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Ferrocement or ferro-cement [1] is a system of construction using reinforced mortar [2] or plaster (lime or cement, sand, and water) applied over an "armature" of metal mesh, woven, expanded metal, or metal-fibers, and closely spaced thin steel rods such as rebar. The metal commonly used is iron or some type of steel, and the mesh is made with ...
Artificial light at night is one of the most obvious physical changes that humans have made to the biosphere, and is the easiest form of pollution to observe from space. [298] The main environmental impacts of artificial light are due to light's use as an information source (rather than an energy source).
As human technology becomes more evolved, such as that required to launch objects into orbit or to cause deforestation, the impact of human activities on the environment potentially increases. The anthroposphere is the youngest of all the Earth's spheres, yet has made an enormous impact on the Earth and its systems in a very short time.
Anthropic rock is rock that is made, modified and moved by humans.Concrete is the most widely known example of this. [1] The new category has been proposed to recognise that human-made rocks are likely to last for long periods of Earth's future geological time, and will be important in humanity's long-term future.
Polymer cements are made from organic chemicals that polymerise. Producers often use thermoset materials. While they are often significantly more expensive, they can give a water proof material that has useful tensile strength. Sorel cement is a hard, durable cement made by combining magnesium oxide and a magnesium chloride solution
Iron exists in a range of oxidation states from -2 to +7; however, on Earth it is predominantly in its +2 or +3 redox state and is a primary redox-active metal on Earth. [13] The cycling of iron between its +2 and +3 oxidation states is referred to as the iron cycle.
For example, a land on a major Project is marked as glacier on contract drawings. It was so hard that it had to be detonated. The contractor claimed that the soil was cemented during excavation as it was formed due to the clay matrix as well as the gravel. The owner concluded that this was due to the weathering of the pebbles.
Archimedes is said to have remarked about the lever: "Give me a place to stand on, and I will move the Earth." The recorded history of structural engineering starts with the ancient Egyptians. In the 27th century BC, Imhotep was the first structural engineer known by name and constructed the first known step pyramid in Egypt.