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Dec 01, 2017 After the curing of the cement-based grout in the annular space, the connections of lateral drains and sewers, which has been provisionally sealed in the context of preliminary work, will be connected close to the spirally-wound pipe either from the outside by open cut method by means of a fitting or from the inside. When connecting from the inside, the opening required is made by hand in the case of man-accessible sewers. In the case of non-man-… |
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Nov 21, 2017 |
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Dec 01, 2017 (Image: Picto Desk Task) In order to ensure professional rehabilitation of the sewer by means of a spiral wound lining, in addition to quality assurance, a professional planning, execution and testing is required. The quality assurance consists of a self- and external monitoring for the working phases:
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Dec 01, 2017 Quality assurance also includes the correct storage of the plastics profiles and of the grouting material. When storing the plastics profile coils, the following aspects must be taken into account:
If the cement-based grout is used as bagged goods on the construction site, … |
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Dec 01, 2017 (Image: Picto FactsandFigures) As part of the self-monitoring, all working steps required in the production of the spirally-wound pipes must be documented. This can be done according to a manual with process description / instructions as stated in EN ISO 11296-7. All documented working steps are to be checked with the requirements of the proofs of suitability. [ENISO11296-7:2013] |
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Dec 01, 2017 Each delivery of the plastics profiles in a construction project must be checked based on their marking for compliance with the information provided in the proofs of suitability. The marking of the plastics profiles have to be durable and clearly legible and according to EN ISO 11296-1 the following minimum information must be included:
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Dec 01, 2017 For spiral wound lining with annular space grouting, the water filling can also be used for the leak-tightness test of the spirally-wound pipe with non-grouted annular space according to EN 1610 [EN1610:2015]. Before the annular space grouting starts, the theoretical volume of the cement-based grout must be calculated. The grouting amount and the theoretically calculated quantity are to be recorded. During the winding process, one has to ensure that … |
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Dec 01, 2017 By means of the preceding marking, a review of the material properties of the plastics profile is possible at any time, so that it is not necessary to take a sample. If the profiles used are not marked as required, it is also recommended to remove a retention sample from the plastics profile. For each rehabilitation section (one or more contiguous sewer sections) samples of the grout are to be recovered as retention samples. These are to be handed … |
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Dec 01, 2017 (Image: Picto Desk Task) The external monitoring includes at least one annual inspection of the following:
The results of external monitoring have to be documented. |
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Dec 01, 2017 As part of the acceptance of construction work, the following testings are to be carried out:
(Image: With spirally-wound pipe lined sewer) (Image: Principle … |
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Dec 01, 2017 With regard to the contractor's qualifications, clients are obliged to exercise due care in the assignment of the rehabilitation efforts and to request the required qualifications or to convince themselves of such qualifications of the contractor. Quality assurance should contain requirements for:. Details on this can be found in DIN 1960 (VOB/A § 8 para. 3). Quality assurance GZ 961 [RALGZ961:2016] contains requirements for:
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Nov 21, 2017 |
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Dec 01, 2017 The basis for the static calculation of drains and sewers with lining and segmental lining processes is DWA-A 143-2 [DWA-A 143-2]. The DWA-A 143-2 is divided into the following five main chapters:
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Dec 01, 2017 The technical specifications are dealt in section 4 of [DWA-A 143-2:2015]. It contains all the materials PVC, PE-HD and steel with their short- and long-term values used in the spiral wound lining, so that the material parameters required for the static calculation as input parameters are available. |
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Dec 04, 2017 Section 5 of [DWA-A 143-2:2015] first describes the preliminary works to be carried out before the construction (rehabilitation). These include inter alia:
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Dec 04, 2017 The set of rules DWA-A-143-2 basically distinguishes between three states of the host pipe: Host pipe state I: The host pipe is stable on its own. The liner is strained only by its dead weight and by water pressure. Host pipe state II: The host pipe is not stable on its own, but the host pipe soil system is stable. The liner is strained only by its dead weight and by water pressure. Host pipe state III: The host pipe / soil-system is not durable stable. … |
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Dec 04, 2017 According to DWA-A 143 imperfections are to be used in principle, because liners are generally slender constructions and at external water pressure are stressed by high compressive stresses. This causes a high sensitivity with regard to the stability behavior and / or additional bending stresses as a result of pre-deformations (deviations, for example, from the circular shape). In the calculation, local pre-deformations, joint ring pre-deformations (… |
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Dec 04, 2017 (Image: Old-pipe state I) In the host pipe state I, in the case of a spiral wound lining with annular space grouting, a local limited pre-deformation is to be applied, the stitch of which corresponds to 1% of the liner radius in the spirally-wound pipe. It is composed of a substitute imperfection for detecting geometric pre-deformations and further disturbances in the liner and in the host pipe. In addition, a gap between liner and old pipe must be … |
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Dec 04, 2017 (Image: Old-pipe state II) In the host pipe state II, a joint ring pre-deformation (ovalization at the rate of 3% of the liner radius) in addition to the local limited pre-deformation has to be assumed, since in the corresponding static model, the host sewer is broken four times and first has to become deformed in order to activate the required bedding effect of the soil. While in close-fit methods the spirally-wound pipe follows the inner contour … |
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Dec 04, 2017 (Image: Old-pipe state III) In the host pipe state III, the imperfection of the local pre-deformation is omitted. The gap formation must not be assumed, because unlike the host pipe states I and II, it reduces the computational stress on the liner. The remaining imperfection of joint ring pre-deformation only has an effect on the spiral wound lining without annular space grouting, so that no imperfection must be taken into account in the case of … |
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Dec 04, 2017 In addition to the proofs of stress, stability and deformation in modified form, the following proofs must be provided:
(Image: Sectional view of the completed liner - the webs are completely enclosed by the cured Dämmer®) With regard to the spiral wound lining profiles, the required cross-sectional values (area, moment of inertia, section modulus) are … |
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Dec 04, 2017 In addition, the webs are to be calculated in terms of stability depending on the profile bowing and the effects due to external loads. The objective of a corresponding investigation would be the statement that a failure of profile parts under all effects occurs later than the failure of the overall cross-section. In doing so one could do without the proof of the sufficient profile stability in the individual case. |
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Dec 04, 2017 (Image: Work safety)During the winding process, the profile is deformed by the winding machine according to the desired geometry and by the connection to the adjacent turns and brought into a "strained" final state. Thereby, in accordance with the deliberate bowings generated in the process, elastic or possibly also plastic distortions and thus also associated internal stresses, which must be superimposed with the stresses from external loads, arise … |
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Nov 21, 2017 |
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Jan 31, 2023 The “lining with spirally-wound pipes” process is assigned to the group of lining processes with locally produced pipes. The characteristic of this method is the production of a spirally formed self-supporting or static load-bearing liner on-site, from factory-made extruded plastic profiles with the help of a winding machine.
After completing this module, you will have a sound knowledge of:
- areas and limits of application
- materials and profiles;
- requirements for planning and work preparation;
- work sequence for lining with spirally-wound pipes with stationary coiling machine in the launch shaft;
- requirements and the sequence for annular space grouting;
- requirements for quality assurance.
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