AIM: The aim of this topic is to define fiber reinforced concrete and its application, it important properties as well as it superior resistance to cracking. As a result of the ability of fiber to arrest cracks, the composites of fiber possesses an increased in tensile strength both at the first crack and at ultimate, especially under flexural loading, and the fibers can still hold the matrix together even after a lot of cracking.
Introduction
Concrete is a structural material that is weak in tension and they also have brittle properties with a low tensile strength and strain capacity. Fiber reinforced concrete is known as one of the fastest segments in concrete which contain fibrous materials which increase the structural integrity. Fiber reinforced concrete can also be defined as a composite materials which is compose of aggregate, cement and discrete discontinuous fibers. Fibers include natural fibers, glass fibers, synthetic fibers and steel fibers. Fiber is developed recently in the early sixties and when it is added to concrete makes it to be consistent and isotropic in nature. The mode of failure of fiber reinforced concrete is either by bond failure between fiber and matrix or failure of the materials.
The application area of fiber reinforced concrete is an old form of method which helps to improve the characteristics of construction materials. The recent applications include the addition of horse hair to reinforce plaster, asbestos to reinforce pottery and straw to mud bricks.
The role of fibers in concrete is to bridge across the cracks that develop some post cracking ductility and to increase it toughness and types of loading. The uses of reinforced concrete help to increase the strength and ductility but it req...
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...forced concrete beams up to 100 percent.
Column: The use of fibers help in reducing the types of explosives failure for columns and an increase of fiber content slightly increases the ductility of axially loaded strength.
Applications of Fiber Reinforced Concrete: The application of fibers in concrete industries depends on the designer and the builder. The main area where fiber reinforced concrete are applied is as follows:
Runway, Aircraft Parking, and pavements
Tunnel Lining and Slope Stabilization.
Blast Resistant Structures.
Thin Shell, Walls, Pipes and Manholes.
Dams and Hydraulics Structures
Conclusions: From my understanding, it shows that Fiber Reinforced Concrete is a promising material to be used because of it good properties, no workability problem , it helps to control cracks in concrete and it is long lasting in concrete structures.
Most people may not realise but concrete plays a vital part in our lives daily. It shapes and creates the built environment in which we are surrounded by, such as schools, bridges, roads, housing, hospitals, dams and so much mores. Concrete is the most used man made material in the world, averaging around 3 tonnes annually for each person. In comparison with other building materials such as wood, steel, plastic and aluminium, over twice as much concrete is used globally than any of these materials. It is the material choice of most purposes due to its strength, durability, thermal mass and its cost.
There have been many means and methods in the past decade, fostered to ensure that the construction of buildings, complexes and many enormous structures are made with energy saving measures such as heat dispersal during the summer, and to also ensure the promotion of environmental sustainability such as the control of carbon emissions and greenhouse gases. And by the use of complex and highly innovative building materials like carbon fiber, such feet can be achieved.
It is a versatile modern industrial material made of Silica in the form of numerous extremely fine filaments. These fibers might be finer than human hair many times and seem in appearance and feel as silk. It is a light weight material and very strong with favorable bulk strength compared with metals and it can be easily formed by means of molding processes. GF is the most prevail fiber reinforcement that used in construction and among the most adaptable industrial materials. They exhibit different useful properties such as transparency, hardness, resistance to chemical attack, inertness, and stability, as well as desirable fiber properties such as strength, stiffness, and flexibility.
In this paper we have studied compressive strength of concrete by replacing natural aggregate with recycled aggregate by 25%, 50% and 75%.This mixture formed in the sample of cubes of dimension 150x150x150mm3.
3) Super workable concretes have the ability to fill the heavily reinforced sections without internal or external vibration, without segregation and without developing large sized voids
[20] BS Part 116: 1983. Testing Concrete and determination of compressive strength. British Standards Institution ;
Aggregate: in cement concrete to gain good quality aggregates are used in two groups. Sand and coarse
Concrete is a composite material used widely in the construction industry. Concrete is basically a mixture of cement, water, aggregates and admixture (sometimes). Cement is a fine gray powder that consists of oxidizes calcium, silicon and aluminum. The aggregate used is normally gravel, crushed stone or sand. Admixture is a solid or liquid substance that gives a certain characteristics of the concrete. The cement reacts with water chemically and binds the aggregates together through a process called hydration during hardening or curing of concrete. It means that water helps in the hardening of the concrete while the cement bind the aggregate and also react with water to form a solid mass.
In a traditional way, a concrete mix is designed based on the code requirements and recommendations which uses the empirical values obtained from previous experiences. Compressive strength of concrete is determined by conducting standard uniaxial compression test on standard cylindrical sample specimens of ages 7 & 28 days, following the standard procedure and test values are reported in accordance with ASTM and ACI standards . If the strength value obtained from the test is less than the required strength after 28 days from date of placing of concrete, the entire process of concrete mix design has to be repeated until the required strength value is achieved, which is time consuming and costly. Numerous test samples with different mix ingredient proportions have to be created to achieve the required strength and is an iterative process. So, every mix designer wants a tool or methodology to predict the compressive strength of concrete required at the time of design, before placing the concrete.
The continuous strain, which the concrete undergoes due to application of external loads is called……………………………………….
...nd Calderwood 1978; Suaris and Shah 1984), because it requires higher energy to split the fibers from the concrete.
(Engg, 2013), investigated the structural properties of foamed concrete with and without pulverized bone. The tensile strength was evaluated by subjecting 150 x 150 x 750 mm unreinforced foamed concrete beams to flexural test and 150 x 300 mm cylinder specimens were subjected to splitting test. At the designed density of 1600 kg/m3, the modulus of rupture and splitting tensile strength were 2.53 and 1.63 MPa respectively with ratio of 0.64.
This study will focus on the chloride penetration to the concrete in various type of the strength and days of the concrete. This study is examined the effect of chloride to the concrete strength and durability of concrete on various type of concrete mixture proportion. Different type of concrete proportions mixture will give the dissimilar result of the experiment.
An example of one of the most common world applications where composites play a big role is bridges. A good number of bridges are held my concrete columns. The composites to fulfill this type of application are being alternated to help increase its ductility. The number of plate boding to involve thin composite laminates helps strengthen the concrete and many of the steel members for bridges. A bridge that was one of the first opened to car activity with the usage of composites was in Kansa City in 1996. This bridge was composited by honeycomb cells which were structural sandwiched. This allowed composites to be used among other bridges across the nation [2].
Sustainable concrete materials and sustainable steel reinforcement have been introduced to civil engineers to get closer to the sustainable development. Sustainable buildings constructed with use of these materials have shown an increased service life and the final cost has been reduced due to them.