Bonded Strand Post-Tensioning System

Corrugated Duct

Metal ducts represent the most economical means to create a void for tensile elements. These thin-walled (0.25 - 0.60 mm), ribbed sheet metal ducts provide a fair secondary corrosion protection with excellent bond behavior between tendon and concrete. Primary corrosion protection is provided by the alkalinity of grout and concrete.

 

The tendon type number (e.g. 5901, 6801) is composed as follows:

  • the first digit (5 or 6) identifies the nominal strand diameter in tenth of inches, i.e. 0.5" or 0.6"/ 0.62",
  • the last two digits (..01) reference the number of used strands (= 1 strand)
  • The second digit is an internal code

As regards the 0.6" tendon types, the accessories fit both Grade 250 (GUTS 1770 N/mm2) and Grade 270 (GUTS 1860 N/mm2) strands

Dimensions of Corrugated Duct

(Standard Sizes)

tendon type tendon type sheathing
0.5" 0.6" I.D. O.D.
mm mm
5901 6801 20 25
5902 6802 40 45
5903 6803 50 55
5904 6804 55 60
5905 6805 60 65
5907 6806 65 70
5909 6807 65 70
5912 6809 75 80
5915 6812 80 85
5920 6815 90 95
5927 6819 95 100
5932 6822 100 105
5937 6827 110 118
- 6831 120 128
- 6837 130 138

 

 

 

tendon type tendon type min. center distances support distances up to wobble anchor ß  friction coefficient
0.5 0.6 mm m rad/m rad -1
5901 6801 36 1.8 14*10-30.15
5902 6802 72 1.8 9 * 10 -3 0.17
5903 6803 90 1.8 5 * 10 -3 0.18
5904 6804 99 1.8 5 * 10 -3 0.19
5905 6805 108 1.8 5 * 10 -3 0.20
5907 6806 117 1.8 5 * 10 -3 0.19
5909 6807 117 1.8 5 * 10 -3 0.19
5912 6809 117 1.8 5 * 10 -3 0.19
5915 6812 144 1.8 5 * 10 -3 0.19
5920 6815 162 1.8 5 * 10 -3 0.19
5927 6819 171 1.8 5 * 10 -3 0.20
5932 6822 180 1.8 5 * 10 -3 0.20
5937 6827 198 1.8 5 * 10 -3 0.20
- 6831 216 1.8 5 * 10 -3 0.20
- 6837 235 1.8 5 * 10 -3 0.20
1) according to European Technical Approval

PE/PP Round Duct


Thick-walled polyethylene/polypropylene plastic ducts provide long-term secondary corrosion protection especially in aggressive environments such as in the case of waste water treatment plants, acid tanks, silos or structures exposed to de-icing salts.

DYWIDAG-Systems International offers polyethylene/polypropylene ducts in straight lengths up to ~24 m for all sizes. Standard shipping length is ~12 m. Longer lengths in coils are available for all sizes except 130 mm.

Dimensions of Round Corrugated PE/PP Duct (Standard Size)
tendon type tendon type sheathing wall thickness
0.5" 0.6" I.D. O.D. t
mm mm mm
5907 6805 59 73 2
5909 6807 59 73 2
5912 6809 76 91 2.54
5915 6812 84 100 2.54
5920 6815 100 115 2.54
5927 6819 100 115 2.54
5937 6827 115 136 3.56
  6837 130 151 3.56
Flat PE/PP Duct
type tendon type A B a b wall thickness
0.6" mm mm mm mm mm
flat duct 6804 90.2 39.5 80 29 2