— Volcanic ash can reduce the embodied energy of cement production by up to 16 percent, according to a study by MIT. The team also found that the optimal amount of ash for concrete depends on the …
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— The methods of evaluating volcanic ash activity mainly include direct method and indirect method [11].The direct method is to determine residual CH of the reaction system of pozzolanic material and portland cement hydration product CH solution in each age solution or in acid-base solution.
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Numerous archaeological and mineralogical studies indicate ancient Romans may have learned to harness volcanic ash for the earliest known concrete recipe by watching it harden when mixed naturally ...
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— His group is partnering with the government of Saint Vincent on a pilot project to manufacture concrete blocks made partly from volcanic ash. Typical concrete is made using cement in a process that generates a lot of carbon pollution. The concrete that Stofleth's group developed requires 15% less cement. And it's cheaper because it uses ...
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MIT engineers show that replacing cement with volcanic ash can reduce the energy and carbon footprint of concrete structures. They map out the tradeoff between strength and embodied energy of concrete mixtures …
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Upcycled volcanic ash concrete solves the twofold problem of making reconstruction efforts more affordable, while also drastically reducing carbon emissions during the process, by taking a page out of the ancient Roman concrete manual. Long before the industrial revolution and the invention of Portland cement, Romans collected and used volcanic ...
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— Numerous archaeological and mineralogical studies indicate ancient Romans may have learned to harness volcanic ash for the earliest known concrete recipe by watching it harden when mixed naturally with water. "Today we have the opportunity to observe cementation with the lens of 21st-century technology and knowledge of …
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— This is of great importance in mass concrete construction, for which Portland volcanic ash cement (PVAC) or Portland volcanic pumice cement (PVPC) can be mostly used, besides other general use. 3.2. Effect on strength. The variation in the compressive strength is shown in Fig. 2. The compressive strength is found to decrease with an …
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— Modern cement mixtures tend to erode, particularly in the presence of seawater, but the Roman recipe of volcanic ash, lime, seawater and a mineral called aluminium tobermorite actually reinforces ...
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The "natural concrete" at the Campi Flegrei volcano is similar to Roman concrete, a legendary compound invented by the Romans and used to construct the Pantheon, the Coliseum, and ancient shipping ports throughout the Mediterranean. ... As a result of this practice, volcanic ash from Campi Flegrei–and the use of Roman concrete–spread ...
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— Researchers conducted their research by studying concrete cores from the ancient Roman pier, Portus Cosanus in the Orbetello region of Italy. They discovered that Roman engineers used a mix of volcanic ash, seawater and lime, which set off a chemical reaction that increased cohesion with exposure to seawater, even after the concrete had …
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— A research team from the Universitat Politècnica de València (UPV), part of the Institute of Concrete Science and Technology (ICITECH), is studying various samples of volcanic ash for the manufacture of …
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— This concrete was typically composed of volcanic tuff and other coarse aggregates (caementa), and bound by a mortar based on lime and pozzolanic materials such as volcanic ash (pulvis), the detailed …
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— Explosive volcanic eruptions can produce vast amounts of volcanic ash made up mainly of fragments of magmatic glass, country rock and minerals < 2 mm in size. Ash particles forming from magma fragmentation are generated by several processes when brittle response accommodates (local) deformation stress that exceeds the capability of …
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— Review of 189 articles on the utilization of volcanic pumice powder ash to produce green concrete. • The physical and chemical properties of volcanic pumice powder ash. • Understanding of the effect of VPPA on microstructure, fresh, hardened and durability properties of green concrete. • Discussion on relationships between various ...
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— The problem of reinforcement corrosion in volcanic ash based blended concrete is studied in [26], while in [27] the performance of volcanic ash blended cement concrete in mixed sulfate environment is treated. The study of durability performance of volcanic ashes concrete can also be found in [28].
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— In this study, volcanic ash-based geopolymer cement (VA-GPC) suitable for ambient-curing, has been synthesized by partially replacing the aluminosilicate material with 10 wt% fused alkali-bauxite (faBX) admixture incorporated to enhance geopolymeric reactivity of the former. A mixture of sodium hydroxide and sodium silicate solution, was …
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— They found that the 7 days-splitting tensile strength of concrete samples containing volcanic ash was lower than that of control samples made of cement only by 92.3 %, 80.8 %, and 76.2 %, for volcanic ash powder …
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— Influence of volcanic ash on the properties of concrete. 4.1. Compressive strength. Hossain and Lachemi (2004) reported the results of residual compressive …
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— The performance of volcanic ash concrete (VAC) mixtures was evaluated by conducting comprehensive series of tests on fresh and hardened properties as well as durability. The fresh and hardened properties of the concrete were assessed by slump, air content, and compressive strength, while durability characteristics were investigated by …
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— In the last quarter of 2021, there was a very significant eruption of the Cumbre Vieja volcano on the island of La Palma, belonging to the Canary Islands, Spain. It generated a large amount of pyroclastic …
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— The Romans already knew about the characteristics of volcanic ash, which they mixed with other materials to build walls. Scientists analyzing the composition of ancient Roman sea walls, which have withstood the test of time, have detected a strengthening substance called aluminium tobermorite, which crystallized when the ash …
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— Volcanic ash has several sustainable advantages as an additive in manufacturing concrete: The rocky material, which lies in ample supply around active and inactive volcanoes around the world, is naturally available; it is typically considered a waste material, as people typically do not use it for any widespread purpose; some volcanic …
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— This study investigates the effect of partial replacement of cement with volcanic ash (VA) on the compressive strength of laterized concrete. A total of 192 cubes of 150mm dimensions were cast and ...
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— Many scientists have pointed to the practice of including volcanic ash in the concrete mix, ... the key ingredient is the specific blend of limestone and volcanic ash used in the mortar, ...
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— Slump test and compacted factor test was carried out to check the effect of volcanic ash on the workability of fresh concrete. Volcanic ash partially replace cement in the order of 0%, 5%, 7.5% ...
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— Applying this knowledge toward modern cement production, they hope to improve the material's environmental impact. ... pozzolanic material such as volcanic ash from the area of Pozzuoli, on the Bay of Naples. This specific kind of ash was even shipped all across the vast Roman empire to be used in construction, and was described as a …
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PDF | On Mar 28, 2020, Agboola Shamsudeen Abdulazeez and others published Strength Performance of Concrete Produced with Volcanic Ash as Partial Replacement of Cement | Find, read and cite all the ...
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— Descriptions of volcanic ash have survived from ancient times. First Vitruvius, an engineer for the Emperor Augustus, and later Pliny the Elder recorded that the best maritime concrete was made with ash from volcanic regions of the Gulf of Naples (Pliny died in the eruption of Mt. Vesuvius that buried Pompeii), especially from sites near …
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— Instead of Portland cement, the Roman concrete used a mix of volcanic ash and lime to bind rock fragments. The Roman philosopher Pliny the Elder, described underwater concrete structures that ...
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