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According to EN 12889, "the installation shall not commence before the following criteria have been agreed between the specifier and installer. These may be obtained from appropriate product standards or from the pipe manufacturer: -
Internal pipe diameter
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External pipe diameter
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Pipe length
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Tolerances on dimensions
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Safe jacking load or pulling force
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Type and performance of joints
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Longitudinal flexibility (acceptable bending …
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Dimensions of pipes and fittings: The product standards must provide information on nominal sizes, diameters and tolerances, straightness, rectangularity of end faces, pipe length and continuity of invert. The roughness of pipe wall: Inside walls of pipes must be free of visible defects that may negatively affect their hydraulic performance. Condition: Pipes and joints shall be free of defects that may have a negative impact on … |
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Jetting resistance: Pipes must be resistant to stress resulting from jetting. Modification: Manufacturers must provide information on in-situ handling. Coatings and linings: If coatings, linings or other protective measures are required, it is necessary to specify appropriate indications in product standards, also in consideration of the installation. It may be necessary to specify additional protections for joints. Long-term behaviour: |
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Load-bearing capacity and stiffness: The following values are particularly necessary for the calculation of the characteristic mechanical behaviour of pipes in dependence of the type of their installation, their use and material: modulus of elasticity, density, tensile strength, yield limit, compressive strength, bending strength, longitudinal compressive strength and vibration amplitude. Temperature: Pipes and joints shall be … |
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The perpendicularity of end faces (perpendicularity of the pipe axis) of jacking pipes for gas, water as well as drains and sewers is of particular importance for transferring the jacking forces when pushing-in, pressing-in or ramming-in and for the dimensioning of the pressure transfer ring [ [DWAA125:2014]]. |
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(Image: Measurement of the rectangularity of end faces) |
The perpendicularity of the end surface is defined according … |
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(Table: Permissible deviations of the rectangularity of the end faces with reference to the pipe material and the nominal size in mm) |
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In determining the pipe length of the jacking pipe to be inserted (pipe length plus when available, the thickness of the pressure transfer ring in the uncompressed condition), the installation method must be taken into account. |
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(Table: Permissible pipe length tolerances with reference to the nominal size of the jacking pipes) |
Preferred lengths of jacking pipes for pressing- in, pushing-in or ramming-in are 1000 mm, 2000 mm, … |
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| Tightness against internal and external pressure
(Image: Leaktightness)
| Transfer of the longitudinal force by securing the lateral stability (Image: Transfer of the longitudinal force)
| Possibly corrosion protection of the end faces of the pipe
(Image: Corrosion protection end faces of the pipe)
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(Image: Leaktightness) |
All parts of the pipeline including the pipe joints and sealings must be designed, produced and examined according to the objective to guarantee the tightness during the construction works (construction state) and the whole planned service life (operation state) taking the long-term properties of the sealing medium as well as potential movements of the pipe joints under the respective loads into consideration. |
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(Image: … |
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(Image: Transfer of the longitudinal force) |
In the case of trenchless installation, differences are made with regards to the transfer of the jacking forces between the following restrained pipe joints: -
Non-restrained pipe joints for transferring compressive stresses when pressing-in or pushing-in [ [DWAA161:2017]]1
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Tensile restrained pipe joints for transferring tensile forces when pulling-in
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Restrained pipe joints for transferring compressive …
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(Image: Corrosion protection end faces of the pipe) |
To protect the end faces of the pipe against corrosion, plastic sealing materials are used as joint closure.
The use of plastic sealing material prevents aggressive wastewater from entering the pipe joint and from causing corrosion. |
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| (Image: Adhesive joint)
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Glued joint A glued joint is a rigid, restrained pipe joint whose sealing effect is achieved by gluing together the pipe ends to be joined. | | (Image: Welding bead)
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Welded joint A welded joint is a rigid, restrained pipe joint whose sealing effect is achieved by welding the pipe ends together. | | (Image: Screwed joint)
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Screwed joint A screwed joint is a rigid, restrained pipe joint, whose sealing effect is achieved by the screwed … |
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(Image: Pressure transfer over the inner or outer front face of a lip joint with reference to [BS5911] - with rolling ring [Image: S&P GmbH]) |
Socket and spigot joint A flexible, non-restrained socket and spigot joint for jacking pipes is a pipe joint whose sealing effect is achieved by the joining of the plug-in end with a connector (collar, coupling, sleeve, loose guide ring) and connecting the plug end (spigot) and the socket or rebate or guide … |
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(Image: Elastic sealing media) |
Elastic sealing media
Elastic sealing media are sealing elements made of elastomers, which are inserted into the joints to be sealed by elastic deformation. Their sealing effect against fluids or gases under pressure depends on the rubbery-elastic restoring forces developing from the deformations of the sealing elements. |
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(Image: Plasticised sealing medium) |
Plasticised sealing medium Plasticised sealing media are … |
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(Image: Production of concrete pipes) Concrete is a material of natural or artificial aggregates that are coated by a binder-water mixture (fresh concrete) and, in the hardened condition of the binder, are permanently cemented into it (fixed concrete). The following discussions refer to cement concretes according to DIN 1045 whose binder is made exclusively of cement with some pozzolanic or latently hydraulic additives. [ [DIN1045:2001]]1 1Please refer … |
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(Image: Concrete pipe)
Concrete pipe:
Pipe that does not contain structural steel reinforcement or steel fibre strengthening [ [DINEN1916:2003]]1. |
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(Image: Reinforced concrete pipe)
Reinforced concrete pipe:
Pipe that is structurally reinforced with one or more steel cages, suitably positioned to resist tensile stresses in the pipe wall [ [DINEN1916:2003]]1. |
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(Image: Steel fibre concrete pipe)
Steel fibre concrete pipe:
Pipe that is structurally … |
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(Image: Concrete pipe) |
Concrete jacking pipes in accordance with EN 1916 are predominantly used for unmanned jacking works in a nominal size range < DN 1000 (40 in). |
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(Image: Reinforced concrete pipe) |
Reinforced concrete jacking pipes in accordance with EN 1916 are marked by their wide adaptability to structural, constructive and operational requirements. This is why they are suitable for very long jacking distances, for scheduled curved line … |
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(Image: Reinforced concrete jacking pipe) (Image: Reinforced concrete jacking pipe - Double seal in spigot end) (Image: Reinforced concrete jacking pipe - Safety bolt against rolling of the pipe string) (Image: Reinforced concrete jacking pipe - Steel guide ring, pressure transmission ring made of wood and opening for securing bolts against rolling of the pipe string) (Image: Reinforced concrete jacking pipe - Equipped with lubrication station) |
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(Table: European standards for concrete and reinforced concrete pipes (as at 10.2008)) Table 2: Other Standards and Guidelines
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American Concrete Pipe Association. (2020). ASTM Standards on Concrete Pipe. Retrieved from https://www.concretepipe.org/specifications/astm/ |
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ASTM. (2018). ASTM C1208 / C1208M - 18 Standard Specification for Vitrified Clay Pipe and Joints for Use in Microtunneling, Sliplining, Pipe Bursting, and Tunnels |
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AWWA. (2008). Concrete … |
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Special attention must be paid to corrosion resistance of cement-bound materials against attacks by sewage and influences of soil and groundwater. |
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Causes of external corrosion -
non-observation of the limiting values of the standards and guidelines
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soil and groundwater aggressiveness
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aggressive substances discharge into the soil or the groundwater
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lacking, unprofessionally fabricated or damaged corrosion protection
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Causes … |
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For concrete / reinforced concrete jacking pipes the following corrosion protection measures come into question: -
Measures regarding concrete-technology during fabrication of the jacking pipes to increase material resistance against external and internal corrosion
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Internal lining of the jacking pipes with other, corrosion-resistant material (material combinations)
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Joint closure of the pipe joint or inner sealing to protect the end faces of the pipe
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The advantages of various materials unite the concrete and reinforced concrete with a factory-made internal corrosion protection that is applied during pipe manufacture for use in gravity drainage systems (sewer systems) with unavoidable and constantly "very strong" chemical attacks. | |
Here, we are dealing with a pipe consisting of two layers, namely a base layer and a corrosion protection layer (lining, inliner). The different … |
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Possible material combinations are: -
Reinforced-concrete-vitrified-clay jacking pipes
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KeraLine jacking pipe
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Concrete/reinforced-concrete-plastic pipes
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Reinforced-concrete-GRP jacking pipes
(Image: Reinforced concrete jacking pipe with inner lining of plastics) (Image: BKU reinforced concrete jacking pipes - View) (Image: Concrete pipe with invert lining of cast-basalt elements) (Image: Concrete pipe with vitrified clay plates) |
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According to EN 1916, jacking pipes for gravity pipelines of concrete, reinforced concrete and steel fibre concrete must possess in-wall flexible nonrestrained joints either with a guide ring (in EN 1916 called collar) or a rebate joint. They must be designed in such a way that one or more seals can be used. [ [DINEN1916:2003]] |
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All joint surfaces which will transmit load during installation shall be plane and free from irregularities … |
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