of the adjacent concrete panel.

12. The precast concrete panel as claimed in any one of the preceding claims, wherein the reinforcement members are prestressed rods.

13. A method of forming horizontal surfaces using precast concrete panels, wherein the concrete panels comprise a precast concrete slab having reinforcement members extending through and protruding from the concrete slab, at least one flange extending along a side edge of the concrete slab and located below the protruding reinforcement members, the method including the steps of: abutting the flange of one concrete panel against an adjacent concrete panel such that the protruding reinforcement members overlap the protruding reinforcement members of the abutted adjacent panel; joining overlapped reinforcement members of abutted adjacent panels; and pouring concrete on top of the abutted flange and adjacent panel and filling the gap therebetween to be level with the adjacent panels, thereby joining adjacent panels to create a horizontal surface.

14. The method of forming horizontal surfaces using precast concrete panels as claimed in claim 13, including abutting the flange against the flange of an adjacent panel.

15. The method of forming horizontal surfaces using precast concrete panels as claimed in claim 13, wherein the step of joining reinforcement members of abutted adjacent concrete panels further includes joining additional reinforcement members between joined reinforcement members.

16. A horizontal surface formed using precast concrete panels, the concrete panels comprising a precast concrete slab having reinforcement members extending through and protruding from the concrete slab, at least one flange extending along a side edge of the concrete slab and located below the protruding reinforcement members whereby the reinforcement members are inclined relative to the side edge and wherein the concrete panels are joined together to form a horizontal surface.

17. The horizontal surface as claimed in claim 16, wherein the protruding reinforcement members of the concrete panel overlap the reinforcement members of adjacent concrete panels and concrete is poured on top of abutted flanges of adjacent concrete panels filling the gap therebetween to form a horizontal surface.