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Nov 03, 2004 |
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According to the definition in ATV-A 127E [ATVA127a], taking into account EN 1610 [DINEN1610:1997] and EN 1295 [DINEN1295-1], one distinguishes flexible sewage pipes from rigid pipes as follows: "Rigid pipes are those in which the loading does not produce any appreciable deformation and therefore has no effect on pressure distribution." "Flexible pipes are those whose deformation considerably influences the loading and pressure distribution as the … |
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The possible consequences of damage of deformation are, according to [ATVM143-1:1989] :
Each deviation from the ideal hydraulic … |
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Nov 03, 2004 |
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Feb 16, 2011 Of the main forms of cracks mentioned, the ones that occur most often in rigid piping are longitudinal cracks (Bild 2.8.1.1).
In most cases they occur in the quarter points of the pipe (Bild 2.8.1.1). The crown and invert cracks open on the inside, the side cracks on the outside (Bild 2.8.1.1) |
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Feb 16, 2011 Besides the causes of damage already mentioned above, longitudinal cracks occur specially through [ATVM143-1:1989] :
With rigid piping, longitudinal cracks occur due to exceeding the annular bending strength, e.g. with the lay of the pipe. In addition, cracks can originate as a result of position deviation caused by changes of the bedding … |
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Nov 03, 2004 |
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Lateral cracks mostly encompass the whole circumference of the pipe (Bild 2.8.2.1) (Bild 2.8.2.1).
Predestined places are the middle of the pipe (Bild 2.8.2.1), the pipe joints or connections to manholes or structures or transfer to a direct structure. (Image: Formation of circumferential cracks due to incorrect … |
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Nov 03, 2004 |
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Feb 16, 2011 Besides the longitudinal and lateral cracks, which have a fixed course of the crack, there are cracks in sewers that either originate at a point and radiate outwards (Bild 2.8.3.1) or cracks with a completely irregular course (Bild 2.8.3.1) (Bild 2.8.3.1).
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Nov 03, 2004 |
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Pipe break is understood to be the missing of more or less large pieces of the pipe walling (Bild 2.8.4.1) (Bild 2.8.4.1) (Bild 2.8.4.1) (Bild 2.8.4.1).
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Nov 03, 2004 |
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Collapse is understood to be the complete loss of carrying capacity connected with the destruction of the respective component (Bild 2.8.5.1) (Bild 2.8.5.1) (Bild 2.8.5.1).
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Nov 03, 2004 |
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Feb 16, 2011 The consequences of damage when cracks occur in sewers are substantially influenced by
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Nov 03, 2004 The "cracks" type of damage occurs primarily in rigid piping, whereby distinction is made between three main forms which can be the precursors for the pipe break and, finally, for the collapse of the sewer [ATVM143-1:1989].
The causes of cracks are closely connected with their type, whereby the form of a crack, its dimension and its course allows … |
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Inspection, in accordance with ATV-M 143E Part 1 [ATVM143-1:1989] is understood to be: Measures for Determining and Evaluating the Actual Condition Inspection plays a central role in rehabilitation and maintenance. Its task is the preparation of data and information on the actual condition and the current wear reserve of the respective unit under review or on points of damage to it, and to recognise their causes at an early stage in order that rehabilitation … |
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The inspection of structures is carried out either as planned measures, i.e. regularly or at regularly timed intervals (Inspection strategy) or only when, in the course of operation, obvious changes can be seen (Failure strategy). In addition, inspections are carried out in order to investigate possibilities for changes of utilisation of a structure. Contrary to the practice up to the present, which preferred the failure strategy, the inspection strategy … |
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Feb 16, 2011 (Image: Manhole top raised above street level as a result of settling) The aboveground walk-through and examination of the street and ground surface of the sewer section in the catchment area represents the simplest form of inspection. In this way, possible effects of damage in the sewers, e.g. in the region of the manholes (Abschnitt 1.8) and the street surface can be recognised and taken into consideration in the planning and execution of internal … |
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Nov 19, 2004 The seismic method is by far the most important and widely used method of exploratory geophysics with which deposits (oil, gas, and coal) are explored and this method also provides the engineering and environmental fields with important structural information. In the seismic method, the information is carried by elastic waves and wave fields, which can be processed to provide figures of the underground. This enables a direct view of its complex structure … |
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Nov 19, 2004 In the seismic reflection method, the reflected waves that were created at the surface and reflected by the border surfaces are registered (relative to the target depth) within short distances from the source. The very comprehensive data material from the multi-channel telemetric apparatus can be processed and depicted with the aid of special computer methods in such a way that an underground structure is shown that can be directly interpreted. In … |
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Nov 19, 2004 In the seismic refraction method, the waves are registered at greater distances from the source (relative to the target depth). This means that, besides the reflexions from the underground, waves are also received that have used the quickest path between source and receivers and thus provide the first application in the seismic signals. Computer programs have been developed very recently to process these wave fields in such a way show that direct … |
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Nov 19, 2004
Seismic tomography provides a laminar figure of the distribution of the compression wave velocity and the amplitude damping and thus indirectly a depiction of the distribution of certain material characteristics. A pre-condition of their application … |
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