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Aug 03, 2005 In general the following techniques of unmanned, steerable pilot pipe jacking, in the literature also known as guided boring, are applied, whereas the jacking is always carried out in two (Abschnitt 3.1.1.1) (Abschnitt 3.1.2) or a maximum of three (Abschnitt 3.1.1.2) sequential phases:
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May 28, 2004 (e.g. methods mts 1000 [FI-mts], RVS 100 A and 250 A [FI-Wirthb])
Method of operation … |
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May 28, 2004 (e.g. methods AVN [FI-Herreb], mts 1000 [FI-mts], RVS 100 AS and 250 AS [FI-Wirthb], MTB-S [FI-Hazem]) (Image: Microtunnelling with hydraulic spoil removal in single phase jacking) Method of operation and sequence Microtunnelling with hydraulic spoil removal is characterized by the jacking of pipes with simultaneous full-face excavation of the mechanically and liquid pressure balanced working face. Further features are a cutting head and continuous … |
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Aug 03, 2005 (e.g. methods AVP [FI-Herreb], MTB-P [FI-Hazem]) (Image: Microtunnelling with pneumatic spoil removal) Method of operation and sequence Microtunnelling with pneumatic spoil removal on the basis of a suction plant is characterized by the jacking of pipes with simultaneous full-surface excavation by a cutting head of the mechanically or earth-pressure balanced working face as well as by the continuous conveying of spoil out of the excavation chamber inside … |
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Aug 03, 2005 The unmanned, steerable microtunnelling techniques employed base generally on the principle of soil removal. Depending on the way of conveying the spoil, it is differentiated between:
In all cases the different soil- and rock types are taken into account by the different … |
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Aug 03, 2005
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Aug 03, 2005 Shafts are usually always necessary for trenchless installation of pipelines with the methods of microtunnelling and pilot pipe jacking. The term shaft is understood to be a depression in the ground surface that is created by sinking (excavation or vertical boring), with suitable support, that serves for the underground creation of bore holes with the aid of the methods of trenchless installation and for the transport of humans, machines, substances (… |
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Aug 03, 2005
The location and the number of shafts are decisively influenced by the lay out of the sewer and the requirements of the trenchless construction method (e.g. realisable jacking length (Abschnitt 4.4), straight … |
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Jun 01, 2004
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Aug 04, 2005 The most widely used method in Germany for securing rectangular shafts, or shafts deviating from the circular, is that of using sheet planks or sheet piles because the construction companies have extensive experience in handling this type of lining and usually also possess the equipment required for it. The steel sheet planks or sheet piles with wall thicknesses between 3 mm and 8 mm are driven into the soil by means of ramming, vibration (shaking) … |
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Jun 01, 2004 An open sinking shaft is a shaft open at the bottom that is usually constructed in sections of in-cast concrete or of prefabricated reinforced concrete elements (Bild 6.4.3) (Bild 6.4.3) (Bild 6.4.3) on a manufacturing platform and that is sunk to its foundation level with simultaneous excavation of the core (Bild 3) (Bild 3) (Bild 3).
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Aug 03, 2005 (Image: Methods for securing shafts [Stein05a]) Decisive for the selection of a method of shaft construction, i.e. the measures for sinking and securing of a shaft, can be, for example [Stein05a] :
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Aug 04, 2005 When opening up the exit and entrance openings with jacking in soil that is free of groundwater, the main task is to avoid ground failure. In the cases in which a bentonite suspension is injected into the annular gap for reducing skin friction, or in which, despite the absence of groundwater, closed shields with fluid support or earth pressure support of the working face are used, care must be taken regarding sealing measures like in saturated subsoils (… |
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Jun 01, 2004 The gasketed opening seal consists of a single or double or duplex elastomeric seal (for high groundwater pressures) (Bild 6.5.2.1) (Bild 6.5.2.1) (Bild 6.5.2.1) (Bild 6.5.2.1) that is attached between the shaft wall and a correspondingly seal fixture. The seal fixture may use a steel fixed flange, an exit or entrance top hat or similar and, if necessary, additional intermediate rings as well as a bolted loose flange often consisting of several segments. … |
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Aug 04, 2005 Their purpose is to provide a transition, without damage, from the atmospheric pressure in the shaft to the groundwater pressure outside in the subsoil in order to permit unhindered exit and entry of the microtunnelling machine at the time of the opening of the shaft lining without additional measures. Pressure chambers always possess two locks and an integrated gasketed opening seal (Abschnitt 6.5.2.1) into which the microtunnelling machine enters. |
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Aug 04, 2005 (Image: Dewatering properties of different types of soils with water retention measures [Herth95]) The following measures are possible in order to prevent ground failure and groundwater inflows when creating and traversing the exit and entry openings [Stein05a] :
The simplest solutions, when technically possible are water retention measures for lowering the groundwater level [Rappe96] [DIN18305]. |
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Aug 04, 2005 Within the scope of microtunnelling and pilot pipe jacking a difference is made between the following phases of jacking [Konra01] :
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Jun 01, 2004 Shafts for drains and sewers consisting of jacking pipes have to correspond to EN 476 [DINEN476:1997] and ATVDVWK A 157E [ATVA157], respectively to the materialrelating shaft standards based on them (e.g. EN 1917 [DINEN1917:2004] and DIN V 4034-1 [Konra01] for shafts of precast concrete- and reinforced concrete elements). A manhole (DN/ID 1000) is usually built into the starting- or target shaft (double shell construction method, respectively shaft-… |
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Aug 03, 2005 |
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Jun 02, 2004 In the steerable methods of microtunnelling and pilot pipe jacking the whole pipe string in the form of a linked chain behind the microtunnelling machine (Bild 8) or the flexible drill rod string must follow the pilot boring head. Thus the bore path must necessarily also be the line and gradient of the final sewer. This means that all deviations from the design position remain almost unchanged as errors. The jacking steering has to ensure that the … |
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Jun 02, 2004 In the Federal Republic of Germany in this method variant, the auger boring method BOHRTEC BM 150 D is also utilised with corresponding modifications [Stein05a]. Here we are concerned with an unmanned, non-steerable technique working in three-phases (Bild 9.1.2.1) (Bild 9.1.2.1) (Bild 9.1.2.1) (Bild 9.1.2.1) (Bild 9.1.2.1) (Bild 9.1.2.1) (Bild 9.1.2.1). Phase 1:
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Aug 04, 2005 (Image: Boring a lateral from a man-accessible sewer (BOHRTEC BM 150 DT method)) In special applications, especially in the making of laterals to man-accessible sewers (≥ DN/ID 1200), the pipe as well as other secured cavaties can take over the function of the starting shaft (Bild 9.1.2.2). The auger boring machine that is used here can be moved into the pipe string by means of a special cart and can be set at the respective connection point to the … |
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Aug 04, 2005 Here we are dealing with a combination of the trenchless installation of the lateral with the underground connection to the sewer. It is differentiated between two variants [Stein05a] :
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Aug 04, 2005 With the construction of the main sewer also drains should be produced. According to EN 752-1 [DINEN752d], a drain is defined as a "pipeline, usually underground, designed to carry wastewater and/or surface water from a source to a sewer." In literature and the regulations also the synonyms connection sewer, service pipe, building connection or lateral can be found. In the following, the term lateral is used. Laterals can be produced with the open-… |
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Mar 22, 2011 This manual is the first to provide a comprehensive, easy-to-understand overview of the possibilities of trenchless pipeline construction for installing non-accessible pipelines and sewers by means of pilot pipe jacking and microtunneling. In 15 chapters with 85 pictures and 26 tables, all important aspects to be considered during planning, construction and acceptance are presented in a practical and easy-to-understand manner, in addition to detailed descriptions of the procedures and methods. Furthermore, topics jacking pipes, geotechnical investigations, starting- and target shafts, obstacle problems, steering and monitoring, lateral connection, work safety and health protection, planning, and economic considerations are also covered. |
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