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Nov 02, 2004 The advantages of various materials combine the concrete and reinforced concrete pipes with a corrosion protection applied directly during the production of the pipes for use in sewer systems with unavoidable and constant "very strong" chemical aggressors to DIN 4030 [DIN4030-1:1991] and ATV-M168 [ATVM168] . This is a pipe with one or two layers, the carrier layer and the corrosion protection layer (lining or coating). The carrier layer is formed … |
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Feb 16, 2011 (Image: In-situ concrete with reversed ovoid cross section [Frühl10]) The large pipe diameters of prefabricated pipes inevitably lead to high transport weights that require heavy transport and lifting machinery. This was the reason for the very early production of in-situ concrete sewers with ovoid cross sections greater than 1000/1500 or circular cross sections > DN 2000 by the open cut method of construction involving the use of special forms [Frühl10]. |
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Nov 02, 2004 Concrete is a building material of natural or artificial crushed granules, which are encased by a binder in the liquid condition (fresh concrete) and in the hardened condition of the binder are permanently cemented by it (hard concrete). The following discussion confines itself to cement concretes whose binder consists exclusively of cement. The production of concrete pipes was begun in Germany about 1850 immediately after the building of the first … |
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Feb 16, 2011 Polymerised concrete consists of a mixture of mineral, quartzite fillers in the hardly porous grading curve range to DIN 1045 [DIN1045:1988] and reaction resin on the basis of unsaturated polyester resins with properties to DIN 16946 Part 2 Table 3 [DIN16946:1989]. The material properties are made up as follows [FI-Meyerb] :
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Nov 02, 2004 After it was recognised what grave health dangers the handling of asbestos could cause, the fibre cement industry promised the Federal Government of Germany within the framework of "Ways out of Asbestos" in the mining area, to change over to an asbestos-free material technology by the latest at the end of 1993. The new asbestos-free fibre cement pipes are produced by machines from an internally homogeneous mixture of cement with the addition of synthetic … |
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Nov 02, 2004 From about 1930 up to the end of the 80s, asbestos cement pipes produced by the winding process from a homogeneous mixture of asbestos, cement and water were used in sewer systems [Asbest77]. A survey of standards, nominal sizes and areas of application that apply to asbestos cement pipes is given in Tabelle 1.7.9. (Table: Overview of the Standardsand areas of application of asbestos cement pipes to DIN 2410 Part 4 (02.78) [DIN2410]) Because of the … |
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Feb 16, 2011 Pipes made of glass fibre reinforced plastics (GRP) have been produced since the start of the 60's of the 20th Century. Originally, they were used for the discharge of aggressive effluents in industrial undertakings but then became increasingly important in the sewage sector where they are laid by the open construction method [Bloom84] [Bloom86] as gravity sewers or pressure pipes (DN 100 to DN 2800, lengths: 6 m, pressures to PN 25). In the trenchless … |
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(Image: Complete manhole base unit of reinforced concrete with butt and rocker pipes [FI-Hupfe]) As the native ground is disturbed and thus becomes prone to settling when manholes are built, it must be expected that positional alteration between manhole and pipes will take place. For a long time, no attention was paid to this problem so that relatively much damage has occurred in the laterals in the form of lateral cracks. Already in the 70's of the … |
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(Image: Pre-cast concrete climbing ladder system [FI-allbe]) Shafts must be equipped with climbing aids - single row or double row climbing steps or fixed or movable climbing ladders. Besides the climbing aids of the traditional climbing steps, concrete climbing ladders or climbing step systems that are formed at the time of the manufacture of the shaft ring or cone have also been available for a few years (Bild 1.8.2). |
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(Image: Concrete inspection chamber [FI-Betonb] - Section) The EN 752-1 [DINEN752e] defines an inspection chamber as follows: "Chamber with removable cover constructed on a drain or sewer that provides access from surface level only, but does not permit entry of a person." Inspection chambers must correspond to the operational requirements of ATV-A 241E, edition 1995 [ATVA241a] especially as regards ventilation, inspection and cleaning. Thus, their … |
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Nov 02, 2004 Rehabilitation and Maintenance of Drains and Sewers Structure and Limiting Conditions of Sewer Systems - Historical Outline In the structures of drain and sewer systems there are also included, besides manholes, structures for overcoming height differences, inspection chamber, intersection structures, storm water overflow works, infall works (street drainage) and outfall as well as valve works (Bild 1.2). The largest share of the structures of drain and sewer systems goes to manholes to EN 476 [DINEN476:1997]. For this reason, these and the inspection chamber to EN 476 … |
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Nov 02, 2004 Private domain sewers are "Inaccessible pipelines laid in the earth or in the foundation that usually carry sewage to the lateral" [DIN1986:1998] (Bild 1.9.1) (Bild 1.9.1) (Bild 1.9.1).
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Feb 16, 2011 The greatest problem with our sewer systems is doubtless the laterals or drainpipes to EN 752-1 [DINEN752e] of drain system, as well as the street run-offs and their connection into the public, non-man-accessible sewers (Abschnitt 2.3.1) (Abschnitt 2.9) [Stein84f]. (Image: Masonry sewer (ovoid profile) with inlets [Benze21]) According to ATV-A 241E [ATVA241a] of the year 1978, the laterals "should, as a rule discharge into the sewers outside of the … |
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Feb 16, 2011 Rehabilitation and Maintenance of Drains and Sewers Structure and Limiting Conditions of Sewer Systems - Historical Outline
The reasons for the necessity for ventilation and venting of sewer systems were stated by König in 1902 [FI-Stein96] as follows: "A sufficient exchange of air is essential as well for health reasons as also in consideration of an undisturbed operation within a … |
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Feb 16, 2011 Rehabilitation and Maintenance of Drains and Sewers Structure and Limiting Conditions of Sewer Systems - Historical Outline
In the rehabilitation of sewer systems, neighbouring or crossing supply lines ranging from telephone cables to district heating piping may cause considerable difficulties. Therefore, their position to the defective sewer, their structural condition and the condition of the surrounding embedment are important criteria for the selection … |
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Feb 16, 2011 Rehabilitation and Maintenance of Drains and Sewers Structure and Limiting Conditions of Sewer Systems - Historical Outline Fine trees were once a sign of wealth and vitality of a town. After this had long been forgotten and trees became the victim, for instance, of the improvement of street traffic, there has been an increasing tendency for some years in the towns and communities of the Federal Republic of Germany to plan and undertake measures for the introduction of greenery - even in connection with easing traffic flow. Trees are an important component of the city … |
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Feb 16, 2011 Sewer systems are constantly or intermittently subject to differing physical, chemical, bio-chemical and biological stresses. Depending on
these stresses can lead sooner or later to the depletion of the originally available wear reserve of 100 % (Bild 2.1) (Abschnitt 4.1) [ATVM143-1:1989] [ATVM143-2b]. |
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Leaks are present when water obviously enters or leaves or when a test for leaks (Abschnitt 4.5.1) is not successful. According to [ATVM143-1:1989], leaks can occur with or without recognisable other damage in
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Feb 16, 2011
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Feb 16, 2011
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Feb 16, 2011 (for types of pipe joints (Abschnitt 1.7.1) ; requirements see DIN 19543) [DIN19543:1982]
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Nov 03, 2004
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