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Jul 06, 2007 Trenchless Technology for Installation of Cables and Pipelines Measurement with onboard apparatus (dynamic survey traverse measurement) Representatives of the survey traverse measurement with onboard Servo Total Station include:
The … |
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Jul 06, 2007 Trenchless Technology for Installation of Cables and Pipelines Measurement with onboard apparatus (dynamic survey traverse measurement) (Image: System overview of the NELS curve measuring system with reference to [FI-Herre98] [Image: S&P GmbH]) In place of an onboard Servo Total Station as well as the connection to survey prisms for survey traverse measurement, use can also be made of a gyroscope in connection with a directional laser. A representative of the measuring system "onboard gyroscope with directional laser" is the NELS curve measurement system (Bild 11.3.2.2.2) [FI-Herreb]. … |
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Jul 06, 2007 Trenchless Technology for Installation of Cables and Pipelines Measurement with onboard apparatus (dynamic survey traverse measurement)
This automatic survey traverse measurement is a measurement whose quality is dependent, among others, on the accuracy of the direction transfer in the starting shaft, the accuracy of the measurements in the pipe string and the … |
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Jul 06, 2007 Trenchless Technology for Installation of Cables and Pipelines Measurement methods utilizing the previously described instruments
From DN/ID 1000, measurement systems with North seeking gyroscopes offer the possibility of determining the precise direction and position of the microtunnelling or shield machine in the man-accessible … |
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EN 12889 [DINEN12889:2000] and ATV-A 125E [ATVA125:1996] prescribe that the following measurement data should preferably be automatically acquired and displayed for monitoring the jacking:
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(Image: Installation of a manhole after completion of the jacking works - Starting shaft secured with the spray concrete construction method [Köln91]) Shafts are usually always necessary for trenchless installation of pipes and cables with unmanned, non steerable techniques (Abschnitt 5), unmanned, steerable soil displacement techniques (Abschnitt 6), pilot pipe jacking (Abschnitt 7.1), microtunnelling (Abschnitt 8.1) and pipe jacking (Abschnitt 9.1). |
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The locality and the number of shafts are greatly influenced by the lay out of the planned line to be jacked. For this reason, it is recommended when planning the line system to take into account right from the start … |
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(Image: Cross sectional shapes of starting and target shafts) The shape and dimensions of shafts should be planned and built under the aspect of minimising expected emissions and construction costs as well as work and health protection. Shafts in which work is carried out must have sufficient working space. The dimensions of the working space depend on the slope angle, lining, equipment, type of pipe and method of working [BGVC22] . At present, three … |
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Shaft construction is understood to be the method of sinking and securing of shafts [Olsha91]. 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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The simplest application form is presented by shafts with sloped walls (Bild 12.5.1) (Bild 12.5.1).
The inclination of the slope is suited to the subsoil (physical properties of the in-situ soil types, water conditions), the utilization of the adjoining surfaces (traffic paths, … |
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With standard horizontal linings to DIN 4124 [DIN4124:2002], the shaft walls are progressively lined during the excavation from the top to the bottom with horizontal, closely fitted wooden planks, sheet planks or similar and these are usually secured with vertical wale timbers and supported by bracing (Bild 12.5.2.1) (Bild 12.5.2.1) [Riege00b].
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With standard vertical lining to DIN 4124 [DIN4124:2002], wooden planks or sheet planks are progressively installed with the excavation or, in soft cohesive soil, are first driven vertically into the soil so that in all construction state, their points are at least 0.30 m in the soil. The earth or traffic loads acting on the vertical wooden planks or plank sheets are diverted into horizontal wale timbers or steel profiles that are installed in the … |
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Non-removable (lost) linings (Bild 12.4) are understood in the case of trenchless installation to be covering, bracing and anchoring structures which are left partially or wholly in the subsoil after completion of the jacking or construction works. Thus, this method of lining offers the ability to use the structural shell as a network structure for operation and servicing in the form of a single or double shell lining (Abschnitt 12.2). The disadvantages … |
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In closed sinking shafts, a massive pressure retaining cover with the side cutters forms a working chamber open to the bottom through which the water for sinking is forced out by means of compressed air. Air locks and shaft pipes make the working chamber accessible and the excavation base open for loosening and conveying the soil (Abschnitt 9.2.1.2.3) [Linge97]. This form of sinking shaft [Linge97] [Breck84] [Niema70] is relatively seldom used in trenchless … |
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(Image: Sinking shafts of prefabricated rectangular reinforced concrete elements - Upper parts of shafts (left) and lower parts of shafts with steel cutters (hanging) [FI-Meyera]) Sinking shafts of shaft rings or shaft elements are used as starting shafts for jacking pipes in the nominal size range ≤ DN/ID 800 (especially microtunnelling and pilot pipe jacking) depending on the nominal size and length of the jacking pipes and the elements are quasi … |
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(Image: Sinking shaft (internal diameter 5.0 m) of bolted reinforced concrete segments [Clark92]) For construction sites with difficult access and for shaft diameters > DN/ID 3200 and/or greater sinking depths (> 10 m), the factory prefabricated sinking shafts of shaft rings or shaft elements can no longer be transported due to their great dimensions (Abschnitt 9.1) and for structural reasons can no longer be inserted. Besides the open sinking shafts … |
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(Image: Target shaft for removing the shield machine from the North Sea in the "Europipe" pipe jacking project (Bild 9.2.2.5.8) (Bild 9.2.2.5.8) [FI-Herreb]) The preferred areas of application of open sinking shafts of steel in the form of steel pipes or welded cylinders ranges to shaft diameters DN/ID 2500 (Abschnitt 12.5.2.5) (Abschnitt 12.7.2). In special cases, steel sinking shafts of greater diameters are used such as in the construction of the … |
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