Advantages Of Geopolymer Concrete

Concrete floor is one of the most durable materials in the world. It can be made with waste products which help to reduce the consumption of valuable materials. It also can be made from fly ash, slag cement, and silica fume, all waste byproducts from steel mills, power plants and other manufacturing facilities.

Aggregate is one of the basic constituents of concrete. Its quality is of considerable importance because about three-quarter of the volume of concrete is occupied by aggregates. One of the physical properties of aggregate that influence the property of concrete is the grading of aggregate. The grading of aggregate defines the proportions of particles of different size in the aggregate. The grading of fine (size < 5 mm) and coarse (size > 5 mm) aggregates are generally required to be within the limits specified in BS 882: 1992.

Concrete is a vital construction material having high compressive strength and comparatively low tensile strength. Based on fracture toughness values, steel is at least 100 times more resistant to crack growth than concrete. Concrete in service thus cracks easily, and this cracking creates easy access routes for deleterious agents resulting in early saturation, freeze-thaw damage, scaling, discoloration and steel corrosion.

Concrete is the second most utilized substance in the world after water and is the most widely used construction material with an annual global production of about 10 billion tonnes. It is preferred in most structures because of its unique properties such as durability and high compressive strength. It is however relatively weak in tension, its tensile strength being about 10-15 % of its compressive strength requiring that it be reinforced with materials such as steel rods, glass or plastic fibers in order to improve its ductility. It is also prone to slight shrinkage during the drying process and may lead to cracking especially in normal strength concretes. (R. I. Gilbert, 2001). As defined by the Portland Cement Association, the durability of concrete is its ability to counteract abrasion, weathering action and chemical attack, and still maintain its desired engineering properties. The proportioning and interactions between concrete ingredients, placement and curing practices as well as the service environment determine this ultimate durability and life. The ideal situation therefore in any construction project is to choose the correct concrete type which will be more durable based on the project requirements.

Concrete has no opinion about its shape; a gloppy material, it will take any shape give it, as long as it’s given time to cure. Traditionally, concrete is cast using rigid panels like plywood. Although reinforce concrete become the standard in the last decades, few of its potentialities have been fully exploited. “Apart from the unconquerable inertia of our minds, which do not seem to be able to adopt freely new ideas, the main cause of this delay is a trivial technicality: the need to prepare wooden forms” (Nervi, 1956, p. 95). Most industrial material are produced through single axis mills. This produced uniform surface. The obvious exceptions are cast materials such as concrete. But if concrete is cast into molds made of rigid, flat material produced by milling, the result will likely be flat and straight forms. Fabric formwork is a building technique that uses structural membranes as the main material for concrete molds. Unlike traditional formwork, fabric formwork is highly flexible and can deflect under the pressure of concrete. The results are variety of shapes that are not normally associated with concrete. As buildings become more complex, there is an increasing demand for molding creative and organic forms. Concrete, theoretically, is the perfect material to make a variety of shape. Fresh concrete can be shaped in different types of formwork. “The visual appearance and effect of fabric-formed concrete is strikingly different from that of conventional concrete

Concrete is a significant structural material used all around the world. Moreover, the complexity of structures and their magnitude have continued to increase, and this has resulted in a greater importance of their strength and distortion characteristics in more serious consequences of their behaviour. Engineers have been working on the development of innovative types of concrete. One of the most promising products is fiber-reinforced concrete (FRC). Fibers in concrete provide better-quality mechanical and physical properties of the material. For example, the obtained fiber-reinforced concrete has higher resistance to cracking. In this paper we will be discussing fiber reinforced concrete as an alternative to the conventional concrete.

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).

Lightweight concrete can also be classified according to the purpose of utilizing as: i) Structural lightweight concrete has cylinder compressive strength at 28 days equal or more than 17 MPa and the approximate density range is about 1400-1800 kg/m3. ii) Masonry concrete (structural / insulating lightweight concrete) has a compressive strength between 7-14 MPa and density range 500-800 kg/m3. iii) Insulating concrete has a compressive strength between 0.7-7 kg/m3 and density lower than 800 kg/m3. (Neville and Brooks, 2010; Slaby, Aziz and Hadeed, 2008)

Abstract— An experimental program was conducted to assess the influence of addition of steel fibers to Self Compacting Concrete (SCC). The objective was to assess and compare the various mechanical properties of self compacting concrete with and without steel fibers. Various percentage of steel fibers viz. 0%, 1%, 3%, 5% and 7% were added. The effect on the properties of the fresh concrete was studied by means of slump test, V-funnel test, L box test etc. The properties of hardened concrete were investigated by assessing the compressive strength and split tensile strength. Lastly the optimum dosage of steel fibers was suggested.

A preliminary investigation of strength and durability properties of a low-cost concrete-like system made of pH-adjusted fluorogypsum (FG), class C fly ash (FA), and type II Portland cement (PC). A series of compressive strength tests and volumetric expansion measurements were conducted on specimens after 28 days of curing. The experimental results were used to develop response surface models (RSMs). These RSMs can be used to predict accurately compressive strength and volumetric expansion as functions of the relative content, in dry weight, of different components. The RSMs

Successful design of underwater concrete mixtures must fulfill two basic requirements: adequate flowability to spread into the placing forms without consolidation, and viscosity in order to resist the washing out. In this paper an investigation was carried out to determine the effect of the dosage of antiwashout admixture (AWA), watercementitious materials ratio (w/cm),sand to total aggregate ratio(s/a), and the supplementary cementitious materials on the washout resistance, fresh properties and the relative compressive strength of self compacting underwater concrete (SCUWC). Therefore five groups were prepared for this study.First group studied the effect of the supplementary cementitious materials, second group dealt with the effect of the AWA ratios, third group is concerning with the effect of w/cm ratio, fourth group take into account the effect of s/a ratio and finally fifth group included the effect of cementitious materials. Test results indicate that the concentrations of

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.

Abstract: Natural Sand which is used as a construction material is becoming scarce now-a-days and state governments are imposing restriction on unlimited excavation of Natural sand from river beds. This has made prices of Natural sand reach its peaks. Now there is every need for a suitable replacing material for Natural sand. An attempt is made in this context to replace natural sand by Granite fines by adopting M20 Grade concrete with a mix design of 1: 1.73: 3.1 of cement: Natural sand& Granite Powder : Gravel at a proportions of 0, 10%, 20%, 30% and 40% with a water cement ratio of 0.5. Acid Durability test was conducted on concrete cube specimen after 28 days water curing and 62 days soaking in Hydro Chloric Acid. After completion of this procedure Concrete cubes are tested for Compressive strength is tested and compared with Compressive strength of cubes which are not soaked in HCL after 90 Days. Cost analysis is done to ensure usage of Granite fines as replacement of Natural Sand does not vary the cost of project significantly.

Cement production is the result of chemically combination of different materials. These materials include “calcium”, “silicon”, “aluminum”, “iron” and other materials such as clay and limestone. Moreover, the production process involves crushing and screening of certain amount of “calcium compounds”, “silica”, “alumina” and “iron oxide”. After this process the whole mixture is placed in “rotating cement kiln”. Different kind of materials are used in this regard. These include “limestone”, “sandstone”, “marl”, “shale”, “iron”, “clay”, and “fly ash”.

Abstract-Concrete is the most widely used construction material in civil engineering industry because of its high structural strength and stability. Cement and sand is a major constituent material of the concrete which produced by natural raw material like lime and silica and natural sand respectively. Once situation may occurs there will be no lime on earth production of cement also natural sand. This situation leads to think all people working in construction industry to do research work on cement replacing material and natural sand for use of it. The construction industry is constantly looking for supplementary cement and natural sand material with the objective of reducing the solid waste disposal problem. Ground granulated blast furnace slag (GGBS), quarry sand are the solid wastes generated by Industry. To overcome from this crisis, partial replacement of Cement with GGBS, natural sand with quarry sand (QS) can be an economic Alternative. The cubes are tested for compressive strengths. Ordinary Portland cement was partially replaced by GGBS of 0%, 30%, 40%,50% and natural