Soil compactionIn geotechnical engineering, soil compaction is the process in which stress applied to a soil causes densification as air is displaced from the pores between the soil grains. When stress is applied that causes densification due to water (or other liquid) being displaced from between the soil grains, then consolidation, not compaction, has occurred. Normally, compaction is the result of heavy machinery compressing the soil, but it can also occur due to the passage of, for example, animal feet.
Specific weightThe specific weight, also known as the unit weight, is the weight per unit volume of a material. A commonly used value is the specific weight of water on Earth at , which is . Often a source of confusion is that the terms specific gravity, and less often specific weight, are also used for relative density. A common symbol for specific weight is γ, the Greek letter Gamma. The specific weight, γ, of a material is defined as the product of its density, ρ, and the standard gravity, g: The density of the material is defined as mass per unit volume, typically measured in kg/m3.
Diaphragm (structural system)In structural engineering, a diaphragm is a structural element that transmits lateral loads to the vertical resisting elements of a structure (such as shear walls or frames). Diaphragms are typically horizontal but can be sloped in a gable roof on a wood structure or concrete ramp in a parking garage. The diaphragm forces tend to be transferred to the vertical resisting elements primarily through in-plane shear stress.
EcohydrologyEcohydrology (from Greek οἶκος, oikos, "house(hold)"; ὕδωρ, hydōr, "water"; and -λογία, -logia) is an interdisciplinary scientific field studying the interactions between water and ecological systems. It is considered a sub discipline of hydrology, with an ecological focus. These interactions may take place within water bodies, such as rivers and lakes, or on land, in forests, deserts, and other terrestrial ecosystems.
Rock mechanicsRock mechanics is a theoretical and applied science of the mechanical behavior of rocks and rock masses. Compared to geology, it is the branch of mechanics concerned with the response of rock and rock masses to the force fields of their physical environment. Rock mechanics is part of a much broader subject of geomechanics, which is concerned with the mechanical responses of all geological materials, including soils. Rock mechanics is concerned with the application of the principles of engineering mechanics to the design of structures built in or on rock.
CrusherA crusher is a machine designed to reduce large rocks into smaller rocks, gravel, sand or rock dust. Crushers may be used to reduce the size, or change the form, of waste materials so they can be more easily disposed of or recycled, or to reduce the size of a solid mix of raw materials (as in rock ore), so that pieces of different composition can be differentiated. Crushing is the process of transferring a force amplified by mechanical advantage through a material made of molecules that bond together more strongly, and resist deformation more, than those in the material being crushed do.
Slope stability analysisSlope stability analysis is a static or dynamic, analytical or empirical method to evaluate the stability of slopes of soil- and rock-fill dams, embankments, excavated slopes, and natural slopes in soil and rock. It is performed to assess the safe design of a human-made or natural slopes (e.g. embankments, road cuts, open-pit mining, excavations, landfills etc.) and the equilibrium conditions. Slope stability is the resistance of inclined surface to failure by sliding or collapsing.
Soil physicsSoil physics is the study of soil's physical properties and processes. It is applied to management and prediction under natural and managed ecosystems. Soil physics deals with the dynamics of physical soil components and their phases as solids, liquids, and gases. It draws on the principles of physics, physical chemistry, engineering, and meteorology. Soil physics applies these principles to address practical problems of agriculture, ecology, and engineering.
Concrete degradationConcrete degradation may have many different causes. Concrete is mostly damaged by the corrosion of reinforcement bars due to the carbonatation of hardened cement paste or chloride attack under wet conditions. Chemical damages are caused by the formation of expansive products produced by various chemical reactions, by aggressive chemical species present in groundwater and seawater (chlorides, sulfates, magnesium ions), or by microorganisms (bacteria, fungi...).
GabionA gabion (from Italian gabbione meaning "big cage"; from Italian gabbia and Latin cavea meaning "cage") is a cage, cylinder or box filled with rocks, concrete, or sometimes sand and soil for use in civil engineering, road building, military applications and landscaping. For erosion control, caged riprap is used. For dams or in foundation construction, cylindrical metal structures are used. In a military context, earth- or sand-filled gabions are used to protect sappers, infantry, and artillerymen from enemy fire.
