Collaboratively inspect large-area sewer pipe networks using pipe robotic capsules

Ageing drinking water, stormwater and sewer pipe networks imply an increased degree of rehabilitation. The need for rehabilitation can be predicted using lifetime distribution functions together with current network age and material distribution. In Sweden, current age and material distribution is neither documented on a national level, nor for many water utilities on a local level. In this study, current network age and material distribution was provided through a questionnaire sent to Swedish water and wastewater utilities and the data provided were extrapolated to cover the whole of Sweden. The data were then combined with lifetime distribution functions to provide predictions. One limitation is that for newer materials the lifetime is still uncertain. Predictions were made for different scenarios to reflect local differences and the medium scenario shows that while the Swedish rehabilitation rate is stable, investments in monetary terms need to double in the next 60 years. The rehabilitation rate is also dependent on the extent to which the network is expanded. This method can be used to calculate national investment needs, and the results can also provide a basis for estimates for Swedish utilities with data scarcity.

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POINT CLOUD BASED VISUALIZATION SYSTEM OF SEWER PIPE NETWORKS – FOR REDUCING MAINTENANCE AND OPERATOIN COSTS –

Journal of Japan Society of Civil Engineers Ser F3 (Civil Engineering Informatics) ◽

10.2208/jscejcei.74.ii_71 ◽

2018 ◽

Vol 74 (2) ◽

pp. II_71-II_78

Author(s):

Eiji NAKAMURA ◽

Yoshiyuki YAMAMOTO

Keyword(s):

Point Cloud ◽

Sewer Pipe ◽

Visualization System ◽

Pipe Networks

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Assessing the impact of renewal scenarios on the global structural state of sewer pipe networks

Canadian Journal of Civil Engineering ◽

10.1139/cjce-2014-0037 ◽

2014 ◽

Vol 41 (8) ◽

pp. 761-768 ◽

Cited By ~ 2

Author(s):

Sophie Duchesne ◽

Kassandra Bouchard ◽

Babacar Toumbou ◽

Jean-Pierre Villeneuve

Keyword(s):

Structural State ◽

Sewer Pipe ◽

Pipe Networks ◽

The Impact

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Performance assessment of Swedish sewer pipe networks using pipe blockage and other associated performance indicators

H2Open Journal ◽

10.2166/h2oj.2020.027 ◽

2020 ◽

Vol 3 (1) ◽

pp. 46-57 ◽

Cited By ~ 1

Author(s):

E. Okwori ◽

M. Viklander ◽

A. Hedström

Keyword(s):

Performance Assessment ◽

Water Conservation ◽

Complex Nature ◽

Sewer Pipe ◽

Explanatory Factors ◽

Pipe Networks ◽

Using Data ◽

The Cost ◽

Levels Of Service ◽

Benchmarking System

Abstract Sewer pipe networks are expected to operate with minimal or no interruptions. The complex nature of randomly occurring failures in sewer networks arising from blockages significantly adds to the cost of operation and maintenance. Blockages are significant due to sewage backup or basements flooding, resulting from their occurrence. Therefore, continuous performance assessment of sewer pipe networks is necessary to ensure required levels of service at an acceptable cost. This study provides insight into the performance of the sewer pipe networks by assessing the proneness of the network to blockages. Furthermore it draws inferences at a holistic strategic level of influential explanatory factors of blockage proneness, using data available in the Swedish Water and Wastewater Association's benchmarking system. Results indicate that medium sized municipalities are prone to at least 30% more blockages per km per year compared to other municipalities. A hypothesis of explanatory factors includes reduced flow volumes and flow depth. Flow velocities below self-cleaning velocity in sewer pipe networks, encouraged by sluggishness of flow are responsible for increased possibility for sediment deposition and accumulation in sewers leading to blockages. This is also exacerbated by the deposition of non-disposables (wet wipes, baby diapers, hard paper, etc.), accumulation of fats, oils and grease in sewers and increased water conservation measures.

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Will greywater reuse really affect the sewer flow? Experience of a residential complex in Al Ain, UAE

Water Science & Technology Water Supply ◽

10.2166/ws.2016.131 ◽

2016 ◽

Vol 17 (1) ◽

pp. 246-258 ◽

Cited By ~ 3

Author(s):

R. K. Chowdhury ◽

M. A. Rajput

Keyword(s):

United Arab Emirates ◽

Water Distribution ◽

Research Question ◽

Flow Characteristics ◽

Water Distribution Network ◽

Design Flow ◽

Water Pipe ◽

Sewer Pipe ◽

Pipe Networks ◽

Al Ain

Reuse of recycled wastewater is one of the most feasible unconventional urban water sources in the United Arab Emirates (UAE). The extraction and reuse of greywater might affect the water and sewer pipe networks by changing flow characteristics. Therefore, the research question is how much greywater can be reused without affecting the existing water and sewer pipe networks? A residential complex located in Al Ain, UAE, was investigated in this regard. Water pipe network, water consumption and sewer flow data were collected and scenario modelling was conducted using the EPANET software. It was found that 100% capture and reuse of greywater has no impact on the upstream water distribution network, but reduces the recommended design flow in the downstream sewer network. The modelling results show that about 50% of generated greywater (about 95 litres per capita per day) can be harvested without affecting the upstream and downstream water and sewer flow characteristics, respectively.

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Application of multi-objective evolutionary algorithms for the rehabilitation of storm sewer pipe networks

Journal of Flood Risk Management ◽

10.1111/jfr3.12143 ◽

2015 ◽

Vol 10 (3) ◽

pp. 326-338 ◽

Cited By ~ 14

Author(s):

J. Yazdi ◽

A. Sadollah ◽

E.H. Lee ◽

D.G. Yoo ◽

J.H. Kim

Keyword(s):

Evolutionary Algorithms ◽

Sewer Pipe ◽

Multi Objective ◽

Pipe Networks ◽

Storm Sewer

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Convergent Beam Electron Diffraction

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100070072 ◽

1978 ◽

Vol 36 (3) ◽

pp. 304-315

Author(s):

G. Lehmpfuhl

Keyword(s):

Electron Diffraction ◽

Diffraction Pattern ◽

Crystal Surface ◽

Diffraction Spot ◽

Crystal Thickness ◽

Large Area ◽

Electron Microscopic ◽

Additional Information ◽

Microscopic Investigations

Introduction In electron microscopic investigations of crystalline specimens the direct observation of the electron diffraction pattern gives additional information about the specimen. The quality of this information depends on the quality of the crystals or the crystal area contributing to the diffraction pattern. By selected area diffraction in a conventional electron microscope, specimen areas as small as 1 µ in diameter can be investigated. It is well known that crystal areas of that size which must be thin enough (in the order of 1000 Å) for electron microscopic investigations are normally somewhat distorted by bending, or they are not homogeneous. Furthermore, the crystal surface is not well defined over such a large area. These are facts which cause reduction of information in the diffraction pattern. The intensity of a diffraction spot, for example, depends on the crystal thickness. If the thickness is not uniform over the investigated area, one observes an averaged intensity, so that the intensity distribution in the diffraction pattern cannot be used for an analysis unless additional information is available.

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TEM Study of a Tilt Boundary in Hot-Pressed Silicon

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100097454 ◽

1981 ◽

Vol 39 ◽

pp. 160-161

Author(s):

C. B. Carter ◽

J. Rose ◽

D. G. Ast

Keyword(s):

Electron Diffraction ◽

Imaging Technique ◽

Interface Structure ◽

Large Area ◽

Weak Beam ◽

Lattice Fringe ◽

Electron Diffraction Technique ◽

Tilt Boundaries ◽

Beam Technique ◽

Twist Boundaries

The hot-pressing technique which has been successfully used to manufacture twist boundaries in silicon has now been used to form tilt boundaries in this material. In the present study, weak-beam imaging, lattice-fringe imaging and electron diffraction techniques have been combined to identify different features of the interface structure. The weak-beam technique gives an overall picture of the geometry of the boundary and in particular allows steps in the plane of the boundary which are normal to the dislocation lines to be identified. It also allows pockets of amorphous SiO2 remaining in the interface to be recognized. The lattice-fringe imaging technique allows the boundary plane parallel to the dislocation to be identified. Finally the electron diffraction technique allows the periodic structure of the boundary to be evaluated over a large area - this is particularly valuable when the dislocations are closely spaced - and can also provide information on the structural width of the interface.

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P20 phosphor on polyimide as a large area high-resolution transmission screen for slow scan CCD systems

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100136477 ◽

1995 ◽

Vol 53 ◽

pp. 20-21

Author(s):

C. C. Ahn ◽

S. Karnes ◽

M. Lvovsky ◽

C. M. Garland ◽

H. A. Atwater ◽

...

Keyword(s):

Mechanical Stability ◽

High Energy ◽

Practical Implementation ◽

Line Pair ◽

Modulation Transfer ◽

Large Area ◽

Ccd Imaging ◽

Transmission Electron ◽

The One ◽

Beam Broadening

The bane of CCD imaging systems for transmission electron microscopy at intermediate and high voltages has been their relatively poor modulation transfer function (MTF), or line pair resolution. The problem originates primarily with the phosphor screen. On the one hand, screens should be thick so that as many incident electrons as possible are converted to photons, yielding a high detective quantum efficiency(DQE). The MTF diminishes as a function of scintillator thickness however, and to some extent as a function of fluorescence within the scintillator substrates. Fan has noted that the use of a thin layer of phosphor beneath a self supporting 2μ, thick Al substrate might provide the most appropriate compromise for high DQE and MTF in transmission electron microcscopes which operate at higher voltages. Monte Carlo simulations of high energy electron trajectories reveal that only little beam broadening occurs within this thickness of Al film. Consequently, the MTF is limited predominantly by broadening within the thin phosphor underlayer. There are difficulties however, in the practical implementation of this design, associated mostly with the mechanical stability of the Al support film.

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