The Effect Of Steel Fibers On Self Compacting Concrete

Steel-reinforced concrete is a widely used structural material. The effectiveness of the steel reinforcement depends on the bond between the steel reinforcing bar and the concrete. Reinforced concrete is a composite material in which concrete 's relatively low tensile strength and ductility are counteracted by the inclusion of reinforcement having higher tensile strength and ductility. The reinforcement is usually, though not necessarily, steel reinforcing bars and is usually embedded passively in the concrete before it sets. Reinforcing schemes are generally designed to resist tensile stresses in particular regions of the concrete that might cause unacceptable cracking and

The definition of high strength changes over the years as concrete strength used in the field increases. Any construction activity requires several materials such as concrete, steel, brick, stone, glass, clay, mud, wood, and so on. However, the cement concrete remains the main construction material used in construction industries. For its suitability and adaptability with respect to the changing environment, the concrete must be such that it can conserve resources, protect the environment, economize and lead to proper utilization of energy. To achieve this, major emphasis must be laid on the use of wastes and byproducts in cement and concrete used for new constructions. The utilization of recycled aggregate

Ultra high performance concrete (UHPC) represents a major progress step over normal strength concrete (NSC) and high strength concrete (HSC), through the achievement of very high strength and very low permeability. Basically, the UHPC is a concrete with compressive strength ranging 120 to 400 MPa, this “ultra” high strength is achieved through different techniques including the use of improved materials, ultra-fine pozzolans (e.g. silica fume), low water-cement ratio, improved quality and higher dosage of superplasticizer, use of fibers (metallic or synthetic) to increase the energy absorption capacity and decrease brittleness, high cementitious materials content, longer mixing time and heat treatment [1]. UHPC tensile strength varies from 10 to 30 MPa; and the modulus of elasticity is in the range of 60 – 100 GPa [2].

The experimental program was included testing of lightweight concrete specimens under concentric axial load in both tension and compression, to obtain the actual stress-strain properties of the produced FBLWC. The concrete mix using foam balls previously designed at Ain Shams University were used. Different specimens' shapes like prisms, cylinders and cubes were tested to obtain the mechanical properties such as compressive strength, young modulus, tensile strength and flexural strength.

It results in rapid drying and requires increased curing to avoid increased plastic shrinkage cracking

To gain perspective on the behavior of lightweight concrete, available literature from the previous research work is reviewed and a review of the codes' and standards' requirements for this kind of concrete. This literature review provides an overview of previous work done on lightweight concrete. This chapter describes the nature of foamed balls concrete, its composition and properties and how it is used in civil engineering works. Because the properties of foamed concrete can vary widely, and it can be used in a wide variety of applications, it is important to define performance requirements for each case.

However, it is weak in tension as the cement holding the aggregate in place can crack, allowing the structure to fail. Reinforced concrete solves these problems by adding either meta reinforcing bars, steel fibers, glass fiber, or plastic fiber to carry tensile loads.

Abstract. Considerable network of transportation infrastructures such as highways, rails, and so forth are key providers to economic growth and productivity of countries. Consecutively, Reinforced Concrete (RC) is the predominant construction materials in constructing many of these infrastructures. RC is a unique construction material which allows flexible design layouts and offers safe bending and torsion to satisfy design requirements. However, being exposed to harsh environment and contamination such as salts, acid rain, distilled water, carbonation, sulphur and so on are the reasons for deterioration, thus significantly impacting the performance of these structures. Furthermore, the deterioration of these structures is not only a

In several recent studies autogenously crack-healing capacity of concrete has been recognized. Due to presence of secondary hydration of

ABSTRACT Self compacting concrete with suitable chemical admixtures like Super Plasticizer and viscosity modifying agent can be cured, alternatively by addition of an internal curing agent instead of using large quantities of water. Steel fibers on the other hand have been used in cement and concrete composites for more than four decades, most of the steel fibers were introduced in the market prior to 1980. This is in sharp contrast to the continuous progress and development in the cement matrix itself. The proposed aim of the experiment is to examine the behavior of self compacting self-cured concrete by changing the steel fiber content. The mix incorporated 40 % replacement of cement with fly ash. The compressive strength and flexural strength of concrete were compared with conventional concrete by adding 0.5%, 1% and 1.5% of steel fibers and a notable accession of 79% in flexural strength was observed without compromising with the compressive strength.

The report will mainly focus on the differences between reinforced, prestressed and partially stressed concrete. These concrete reinforcing methods differ in the period they have been used. Reinforced concrete was developed by a nursery owner in Paris in 1867, Joseph Monier, applying it to practical use for the first time (Salmon & Wang, 2007). Prestressed concrete’s discovery dates back to the late 1800’s. Freyssinet was one of the first engineers who used this method and realised that, for this method, high quality concrete with very high tensile steel wires, stressed as high as possible was needed (Chris Burgoyne, 2005).

Reinforced concrete is one of the most important available materials for construction in Egypt and all over the world. It is used in almost all structures as: buildings, shells, bridges, tunnels, tanks and retaining walls. Concrete is made by mixing binding materials as sand and gravel held together with a paste of cement and water. The used of admixture is to change certain characteristic of concrete such as workability, durability and time of hardening. Some of concrete advantages are its high compressive strength, its ability to cast in almost any desired shape, its economical and fire resistance. Low tensile strength, low ductility and cracking consider one of its disadvantages. Regardless of this disadvantages, concrete still the materials of choice in construction.

Concrete is known as a construction material which is widely used throughout the entire world. According to the research, concrete contains Portland cement and it is an essential element to concrete (Naik and Moriconi, 2010). This essential element is capable of releasing carbon dioxide significantly. As carbon dioxide is known to be a green house gas, hence it can be said that this type of concrete is damaging the environment. In order to save the environment a new technology is made by which eco – friendly concrete can be made. Such concretes are made of the concrete wastes that are known to be eco – friendly; therefore, the concrete is also eco – friendly. This type of concrete is also known as green

This experiment was therefore aimed at determining the ultimate compressive strength of different concrete samples after 14 days. Additionally, other properties of the concrete such as modulus of elasticity and Poisson ratio were also determined.

Concrete as is well known is a heterogeneous mix of cement, water and aggregates. The admixtures may be added in concrete in order to enhance some of the properties desired specially. In its simplest form, concrete is a mixture of paste and aggregates. Various materials are added such as fly ash, rice husk, and admixture to obtain concrete of desired property. The character of the concrete is determined by quality of the paste. The key to achieving a strong, durable concrete rests in the careful proportioning, mixing and compacting of the ingredients.