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A man-accessible utility tunnel, also called utility corridor or utilidor, is an enclosed corridor-like structure for the accessible installation of supply and/or disposal lines consisting of utility tunnel path as well as access, erection, ventilating, branch and joining structures [Stein02] [Stein94a] [Stein97d] [Stein98e]. Besides the functions of the utility duct (Abschnitt 2.2.3), the man-accessible utility tunnel as a geometrically restricted … |
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Product pipes, whose cross-sectional area is not fully utilized during operation, can also be used as line and gradient for other product lines. This idea is not new. For instance, the sewers of Paris, since their construction in the 19th Century, have been used at the same time for the installation of water, compressed air and cable lines (Bild 2.2.5) (Bild 2.2.5). These are installed in the upper part that is free even during heavy runoffs [Hobre90] … |
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(Image: Variations of the trenchless installation of lines) Multiple installation is understood to be the shared installation of several lines (one after the other or altogether), which may also be of different types, in the same line and gradient. It can be carried out by means of (Bild 2.2) :
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(Image: Variations of the trenchless installation of lines) In trenchless installation of cables and pipelines, a principal distinction can be made between the installation of single lines (single installation), or the joint installation of several lines, which may also be of different types, in the same line and gradient (multiple installation). An overview of further divisions can be found in Bild 2. |
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The term "Trenchless Technology for Installation of Cables and Pipelines by Jacking or Drilling" (referred to hereareafter as trenchless installation), is understood to mean "The Underground installation of lines by means of pulling in, pushing in, pressing in or ramming in into a cavity (borehole) made in the soil by means of boring or drilling." Influenced by DIN 20301 [DIN20301], boring or drilling is designated as the mechanised creation of a … |
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With tunnelling and gallery heading there are a variety of approaches for securing and/or lining the opened up cavity with reference, for instance, to the construction method, the stability of the subsoil and the utilization of in-cast concrete, sprayed concrete or prefabricated segments. In trenchless installation of cables and pipes, these can take on the duty of product pipes, casing and host pipes, utility ducts or structural shells for man-accessible … |
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In this book, the term Trenchless Technology for Installation of Cables and Pipelines is understood to include the installation of supply and disposal lines (product lines), casing and host pipes, utility ducts and structural shells of man-accessible utility tunnels [Stein02] - all installed using trenchless methods of construction, e.g. without the excavation of trenches. The open cut method cannot be completely avoided but is used only to a limited … |
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(Image: Scientific disciplines of geotechnology with reference to [Floss00] [Image: S&P GmbH]) Geotechnology is a branch of civil engineering concerned with soil or rock as a subsoil and structural material and with the means for investigating its condition and structural utility for construction of stable and functional structures [Schmi96]. The following scientific disciplines, among others, belong to the Geotechnology subject area (Bild 4.1) [Schmi96] : |
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The crust of the earth consists mostly of rock materials that are made up of naturally formed quantities of different minerals (mineral aggregates) or of only one mineral type. This can occur as soil or as rock and sometimes of both in sequence. Soil occurs through the weathering of rock. It exists either in original strata (weathered soils) or has been transported by wind, water or ice and deposited (sediments) (Abschnitt 4.5.1) [Soos96]. Rock is … |
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With non-cohesive soils, the individual particles or parts of the rock material form an agglomeration that possesses a measure of strength due to the friction of the particle surfaces. Their properties are influenced by the particles size, particle size distribution, particle form and particle roughness. Depending on the base material, they are often resistant to weather conditions. According to DIN 1054 [DIN1054:2005], the non-cohesive soils comprise … |
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With cohesive soils, the particles adhere to each other due to electrostatic surface forces and thus form an interconnected formable mass. Their properties (strength behaviour) are influenced largely by the water content, the particle size and the clay mineral content (Abschnitt 4.3.1.5). They are sensitive to weathering. According to DIN 1054 [DIN1054:2005], this type of soil comprises clays, clayey silts, and silts (e.g. sandy clay, sandy silt, … |
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According to DIN 1054 [DIN1054:2005], this type of soil comprises peat or sapropel and inorganic soils with organic admixtures of animal or plant origin (Tabelle 4.3.1.1.3), when the weight percentage is more than 3% or 5% (e.g. sand containing humus, sapropel, or sand containing peat, organic silt or clay, loam). Depending on the degree of decay, such soils possess a fibrous, fleecy or earthy texture and a high degree of water retention or water … |
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Also, according to ISO14688-1 [DINENISO14688:2004], volcanic soils are understood to be, "pyroplastic materials produced and formed by explosive volcanic eruption; e.g. pumice, scoria, volcanic ash." The particles of volcanic soils are generally blistered and the compactness or density of the strata (Abschnitt 4.3.1.4) is relatively low. The soils possess a characteristic colour that depends on the original magma or rock. The main components of … |
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With fine soils, the shape of the particle is solely dependent on the type of the mineral. Quartz, lime and dolomite are generally cubic, clay minerals generally flat and halloysite is longitudinal (elongated). With coarse soils, the particle shape and the roughness is dependent on the type of rock material as well as the transport and weathering history. Increasing transport distances leads to rounding of the edges and the smoothing of the particle. … |
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(Image: Flow chart for the identification and description of soils based on ISO 14688-1 [DINENISO14688a]) The primary differentiating feature of mineral soils is the size of the individual particles. This determination is the first step in the identification and classification of a soil type (Bild 4.3.1.3). A review of the identification of the type of soil with reference to particle size is shown in Tabelle 4.3.1.3. (Table: Identification and particle … |
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Density is used to describe the compactness by which the individual soil particles have arranged or chained. From this, direct assumptions can be made concerning the soil strength, the additional compaction or displacement capability or the water … |
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Cohesive soils change their state or condition with water content. With a very high water content, cohesive soils are liquid and, with reduction of water content, change from a liquid to a plastic state, then to a stiff and finally into a very stiff (hard) condition, which means that the soil is less deformable and its strength increases. The transitions from one condition to the other have been defined by Atterberg [Atter11] and are called consistency … |
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The determination of the uniaxial compressive strength qu of soils, also known as cylinder compressive strength is carried out according to DIN 18136 [DIN18136:2003] on cylindrical or prismatic test bodies at constant compression velocity and with unhindered side expansion. The uniaxial compressive strength is also used in the description of the condition of cohesive soils (Abschnitt 4.3.1.5) [Kezdi68] [Lambe69]. A proposal in this respect for clays … |
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(Image: Soil element under shear loading [Schmi96]) Soil is a structure made up of a framework of solid particles with water and air-filled pores and is therefore sensitive to shear loads that are caused by shear stresses (Bild 4.3.1.7). The fact that a borehole, an excavated cavity in the subsoil, or the working face is stable without supports is a result of the shear strength τ of the subsoil. For instance, this shear strength is lowest for dry sand … |
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Nov 28, 2006 Trenchless Technology for Installation of Cables and Pipelines Mechanical fundamentals of soil and rock (geotechnical parameters) (Image: Flow chart for the identification and description of soils based on ISO 14688-1 [DINENISO14688a]) Soil is a mixture of minerals and/or organic components without mineral cohesion. Separation of the mineral components according to particle size by means of simple sieving or sedimentation process is possible. A further characteristic is the importance of point contacts among the mineral particles. Basically, soils consist of several phases:
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A large zone of rock (rock mass) is not a monolithic body but is more or less divided by discontinuities [DS853]. Their spatial arrangement in the rock mass is called the geologic structure (Tabelle 4.3.2.1) [DINENISO14689:2004]. (Table: Examples of terms which may be used in the description of rock mass structure to ISO14689 [DINENISO14689a])
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As the measured compressive strength of a body can vary depending on the standards of the testing, the determination of the uniaxial compressive strength (UCS) of rock material should be carried out in Germany on the basis of an uniaxial compression test in accordance with DIN 18316 [DIN18136:2003] and the recommendations No. 1 of the Deutsche Gesellschaft für Erd- und Grundbau (DGEG), now called the Deutsche Gesellschaft für Geotechnik (DGGT) [… |
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Nov 28, 2006 Trenchless Technology for Installation of Cables and Pipelines Mechanical fundamentals of soil and rock (geotechnical parameters) ISO 14689 [DINENISO14689:2004] defines rock as, "a naturally occurring assemblage of minerals, consolidated, cemented or otherwise bonded together, so as to form material of generally greater strength or rigidity than soils". Rock material, according to ISO 14689 [DINENISO14689:2004] is, "the intact rock within the framework of the discontinuities." There are intermediate stages between solid and loose sediments. When testing solid rock and rock bond … |
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Nov 28, 2006 Trenchless Technology for Installation of Cables and Pipelines Mechanical fundamentals of soil and rock (geotechnical parameters) According to DIN 1054 [DIN1054:2005] a soil is termed, "made when it has originated due to filling or hydraulic filling". This is divided into:
Embankments, railway banks, waste dumps (landfills) as well as most of the surface regions under … |
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