Flexural Strength of Concrete

Flexural Strength of Concrete

Flexural Strength Flexural strength is an indirect measure of the tensile strength of concrete. It is a measure of the maximum stress on the tension face of an unreinforced concrete beam or slab at the point of failure in bending. It is measured by loading 150 x 150-mm (or (100 x 100-mm) concrete beams with a span length …

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Effect of SCMs on Alkali-Silica Mitigation

ASR

Effect of SCMs on Alkali-Silica-Reaction Mitigation 1- Fly Ash the three characteristics of fly ash that determine its efficiency in preventing ASR are fineness, mineralogy, and chemistry. In general, the finer the fly ash, the more efficient it is in reducing ASR expansion. An ultra fine fly ash, with particle size around 3 μm, can …

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Reasons of Concrete Spalling

Reasons of Concrete Spalling

Concrete Spalling Currently, there are two mechanisms concerning the occurrence of spalling: 1- the pore pressure build up causes spalling in the cement matrix and 2- thermal and mechanical stresses. In 1997, Anderberg gave an account on spalling caused by vapour pressure. The mechanism is believed to be the same for both High Performance Concrete (HPC) …

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Corrosion of Embedded Metals in Concrete

Corrosion of Embedded Metals in Concrete Corrosion of reinforcing steel and other embedded metals is the leading cause of deterioration in concrete. When steel corrodes, the resulting rust occupies a greater volume than the steel. This expansion creates tensile stresses in the concrete, which can eventually cause cracking, delamination, and spalling (Figs. 1 and 2). …

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Origin and Classification of Aggregates

Origin and Classification of Aggregates Most of the properties of an aggregate derive from its parental rock chemical and mineral composition which affects strength, stiffness, density, pore structure and permeability. Rocks experience geothermal and weathering processes which can produce granular materials in the form of natural gravels and sands, these types of aggregates can be …

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Pervious Concrete

Pervious Concrete Pervious concrete is a type of concrete with a system of interconnected pores allowing water to rapidly drain through. Pervious concrete itself is made up of coarse aggregate that is coated by a thin layer of cement paste, holding the system together. While the compressive strength, void content, and permeability tend to vary …

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Characteristics of High volume Fly Ash Concrete

fly ash

Flyash Flyash is the by-product of the combustion of pulverized coal and is collected by mechanical and electrostatic separators from the fuel gases of power plants where coal is used as a fuel and the disposal of flyash is one of the major issues for environmentalists as dumping of flyash as a waste material may …

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Types of Chemical Admixtures

admixtures

Admixtures A material other than water, aggregates, or cement that is used as an ingredient of concrete or mortar to control setting and early hardening, workability, or to provide additional cementing properties. Why is admixture used? Over decades, attempts have been made to obtain concrete with certain desired characteristics such as high compressive strength, high …

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