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Fire Hazards of Materials and Their Control
Published in Peter M. Bochnak, Fire Loss Control, 2020
Tanks of an above-ground tank farm should be located on ground draining away from important facilities, which may require diverting walls. Where this is possible, a slope of not less than 1% away from the tank toward the drainage system should be provided, with termination of the drainage system in a safely located impounding area having a capacity of not less than the capacity of the largest tank served. In lieu of drainage for protection of exposed property or waterways, confinement of liquid around the tank should be by means of a dike having a volumetric capacity of not less than the greatest amount of liquid that can be releases from the largest tank within the diked area (assuming a full tank). Dikes may be of earth, steel, concrete, or solid masonry construction and of a liquid-tight design adequate to withstand the full hydrostatic head anticipated. To prevent entrapment of personnel, dike heights should be restricted to an average height of 6 ft above interior grade.
Canal embankment failure mechanism, breach parameters and outflow predictions
Published in Jean-Pierre Tournier, Tony Bennett, Johanne Bibeau, Sustainable and Safe Dams Around the World, 2019
H. Kheirkhah Gildeh, P. Hosseini, H. Zhang, M. Riaz, M. Acharya
Irrigation canals are often used in modern agricultural areas worldwide and have been used successfully in Canada as well. However, breaching of canal embankments is an old concern and still a number of events occur yearly causing both monetary and human losses. Major dike failures include but are not limited to Yangtze flood in China 1998, the Elbe flood in Germany 2002, the New Orleans flood in 2005, the Mississippi flood in 2008, the del Dique flood in Columbia 2010 (Figure 1) and the Queensland flood in Australia 2011. A dike failure can occur due to several reasons including extreme flood event, earthquake, soil settlements, piping, seepage, etc. In the particular case of earth dikes, the most common failure cases and modes are (Singh 1996): (1) overtopping caused by extreme floods; (2) structural failure due to internal erosion (piping); (3) structural failure due to shear slide; (4) structural failure due to foundation problems; (5) failure due to natural or induced seismicity. Causes (1) and (2) are related to hydraulic failure which are the focus of this study, while causes (3) to (5) are mainly dominated by geotechnical processes and thus are referred to as “geotechnical failures”. The governing mechanisms of dike failures were also described by the University pf California in 2006 (Figure 2).
Plutonic Rocks
Published in Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough, Earth Materials, 2019
Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough
Dikes are nonconformable sheet-like intrusions that may cut across sedimentary or other layering or through a massive rock that has no layering (Figs. 6.7c, d). Dikes generally form from magma intruding along steep or near-vertical fractures, but tectonic forces may later rotate them to different orientations. The term vein (Fig. 6.7f) is used by some as a synonym for dike, but most geologists reserve the word vein for small, irregular and branching, and sometimes discontinuous, intrusions. In contrast, dikes are larger, sometime huge, and have uniform thickness and parallel sides. Dikes and sills range from felsic to mafic compositions, but around the world mafic dikes are the most common. A special kind of dike, called a feeder dike, carries magma to the surface, producing volcanic eruptions. Non-feeder dikes stall before they get there. When one observes a dike in outcrop, it is often difficult to determine whether it was a feeder dike if all overlying volcanics have been eroded. However, remnants of feeder dikes are sometimes preserved as volcanic necks (see Fig. 6.6), frozen magmas that once fed a volcano but now have become exposed by the removal of surrounding country rocks.
Effects of flood wave shape on probabilistic slope stability of dikes under transient groundwater conditions
Published in Georisk: Assessment and Management of Risk for Engineered Systems and Geohazards, 2023
Teun van Woerkom, Mark van der Krogt, Marc F. P. Bierkens
Dikes (i.e. earthen flood defenses) form an extensive network along many major rivers around the world aimed at mitigating flood risk and prevent flooding. Climate change may increase the risk of a society to flooding (Middelkoop et al. 2001), for example through expedited snow melt or an increase in extreme precipitation events in the upstream drainage area (IPCC 2022). Under current and future climatic conditions, levee breaches can be caused by for example dike overtopping, slope instability due to seepage or under-seepage. Slope instability during river floods is one of the major failure mechanisms of river dikes and tends to occur rapidly, leaving little room for mitigation. Slope instability of these river dikes is associated with large uncertainties, mainly relating to soil properties (van der Krogt, Schweckendiek, and Kok 2019) and groundwater pore pressures (van Woerkom et al. 2021). The pore water pressure (pressure heads) in the dike and subsoil is also one of the main drivers leading to slope instability during floods.
Geotechnical considerations for the concept of coastal reservoir at Mangaluru to impound the flood waters of Netravati River
Published in Marine Georesources & Geotechnology, 2019
C. R. Parthasarathy, T. G. Sitharam, S. Kolathayar
A sea dike is an embankment widely used to protect low-lying areas against inundation and acts as a backwater to prevent erosion of the coast and encroachment of the sea. The purpose of a sea dike is to protect areas of human habitation like towns & villages and conservation and leisure activities from the action of tides and waves. Storage of the abundant monsoon water can be done close to the coast using coastal reservoirs, which otherwise runs off to the ocean. Coastal reservoirs are bounded by impermeable sea dikes at one side and the coast on the other side (Yang 2015). These sea dikes with suitable modifications can be used for creating coastal reservoirs within the shallow waters of the coast. Sea dike is a static feature and it will conflict with the dynamic nature of the coast and impede the exchange of sediment and salt water between land and sea at the mouth of river. Sea dikes are classified as a hard engineering shore-based structure used to provide protection and to lessen coastal erosion. Sea dikes may also be constructed from a variety of materials, most commonly: geosynthetic tubes, geocells, reinforced concrete, boulders, steel, or gabions. Sea dikes are primarily used at exposed coasts, but they are also used at moderately exposed coasts, and in this study, use of sea dikes is presented for the separation of ocean salt water from the flood water from rivers stored in coastal reservoirs (Sitharam 2017).
Numerical modelling of simultaneous overtopping and seepage flows with application to dike breaching
Published in Journal of Hydraulic Research, 2019
Shinichiro Onda, Takashi Hosoda, Nenad M. Jaćimović, Ichiro Kimura
Dike breaching due to overtopping can cause severe damage during flood events. Therefore, for risk assessment purposes, it is of great importance to understand the mechanism of dike failure and predict the breaching process accurately. Dike failure is mainly explained by two mechanisms: one is the surface erosion due to shear stress of overtopping flow, and the second is the soil deformation by reduction of effective stresses due to seepage flow. The local flow characteristics along the dike surface are extremely complex, as flow direction and bottom pressure along the slope change abruptly from the crest to the dike toe. In addition, seepage flow in the embankment strongly affects stability of the whole structure. Consequently, in order to predict flow conditions and sediment transport around a dike accurately, the model has to include temporal changes of water surface, seepage flow through the dike body and the corresponding bed deformation process during the dike breaching.