Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: colemanite waste

Sortuj według:

Ogranicz wyniki do:

Investigation of the effects of colemanite and colemanite concentrator wastes on the rheological and hardened properties of self-compacting concrete

Şeker Oğuz, Durgun Muhammed Yasin

Archives of Civil and Mechanical Engineering

2023

Vol. 23, no. 1

art. no. e50, 2023

In this study, the use of colemanite (C) and colemanite concentrator wastes (CW) in self-compacting concrete (SCC) mixtures was investigated. It is known that additives containing boron minerals have a retarding effect on cement hydration. From this viewpoint, boron minerals containing various concentrations of C and CW were used and their effects on fresh concrete properties were investigated. In this context, single point tests and rheometer tests were applied. In addition, the setting times and unit weights of the samples were measured, and the compressive strengths at 7, 28 and 90 days were determined. The hydration developments of the samples were investigated by TGA and SEM investigations. The use of C and CW generally negatively affected the compressive strength, while the use of 1% C provided a slightly higher strength than the reference at the end of 90 days. The degree of hydration data obtained using TGA and the microstructural investigations via SEM supported these results. As a result of fresh state tests, it has been observed that the use of C improves and maintains the fresh properties and rheological parameters of self-compacting concrete, while the use of CW generally had the opposite effect. It is thought that this is due to the negative effect of the clay minerals in CW's composition and the fact that the B2O3amount in its content is less when compared to the C.

Obtaining lightweight concrete using colemanite waste and acidic pumice

Erdogan Y., Yasari E., Gamage Ranjith P.

Physicochemical Problems of Mineral Processing

2016

Vol. 52, iss. 1

35--43

This paper presents some results of ongoing laboratory work to design a lightweight concrete using colemanite waste and pumice. Hisarcik and Espey colemanite wastes, acidic pumice aggregate as well as normal Portland cement were used to produce lightweight concrete with economic and environmental advantages. Two different groups and twenty different prescriptions were tried to produce lightweight concrete. The effect of colemanite waste on workability and strength of lightweight concrete were analysed by fresh and hardened concrete tests. The properties of materials examined include slump, air content, density and uniaxial compressive strength of the mortar. The results obtained were compared with control concrete properties and Turkish standard values. The examined tests results showed that lightweight concrete can be produced by the use of acidic pumice aggregate and colemanite waste. Furthermore, the colemanite waste can be used as cement additives and can reduce the cost and environmental pollution with using natural stone aggregate.