AU2016225892B2

AU2016225892B2 - Modular bridge, modular component and method for constructing modular bridge

Info

Publication number: AU2016225892B2
Application number: AU2016225892A
Authority: AU
Inventors: John Alfred Hilton
Original assignee: Aurecon Group Brand Pty Ltd
Current assignee: Aurecon Group Brand Pty Ltd
Priority date: 2015-09-28
Filing date: 2016-09-09
Publication date: 2022-05-19
Anticipated expiration: 2036-09-09
Also published as: NZ724112A; AU2016225892A1

Abstract

A system for construction of a bridge, comprising one or more modular components, each component comprising a precast concrete body that is joinable to an adjacent 5 structure via a joining zone therebetween, the precast concrete body having a first reinforcing element extending therefrom and adapted to cooperate with a second reinforcing element from the adjacent structure in the joining zone, the modular component being joinable to the adjacent structure by insitu casting of a curable material in the joining zone to produce a cured, reinforced joint (stitch) between the 10 modular component and the adjacent structure. 81721521 (GHMatters)P100843.AU. MICHELLEH 8/09/16 2/4 ----- - .-" .* X'4-X N.XC :-X.$' X-X-X .:-X. 44.-X 4' I. -- -- -------- ... ..... .. .. .. .. . . .. . . . .. .. .. .. . .. ... .... .<A ........ \. ...... ... .. . . ......... . F......... L..........

Description

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F. . . . . L.......... MODULAR BRIDGE, MODULAR COMPONENT AND METHOD FOR CONSTRUCTING MODULAR BRIDGE

TECHNICAL FIELD A modular bridge and method for constructing same are disclosed. Also disclosed is a modular component for use in constructing the modular bridge.

BACKGROUNDART Over the years a number of bridge types and construction methods have been developed. The selection of a particular bridge type and construction method depends on a range of factors, including the nature of the crossing and other specific site factors, available and cost effective construction materials, the anticipated span length and overall bridge length and the proposed vertical and horizontal alignment of the bridge. In Australia there are a number of established bridge forms which have been developed for small to medium sized bridges, e.g. a span range of 6 to 24 metres. Bridges of this span and length are very common, with a function to allow vehicular and pedestrian crossing of watercourses, floodplains, creeks, roads and railway lines etc. Applications range from small low speed vehicle single lane farm crossings to full high speed vehicle motorway construction. As different state road authorities often have differing standards and requirements some of these bridge forms tend to be state specific, but a number can be applied across the country.

Due to their low construction and maintenance costs, most small to medium span bridges are constructed from concrete. Concrete in bridges can be utilized as either precast or cast insitu. Precast concrete members are constructed off site (or at least away from their final location) and transported to the bridge site for erection. Erection of precast members is usually by crane. Cast insitu members are constructed in their final location using temporary or permanent formwork.

In the precast method, the concrete bridge deck (which comprises the structural elements providing the running surface for, and supporting road and pedestrian traffic) is fully precast whereas in the cast in situ method, the bridge deck is either fully cast

18673373_1 (GHMatters) P100843.AU.1 28/04/22 insitu or at least comprises a cast insitu running surface for traffic and pedestrians and is composite with supporting precast members. For bridge spans in the range 6-24m the bridge substructure typically comprises transverse concrete (either precast or cast insitu) headstocks and abutment beams supported on precast concrete driven piles, or cast insitu bored piles. Whether the bridge deck is of precast or cast insitu construction, transverse deck joints are usually provided at the abutments, which are the substructure elements at the ends of a bridge whereon the bridge's superstructure rests or contacts to provide vertical and lateral support for the bridge. The abutments are usually designed to be rigid and to be self-supporting under the lateral effects from earth pressure and surcharge without the need for propping from the deck.

Bridges in the span range 6-24m with a composite cast insitu concrete deck usually have the deck overlying, and supported by, longitudinal precast concrete girders. The deck is then designed to act compositely with the girders, and ties the girders together. The girders are typically rectangular in cross section and placed on discrete elastomeric bearings or elastomeric strip bearings. The girders are typically connected to the substructure using galvanised steel dowels.

In contrast, bridges with a fully precast deck comprise precast concrete girders connected together with suitable means such as galvanised bolts, or transverse post tensioning. The girders are typically inverted U or double T cross section and are typically connected to the substructure using galvanized steel holding down bolts. The double T girders need to be placed on an elastomeric bearing strip (or discrete elastomeric bearings) using jacks, to ensure uniform bearing.

Bridges with a composite cast insitu concrete deck exhibit a number of disadvantages. The construction cost is significantly higher than for the precast method due to the need for a full cast insitu deck with two layers of reinforcement. Also, there is a significantly longer construction time (and where replacing an existing bridge on the same alignment, longer road closure) than the precast method.

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Bridges that are constructed using the precast method also suffer from disadvantages. Double T girders need to be erected on jacks and lowered into position to ensure even bearing on the four support points. If the bridge is overtopped, the girders of some of these bridge systems are vulnerable to detaching, due to the sometimes tenuous method of attachment to the substructure.

The inherent nature of the fully precast method is that the bridge deck readily allows passage of water into the substructure elements below. This often produces staining of the piers and abutments, and allows ready access for water to deteriorate bearings, and exposed steelwork.

Another disadvantage of the fully precast method is that often poor rideability can be experienced by road users due to the difficulty in matching adjacent precast member levels, and the unsuitability of this bridge type for asphalt overlays. For this reason, this bridge type is not suitable for high speed roads or for motorway construction. Moreover, the exposed steelwork in the fully precast method needs ongoing inspection and maintenance. For these and other reasons, some bridge systems of this type do not comply with the relevant government requirements.

Bridges constructed using both cast insitu and precast methods share the additional disadvantages of eventual deterioration and need for replacement of the elastomeric bearings and the deck joints at the abutments and piers.

There is accordingly a need for a system and method for constructing bridges that overcome, or at least alleviate, one or more disadvantages of the prior art.

The above references to the background art do not constitute an admission that the art forms a part of the common general knowledge of a person of ordinary skill in the art. The above references are also not intended to limit the application of the apparatus and method as disclosed herein.

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SUMMARY OF THE DISCLOSURE In a first aspect there is disclosed a system for construction of a bridge, comprising one or more modular components, each component comprising a precast concrete body that is joinable to an adjacent structure via a joining zone therebetween, the precast concrete body having a first reinforcing element adapted to extend into the joining zone and the adjacent structure having a second reinforcing element adapted to extend into the joining zone, the first and second reinforcing elements being offset and spaced with respect to each other to allow them to overlap and/or interleave and jointly provide substantially even reinforcement in the joining zone, the modular component being joinable to the adjacent structure by insitu casting of a curable material in the joining zone to cover the first and second reinforcing elements and, after curing of the curable material, to thereby produce a cured, reinforced joint (stitch) between the modular component and the adjacent structure.

In a second aspect there is disclosed a modular component for use in the above system for construction of a bridge, the modular component comprising a precast concrete body that is joinable to an adjacent structure via a joining zone there between, the precast concrete body having a first reinforcing element adapted to extend into the joining zone and the adjacent structure having a second reinforcing element adapted to extend into the joining zone, wherein, in use, thefirst and second reinforcing elements are offset and spaced with respect to each other to allow them to overlap and/or interleave and jointly provide substantially even reinforcement in the joining zone, the modular component being joinable to the adjacent structure by insitu casting of a curable material in the joining zone to cover thefirst and second reinforcing elements and, after curing of the curable material, to thereby produce a cured, reinforced joint (stitch) between the modular component and the adjacent structure.

In an embodiment, the modular component is a girder component.

In an embodiment, the modular component is a combined deck and girder component. The upper surface of such a modular component comprises the traffic

18673373_1 (GHMatters) P100843.AU.1 28/04/22 carrying surface and does not require an asphalt overlay except for high speed applications.

In an embodiment, the adjacent structure is another modular component. The respective concrete bodies of the modular components may have substantially the same configuration. The first and second reinforcing elements on adjacent sides of respective modular components may be offset with respect to each other to allow them to cooperate with each other. The cooperation may comprise overlapping or interleaving of the first and second reinforcing elements. For example, where the reinforcing comprises steel reinforcing bars that extend laterally from the modular component, they may be laterally offset with respect to each other to avoid mutual interference and to jointly provide even reinforcement in the joining zone. The first and second reinforcing elements may comprise starter bars that are supplemented by additional reinforcement added to the joining zone. All reinforcing elements may be applied in the precast yard, thus obviating the need to place individual reinforcing elements on site.

In an embodiment, the adjacent structure is substructure for the bridge. The substructure may be for example an abutment or a headstock. The first and second reinforcing elements on adjacent sides of a modular component and the adjacent structure may be offset with respect to each other to allow them to cooperate with each other. The cooperation may comprise interleaving of the first and second reinforcing elements. For example, where the first reinforcing element comprises steel reinforcing bars that extend from the modular component, they may be laterally offset with respect to the second reinforcing element extending from the adjacent structure to avoid mutual interference and to jointly provide even reinforcement in the joining zone. Thefirstand second reinforcing elements may comprise starter bars that are supplemented by additional reinforcement added to the joining zone. All reinforcing elements may be applied in the precast yard, thus obviating the need to place individual reinforcing elements on site.

In an embodiment, the joining zone is arranged transversely of the bridge. Such an arrangement is likely to be required for all bridge constructions irrespective of the

18673373_1 (GHMatters) P100843.AU.1 28/04/22 overall width of the bridge because transverse joining zones would be necessary to join the girder units to the headstocks and/or abutments.

In an embodiment, the joining zone is arranged longitudinally of the bridge. Longitudinal joining zones are likely to be required where the width of the bridge is wider than the width of a modular girder unit. This is likely to occur, for example, where the bridge comprises greater than a single traffic lane.

In an embodiment, the joining zones are arranged both transversely and longitudinally of the bridge.

In an embodiment, all of the cured, reinforced stitches collectively provide a substantially water impermeable deck for the bridge. By "water impermeable" is meant that the cured reinforced stitches provide a physical barrier to the flow of water therethrough. This is an advantage over prior art bridges constructed from precast components which typically include openings or gaps at the joints between the components. The decks of these prior art bridges are therefore discontinuous. In contrast, the combination of precast modular components and reinforced stitches of the present modular bridge design provides a substantially continuous deck across the width and length of the bridge.

In an embodiment, all of the modular components are joined to each other using insitu casting of a curable material in the joining zones to provide a substantially continuous deck surface of the bridge. The continuous deck surface avoids the prior art disadvantage of mismatched levels of adjacent precast members and therefore improves rideability.

The curable material may comprise concrete.

In an embodiment, the modular components are joined to each other in the substantial absence of exposed steelwork in the joining zones. In this embodiment, the reinforcing elements are covered by the curable material in the joining zone and are

18673373_1 (GHMatters) P100843.AU.1 28/04/22 preferably sealed by the curable material. The absence of exposed steelwork in the joining zones reduces or eliminates deterioration of the joints and minimises the need for or frequency of bridge maintenance.

In an embodiment, the modular components are joined to each other in the substantial absence of exposed steelwork, such as bolts or dowels. The absence of exposed steelwork reduces deterioration of the joints and minimises the need for inspection and maintenance. The absence of exposed steelwork can be achieved because the steel reinforcement is embedded in concrete in the joining zones.

In an embodiment, the modular units are supported on, and rigidly connected to the substructure by insitu concrete stitching. The insitu stitching enables rigid connection to the substructure, thus avoiding the need for elastomeric bearings between the modular units and the substructure.

In an embodiment, the joining zone comprises a recess between adjacent modular components. The recess may be at least partly defined by opposing and/or adjacent walls of the modular components. The recess may be entirely defined by opposing and/or adjacent walls of the modular components. The insitu casting of a curable material in the joining zone can therefore be effected with minimum or no temporary formwork as the walls of modular components inherently provide formwork for the curable material. Formwork may be required at the abutments. The formwork may comprise a reusable modular steel form. It may be temporarily connected to the abutment beam using preformed dowel holes.

As previously stated, the bridge substructure typically comprises transverse concrete headstocks and abutment beams supported on precast concrete driven piles, or cast insitu bored piles. In an embodiment, the headstocks and/or abutment beams are joined to the piles by supplying a curable material, such as grout, to a gap there between, and allowing the curable material to harden. The gap may be downwardly opening. Temporary closure formwork may be provided at the entrance to the gap. An aperture may be provided in the formwork to allow the curable material to be pumped

18673373_1 (GHMatters) P100843.AU.1 28/04/22 into the gap. The aperture may comprise a nipple for attachment to a conduit through which grout is fed into the gap.

In an embodiment, the modular component is at least partially constructed from a concrete- steel composite material. The composite material may comprise steel fibres dispersed in a concrete matrix. In an embodiment, the steel fibres may have the following characteristics; Tensile strength: 2000 to 3000 MPa, such as 2500 Mpa; Length: 20 to 100 mm, preferably 35 to 75 mm, such as 65 mm long, Aspect ratio: 40 to 80, preferably 50 to 70, such as 60, Dosage 20-30 kg/m3 .

In a third aspect there is disclosed a method for construction of a bridge, including the steps: a. providing one or more modular components, each component comprising a precast concrete body having a first reinforcing element adapted to extend into a joining zone; b. positioning the or each component adjacent to a structure having a second reinforcing element adapted to extend into the joining zone, wherein the joining zone is at least partially defined by the modular component and the adjacent structure, the first and second reinforcing elements being offset and spaced with respect to each other to allow them to overlap and/or interleave and jointly provide substantially even reinforcement in the joining zone; c. providing a curable material in the joining zone to cover the first and second reinforcing elements; d. curing the curable material in the joining zone to produce a cured, reinforced joint (stitch) between the modular component and the adjacent structure.

The method for construction of a bridge may comprise a span-by span method. In this method, the precast concrete bodies that comprise girder units are positioned using a gantry in the positioning step (b).

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In a fourth embodiment there is provided a modular bridge constructed according to the method described above.

The disclosed system for construction of a bridge can provide one or more of the following characteristics; • All modular components may be essentially precast concrete, allowing factory controlled quality, and speedy erection. For example simple single span bridges located on the road alignment may require a road closure of only one week. The ability to reduce construction time translates into a reduction in the cost of construction as compared with a bridge with a composite cast insitu concrete deck. • The modular components can be joined together both transversely and longitudinally with cast insitu concrete stitching. This results in a more continuous deck surface and avoids the need for exposed steelwork to join the components. • In one embodiment, the precast modular components may be at least partially supplemented by steel fibres in the curable material mix. The presence of the steel fibres can reduce the amount of conventional reinforcement to be fabricated and placed, producing an overall saving in cost, and time. • The modular bridge system may be constructed without requiring reinforcing bars to be fixed on site. The reinforcing elements may be fixed in the modular components during precasting of the modular components. The reinforcing elements may, for example, comprise starter bars which are all fixed in the precast yard using simple jigs to provide the tolerances on location required. • The modular bridge system requires little or no formwork to be placed during construction. It may require a non-recoverable form (fixed in the precast yard) for the joins between modular components and a temporary simple straight steel modular form fixed into preformed dowel holes at the abutment beams.. In at least one embodiment, the modular bridge has no deck joints after it is constructed.

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• In at least one embodiment, the modular bridge requires no bearings as the modular units can be supported on, and rigidly connected to the substructure by insitu stitching. • In one embodiment, piles are connected to the cross heads and/or abutments using a grouted connection that obviates the need to expose the longitudinal reinforcement of the precast piles in the traditional way by extensive jack hammering of the concrete. • The system lends itself to erection using gantries, and therefore construction can avoid the use of a large crane. This is especially beneficial in remote areas.

BRIEF DESCRIPTION OF THE DRAWINGS Notwithstanding any other forms which may fall within the scope of the apparatus and method as set forth in the Summary, specific embodiments will now be described, by way of example only, with reference to the accompanying drawings in which: Figure 1 shows a perspective view of a modular bridge constructed using the system and method of the disclosure; Figure 2 shows a perspective view of modular components comprising two deck units and a headstock assembled for lateral connection; Figure 3(a) and (b) show two cross-sectional views of the assembled modular components of Figure 2; Figure 4 shows a perspective view of modular components comprising two deck units assembled for longitudinal connection; Figure 5 shows a cross sectional view of the modular components of Figure 4; Figure 6 shows a perspective view of assembled modular components comprising a deck unit and an abutment; and Figure 7 is a cross sectional view of the assembled modular units of Figure 6.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

In the following description of specific embodiments, like reference numerals refer to like parts.

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Figure 1 shows a perspective view of a modular bridge, 10, constructed using the system and method of the disclosure. The modular bridge 10 comprises a plurality of modular components indicated generally at 12. The modular components variously comprise girder units 14, headstock units 16 and abutment units 18. The headstock 16 units are supported on piles 20. The headstock units 16, supporting piles 20 and abutment 18 units collectively comprise the bridge substructure. The modular bridge 10 includes a lateral barrier 15 along each outer edge thereof. While the barrier shown in the drawings comprises concrete, it may instead be constructed from other materials, such as steel, or a combination of concrete and steel. The modular bridge 10 also includes transverse concrete stitches 34 and longitudinal concrete stitches 36, which together provide a substantially water impermeable deck 21 to the bridge 10. The barrier 15 may include drainage means (not shown) to allow water runoff from the bridge deck 21.

Referring now to Figures 2 and 3, each component 12 comprises a precast concrete body that is joinable to an adjacent structure via a joining zone 22 therebetween. In the embodiment shown, the "adjacent structure" comprises another modular component 12. The modular components 12 comprise girder units 14a and 14 b and a headstock unit 16. Each girder unit 14a and 14b includes a barrier element 15a and 15b, respectively, extending from an outer edge thereof. The barrier units collectively form lateral barriers 15 upon construction of the modular bridge 10. The joining zone 22 comprises a recess between and defined by the opposing lateral walls, 28 and 30 of the girder units 14a and 14b and the upper surface 32 of the headstock unit 16. The modular components 12 each have a respective reinforcing element 26a, 26b and 26c extending therefrom. The reinforcing elements 26a,b,c comprise steel reinforcing bars set within and extending from the precast concrete body. The reinforcing elements 26a,b,c are adapted to cooperate by being offset with respect to each other to allow them to overlap in the joining zone 22 and to jointly provide substantially even reinforcement in the joining zone. The modular components 12 are joined to each other by insitu casting of concrete in the joining zone 22 to provide a

18673373_1 (GHMatters) P100843.AU.1 28/04/22 cured, reinforced joint 34 (also termed herein "concrete stitch") which extends transversely of the bridge.

Figure 3 (a) and (b) also show a method of attachment of the headstock unit 16 to the pile 20. The headstock unit 16 includes a downwardly opening headstock recess 40 in the lower surface thereof. After the pile 20 has been installed the top of the pile is trimmed to the designated level and steel shear connectors 35 are drilled and epoxied into the concrete pile shaft near the top. The precast headstock unit 16 is then lowered onto the piles using shims 37 to provide the correct level. The headstock unit 16 and the pile 20 are attached to each other by supplying a curable material 48, such as grout, to the gap 42 between the headstock recess 40 and the pile 20 and allowing the curable material 48 to harden. Temporary closure formwork 44 is provided at the entrance to the gap 42. A nipple 46 is provided in the formwork to allow connection thereto of a conduit through which the curable material 48 can be pumped into the gap 42.

Figures 4 and 5 show another embodiment in which the modular components 112 comprise two girder units 114a and 114b (only partially shown) assembled for longitudinal connection. Similarly to the embodiment shown in Figures 2 and 3, the girder units 114a and 114b comprise precast concrete bodies that are joinable to each other via a joining zone 122 therebetween. Girder units 114a and 114b are intended to generally comprise laterally outer and inner parts, respectively, of the modular bridge when assembled. Girder unit 114a therefore includes a barrier element 115a extending from an outer edge thereof. The barrier element 115a may be of concrete and made integral with the girder unit 114a such that both form a unitary body. Alternatively, the barrier element 115a is of concrete it may be formed separately to the girder unit 114a, such as by precasting it and subsequently joining it to the girder unit 114a, or by casting it insitu on the girder unit using specialized formwork.

Also similarly to the embodiment of Figures 2 and 3, the joining zone 122 comprises a recess between and defined by the opposing lateral walls, 128 and 130 of the girder units 114a and 114b. The lateral walls each include a rebate 128a and 130a, respectively which together provide support for lower non-recoverable formwork such

18673373_1 (GHMatters) P100843.AU.1 28/04/22 as Fibre Reinforced Cement (FRC) sheet 138 Each girder unit 114a and 114b has a respective reinforcing element 126a, 126b extending therefrom. The reinforcing elements 126a,b comprise steel reinforcing bars set within and extending from the precast concrete body and are offset with respect to each other to allow them to overlap in the joining zone 122. The girder units 114a and 114b are joined to each other by insitu casting of concrete in the joining zone 122 to provide a cured, reinforced joint 136 (also termed herein "concrete stitch") which extends longitudinally of the bridge 10.

Figures 6 and 7 show a further embodiment in which the modular components 212 comprise a girder unit 214a and an abutment beam 218 for assembly at the ends of the modular bridge 210. Similarly to the embodiments shown in Figures 2 to 5, the modular components 212 comprise precast concrete bodies that are joinable to each other via ajoining zone 222 therebetween. The modular components 212 each have a respective reinforcing element 226a, 226b extending therefrom. The reinforcing elements 226a,b comprise steel reinforcing bars. In this embodiment, formwork 238 is required to complete a recess 222 for receiving concrete.

Whilst a number of specific embodiments have been described, it should be appreciated that the system, modular component, method and modular bridge may be embodied in many other forms.

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" and variations such as "comprises" or "comprising" are 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 apparatus and method as disclosed herein.

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Claims

CLAIMS The claims defining the invention are as follows

1. A system for construction of a bridge, comprising one or more modular components, each component comprising a precast concrete body that is joinable to an adjacent structure via a joining zone therebetween, the precast concrete body having a first reinforcing element adapted to extend into the joining zone and the adjacent structure having a second reinforcing element adapted to extend into the joining zone, the first and second reinforcing elements being offset and spaced with respect to each other to allow them to overlap and/or interleave and jointly provide substantially even reinforcement in the joining zone, the modular component being joinable to the adjacent structure by insitu casting of a curable material in the joining zone to cover the first and second reinforcing elements and, after curing of the curable material, to thereby produce a cured, reinforced joint (stitch) between the modular component and the adjacent structure.

2. The system of claim 1, wherein the modular component is a girder component.

3. The system of claim 1, wherein the modular component is a combined deck and girder component.

4. The system of any preceding claim, wherein an upper surface of such a modular component comprises a traffic carrying surface.

5. The system of any one of the preceding claims, wherein the adjacent structure is another modular component.

6. The system of claim 5, wherein the modular components have substantially the same configuration.

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7. The system of any one of claims 1 to 4, wherein the adjacent structure is a substructure for the bridge.

8. The system of any one of the preceding claims, wherein the first and second reinforcing elements are on adjacent sides of respective modular components.

9. The system of any one of the preceding claims, wherein the first and second reinforcing elements are overlapped and interleaved with respect to each other.

10. The system of any one of the preceding claims, wherein the first and second reinforcing elements comprise steel reinforcing bars that extend laterally from the modular component.

11. The system of claim 10, wherein thefirst and second reinforcing elements are laterally offset and spaced with respect to each other to avoid mutual interference.

12. The system of any one of the preceding claims, wherein the cured, reinforced stitch provides a substantially continuous, water impermeable deck for the bridge.

13. The system of any one of the preceding claims, wherein the modular components are joined to each other in the substantial absence of exposed steelwork in the joining zone.

14. The system of any one of the preceding claims, wherein the joining zone comprises a recess between one modular component and the adjacent structure and is at least partly defined by opposing and/or adjacent walls of the modular components.

15. The system of any one of the preceding claims, wherein the modular component is at least partially constructed from a concrete- steel composite material, preferably comprising steel fibres dispersed in a concrete matrix.

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16. The system of claim 15, wherein the steel fibres have a tensile strength from 2000 to 3000 MPa.

17. The system of claim 15 or 16, wherein the steel fibres have a length from 20 to 100 mm, preferably from 35 to 75 mm.

18. The system of any one of claims 15 to 17, wherein the steel fibres have an aspect ratio from 40 to 80, preferably from 50 to 70.

19. The system of any one of claims 15 to 18, wherein a concentration of the steel fibres in the concrete is from 20-30 kg/m3 .

20. A modular component for use in a system for construction of a bridge, the modular component comprising a precast concrete body that is joinable to an adjacent structure via a joining zone therebetween, the precast concrete body having a first reinforcing element adapted to extend into the joining zone and the adjacent structure having a second reinforcing element adapted to extend into the joining zone, wherein, in use, the first and second reinforcing elements are offset and spaced with respect to each other to allow them to overlap and/or interleave and jointly provide substantially even reinforcement in the joining zone, the modular component being joinable to the adjacent structure by insitu casting of a curable material in the joining zone to cover the first and second reinforcing elements and, after curing of the curable material, to thereby produce a cured, reinforced joint (stitch) between the modular component and the adjacent structure.

21. A method for construction of a bridge, including the steps: a. providing one or more modular components, each component comprising a precast concrete body having a first reinforcing element adapted to extend into a joining zone; b. positioning the or each component adjacent to a structure having a second reinforcing element adapted to extend into the joining zone, wherein the joining zone is at least partially defined by the modular component and the

18673373_1 (GHMatters) P100843.AU.1 28/04/22 adjacent structure, the first and second reinforcing elements being offset and spaced with respect to each other to allow them to overlap and/or interleave and jointly provide substantially even reinforcement in the joining zone; c. providing a curable material in the joining zone to cover the first and second reinforcing elements; d. curing the curable material in the joining zone to produce a cured, reinforced joint (stitch) between the modular component and the adjacent structure.

22. The method for construction of a bridge according to claim 21, comprising a span-by span method.

23. A bridge constructed using the method of claim 21.

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