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Characteristics of Green Concrete with Perlite as a Partial Replacement of Fine Aggregate
Published in P. C. Thomas, Vishal John Mathai, Geevarghese Titus, Emerging Technologies for Sustainability, 2020
Basil Baby, Serin Sara Roy, Emmanuel Jose
Perlite is a naturally occurring siliceous volcanic rock. It’s a kind of amorphous volcanic glass formed by the crystallization of obsidian which is formed form the periodic transformation of magma. Perlite has the peculiar feature, which is greatly expands when heated sufficiently, up to a range of 4 to 20 times of its original volume. The expanding properties upon heating were observed by Thomas Webb in 1824. This was the main reason for its thermal insulation and resisting capacity. Since the available natural resource for concreting is decreasing day by day, the introduction of more innovative and efficient construction materials like perlite will leads to the production of a sustainable green concrete. For standardizing and checking the strength parameters of the perlite added concrete, tests like compression strength test, split tensile strength and flexure strength should be conducted. The slump value which indicates the workability feature must be maintained in every trial taken for testing. Based on the results obtained, the Optimum dosage of perlite along with the replacement of fine aggregate must be determined from the peak values. M40 mix and targeted slump value of 75–100 (medium workability) were selected, based on the market study and their requirements in the construction process.
Rocks and rock minerals
Published in Ivan Gratchev, Rock Mechanics Through Project-Based Learning, 2019
During eruption (Figure 4.2a), gas bubbles in the molten lava become voids in the solidified form, producing light and porous volcanic rocks such as pumice and scoria (Figure 4.4). Volcanic glass (also known as obsidian) arises from the sudden cooling of lava droplets during flight.
Volcanoes and Their Products
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
Secondary minerals are common in volcanic rocks, because minerals that form at high temperature are typically unstable under Earth surface conditions. So, they may react to form any of the secondary minerals discussed in the previous chapter. Additionally, volcanic glass is unstable and will, over time, devitrify (become partially or wholly crystalline). Consequently, it is uncommon to find obsidian older than 10 or 20 million years. Figure 7.45 shows a pig carved out of snowflake obsidian. The white “snowflakes” are made of cristobalite (a polymorph of quartz) crystals that formed by devitrification of once homogeneous solid obsidian glass.
Formulation and use of manufactured soils: A major use for organic and inorganic wastes
Published in Critical Reviews in Environmental Science and Technology, 2022
R. J. Haynes, Y.-F. Zhou, X. Weng
There are a number of materials derived from volcanic activity that are used particularly in container mixes. These include (a) pumice which is a spongy, porous form of volcanic glass, (b) perlite which is an amorphous volcanic glass formed from hydration of obsidian which when crushed and heat-treated forms an expanded light-weight product and (c) tuff which is a type of igneous rock mined in quarries (Papadopoulos et al., 2008). Vermiculite is also commonly used in container mixes and consists of vermiculite 2:1 clay exfoliated by heating to 1000 °C. Rockwool is manufactured by melting basaltic rock with limestone and coke at high temperatures and spinning the melt into fibers. It is used in horticulture either as rigid slabs, blocks or cubes (especially for glasshouse vegetable production) and as granules for use as a component of container media (Bussell & McKennie, 2004).