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Flexible Debris-resisting Barrier
A flexible debris-resisting barrier is a structure used to mitigate debris flows or to contain flow-entrained woods.{{Cite journal, last1=Song, first1=D., last2=Choi, first2=C. E., last3=Ng, first3=C. W. W., last4=Zhou, first4=G. G. D., date=2018-01-01, title=Geophysical flows impacting a flexible barrier: effects of solid-fluid interaction, url=https://doi.org/10.1007/s10346-017-0856-1, journal=Landslides, language=en, volume=15, issue=1, pages=99–110, doi=10.1007/s10346-017-0856-1, s2cid=3527695, issn=1612-5118 These structures mainly consist of interconnected metallic components (cables, posts, shackles...). Flexible debris-resisting barrier are derived from rockfall barriers and were first proposed in the middle of the 1990s in the USA. In torrents, flexible debris-resisting barrier constitute a sound alternative to check dams for containing debris flows. The main components of flexible debris-resisting barriers are: * An interception structure, made up of a principal net ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Debris Flow
Debris flows are geological phenomena in which water-laden masses of soil and fragmented Rock (geology), rock rush down mountainsides, funnel into stream channels, entrain objects in their paths, and form thick, muddy deposits on valley floors. They generally have bulk density, bulk densities comparable to those of rock avalanches and other types of landslide classification, landslides (roughly 2000 kilograms per cubic meter), but owing to widespread sediment liquefaction caused by high pore pressure, pore-fluid pressures, they can flow almost as fluidly as water. Debris flows descending steep channels commonly attain speeds that surpass 10 m/s (36 km/h), although some large flows can reach speeds that are much greater. Debris flows with volumes ranging up to about 100,000 cubic meters occur frequently in mountainous regions worldwide. The largest prehistoric flows have had volumes exceeding 1 billion cubic meters (i.e., 1 cubic kilometer). As a result of their hig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dissipation
In thermodynamics, dissipation is the result of an irreversible process that takes place in homogeneous thermodynamic systems. In a dissipative process, energy (internal, bulk flow kinetic, or system potential) transforms from an initial form to a final form, where the capacity of the final form to do thermodynamic work is less than that of the initial form. For example, heat transfer is dissipative because it is a transfer of internal energy from a hotter body to a colder one. Following the second law of thermodynamics, the entropy varies with temperature (reduces the capacity of the combination of the two bodies to do work), but never decreases in an isolated system. These processes produce entropy at a certain rate. The entropy production rate times ambient temperature gives the dissipated power. Important examples of irreversible processes are: heat flow through a thermal resistance, fluid flow through a flow resistance, diffusion (mixing), chemical reactions, and elec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Foundation (engineering)
In engineering, a foundation is the element of a structure which connects it to the ground, transferring loads from the structure to the ground. Foundations are generally considered either shallow or deep. Foundation engineering is the application of soil mechanics and rock mechanics (geotechnical engineering Geotechnical engineering is the branch of civil engineering concerned with the engineering behavior of earth materials. It uses the principles of soil mechanics and rock mechanics for the solution of its respective engineering problems. It a ...) in the design of foundation elements of structures. Purpose Foundations provide the structure's stability from the ground: * To distribute the weight of the structure over a large area in order to avoid overloading the underlying soil (possibly causing unequal settlement). * To anchor the structure against natural forces including earthquakes, floods, droughts, frost heaves, tornadoes and wind. * To provide a level su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Debris Flow
Debris flows are geological phenomena in which water-laden masses of soil and fragmented Rock (geology), rock rush down mountainsides, funnel into stream channels, entrain objects in their paths, and form thick, muddy deposits on valley floors. They generally have bulk density, bulk densities comparable to those of rock avalanches and other types of landslide classification, landslides (roughly 2000 kilograms per cubic meter), but owing to widespread sediment liquefaction caused by high pore pressure, pore-fluid pressures, they can flow almost as fluidly as water. Debris flows descending steep channels commonly attain speeds that surpass 10 m/s (36 km/h), although some large flows can reach speeds that are much greater. Debris flows with volumes ranging up to about 100,000 cubic meters occur frequently in mountainous regions worldwide. The largest prehistoric flows have had volumes exceeding 1 billion cubic meters (i.e., 1 cubic kilometer). As a result of their hig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Check Dam
A steel check dam A check dam is a small, sometimes temporary, dam constructed across a swale, drainage ditch, or waterway to counteract erosion by reducing water flow velocity. Check dams themselves are not a type of new technology; rather, they are an ancient technique dating from the second century A.D. Check dams are typically, though not always, implemented in a system of several dams situated at regular intervals across the area of interest. Function A check dam placed in the ditch, swale, or channel interrupts the flow of water and flattens the gradient of the channel, thereby reducing the velocity. In turn, this obstruction induces infiltration and reduces eroding. They can be used not only to slow flow velocity but also to distribute flows across a swale to avoid preferential paths and guide flows toward vegetation. Although some sedimentation may result behind the dam, check dams do not primarily function as sediment-trapping devices. For instance, on the Gra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rockfall Barrier
A rockfall barrier is a structure built to intercept rockfall, most often made from metallic components and consisting of an interception structure hanged on post-supported cables. Barriers are passive rockfall mitigation structures adapted for rock block kinetic energies up to 8 megajoules. Alternatively, these structures are also referred to as fences, catch fences, rock mesh, net fences.... History In the 1960s, the Washington State Department of Transportation conducted the very first experiments for evaluating the efficiency of barriers in arresting rock blocks. A so-called 'chain link fence attenuator' was exposed to impacts by blocks freely rolling down a slope for evaluating its efficiency. These experiments were followed by some others till the end of the 1990s. Progressively, the testing technique was improved using zip-lines to convey the rock block to the barrier. Testing real-scale structures is now very common and part of the design process. The very first use ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
