6
MODERN SEWER DESIGN
Fabricated fittings can be made to solve almost any sewer problem.
7
CHAPTER 1
Steel Sewer Products
Introduction
Corrugated steel pipe (CSP) provides a strong, durable, economical selection for the construction of sewer systems. Introduced by a city engineer in
1896, countless miles of CSP now provide reliable service throughout the
highway system, and in large and small municipalities across the North
American continent.
The sewer designer can select from a wide range of CSP products to
meet exacting job requirements. Factory made pipe, in sizes large enough
to accommodate most needs is available with a variety of corrugation profiles that provide optimal strength. For larger structures, structural plate
pipe can be furnished for bolted assembly in the field. Shop fabricated
fittings; long lightweight sections; reliable and positive coupling systems—
all contribute to speed and economy in field installation. In addition, a
range of protective coatings is available to meet rigorous service demands.
CORRUGATED STEEL PIPE AND STRUCTURAL PLATE PIPE DATA
CORRUGATED STEEL PIPE
There are basically two types of corrugated steel pipe: helical and annular.
Helical CSP, where the corrugations and seams run helically around the
pipe is fabricated by:
a) lockseam method,
b) continuous welding of the seams,
c) integrally attaching at the lockseam a helically corrugated steel sheet
with a smooth inner steel lining (smooth lined pipe).
Reformed annular ends for joining are available.
Annular CSP, where the corrugations run annularly around the pipe is
fabricated by:
a) riveting the seams,
b) bolting the seams,
c) resistance spot welding the seams.
A wide variety of geometrical shapes are available in corrugated steel
pipe to satisfy requirements such as low headroom or greater hydraulic
efficiency. See Tables 1.7, 1.8, 1.9, 1.10 and 1.11.
Table 1.1 illustrates the sizes, corrugation profiles, steel thickness and
shapes available for the various types of steel pipe.
Handling weights for CSP are shown in Tables 1.2, 1.3, 1.4, 1.5 and 1.6.
Tables 1.7 and 1.8 show the design details for corrugated steel pipe-arches.
STRUCTURAL PLATE PIPE
For larger structures requiring field assembly, structural plate pipe is available. Structural plate pipe is fabricated from hot-dip galvanized plates and
is assembled by bolting individual plates together to form large pipes, pipearches and a variety of other shapes.
Standard sizes of structural plate are indicated in Table 1.1.
Sizes and layout details for circular pipe, pipe-arches and arches are
illustrated in Tables 1.9, 1.10 and 1.11.
8
MODERN SEWER DESIGN
Round
Pipe Arch
Table 1.1
Sizes, corrugation profiles, thickness and shapes available for various types of
steel pipe
Size
(Diameter or
Span)
Corrugation
Profile
Specified
Thickness
Range
Shape
Corrugated
Steel Pipe
(Helical and
Annular Pipe)
150 - 250
300 - 2400
1200 - 3600
1200 - 3600
450 - 2130
1330 - 2010
1330 - 2010
38 x 6.5
68 x 13
76 x 25
125 x 26*
68 x 13
76 x 25
125 x 26
1.3 - 1.6
1.3 - 4.2
1.6 - 4.2
1.6 - 4.2
1.6 - 4.2
1.6 - 4.2
1.6 - 3.5
Round
Round
Round
Round
Pipe Arch
Pipe Arch
Pipe Arch
Spiral Rib Pipe
450 - 2600
19 x 19 rib at 190
1.6 - 2.8
Round
Structural
Plate Pipe
1500 thru
8020 and larger
152 x 51
3.0 - 7.0
Round, Pipe Arch
Elliptical, Arch and
Other Special Shapes
Type of Pipe
*Available only in helical pipe. Note: All dimensions are in millimetres.
Table 1.2
Corrugated Steel Pipe (CSP) - round standard diameters, end areas, and handling
weights (38 mm x 6.5 mm)
Estimated average weights - not for specification use
Approximate Kilograms per Linear Metre
(Weights will vary slightly with fabrication method)
Inside
Diameter
(mm)
End
Area
(m2)
Specified
Thickness
(mm)
Metallic
Coated*
Full Bituminous
Coated
150
0.018
1.3
1.6
5.9
7.2
7.2
8.5
200
0.031
1.3
1.6
7.7
9.5
9.4
11.0
250
0.049
1.3
1.6
9.6
12.0
12.0
14.0
Note: perforated sub-drains will weigh slightly less
*Metallic coated: Galvanized or Aluminum Type 2
1. STEEL SEWER PRODUCTS
9
Table 1.3
Corrugated Steel Pipe (CSP) - round standard diameters, end areas, and handling
weights (68 mm x 13 mm)
Estimated average weights - not for specification use*
Approximate Kilograms Per Linear Metre**
Inside
Diameter
(mm)
End
Area
(m2)
Specified
Thickness
(mm)
300
0.07
400
0.13
500
0.2
600
0.28
700
0.38
800
0.5
900
0.64
1000
0.79
1200
1.13
1400
1.54
1600
2.01
1800
2.54
2000
3.14
2200
3.8
2400
4.52
1.3
1.6
2.0
1.3
1.6
2.0
1.3
1.6
2.0
2.8
1.3
1.6
2.0
2.8
1.6
2.0
2.8
1.6
2.0
2.8
1.6
2.0
2.8
3.5
4.2
1.6
2.0
2.8
3.5
4.2
1.6
2.0
2.8
3.5
4.2
2.0
2.8
3.5
4.2
2.0
2.8
3.5
4.2
2.8
3.5
4.2
2.8
3.5
4.2
3.5
4.2
4.2
Metallic
Coated
12
14
18
16
19
24
19
24
30
41
23
28
35
49
33
41
57
37
47
65
42
53
73
90
108
47
58
81
100
120
56
70
97
120
144
81
113
140
168
93
130
160
192
146
179
215
162
199
239
219
263
287
Full
Bituminous
Coated
Full
Bituminous
Coated and
Invert Paved
Full
Bituminous
Coated and
Full Paved
15
17
21
20
23
28
24
29
35
46
28
33
40
54
39
47
63
44
54
72
50
61
81
98
116
56
67
90
109
129
66
80
107
130
154
93
125
152
180
107
144
174
206
162
195
231
179
216
256
238
282
308
17
19
23
22
25
30
27
32
38
49
32
37
44
58
44
52
68
49
59
77
56
67
87
104
122
62
73
96
115
135
74
88
115
138
162
102
134
161
189
117
154
184
216
174
206
242
192
229
269
252
296
323
22
24
28
30
33
38
36
41
47
58
44
49
56
70
57
65
81
64
74
92
73
84
104
121
139
81
92
115
134
154
97
111
138
161
185
129
161
188
216
148
185
215
247
208
241
277
230
267
307
294
338
369
*Lock seam construction only; weights will vary with other fabrication practices
**For other coatings or linings the weights may be interpolated
Note: Pipe arch weights will be the same as the equivalent round pipe
For example, for 1030 mm x 740 mm, 68 mm x 13 mm in Pipe Arch,
refer to 800 mm diameter pipe weight
10
MODERN SEWER DESIGN
Table 1.4
Corrugated Steel Pipe (CSP) - round standard diameters, end areas, and handling
weights (76 mm x 25 mm)
Estimated average weights - not for specification use*
Approximate Kilograms Per Linear Metre**
Inside
Diameter
(mm)
End
Area
(m2)
1200
1.13
1400
1.54
1600
2.01
1800
2.54
2000
3.14
2200
3.8
2400
4.52
2700
5.73
3000
7.07
3300
8.55
3600
10.18
Specified
Thickness
(mm)
1.6
2.0
2.8
1.6
2.0
2.8
3.5
1.6
2.0
2.8
3.5
4.2
1.6
2.0
2.8
3.5
4.2
1.6
2.0
2.8
3.5
4.2
1.6
2.0
2.8
3.5
4.2
1.6
2.0
2.8
3.5
4.2
1.6
2.0
2.8
3.5
4.2
2.0
2.8
3.5
4.2
2.8
3.5
4.2
3.5
4.2
Metallic
Coated
65
81
112
75
94
131
161
86
107
149
184
221
96
120
167
206
248
107
133
186
229
275
117
147
204
252
302
128
160
221
274
329
144
179
250
308
370
199
278
342
411
305
376
451
410
492
Full
Full
Bituminous
Bituminous Coated and
Coated
Invert Paved
77
93
124
89
108
145
175
102
123
165
200
237
114
138
185
224
266
127
153
206
249
295
139
169
226
274
324
152
184
245
298
353
171
206
277
335
397
229
308
372
441
338
409
484
446
528
*Lock seam construction only; weights will vary with other fabrication practices
**For other coatings or linings the weights may be interpolated
Note: Pipe arch weights will be the same as the equivalent round pipe
For example, for 1550 mm x 1200 mm, 76 mm x 25 mm in Pipe Arch,
refer to 1400 mm diameter pipe weight
90
106
137
104
124
160
190
120
141
183
218
255
134
158
205
244
286
149
175
228
271
317
163
193
250
298
348
178
210
272
324
380
201
236
307
365
427
262
341
405
474
374
445
520
486
568
Full
Bituminous
Coated and
Full Paved
130
146
177
151
170
207
237
173
194
236
271
308
194
218
264
304
346
215
241
294
337
383
236
266
323
371
421
258
290
351
404
459
290
325
396
454
516
362
440
504
574
484
555
630
605
687
1. STEEL SEWER PRODUCTS
11
Table 1.5
Corrugated Steel Pipe (CSP) - round standard diameters, end areas, and handling
weights ( 125 mm x 26 mm)
Estimated average weights - not for specification use*
Approximate Kilograms Per Linear Metre**
Inside
Diameter
(mm)
End
Area
(m2)
1200
1.13
1400
1.54
1600
2.01
1800
2.54
2000
3.14
2200
3.8
2400
4.52
2700
5.73
3000
7.07
3300
8.55
3600
10.18
Specified
Thickness
(mm)
1.6
2.0
2.8
1.6
2.0
2.8
3.5
1.6
2.0
2.8
3.5
4.2
1.6
2.0
2.8
3.5
4.2
1.6
2.0
2.8
3.5
4.2
1.6
2.0
2.8
3.5
4.2
1.6
2.0
2.8
3.5
4.2
1.6
2.0
2.8
3.5
4.2
2.0
2.8
3.5
4.2
2.8
3.5
4.2
3.5
4.2
Metallic
Coated
57
71
100
66
83
116
144
76
95
132
165
197
85
106
148
185
221
94
118
165
205
245
104
129
181
225
269
113
141
197
245
293
127
159
222
276
330
176
246
306
366
270
336
402
367
438
Full
Full
Bituminous
Bituminous Coated and
Coated
Invert Paved
68
82
111
79
96
129
157
90
109
147
179
211
101
122
165
201
237
112
136
183
223
263
123
149
201
246
289
135
163
219
267
316
151
183
246
300
354
203
273
333
393
300
366
432
389
470
82
96
124
95
112
145
173
108
127
165
198
230
122
143
185
222
258
136
159
206
246
286
149
175
226
270
314
162
190
247
295
343
183
214
277
331
385
238
307
368
428
338
404
470
440
511
Full
Bituminous
Coated and
Full Paved
123
137
166
143
160
193
221
163
182
220
252
284
184
205
247
284
320
204
228
274
315
355
224
250
302
346
390
245
273
329
377
425
275
307
370
424
478
340
410
470
530
451
517
583
564
635
*Lock seam construction only; weights will vary with other fabrication practices
**For other coatings or linings the weights may be interpolated
Note: Pipe arch weights will be the same as the equivalent round pipe
PERFORATED PIPE
Corrugated steel pipe is available with perforations for collection or dissemination of water underground. Most fabricators are equipped to furnish
10 mm round holes. Other sizes and configurations are available.
The most common standard pattern is 320 - 10 mm round holes per square
metre of pipe surface. See Chapter 6 for design requirements.
12
MODERN SEWER DESIGN
Table 1.6
End areas and handling weights of spiral rib pipe
(19 mm x 19 mm rib at 190 mm)
Estimated average weights - not for specification use*
Approximate Kilograms Per Linear Metre**
Inside
Diameter
(mm)
End
Area
(m2)
Specified
Thickness
(mm)
Metallic
Coated
Full
Bituminous
Coated
Full
Bituminous Coated
and Invert Paved
450
0.16
1.6
2.0
22
27
28
33
30
34
525
0.22
1.6
2.0
2.8
25
31
43
31
37
49
33
39
49
600
0.28
1.6
2.0
2.8
30
36
54
37
43
61
39
44
63
750
0.44
1.6
2.0
2.8
37
46
63
46
55
71
49
58
74
900
0.64
1.6
2.0
2.8
45
55
74
55
65
85
58
68
88
1050
0.87
1.6
2.0
2.8
52
64
86
64
76
98
67
79
101
1200
1.13
1.6
2.0
2.8
60
73
100
74
88
115
77
91
118
1350
1.43
1.6
2.0
2.8
67
82
112
83
98
128
86
101
131
1500
1.77
1.6
2.0
2.8
74
91
124
92
109
141
95
112
144
1650
2.14
2.0
2.8
100
137
119
156
122
159
1800
2.54
2.0
2.8
109
149
129
170
134
174
2100
3.46
2.0
2.8
106
173
131
198
135
202
2400
4.52
2.8
198
228
234
2600
5.31
2.8
210
243
249
*Lock seam construction only
**For other coatings or linings the weights may be interpolated
Rise
13
R
t
R
b
1. STEEL SEWER PRODUCTS
R
c
Rc
B
Span
Table 1.7
Sizes and layout details - CSP pipe arches
(68 mm x 13 mm corrugation)
Waterway
Area
Layout Dimensions
Equiv.
Diameter
(mm)
Span
(mm)
Rise
(mm)
(m2)
B
(mm)
Rc
(mm)
Rt
(mm)
Rb
(mm)
400
500
600
700
800
900
1000
1200
1400
1600
1800
450
560
680
800
910
1030
1150
1390
1630
1880
2130
340
420
500
580
660
740
820
970
1120
1260
1400
0.11
0.19
0.27
0.37
0.48
0.61
0.74
1.06
1.44
1.87
2.36
130
165
190
220
255
285
310
375
430
500
560
110
135
165
190
220
245
270
325
380
435
495
225
285
340
400
460
525
585
715
845
990
1140
440
555
740
900
1040
1190
1405
1730
2205
2510
2955
Dimensions shown are not for specification purposes, subject to manufacturing tolerances
Table 1.8
Sizes and layout details - CSP pipe arches
(125 mm x 25 mm and 76 mm x 25 mm corrugation)
Waterway
Area
Layout Dimensions
Equiv.
Diameter
(mm)
Span
(mm)
Rise
(mm)
(m2)
Rc
(mm)
800
1000
1200
1400
1600
1800
2000
2200
2400
2700
3000
3300
3600
1000
1100
1330
1550
1780
2010
2230
2500
2800
3300
3650
3890
4370
700
850
1030
1200
1360
1530
1700
1830
1950
2080
2280
2690
2870
0.61
0.74
1.09
1.48
1.93
2.44
2.97
3.44
4.27
5.39
6.60
8.29
9.76
150
150
175
175
250
300
400
400
400
400
400
450
450
Dimensions shown are not for specification purposes, subject to manufacturing tolerances
14
MODERN SEWER DESIGN
Table 1.9
Size and layout details - structural plate circular pipe
(152 mm x 51 mm corrugation profile)
Inside
Diameter (mm)
Waterway Area
(m2)
1500
1660
1810
1970
2120
2280
2430
2590
2740
3050
3360
3670
3990
4300
4610
4920
5230
5540
5850
6160
6470
6780
7090
7400
7710
8020
1.77
2.16
2.58
3.04
3.54
4.07
4.65
5.26
5.91
7.32
8.89
10.61
12.47
14.49
16.66
18.99
21.46
24.08
26.86
29.79
32.87
36.10
39.48
43.01
46.70
50.53
Periphery Total
N
20
22
24
26
28
30
32
34
36
40
44
48
52
56
60
64
68
72
76
80
84
88
92
96
100
104
Rise
15
R
t
R
b
1. STEEL SEWER PRODUCTS
R
c
Rc
B
Span
Table 1.10
Sizes and layout details - structural plate pipe-arches
(152 mm x 51 mm corrugation profile)
Dimensions
Span
(mm)
Rise
(mm)
2060
2240
2440
2590
2690
3100
3400
3730
3890
4370
4720
5050
5490
5890
6250
7040
7620
1520
1630
1750
1880
2080
1980
2010
2290
2690
2870
3070
3330
3530
3710
3910
4060
4240
Waterway
Area
Layout Dimensions
(m2)
B
(mm)
Rt
(mm)
Rb
(mm)
Rc
(mm)
Periphery
Total
N
2.49
2.90
3.36
3.87
4.49
4.83
5.28
6.61
8.29
9.76
11.38
13.24
15.10
17.07
19.18
22.48
25.27
700
680
730
735
815
790
840
900
915
1035
1015
1040
1095
1150
1120
1660
1750
1130
1205
1305
1355
1380
1695
2000
2055
1975
2265
2425
2570
2790
3020
3175
4090
4570
1875
3370
2995
4420
4050
3850
3510
4045
6015
4895
6430
7430
7575
7755
9630
9650
9650
660
660
685
710
785
685
660
710
815
815
815
840
840
840
840
1370
1370
24
26
28
30
32
34
36
40
44
48
52
56
60
64
68
74
79
Dimensions are to inside crests and are subject to manufacturing tolerances. N = 3 Pi = 244 mm
16
Rise
Rise
MODERN SEWER DESIGN
Span
Table 1.11 Representative sizes of structural plate arches
Inside Dimensions*
Span
(mm)
Rise
(mm)
End
Area**
(m2)
Rise
over
Span
Radius
(mm)
Periphery
(Hole Spaces)
N
1520
1830
810
840
970
860
1120
1020
1270
1180
1440
1350
1600
1360
1750
1520
1910
1680
2060
1840
2210
1870
2360
2030
2520
2180
2690
2210
2720
2360
2880
2530
3050
0.98
1.16
1.39
1.39
1.86
1.86
2.42
2.46
3.07
3.16
3.81
3.44
4.65
4.18
5.48
5.02
6.50
5.95
7.43
6.41
8.55
7.43
9.75
8.55
11.06
9.01
11.71
10.22
13.01
11.52
14.59
0.53
0.46
0.53
0.40
0.53
0.42
0.52
0.43
0.53
0.44
0.52
0.41
0.52
0.42
0.52
0.42
0.52
0.43
0.52
0.41
0.52
0.42
0.52
0.42
0.52
0.40
0.50
0.41
0.50
0.41
0.50
760
930
910
1090
1070
1230
1220
1400
1370
1540
1520
1710
1680
1850
1830
2010
1980
2160
2130
2340
2290
2480
2440
2620
2590
2820
2740
2950
2900
3100
3050
10
11
12
12
14
14
16
16
18
18
20
19
22
21
24
23
26
25
28
26
30
28
32
30
34
31
35
33
37
35
39
2130
2440
2740
3050
3350
3660
3960
4270
4570
4880
5180
5490
5790
6100
*Dimensions are to inside crests and are subject to manufacturing tolerances
**End area under soffit above spring line
1. STEEL SEWER PRODUCTS
17
ARCH CHANNELS
For arch seats, galvanized unbalanced channels with anchor lugs are available. See Figure 1.1 below.
Cross Section
Slotted
Holes
3050 or 3660 mm Unbalanced Channel
75 mm
50 mm
Anchor Lugs
Bent Down and
Twisted in Field
Elevation
Figure 1.1 General dimensions of unbalanced channels for structural plate arches
CSP COUPLING SYSTEMS
A wide variety of pipe joints are available for field connecting lengths of
corrugated steel pipe. The following drawings illustrate and define the standard joints which are tabulated in Table 1.12.
Band
CSP FIELD JOINTS
Type - Band Coupling
Pipe 1
Typical Band Coupling
Pipe 2
1. The most common CSP joint uses a band
around the pipe joint.
2. The band is drawn and secured on the pipe by
connection devices.
3. The pipe ends may be identical to the rest of the pipe barrel (plain ends), or in the case of
helical pipe, the pipe ends may be reformed to an annular corrugation or flange
(reformed ends).
4. Gaskets of three types are used according to band type; o-ring, sleeve type or mastic.
Table 1.12 Coupling bands for corrugated steel pipe
Gaskets
Type Of
Band
Pipe End
Bar,
Sleeve
Helical
XBolt Wedge O
or
Annular
Section Angles & Strap Lock Ring Strip Mastic Plain Plain Reformed
Universal
Dimple
X
X
X
X
X
X
X
X
Corrugated
X
X
X
X
X
X
X
X
Hugger
X
X
X
X
X
X
Flat
X
X
X
X
X
X
X
X
X
X
18
MODERN SEWER DESIGN
Reformed Pipe End
Standard CSP Band Types
O-Ring
Corrugated
Hugger Type
Sleeve Gasket
for Helical
Sleeve Gasket
O-Ring
for Annular
Flat Type
When gaskets are required, they are placed as shown.
Sleeve Gasket
Universal Type
1. STEEL SEWER PRODUCTS
19
Standard CSP Gaskets
O-Ring Gasket
Sleeve Gasket
Strip Gasket
Standard CSP Band Connectors
Band Angle Connector
Bar & Strap Connector
Wedge Lock Connector
20
MODERN SEWER DESIGN
CSP FIELD JOINTS (Cont’d)
For unusual conditions, (i.e. high pressures, extreme disjointing forces,
threading pipe inside existing pipe, jacking or boring pipe, and deep vertical drop inlets) a variety of special designs are available or a new special
joint may be designed by the manufacturer to meet a new requirement.
Rod & Lug
Band is secured
by rod around band
connected by lugs
Flange Joint
Bolted flanges
are attached to
pipe ends
Open Lap Joint
Used in stab type
joints for boring and
jacking pipe. May be
bolted if required.
Internal Type
1. STEEL SEWER PRODUCTS
21
CSP FITTINGS AND SEWER APPURTENANCES
An important feature of corrugated steel pipe sewers is the wide range of
fittings and appurtenances which can be employed. The nature of the material makes possible almost any special fitting which can be designed. When
possible it is generally most economical to use the most commonly produced or “standard” fittings. To guide the designer, presented herein are
the typical fittings and appurtenances fabricated throughout the country.
Sewer system hardware such as grates, manhole covers, ladders and steps
are easily incorporated in corrugated steel manholes or inlets. The following pages illustrate how this hardware is used in corrugated steel structures.
FITTINGS
Tables l.l3, 1.14, and 1.15, list the standard, or minimum dimensions of
common fittings and elbows. Note that these are minimum dimensions. It
may be most practical in some cases to fabricate fittings with longer legs
than those shown here. It is ordinarily best to let the contractor and supplier work out such details. However, it may be useful for the designer to
have these minimum dimensions in laying out turns or intersections where
precision is required.
Pipe sizes larger than those shown in these tables should be individually
designed. The larger sizes can require longer leg dimensions depending on
wall thickness and type of pipe fabrication.
Common manifold eliminates costly junction box used with other storm
drain materials.
22
MODERN SEWER DESIGN
Table 1.13 Minimum dimensions for elbows for round CSP (mm) all corrugations
A
A
A
B
A
A
A
2 Piece
2 Piece
3 Piece
L
L
L
10° - 45° Elbow
46° - 90° Elbow
46° - 90° Elbow
Pipe
Diameter
A
Total
Length
Pipe
Diameter
A
Total
Pipe
Length Diameter
150 - 600
700 - 1400
1600 - 2400
300
600
900
600
1200
1800
150 - 250
300 - 800
900 - 1200
300
600
900
600
1200
1800
1400 - 1600 1200
1800 - 2400 1500
2400
3000
Total
Length
A
B
150
200
250
200
185
175
200
230
250
600
600
600
300
400
460
450
280
300
1200
1200
500
600
700
800
900
1000
1200
1400
1600
1800
2000
2200
2400
425
410
400
360
600
610
570
750
780
750
1000
950
925
350
380
400
480
600
580
660
900
840
900
1000
1100
1150
1200
1200
1200
1200
1800
1800
1800
2400
2400
2400
3000
3000
3000
NOTE: The total length (mm) and pipe diameter (mm) listed are minimum requirements for fitting
fabrication. Fittings with other dimensions to satisfy specific needs are also available. All dimensions are
nominal. All dimensions are in millimetres.
1. STEEL SEWER PRODUCTS
23
Table 1.14 Minimum dimensions for CSP round fittings (mm)
B
B
A
A
A
C
A
B
45° Wye
Stub Same or Smaller Than Main Diameter
Main
Diam.
(mm)
45° Lateral
Cross
Tee
A
A
B
Tee
A
150 600
200 600
250 600
300 800
400 1200
500 1200
B
Cross
TL
A
B
Same Diam.
45° Lateral
TL
A
300 900 600
300 900 600
300 900 600
400 1200 1200
600 1800 1200
600 1800 1200
300
300
300
600
600
600
1200 900
1200 900
1200 900
2400 1200
2400 1200
2400 1500
45° Wye
B
C
TL
A
TL
600
600
600
600
900
900
300
300
300
400
400
450
1500
1500
1500
1800
2100
2400
300 900
300 900
300 900
600 1800
600 1800
600 1800
600
700
800
900
1000
1200
1200
1200
1800
1800
1800
1800
600
600
900
900
900
900
1800
1800
2700
2700
2700
2700
1200
1200
1800
1800
1800
1800
600
600
900
900
900
900
2400
2400
3600
3600
3600
3600
1500
1800
2400
2400
2400
3000
900
1200
1500
1500
1500
1800
500
600
660
660
760
810
2400
3000
3900
3900
3900
4800
600
600
900
900
900
900
1800
1800
2700
2700
2700
2700
1400
1600
1800
2000
2200
2400
2400
2400
3000
3000
3000
3000
1200
1200
1500
1500
1800
1800
3600
3600
4500
4500
4500
5400
2400
2400
3000
3000
3000
3600
1200
1200
1500
1500
1500
1800
4800
4800
6000
6000
6000
7200
3600
3600
4200
4800
4800
4800
2100
2400
2700
3000
3300
3300
1100
1200
1250
1400
1500
1550
5700
6000
6900
7800
8100
8100
1200
1200
1500
1500
1500
1800
3600
3600
4500
4500
4500
5400
TL - total net length needed to fabricate fitting
Note: All dimensions are in millimetres
24
MODERN SEWER DESIGN
Table 1.15 Minimum dimensions for CSP pipe arch elbow fittings
Rise
Span
A
A
A
A
S
S
A
S
A
2 Piece
2 Piece
S
3 Piece
S
S
L
L
L
10° - 45° Elbow
50° - 90° Elbow
90° Elbow
Equivalent
Round
Diameter
Span
S
Rise
R
(mm)
(mm)
(mm)
A(mm)
L(mm)
A(mm)
L(mm)
A(mm)
L(mm)
500
600
700
800
900
1000
1200
1400
1600
1800
560
680
800
910
1030
1150
1390
1630
1880
2130
420
500
580
660
740
820
970
1120
1260
1400
500
450
400
400
700
650
600
850
850
1050
1200
1200
1200
1200
1850
1850
1850
2450
2450
3050
650
850
800
750
950
900
1100
1300
1500
1400
1850
2450
2450
2450
3050
3050
3650
4250
4900
5500
750
700
800
950
900
1150
1050
1300
1550
1800
1850
1850
2000
2450
2450
3050
3050
3660
4250
4900
Dimensions - nominal
45° Elbow
2 Piece
90° Elbow
2 Piece
90° Elbow
3 Piece
L - length for fabrication
1. STEEL SEWER PRODUCTS
25
SADDLE BRANCH
Saddle branches are used to connect smaller branch lines to the main. Saddles make it practical to accurately tie in connections after the main line is
laid. Or, new connections can be effectively made on old lines with saddles. Saddles can be used to connect almost any type of pipe to a CSP
main. A common “universal” type of saddle branch stub to do this is shown
below.
Connecting Pipe
Fill Annular Space
With Mastic Sealant
Saddle
Plate
Oversize CSP Stub
Universal Connection Detail Using Saddle Branch
Typical pre-fabricated CSP saddle branch fitting used in connecting house laterals or
incoming pipe from catch basins.
A
Saddle Plate
Shop Weld
Section A-A
A
Side View of Sewer with Saddle Branch in Place
Figure 1.2 Saddle branch, bolted to main sewer on the job or at the plant, enables
laterals and house connections to join the sewer
26
MODERN SEWER DESIGN
TRANSITIONS
Changes in pipe diameter should be accomplished in junction structures.
However, there are circumstances when a pipe reducer or enlarger section
is desired.
A simple, instant size change can be done as shown in Figure 1.3.
Tapered transitions may be fabricated in smooth steel for helical pipe
systems as shown in Figure 1.4. Reinforcement may be required.
Plate
Flow
Smooth Taper Section
Figure 1.3 Enlarger
Flow
Figure 1.4 Eccentric Transition
Saddle branch manhole is bolted to sewer conduit while riser extension is being
lowered and coupled.
1. STEEL SEWER PRODUCTS
27
MANHOLES AND CATCH BASINS
Trunk Line
Riser Type Manhole
Vertical Shaft Type Manhole
Welded Flange for Cover
or Grade Ring
Smooth Steel
Eccentric Reducer
Larger Diameter
CSP Manhole Junction
Reduction Details
Manholes are available in corrugated pipe construction in two basic types
as shown above. The riser type of manhole is the simpler of the two and
quite economical. It is only feasible for trunk lines of 900mm diameter or
greater. When junctions of smaller diameters are involved it is possible to
use a vertical shaft of larger diameter CSP to connect the sewers. However, when the shaft is greater than 900mm in diameter, some reduction
detail must be used to suit the cover. Typical reduction details are shown.
28
MODERN SEWER DESIGN
MANHOLE AND CATCH BASIN TOPS
Manhole Cover
or Grate
Concrete Top
Poured in Place
or Pre-Cast
Manhole Cover
or Grate
1
Flat Steel Plate Cover
Three Lugs
Equally Spaced
Manhole Cover
or Grate
2
Manhole Cover Ring
3
Detail (1) can be used with almost any type of surface cover or grate.
Concrete grade ring may be augmented with brick to raise cover
elevation in the future. Alternatively, added concrete may be poured.
Direct connections of cast or fabricated plates or rings as in (2) and (3)
are particularly suitable for grated inlet openings.
Standard cast iron covers and/or steel grates are used with CSP manholes and
catch basins.
1. STEEL SEWER PRODUCTS
29
MANHOLE REINFORCING
Ma
Di nho
am
le
ete
r
Structural Angle
Formed to Fit
Pipe Curvature
Trunk Line
Structural Angle
Use of manhole reinforcing is recommended when trunk line sewer pipe
size is 1600 mm diameter and larger.
MANHOLE SLIP JOINTS
CSP
with Annular Ends
Soft Wood Spacer
Blocks Minimum
4 Required
per Joint
O-Ring Gaskets
If Required
Band
Heavily loaded manholes sometimes make slip joints desirable. Shown
above is one method of providing a slip joint which allows settlement in
the riser.
30
MODERN SEWER DESIGN
MANHOLE LADDER
See Detail A
Double Nuts
not Shown
Steel Rungs
Slotted Joints
Typical Manhole Ladder
Flat Plate
Thru Bolt
Detail A
Typical Ladder Bracket Attachment
Corrugated Manhole
1. Ladder may be constructed in one length.
2. Use bolts with double nuts to connect splice plate at ladder joint to allow
vertical movement.
3. Hot-dip galvanizing of all ladder components is recommended.
1. STEEL SEWER PRODUCTS
31
MANHOLE STEPS
Double Nut
Rung to CSP
Manhole
See
Detail B
Rung
Manhole
Steps
Detail B
Plate Each
Side of
Corrugated
Manhole
Typical Manhole Steps
Step
Step
Alternate Methods for
Attaching Manhole Steps
CPS catch basin with concrete slab and standard cast-iron frame and cover.
32
MODERN SEWER DESIGN
CSP SLOTTED DRAIN INLETS
By welding a narrow section of grating in the top of a corrugated steel
pipe, a continuous grate inlet is achieved. Originally conceived to pick up
sheet flow in roadway medians, parking lots, airports, etc., this product
has proven even more useful in curb inlets.
Slotted drain eliminates hazardous dips in grade, while adding to drainage efficiency.
Slotted drain carries water away from parking area.
1. STEEL SEWER PRODUCTS
33
SPIRAL RIB STEEL PIPE
Spiral rib pipe is manufactured from a continuous strip of metallic coated
steel passed through a forming line that forms the external ribs and prepares the edges. The formed section is then helically wound into pipe and
the edges are joined by lock seaming. The finished product has the structural characteristics needed for installation and a smooth interior for improved hydraulics.
19 mm
19 mm
190 mm
Inside Diameter
of Pipe Wall
Corrugation Profile
Spiral rib pipe installation.
Lengths of pipe arch are easily moved into position.
34
MODERN SEWER DESIGN
PROTECTIVE COATINGS, LININGS AND PAVINGS
SHEETS AND COILS
Corrugated steel pipe is fabricated from steel sheets or coils conforming to
national specifications. The base metal is mill coated with one of several
metallic or non-metallic coatings or a combination thereof.
(a) Metallic Coatings
Most CSP sheets and coils have a zinc coating. Other metallic
coatings using aluminum or aluminum-zinc alloys are also available.
(b) Non-Metallic Coatings
Sheets and coils are available mill coated with non-metallic coatings.
(1) Various polymer films or liquids are applied to one or both sides of
the metal. (2) Fibers are embedded in the molten metallic coating.
PIPE
Fabricated pipe may be bituminous coated, bituminous coated and invert
paved, bituminous coated and fully paved. The pipe may be fully lined
with bituminous material or specially fabricated smooth with external ribs.
Placing coated CSP sewer section. Fabric sling protects pipe coating.
1. STEEL SEWER PRODUCTS
35
Table 1.16 Material description and specifications
Specifications
Material
Description
Zinc Coated
Sheets & Coils
Steel base metal* with 610 g/m2
zinc coating
Polymer Coated Polymer coatings applied to sheets* and
Sheets and Coils coils* as follows: a) one side only, 0.25 mm
b) 0.25 mm one side, 0.07 mm the
other side; c) special ordered combination
AASHTO ASTM
CSA
M-218 A444M
CAN3-G401
M-246 A742M
CAN3-G401
CAN3-G401
Aluminum
Coated Coils
Steel base metal* coated with 305 g/m2
of pure aluminum
M-274
Aluminum-Zinc
Coated Coils
Steel base metal* coated with 214 g/m2
of an aluminum-zinc alloy
M-289 A806M
Sewer and
Drainage pipe
Corrugated pipe fabricated from any of the
above sheets or coils. Pipe is fabricated by
corrugating continuous coils into helical form
with lockseam or welded seam, or by rolling
annular corrugated mill sheets and
riveting seams.
1. Galvanized corrugated steel pipe
M-36 A760M
2. Polymeric pre-coated sewer and drainage M-245 A762M
pipe
3. Aluminized corrugated steel pipe
M-36 A760M
4. Aluminum-Zinc alloy coated corrugated
–
A760M
steel pipe
5. Structural plate pipe
M-167 A761M
A819
–
CAN3-G401
CAN3-G401
CAN-G401
–
CAN-G401
Asphalt Coated Corrugated steel pipe of any of the types
Steel Sewer Pipe shown above with a 1.3 mm, high purity
asphalt cover
M-190
A849
CAN-G401
Invert Paved
Corrugated steel pipe of any one of the types
Steel Sewer Pipe shown above with an asphalt pavement
poured in the invert to cover the corrugation
by 3.2 mm
M-190
A849
CAN-G401
M-190
A849
CAN-G401
M-36
A760M
–
M-243
A849
–
–
D1056
–
–
C361
–
Fully Lined Steel Corrugated steel pipe of the types
Sewer Pipe
shown above
a. with an internal asphalt lining
centrifugally spun in place; or,
b. corrugated steel pipe with a single
thickness of smooth sheet fabricated
with helical ribs projected outward
Cold Applied
Bituminous
Coatings
Fibrated mastic or coal tar base coatings of
various viscosities for field or shop coating
of corrugated pipe or structural plate
Gaskets and
Sealants
1. Standard O-ring gaskets
2. Sponge neoprene sleeve gaskets
3. Gasketing strips, butyl or neoprene
4. Mastic sealant
*Yield point - 230MPa min.; tensile strength - 310MPa min.; elongation (50mm) - 20% min.