helically corrugated steel pipes helcor & … · helically corrugated steel pipes helcor and...

HelCor®& HelCor PA®HELICALLY CORRUGATED STEEL PIPES

HELCOR druk_geosyntetyki II.qxd 2012-09-28 13:22 Strona 2

Table of Contents

2

3

4

5

6

8

13

14

16

18

19

20

22

24

26

1. Applications

2. Steel

3. Plate thickness and corrugation types

4. Production

5. Section lengths and coupling bands

6. Geometric and hydraulic parameters

7. Tolerances

8. Durability

9. Pipe end finishing

10. Fittings

11. Cover depth

12. Bedding and backfilling

13. Structural design

14. Installation and construction procedures

15. Other applications

1.www.viacon.pl

1. Introduction

3.www.viacon.pl

The history of corrugated steel pipes dates back to 1896, when its production was started in the United States.

The first helically corrugated steel pipes were also produced at that time in Russia, where 1300 m of this product was used as culverts under the railway

lines. In Poland, the pipes appeared at the end of the 1970s , and since then they have been increasingly popular among designers and contractors.

Helically corrugated steel pipes HelCor and pipe-arches HelCor PA pro-

duced by ViaCon make up complete systems used in civil engineering as:

- roads and railway culverts

- underground passages

- ecological passages

- hydro technical structures

- relining of existing old structures

Complete system of helically corrugated pipes

includes elbows or T-connections and also

additional elements such as manholes, inspection

chambers etc.

According to the European Standard PN-EN 1991-

2:2007 HelCor and HelCor PA pipes can be used as

engineering structures for every class of road and

railway (up to V=200km/h) load.

HelCor and HelCor PA pipes have Technical

Approval issued by Polish Road and Bridge Research

Institute (IBDiM). They have been approved for use in

Scandinavia, The Baltic States, Switzerland,

Hungary, Slovakia, The Czech Republic, Romania, Austria, The Ukraine,

Belorus and other European countries. HelCor and HelCor PA are

approved by Polish Central Mining Institute (GIG) to be used on subsi-

dence areas.

Installation time for HelCor and HelCor PA is much shorter then for

concrete pipes. Easy and quick assembly helps in limiting time for

construction of culverts or other structures and allows to construct culvert

in stages without stopping the traffic as well as during winter time.

Construction of culverts with the use of HelCor and HelCor PA is much

cheaper than traditional concrete culverts.

Pipes are produced in Rydzyna (PL) and are delivered to many European

countries.

1. Applications

2.

3.www.viacon.pl

2. Steel

Steel used for the production of HelCor and HelCor PA pipes, as well as coupling bands

conform to the European Standards:

- EN 10327:2006 “Continuously hot-dip coated strip and sheet of low carbon steels for

cold forming – Technical delivery conditions”

- EN 10326:2006 “Continuously hot-dip coated strip and sheet of structural steels -

Technical delivery conditions”

- 600 g/m2 zinc coating both sides, equivalent to 42μm on each side

- 1000 g/m2 zinc coating both sides, equivalent to 70μm on each side

- 600 g/m2 zinc coating both sides, equivalent to 42μm on each side, with

an additional 250μm polymer film (TrenchcoatTM or W-Protect®) on one

or both sides

Steel is delivered in coils, with a protection coating in accordance to a/m standards:

EN-10327

EN-10326

[MPa]

-

250

[MPa]

270 - 500

330

[%]

22

19

DX51D

S250GD

Standard Yield point Re Tensile strength Rm

HelCor and HelCor PA pipes steel mechanical properties

Elongation A80minSteel grade

3. Plate thickness and corrugation types

4.

HelCor and HelCor PA pipes are produced from steel strips with thickness ranging from 1,25mm to 3,5mm in two types of corrugation

- D1 - 68 x 13 mm

- D3 - 125 x 26 mm

Area of sectionA

Moment of InertiaIx

Section ModulusWx

Area of sectionA

Moment of InertiaIx

Section ModulusWx

Sectional properties of corrugated steel

Corrugation 68 x 13 [mm] Corrugation 125 x 26 [mm]

[mm] [mm2/mm] [mm4/mm] [mm3/mm] [mm2/mm] [mm4/mm] [mm3/mm]

Plate thickness

1,62

2,16

2,70

2,92

3,24

3,78

31,5

40,9

52,0

56,2

64,0

74,7

4,4

5,6

6,8

7,3

8,0

9,3

1,66

2,21

2,77

2,99

3,32

3,88

142,8

190,9

239,9

259,1

289,0

337,2

10,4

13,7

16,7

18,1

19,7

23,0

1,5

2,0

2,5

3,0

2,7

3,5

4. Production

5.

HelCor pipes are produced by cold forming of the steel strip into a round corrugated

shape with diameters ranging from 300mm to 3600mm. During forming of the pipe

a lock-seam is performed to keep the pipe integrity.

HelCor Pipe Arches are produced through controlled mechanical deformation of HelCor pipes with the use of hydraulic jacks.

www.viacon.pl

5. Section lengths and coupling bands

6.

The standard lengths of HelCor pipes are 6m, 7m and 8m, however the production process allows the manufacturing of any

length of pipe.

The pipe-arches are produced in 6m long segments from HCPA-01 to HCPA-20 and 7m and 8m long segments from HCPA-

21 to HCPA-50.

Typically the pipes are bevel cut in factory in accordance with the design to conform the slope and the skew angle. Cut ends

are protected against corrosion. In order to obtain the designed length of the pipe, several segments are joined with coupling

bands.

The coupling bands are made out of flat or corrugated steel. Depending on the diameter and purpose of the pipe, different

types and widths of coupling bands are used.

TYPE 1: flat connected by bolts – for diameters 300-1400 mm

TYPE 2: helically corrugated connected by bolts – for diameters 300–3600 mm

TYPE 3: helically corrugated connected by bolts in tubes (for relining)

TYPE 4: annular corrugated for connection of pipes with re-corrugated ends

7.

Coupling band diameter for HelCor pipes and dimensions for

HelCor PA depend on pipe diameter or span/rise of pipe arch

cross section.

TYPE 1 TYPE 4TYPE 2 TYPE 3

Coupling band type Width[mm]

Tolerance[%]

TYPE 1

TYPE 2

TYPE 3

TYPE 4

345 to 729

350 to 800

350 to 800

330

Acc to EN 10143:1997

±2%

±2%

±2%

For HelCor PA pipes only helically corrugated coupling bands (TYPE 2 or TYPE 3) are used.

Coupling bands dimensions and tolerances

www.viacon.pl

6. Geometric and hydraulic parameters

8.

Thickness parameters for respective diameters/dimensions of HelCor and HelCor PA pipes are given in the table below.

Standard plate thickness is shown with bold, but it is possible to manufacture a pipe of a different plate thickness.

Standard plate thickness is calculated for A Class of live load acc to Polish Bridge Standard PN-85/S-10030 (4 x 200kN x 1,5

factor = 1200KN, four axis vehicle), with minimum cover calculated as shown in chapter 11 of this catalogue. If other live load

is expected, plate thickness should be checked assuming respective standard requirements. For more details or other

solutions please contact the ViaCon technical department or your local dealer / representative.

HelCor Pipes

Diameter

[mm]

Cross sectionarea[m2]

CorrugationPlate thickness*

[mm]

Zinc coatingZinc coating

+ TrenchcoatTM layer

300

400

500

600

700

800

900

1000

1100

1200

1300

1400

1500

1600

1700

1800

1900

2000

2100

2200

2300

2400

2500

2600

2700

2800

2900

3000

3100

3200

3300

3400

3500

3600

0,07

0,12

0,19

0,28

0,38

0,50

0,63

0,79

0,95

1,13

1,32

1,54

1,76

2,01

2,27

2,54

2,83

3,14

3,46

3,80

4,15

4,52

4,91

5,30

5,72

6,15

6,60

7,06

7,55

8,04

8,55

9,08

9,62

10,18

D1

D1

D1

D1

D1

D1

D1

D1 / D3

D1 / D3

D1 / D3

D1 / D3

D1 / D3

D1 / D3

D1 / D3

D1 / D3

D1 / D3

D3

D3

D3

D3

D3

D3

D3

D3

D3

D3

D3

D3

D3

D3

D3

D3

D3

D3

1,5

1,5

1,5

1,5 / 2,0

1,5 / 2,0

1,5 / 2,0

1,5 / 2,0

1,5 / 2,0 / 2,5

2,0 / 2,5

2,0 / 2,5

2,0 / 2,5

2,0 / 2,5 / 3,0

2,0 / 2,5 / 3,0

2,0 / 2,5 / 3,0

2,0 / 2,5 / 3,0

2,5 / 3,0 / 3,5

2,5 / 3,0 / 3,5

2,5 / 3,0 / 3,5

2,5 / 3,0 / 3,5

2,5 / 3,0 / 3,5

2,5 / 3,0 / 3,5

2,5 / 3,0 / 3,5

3,0 / 3,5

3,0 / 3,5

3,0 / 3,5

3,0 / 3,5

3,0 / 3,5

3,0 / 3,5

3,5

3,5

3,5

3,5

3,5

3,5

Weight[kg/m]

Plate thickness*[mm]

Weight[kg/m]

13,0

17,3

21,7

34,7

40,5

46,2

52,0

57,8

63,6

69,4

75,1

106,5

114,1

121,7

129,3

164,3

173,5

182,6

191,7

200,8

210,0

219,1

266,3

276,9

287,6

298,2

308,9

319,5

330,2

340,8

351,5

362,1

372,8

383,4

1,6

1,6

1,6

1,6 / 2,0

1,6 / 2,0

1,6 / 2,0

1,6 / 2,0

1,6 / 2,0 / 2,5 / 2,7

2,0 / 2,5 / 2,7

2,0 / 2,5 / 2,7

2,0 / 2,5 / 2,7

2,0 / 2,5 / 2,7

2,0 / 2,5 / 2,7

2,0 / 2,5 / 2,7

2,0 / 2,5 / 2,7

2,5 / 2,7 / 3,0 / 3,5

2,5 / 2,7 / 3,0 / 3,5

2,7 / 3,0 / 3,5

2,7 / 3,0 / 3,5

2,7 / 3,0 / 3,5

2,7 / 3,0 / 3,5

2,7 / 3,0 / 3,5

3,0 / 3,5

3,0 / 3,5

3,0 / 3,5

3,0 / 3,5

3,0 / 3,5

3,0 / 3,5

3,5

3,5

3,5

3,5

3,5

3,5

14,4

19,2

24,0

35,7

41,7

47,7

53,6

59,6

65,5

71,5

77,4

109,1

116,9

124,7

132,5

167,7

177,0

186,3

195,6

205,0

214,3

223,6

271,0

281,8

292,6

303,5

314,3

325,1

336,0

346,8

357,7

368,5

379,3

390,2

9.

HelCor PA Pipes

Span / rise[m]Type


Corrugation

1,34/1,05

1,44/0,97

1,49/1,24

1,62/1,10

1,65/1,38

1,80/1,20

1,80/1,50

1,84/1,39

1,84/1,48

1,89/1,55

1,91/1,46

1,95/1,32

2,01/1,59

2,04/1,49

2,10/1,45

2,10/1,55

2,14/1,64

2,16/1,62

2,20/1,71

2,23/1,68

2,28/1,70

2,35/1,77

2,35/1,73

2,37/1,83

2,48/1,79

2,49/1,83

2,55/1,86

2,58/1,94

2,60/1,93

2,75/1,95

2,76/2,05

2,80/2,01

2,84/2,02

2,95/2,04

2,96/2,16

2,97/2,00

3,08/2,08

HCPA-01

HCPA-02

HCPA-03

HCPA-04

HCPA-05

HCPA-06

HCPA-07

HCPA-08

HCPA-09

HCPA-10

HCPA-11

HCPA-12

HCPA-13

HCPA-14

HCPA-15

HCPA-16

HCPA-17

HCPA-18

HCPA-19

HCPA-20

HCPA-21

HCPA-22

HCPA-23

HCPA-24

HCPA-25

HCPA-26

HCPA-27

HCPA-28

HCPA-29

HCPA-30

HCPA-31

HCPA-32

HCPA-33

HCPA-34

HCPA-35

HCPA-36

HCPA-37

1,13

1,10

1,46

1,42

1,82

1,70

2,15

2,04

2,16

2,32

2,23

2,04

2,55

2,41

2,42

2,59

2,74

2,80

2,99

2,93

3,03

3,28

3,16

3,45

3,47

3,61

3,73

3,97

3,97

4,20

4,48

4,43

4,58

4,69

5,06

4,57

4,94

D1

D1

D1

D1

D1

D1

D1

D1

D1

D1

D1

D1

D1

D1

D1

D1

D1

D1

D1

D1

D3

D3

D3

D3

D3

D3

D3

D3

D3

D3

D3

D3

D3

D3

D3

D3

D3

2,0 / 2,5

2,0 / 2,5

2,0 / 2,5

2,0 / 2,5

2,0 / 2,5

2,5 / 3,0

2,5 / 3,0

2,5 / 3,0

2,5 / 3,0

2,5 / 3,0

2,5 / 3,0

2,5 / 3,0

2,5 / 3,0

2,5 / 3,0

2,5 / 3,0

3,0

3,0

3,0

3,0

3,0

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

86,7

87,4

98,3

97,5

109,1

130,9

143,0

140,4

143,9

149,1

147,4

142,2

156,9

153,5

156,9

158,7

166,5

166,5

169,9

169,9

214,1

219,4

217,3

219,4

227,9

230,1

234,3

240,7

240,7

250,8

255,6

255,6

258,8

267,3

271,6

265,2

274,8

88,8

89,6

100,7

99,9

111,8

133,6

146,0

143,3

146,9

152,2

150,4

145,1

160,1

156,6

160,1

161,9

169,9

169,9

173,4

173,4

217,8

223,3

221,1

223,3

231,9

234,1

238,4

244,9

244,9

255,2

260,1

260,1

263,4

272,0

276,4

269,9

279,6

2,0 / 2,5 / 2,7

2,0 / 2,5 / 2,7

2,0 / 2,5 / 2,7

2,0 / 2,5 / 2,7

2,0 / 2,5 / 2,7

2,5 / 2,7 / 3,0

2,5 / 2,7 / 3,0

2,5 / 2,7 / 3,0

2,5 / 2,7 / 3,0

2,5 / 2,7 / 3,0

2,5 / 2,7 / 3,0

2,5 / 2,7 / 3,0

2,5 / 2,7 / 3,0

2,5 / 2,7 / 3,0

2,5 / 2,7 / 3,0

2,7 / 3,0

2,7 / 3,0

2,7 / 3,0

2,7 / 3,0

2,7 / 3,0

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5




Weight[kg/m]


Weight[kg/m]

www.viacon.pl

10.

* Plate thickness tolerances acc. to EN 10143:1997.

3,14/2,27

3,17/2,06

3,23/2,12

3,23/2,15

3,28/2,17

3,33/2,23

3,33/2,39

3,35/2,19

3,38/2,25

3,49/2,27

3,52/2,49

3,65/2,39

3,67/2,61

HCPA-38

HCPA-39

HCPA-40

HCPA-41

HCPA-42

HCPA-43

HCPA-44

HCPA-45

HCPA-46

HCPA-47

HCPA-48

HCPA-49

HCPA-50

5,63

5,12

5,41

5,39

5,67

5,97

6,29

5,65

5,60

6,28

6,91

6,85

7,52

D3

D3

D3

D3

D3

D3

D3

D3

D3

D3

D3

D3

D3

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

288,6

279,1

285,4

288,6

289,7

298,2

305,7

297,2

300,9

306,8

319,5

323,8

336,6

293,7

284,0

290,5

293,7

294,8

303,5

311,1

302,4

306,2

312,1

325,1

329,5

342,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

3,5

For the same water level the pipe-arch shape has 65% - 100% better water flow capacity than a round

pipe with the same rise.

HelCor PA Pipes

Span / rise[m]Type


CorrugationPlate thickness*

[mm]



Weight[kg/m]


Weight[kg/m]

11.

Hydraulic parameters

The

abov

e ta

ble

show

s th

e re

fere

nce

wat

er fl

ow Q

mfo

r H

elC

or p

ipes

with

wat

er le

vel a

t 75%

hei

ght b

ut a

t lea

st 2

5 cm

from

the

crow

n, a

ccor

ding

to P

olis

h na

tiona

l

regu

latio

ns.

Wat

er-fl

ow r

egul

atio

ns m

ay d

iffer

slig

htly

dep

endi

ng o

n na

tiona

l st

anda

rds.

For

mor

e de

tails

or

othe

r so

lutio

ns p

leas

e co

ntac

t th

e V

iaC

on t

echn

ical

depa

rtm

ent o

r yo

ur lo

cal d

eale

r /

repr

esen

tativ

e.

www.viacon.pl

12.

Hydraulic parameters

The

abov

e ta

ble

show

s th

e re

fere

nce

wat

er f

low

Qm

for

Hel

Cor

PA

pip

es w

ith w

ater

leve

l at

75%

hei

ght

but

at le

ast

25 c

m f

rom

the

cro

wn,

acc

ordi

ng t

o P

olis

h

natio

nal

regu

latio

ns.

Wat

er-fl

ow r

egul

atio

ns m

ay d

iffer

slig

htly

dep

endi

ng o

n na

tiona

l st

anda

rds.

For

mor

e de

tails

or

othe

r so

lutio

ns p

leas

e co

ntac

t th

e V

iaC

on

tech

nica

l dep

artm

ent o

r yo

ur lo

cal d

eale

r /

repr

esen

tativ

e.

13.

7. Tolerances

Manufacturing tolerance of HelCor

and HelCor PA length is ±0,5% of the

designed length.

A gap between two pipes connected

with a coupling band should not

exceed 30 mm.

Parameter Unit Acceptable tolerance

Diameter deviation % of nominal diameter

% of pipe diameterDiameter deformationafter backfilling

± 1,5

± 2,0

Parameter Unit Acceptable tolerance

Dimensions deviationfor pipe corrugation

68x13mm

Dimensions deviationfor pipe corrugation

125x26mm

Dimensions deformationafter backfilling

% of nominal equivalentdiameter

% of nominal equivalentdiameter

% of pipe span

± 2,0

± 5,0

± 2,0

Manufacturing tolerances of HelCor pipes

Manufacturing tolerances of HelCor PA pipes

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14.

8. Durability

Type of corrosion protection of HelCor and HelCor PA pipes determines

the durability of the culvert. ViaCon offers three types of corrosion

protection, which allows the long term operation of the culvert in any given

environmental condition in the most economical way.

TRENCHCOATTM and W-Protect® coating

Coating steel with a polymer film, called trenchcoating, is a technique invented, patented and used in USA since 1974

and in Europe since the beginning of 1998. The zinc coated steel strip is covered with a polymer foil in a fully controlled in-house

process. As a result a very smooth and highly adhesive layer of polymer film protects galvanized coating. Production process

conforms to EN 10169 (W-Protect®) and ASTM 742 (TrenchcoatTM). TrenchcoatTM film can be applied on either one or both sides

of the pipe. Protection obtained in such a process is the best way to prevent natural corrosion in zinc and steel, it also protects

against mechanical damage and chemical corrosion. Research findings indicate that TrenchcoatTM film resists aggressive

chemicals in excellent way. This is the best corrosion protection that is available on the culvert market today. It guarantees over

100 years life-time in most environmental conditions.

Non-aggressive environment Aggressive environment

Atmosphere aggressivenesscategory according to EN ISO 12944-2

Zinc coating 42 μm(600g/m2)

Zinc coating 70 μm(1000g/m2)

Zinc coating 42 μm (600g/m2) +polymer coating 250 μm

Water parameters

Cor

rosi

on p

rote

ctio

n en

dura

nce

Soil parameters

- C1- C2

- C3- C4- C5-I, C5-M

- pH from 6,5 to 8,0- hardness of water ≥ 20 mg Ca/I- speed of water ≤ 1,5 m/s

- pH from 6,0 to 8,0- soil permeability

k ≥ 8,0 m/24h- no organic parts- non-uniformity Cu ≥ 5 - humidity ≤ 17%

- pH from 3,0 to 6,0 & from 8,0 to 12,0

- soil permeability k < 6,0 m/h

- contains organic parts- non-uniformity Cu < 5- humidity > 17%

- pH from 3,0 to 6,5 & from 8,0 to 12,0

- hardness of water < 20 mg Ca/I- speed of water > 1,5 m/s

min. 40 years

50 - 70 years

Not recommended

20 – 50 years

over 100 years 80 to 100 years

15.

Dielectric strength of TrenchcoatTM

is 86,6 kV/mm which gives

21,6 kV for the thickness of

250 μm. This considerably out-

numbers the value of the stray

currents arising within the electri-

fied railway lines sub grade. Using

TrenchcoatTM guarantees 100%

protection against the corrosion

that may be caused by stray

currents.

* - NH4OH, H2SO4, HNO3 test at 80OC stopped due to formation of gases

** - (CH3)2CHOH, CO(CH3)2, CH3CO-O-C2H5 test at 80OC stopped due to achieve the

boiling point

Additional corrosion protection by painting

In special cases it is possible to protect the galvanized pipes with

the paint of the thickness up to 400μm. Please contact the ViaCon

technical department or your local dealer / representative.

Test

TrenchcoatTM layer chemical aggression resistance test results

Research method Outcome

Resistance to 10% concentration of HCl

Resistance to HNO3

Resistance to NH4OH

Resistance to NaOH

Resistance to 30% concentration of H2SO4

Resistance to NaOH

Resistance to 10% concentration of NaCl

Resistance to SO2 steam

Resistance to chloroform (trichlorometan CHCI3)

ASTM D1308

ASTM D1308

ASTM D1308

ASTM D1308

ASTM D543, A742

ASTM D543, A742

ASTM D543, A742

DIN 50018, 2.0L

ISO 175, 28 days, 230C

ISO 175, 28 days, 230

C

ISO 175, 28 days, 230

C

ISO 175, 28 days, 230

C

ISO 175, 90 days

ISO 175, 90 days

ISO 175, 90 days

ISO 175, 90 days

ISO 175, 90 days

ISO 175, 90 days

ISO 175, 90 days

ISO 175, 90 days

ISO 175, 90 days

ISO 175, 90 days

No decrease in coating thickness












Resistance to DMSO (dimetylosulfoxyde) (CH3)2SO

Resistance to THF (tetrahydrofuran) C4H8O

Resistance to 20% concentration of NaOHin water

Resistance to 10% concentration of ammoniaCO(NH2)2 in water

Resistance to i-propanol (CH3)2CHOH(izopropyl alkohol)

Resistance to aceton CO(CH3)2

(propanon)

Resistance to C6H5(CH3)(metylobenzen)

Resistance to poliethylen glicol C2nH4n+2On+1

Resistance to 25% concentration of NH4OH

Resistance to 25% concentration of H2SO4

Resistance to 20% concentration of HNO3

Resistance to CH3CO-O-C2H5

Resistance to MeCI2(chloro- metylene)

230C800C230C800C230C800C230C800C230C800C230C800C230C800C230C800C230C800C230C800C

No decrease in coating thickness8% decrease in coating thicknessNo decrease in coating thicknessNo decrease in coating thickness

3% decrease in coating thickness*

4% decrease in coating thickness**

3% decrease in coating thickness**

No decrease in coating thickness*No decrease in coating thickness*

No decrease in coating thickness**

No decrease in coating thickness4% decrease in coating thickness

4% decrease in coating thicknessDestruction of the coating

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Using HelCor and HelCor PA pipes enables an accurate adjustment of both ends to fit the slope and in the required angle. Bevel

cut can be done on one or both sides with full bevel or step bevel. It is recommended to use a vertical step of 1/3 the height of

the pipe.

The embankment slopes in the in- and outlet areas can be reinforced in several ways:

Vertical end pipe:

- vertical reinforced concrete head wall

- vertical wall made of gabions

Bevel end pipe:

- reinforcement of the slope with concrete or stone blocks placed

on sand-cement mix

- reinforcement with perforated concrete panels

- reinforcement with stone rip rap

- reinforcement with reinforced concrete collar

16.

9. Pipe end finishing

It is possible for both skewed inlet/outlet of the culvert (at the culvert

and road axis intersection angle ≠ 90°) to be square beveled.

Minimum allowable skew angle is 55°.

In special cases it is necessary to make additional reinforcements

in the skewed area.

17.www.viacon.pl

18.

10. Fittings

Depending on the function of the structure, HelCor and HelCor PApipes can be equipped with additional elements, e.g.

fittings

connection pipes

grids

latches, walls throttles, etc.

elbows, three-way adapters, flanges

manholes, pumping stations equipment

steel shelves for animals

19.

11. Cover depth

Culvert cover under road can be described as a vertical distance between the top of the culvert and the road grade-line,

including the road pavement construction.

Culvert cover under railway can be described as a vertical distance between the top of the culvert and the bottom of the railway

sleeper, including the construction layers of the railroad.

Below formulas can be used for calculation of the depth of cover for the A-class road live load or the k+2 class railway live load

(UIC-71), respectively to the Polish Bridge Standard PN-85/S-10030, providing that the standard thickness of the pipe wall is

applied (as described in chapter 6). If other live load is expected, plate thickness should be matched with respective standard

requirements.

For road applications, the minimum allowable depth of cover is the largest of:

H=B/6 [m], H=B/8+0,2 [m], H≥0,6 m

For the railway applications, the minimum allowable depth of cover is the largest of:

H=B/4 [m], H≥0,6 mwhere:

H – depth of cover [m]

B – diameter or span of a pipe [m]

When the thickness of road surface structure

is greater then minimum cover, the aggre-

gate thickness over the structure should be

at least 0,10 – 0,15 m, measured from the top

of the pipe.

For the road culverts in special conditions,

e.g. exits from main roads, the minimum

depth of cover can be 0,3m. In a case when

it is necessary to build a culvert with a lower cover or with a non-standard thickness of the steel, a static calculations should

be performed.

When technological traffic should run over the culvert on a job site, special features should apply. The minimum cover must

be adjusted to extreme construction. It can be performed as placing concrete slabs over the culvert or adding another layer

of compacted soil. Stopping of the construction equipment directly over or directly next to a culvert is not allowed.

For more details or other solutions please contact the ViaCon technical department or your local dealer / representative.

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20.

12. Bedding and backfilling

Requirements for bedding preparation:

- bedding should extend transversely to at least half of pipe’s diameter or span, and not less than 0,60m on each side of the culvert

- thickness of bedding should not be smaller than 20cm (30cm recommended)

- aggregate degree of compaction should not be smaller than Is=0,98 according to standard Proctor density

- extra layer with 5cm of loose sand material should be made on the bedding so that the pipe corrugation can be seated on the

bedding.

HelCor and HelCor PA pipes tolerates uneven settlements of the subsoil very well. They can be successfully used on soft soils

and subsidence areas. It is related to distribution of pressure around the pipes which in contrary to concrete pipes, limits the

downward pressure directly under pipe.

In order to ensure correct work of flexible pipe several conditions must be fulfilled, i.e. concerning bedding preparation, making of

aggregate foundation as well as proper backfilling of the structure. Appropriate performance of structure and its durability depends

on quality of these steps. The designer should specify the load bearing capacity of the subsoil on which HelCor pipe should be

placed. Subsoil which does not meet the demands should be reinforced with use of geotextile or other common geotechnical

means.

Graining of the bedding and backfilling material (gravel, coarse, gravel-sand mixture) depends on the corrugation type. Maximum

size of grain in the vicinity ( 0,3m - 0,5m) of HelCor and HelCor PA is 31,5mm. For remaining zone bigger grains can be used.

Material for bedding and backfill should meet the following demands:

non-uniformity index

curvature index

permeability

Cu>5,0

1<Cc<3

U>6 m/24 hours

21.

Requirements for backfill preparation:

- backfill adjacent to pipe should exceed its perimeter by half its diameter or

span and not less than 0,60m on each side of the pipe (for installation in

trench minimum is 0,30m).

- backfill should be evenly laid in not compacted layers at maximum 30cm

thick, on each side of the pipe, no more than one layer difference

in elevation on each side of the pipe should be allowed

- degree compaction of each layer should not be less than Is=0,98

standard Proctor density, however, directly near the pipe, Is=0,95 is

allowed

Backfill compaction should be carried out using light backfilling equipment

(vibrating plates or jumping jacks). Heavy backfilling equipment is not

allowed until the full backfill height has been laid. Appropriate compaction in

haunch area of the pipe is very important due to load bearing capacity

of a culvert.

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22.

13. Structural design

Each application of HelCor and HelCor PA pipes requires a technical design, including

estimated loads, hydrological conditions or clearance to choose the appropriate diameter or

dimensions of the pipe. Life-time analysis should specify corrosion protection to be applied.

The design should follow the guidelines issued by ViaCon and local requirements.

HelCor and HelCor PA culverts are produced according to the technical design in its final

form, i.e. length, bevel, skew. All cutting, welding, corrosion protection and coupling bands

are performed by the producer in the factory.

Designing guideline

- selection of pipe diameter or dimensions depending on the function

of a structure (hydraulics, clearance, etc.)

- setting bottom-line of the culvert (proper grade should be designed to

prevent erosion under the pipe)

- checking minimum cover condition for expected live load

- specifying corrosion protection required durability

- specifying thickness of steel wall and corrugation type

- bedding (foundation) and backfill designing

- calculation of culvert length

- selection of pipe end finish type (inlet and outlet)

- other features design

23.

Relining

HelCor and HelCor PA can be used for relining purposes. Prior to relining a good

check of internal dimensions of existing culverts or bridges that will be relined is

required. Also, the bedding conditions need to be investigated. Space in between

existing structures and HelCor or HelCor PA should be filled with concrete

semi-liquid or liquid mixture pressurised in order to fill in the space completely.

A minimum of 10 cm space is recommended (15cm strongly recommended). Load

bearing capacity of the concrete filling the gap is neglected in the static

calculations. The culvert should be secured from any movement when filling the

gap with concrete . Ballasting with sandbags and staged pouring with concrete is

recommended. For HelCor arches determination of placing them on foundations

should be done.

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14. Installation and construction procedures

Soil-structure interaction is a main concept when building flexible culverts. Appropriate assembly in accordance with

the producers guidelines, as well as appropriate backfilling procedures are the key factors in successful installations.

24.

Pipes are delivered to the job site by trucks. Unloading and placing of the pipes should be performed with a use of light

mechanical devices (crane or pay-loaders) with the help of textile belts. Pipes should not be dumped from the truck.

Pipes are connected with coupling-bands. Separate elements (pipes and

coupling-bands) are marked by the producer in a way allowing for fast and cor-

rect assembly.

The process of assembling HelCor and HelCor PA pipes is not complicated

and can be performed by a group of unskilled workers under the supervision

of an engineer. It allows for a quick work, without the use of heavy or specia-

lized mechanical equipment, even in bad weather conditions. Short construc-

tion time reduces the inconvenience in traffic related to blocking of a road, and

the relining allows for carrying out the construction work without stopping the

traffic and dismantling the old structure.

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15. Other applications

HelCor and HelCor PA can be used when building orre-building of the following

26.

underground retention tanks

lightening of concrete decks in bridges

manholes, pump stations,

27.

under- and on-ground ventilation systems

technological tunnels, escape routes, conveyor protection

For further questions, please contact ViaCon technicaldepartment or local dealer or representative.

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ViaCon Sp. z o.o.

ViaCon Sp. z o.o. is a member of ViaCon Group established in Sweden and Norway in 1986. At present ViaCon Group operates in a dozen or so European countries and belongs to SAFEROAD® Group. Thanks to the support from the entire group and the possibility of using the shared experience, each member company can offer professional technical consulting and top quality products.

Business profile of the company:

• manufacture, design, sale and installation of plastic and steel pipes and flexible structures used for construction and repair of culverts, bridges, overpasses, tunnels, farm accommodation underpasses, wildlife crossings, other engineering structures, and used also as belt conveyor housings,

• manufacture, design and sale of storm water drainage systems and holding tanks,

• design, sale and installation of geosynthetics, such as non-woven geotextile fabrics, woven geotextile fabrics, geogrids, geomembranes, and bentonite mats,

• sale and lease of temporary bridges,• sale of gabions,• design, manufacture and sale of three

retaining structure systems from reinforced soil.

Woven and non-woven geotextiles

HelCor® MultiPlate MP200HelCor PA®PECOR OPTIMA®

Gabions

Acrow® 700XS® - temporary bridges

HelCor® wells

PECOR OPTIMA® M wells

SuperCor® Geogrids

HelCor® TC holding tanks Pecor Quattro sewage system

ViaWall B retaining walls ViaBlock retaining wallsViaWall A retaining walls

MP200 pl ok_folder-srodek2.qxd 2012-10-08 15:00 Strona 13

ViaCon Sp. z o.o. ul. Przemysłowa 6 64-130 Rydzyna, Polandphone: +48 65 525 45 45fax: +48 65 525 45 55e-mail: [email protected]

Our goal is to improve products and to cooperate closely with customers, scientific and research centres, public administration and suppliers.

That’s why our motto is:

”Let’s Create a Better Future Together”

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