Technical Information and Accreditations

The FlexiArch is a modern, patented, arch bridge system which references the construction principles and performance of a traditional masonry arch bridge.It’s uses include:-Spans up to 15m *Multiple SpansSkew Spans **Double Radius ***Culverting of long streamsStrengthing of the existing bridges

* Spans between 15m and 20m are currently being developed

** Skew Span is currently under development

*** Double Radius is now available

The system is the result of collaboration between Queen’s University, Belfast’s School of Civil Engineering and specialist precast manufacturer Macrete.

Approvals: Multiple AIP’s from UK County Councils

Design: BD/91 and BS EN 1991

Loading: Full Highway Loading as per BS EN 1991 including SV vehicles.

Material: Unreinforced 50N Concrete in Arch Units to BS 8500 and

BS EN 206 Part 1:2000

Finishes: Plain, patterned, stone or brick

Widths: Available to any road width in 1m width arch ring units

Manufacture: BS EN ISO 9001: 2008

The installation process was straightforward, went to plan, and was quick.

Andrew Broad, General Works Manager, Dean & Dyball Civil Engineering (Escot Estate FlexiArch Installation - two bridges)

The FlexiArch was chosen for the Newtownabbey cycle path project because of its aesthetic suitability, economic deployment, sustainable construction and consideration for environmental issues such as avoidance of disturbance to the river bed.

Neil Luney, Rural Project Officer, Newtownabbey Borough Council (National Cycle Path development on rural land - three bridges)

The procurement, delivery and erection of the pre cast units was extremely efficient. Merthyr Tydfil CBC and the general public have expressed extreme satisfaction with the completed structure.

Mark Robinson, Merthyr Tydfil County Borough Council (River Taff Corridor Improvements - one bridge)

The flexi-arch system and installation process completely suited this location for replacement of an old arch bridge. There are definitely other locations within the county where this will be seriously considered as an appropriate solution for bridge replacement.

Mladen Dragojlovic, Gloucestershire County Council (Country lane river crossing - bridge replacement)

FlexiArch can be ordered from:

Macrete Ireland Limited, 50 Creagh Road, Toomebridge, Co. Antrim, N. Ireland BT41 3SE

T: +44 (0)28 796 504 71 F: +44 (0)28 796 500 84

E: info@macrete.com www.macrete.com

FlexiArch specialist contact: Abhey Gupta

The sustainable option for new crossings and bridge replacement

FlexiArch customers include:

Bedfordshire HighwaysCapita SymondsDRD NI Roads ServiceFP McCann LimitedGloucestershire Highways Herefordshire County CouncilJN Bentley LimitedLagan Construction LimitedLancashire County CouncilMerthyr Tydfil County Council

FlexiArch allowed us to quickly erect the superstructure elements and to minimise working in the watercourse, which was badly e-coli contaminated. The new arch structure suited the rural environment and the heritage brick facework produced an attractive finished bridge.John Gatheral, Lancashire County Council

For further FlexiArch information, including photographic examples of installations, please visit our website.

Newtownabbey Borough CouncilNorth Lanarkshire CouncilShropshire County CouncilSligo County CouncilSouth Gloucestershire County CouncilSSE RenewablesStaffordshire County CouncilStuart Michael Associates

Q. What is FlexiArch?A. FlexiArch is a modular, precast, concrete arch bridge system

invented by Professor Adrian Long at Queen’s University Belfast. Commercial development is by Macrete.

Q. How does it work?A. The FlexiArch system replicates a stone masonry arch

bridge but is precast. Individual tapered precast blocks are connected by a polymeric flexible membrane allowing the arch to form as it is lifted from the transporter.

Q. Where can I use it?A. FlexiArch can be used for any kind of new crossing or

Highway bridge replacement for up to 20m span.

Q. How wide is it?A. Arch rings are made as 1m widths so any final width is possible.

Q. How does it arrive on site?A. The bridge arrives on site flatpacked on transporters.

The components will include flexible arch rings springing blocks and spandrels which can be with or without decorative finish.

Q. What is the construction process?A. With foundations and footings constructed in advance, each

arch ring is installed, usually in one session. The spandrels are fitted and secured. Typical time for installation is 4 to 6 hours. The arch is backfilled, leveled, and blacktopped. Spandrels are finished to environmental requirements.

Q. You say it is “sustainable”?A. FlexiArch is not internally reinforced. It is a compression

structure, self supported by its own weight without the aid of mortar. With no rebar content, the possibility for internal corrosion, expansion, cracking or spalling is eliminated.

Double Radius FlexiArch the new development of FlexiArch for rail and roadThe limitations of a standard arch bridge relate to

the usable through width as determined by its span

and rise. While this is not significant to a bridge

crossing over a brook or a limited width river, it is a

stumbling block for a bridge required to pass over

two lanes of highway, or two tracks of rail.

The FlexiArch solution to this problem is the

Double Radius FlexiArch (Flexi DR).

Span range is from 8m – 15m; capacity is Full

Highway Loading; applications include road over

rail, road over road and road over waterway.

Installations will be commencing from winter 2011.

Please contact Abhey Gupta for

further information.

Flax Lane Road Bridge, Burscough, LancashireLancashire County Council have installed a FlexiArch crossing at Abbey Brook, Burscough as a replacement for a failed bridge.

The new bridge which has a span of 8.3m and a width of 6m, crosses a fast moving water course which has the capacity to swell significantly following heavy rainfall.

The spandrels were faced with brick after installation. All the construction work was carried out by Lancashire County Commercial Group in conjunction with their Area South Design Team.

15m span heavy vehicle access crossings for Griffin Wind Farm, Perthshire A total of three FlexiArch bridges have been installed to provide site access for abnormally heavy load transporters. Installation was by Lagan Construction Group who are the main contractors. The project is the Griffin Wind Farm, presently being constructed in Perthshire.

The bridges are standard FlexiArch units without special reinforcement additions. The spandrels were installed without cosmetic additions as these bridges are not intended for permanent or public road access.

The bridges comprise of Tombane Burn, a 5.2m span, with a rise of 1.75m and width of 8m. The second - Ballinloan Burn, span 15m, rise 3m and width 5m. The third - Pitleoch Burn, span 8.4m, rise 2.8m, width 5m.

The abnormal loads comprise of generators, blades and mast components and all other construction materials for the project.

FlexiArch jacked beneath existing service ductsA 4m span, 7m wide FlexiArch was installed beneath existing service ducts, by Gloucestershire Highways as a replacement road over river bridge on South Cerney Road, south of Cirencester, known as Siddington House Bridge.

The existence of three steel service ducts prevented easy craning of arch rings on to their springing blocks, and instead, a system of jacking under the service ducts was employed.

Arch rings were lowered into the available central space between a pair of service ducts and then slid horizontally on greased blocks by use of a pair of hydraulic bottle jacks exerting force upon the lowest blocks of the arch ring.

A total of seven 1m width arch rings were placed in this way to form the basic arch of the bridge. Single piece spandrels were added - one to either side of the structure. The arch was then backfilled to road level and the spandrels clad with local stone to replicate the appearance of the original bridge.