Box CulvertsDrainage & Water Management

Precast Concrete Solutions

v.2.0

FP McCann is the UK’s market leader in the manufacture, supply and delivery of precast concrete solutions. Our comprehensive precast concrete business extends to include:

Drainage and Water Management Solutions • Tunnel and Shaft Solutions Rail Solutions • Power and Infrastructure Solutions • Walling Solutions Fencing Solutions • Modular Building Solutions • Agricultural Solutions Flooring Solutions • Specialist Precast Solutions

Modern manufacturing plants at Alnwick (Northumberland), Byley (Cheshire), Cadeby (Warwickshire), Drakelow (Staffordshire), Ellistown (Leicestershire), Grantham (Lincolnshire), Lisnaskea (Northern Ireland), Littleport (Cambridgeshire), Lydney (Gloucestershire), Magherafelt (Northern Ireland), Telford (Shropshire) and Weston Underwood (Derbyshire) incorporate the latest computerised batching, distribution, casting, curing and handling systems and are operated by skilled and experienced workforces to ensure consistency of quality. Their geographical spread gives us an unrivalled ability to serve the construction industry throughout the UK and Ireland.

fpmccann.co.uk

Lydney

Magherafelt

Cadeby

Drakelow

Grantham

Littleport

Alnwick

Weston UnderwoodEllistown

Byley

Telford

Lisnaskea

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Benefits of Box Culverts

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Designed and manufactured in accordance with all current design specifications and relevant standards, FP McCann’s box culverts are available in span sizes from 1000mm to 5400mm and internal heights from 500mm to 3600mm, dependent on the final mould configuration adopted. A bespoke CAD design service is also available where non-standard unit sizes can be accommodated, along with any other internal features requested by the client.

Using a modern production facility at Telford, Shropshire, FP McCann’s experienced engineers and detailing team, have the flexibility to quickly respond to meet any design criteria and deliver nationally to just-in-time requirements.

Supplied in either single or multiple runs, the use of precast concrete box sections in civil engineering projects is wide-ranging, from their use for directing watercourses to the provision of attenuation tanks and underpasses. FP McCann is a member of the Box Culvert Association (BCA) and their products comply with all relevant standards, as set out in accordance with BS ISO 9001 and ISO 14001.

Structural strength and long life performanceOur durable box culvert system meets the design life requirements for buried structures. Minimum maintenance is required.

Ease of installationFP McCann’s box culverts can be easily positioned in shallow or deep fill installations.

Flexible sizes and internal featuresOur box culverts can be manufactured in a range of sizes and accommodate features such as dry weather flow channels, mammal ledges and dual cell configuration units, plus tapered and skewed units, if required.

Additional Features End walls, access points, vent holes, inlets, outlets, rungs, angles and splayed ends can all be added to any culvert, as per requirement. Starter bars and sockets can be added to facilitate any additional casting on-site, which may be required as part of the finished work.

Box Culvert Applications• Attenuation and storage tanks• Water course diversion• Open channels• Road crossings• Pedestrian and vehicle subways• Shafts• Service tunnels and ducts• Conveyor protection

The proven strength and performance characteristics of precast concrete box culverts, together with their excellent service life, make them ideal for a wide variety of civil engineering and construction applications. Box culvert sections can be manufactured in a variety of shapes and sizes, offering exceptional versatility in the uses to which they can be applied. In addition to the more common use for diverting water courses, box culverts have been used in an array of applications including balancing tanks, pedestrian subways, access shafts, service tunnels, sea outfalls, road crossings and many other situations where the whole life costing consideration requires strength, durability and economy to be of paramount importance.

Unlike other materials, such as steel, precast concrete box culverts do not require additional treatments to prolong their life or improve performance. The concrete surface will not rust and the smooth internal finish of the box culvert ensures optimum flow of water through the concrete structure.

Box Culvert types and InstallationGuidelines

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Precast concrete box culverts fulfil the current design life requirements for buried structures. The ability to provide many years of service with the minimum of maintenance makes precast concrete box culverts the most cost -effective means of diverting water course, especially with the ever present risk of corrosive elements in the water or soil.

Whilst the methods and procedures for the installation of precast concrete box culverts are familiar to contractors, careful attention to detail will lead to safer working, a smoother flow of operations and a higher standard of finished culvert.

Box Culvert installation and jointing details can be downloaded from fpmccann.co.uk/drainage

This guide provides a reliable checklist for anyone engaged in the installation of box culverts. It is published to encourage good practice in the use of precast box culverts.

SpecialsBespoke units accommodating a variety of features can be manufactured to the customers design requirements.

Side pipe entry Integral or bolt on end wall

Access opening

Benching Combined with either a channel or cast as a “vee”, benching improves self-cleansing flow rates

Mammal LedgesCast-in mammal ledges allow access through the culvert to wildlife without the requirement for extra site provisions

ChannelsHalf round (or equivalent) channels can be cast into the floor of the units at any position, with a choice of equivalent half round diameters.

Typical CulvertUnits are available in internal span sizes from 1000mm to 5400mm and internal heights from 500mm to 3600mm, with unit lengths to a maximum of 2000mm dependent on final mould configuration (please refer to internal dimensions chart).

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Box Culverts

Internal Dimensions(Based on flat invert culvert units)Key: Flow area m2 / Discharge rate m3/sec

Please note: These figures are a guide only and will be dependent on the mould configuration used in manufacture. Discharge rates are calculated using Colebrooke-White equation for a fully wetted perimeter under uniform flow conditions and assuming a flat invert culvert unit. The assumed laying gradient (s) is 1:1000 with a roughness co-efficient (k) of 0.3. Where different values maybe required, please contact the office number below to discuss your specific requirements.

Width mm (internal span)

Inte

rnal

hei

ght m

m

1000 1200 1500 1800 2100 2400 2700 3000 3300 3600 3900 4200 4500 4800 5100 5400

500 0.460.40

0.560.51

0.710.67

0.860.84

1.011.00 - - - - - - - - - - -

600 0.560.53

0.680.67

0.860.89

1.041.11

1.221.33 - - - - - - - - - - -

650 0.610.60

0.740.76

0.931.00

1.131.25

1.321.50

1.521.75

1.712.00 - - - - - - - - -

800 0.760.81

0.921.03

1.131.33

1.371.67

1.612.01

1.852.36

2.092.71

2.333.06

2.573.42

2.813.77

3.054.12 - - - - -

1000 0.961.10

1.161.40

1.431.84

1.732.32

2.032.80

2.333.29

2.633.79

2.934.29

3.234.79

3.535.30

3.835.80

4.136.30

4.436.81

4.737.32 - -

1200 - 1.371.76

1.732.37

2.093.00

2.453.64

2.814.29

3.174.95

3.535.61

3.896.28

4.256.95

4.617.62

4.978.29

5.338.97

5.699.64

6.0510.32

6.4111.00

1500 - - 2.183.21

2.634.09

3.084.98

3.535.89

3.986.81

4.437.74

4.888.68

5.339.62

5.7810.57

6.2311.52

6.6812.48

7.1313.44

7.5814.40

8.0315.37

1800 - - - 3.175.21

3.716.38

4.257.57

4.798.78

5.3310.00

5.8711.24

6.4112.48

6.9513.74

7.4915.00

8.0316.27

8.5717.54

9.1118.82

9.6520.10

2100 - - - - 4.347.83

4.979.31

5.6010.83

6.2312.36

6.8613.92

7.4915.49

8.1217.07

8.7518.67

9.3820.27

10.0121.89

10.6423.50

11.2725.13

2400 - - - - - 5.6911.11

6.4112.94

7.1314.81

7.8516.70

8.5718.62

9.2920.55

10.0122.50

10.7324.46

11.4526.44

12.1728.42

12.8930.41

2700 - - - - - - 7.2215.11

8.0317.32

8.8419.57

9.6521.84

10.4624.14

11.2726.46

12.0828.80

12.8931.16

13.7033.53

14.5135.91

3000 - - - - - - - 8.9319.89

9.8322.50

10.7325.15

11.6327.83

12.5330.54

13.4333.27

14.3336.03

15.2338.80

16.1341.59

3300 - - - - - - - - 10.8225.49

11.8128.52

12.8031.60

13.7934.71

14.7837.86

15.7741.03

16.7644.22

17.7547.43

3600 - - - - - - - - - 12.8931.96

13.9735.44

15.0538.97

16.1342.53

17.2146.13

18.2949.76

19.3753.42

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Installation GuidelinesFor installation and jointing details, refer to the Box Culvert Association’s ‘Guide to Site Practice’ which can be downloaded from the BCA’s website, www.boxculvert.org.uk

Design Criteria Design loading criteria is generally specified by the scheme engineer and ideally should include, as a minimum, the information below:

• Internal span• Internal height• Metres required• Number of runs• Minimum depth of fill over the culvert unit• Maximum depth of fill over the culvert unit• Culvert usage• Surface loading conditions : green field, highway etc• Invert type

Exposure conditions should be specified and, where available, design codes provided. Further design requirements may be required for inlet/outlet points, access holes and end walls.

Weston Underwood Office:Bullhurst LaneWeston UnderwoodDerbyshireDE6 4PH

T 01335 361269F 01335 361410precast@fpmccann.co.uk

Drainage and Water Management Solutions Ellistown 01530 240000 / Magherafelt 028 7954 9026

Tunnel and Shaft Solutions Cadeby 01455 290780

Rail Solutions Cadeby 01455 290780

Power and Infrastructure Solutions Cadeby 01455 290780

Walling Solutions Grantham 01476 562277 Lydney 01594 847500

Fencing SolutionsCadeby 01455 290780

Agricultural SolutionsLydney 01594 847500 Magherafelt 028 7954 9026

Modular Building Solutions Grantham 01476 562277 Byley 01606 843500

Flooring Solutions Weston Underwood 01335 361269

Specialist Precast Solutions Littleport 01353 861416 fpmccann.co.uk