Introduction to concrete concretess versatility, durability, sustainability, and economy have made it the worldss most widely used construction material. An outgrowth of the development of nuclear energy, high density concrete is gaining wide spread use as a shielding material to provide protection against radiation hazards. High density concrete, high strength concrete and high. Figure 1 shows the polyethylene fiber used in this research and tables 1,2,3 and 4 shows the properties of the material. Material property characterization of ultra high performance concrete publication no. It is a type of high performance concrete generally with a specified compressive strength of 6,000 psi 40 mpa or greater. High density concrete high density concrete is a concrete having a density in the range of 6000 to 6400 kgcu. High modulus of elasticity, low thermal expansion, and low elastic and creep deformation are the ideal properties for both high density and normal concrete. High performance means that the concrete has one or more of the following properties.
The properties of high density concrete made with sheared mild steel bars as coarse aggregate and sand as fine aggregate are studied through experimental investigations. Except in the nuclear industry, high density radiation shielding concrete used by offshore oil industry as a layer to cover pipelines under the sea and usually magnetite concrete is applied as shown in figure4 and figure5. Concrete basicsaddresses the needs of unskilled and semiskilled persons. Pdf mechanical properties of highdensity polyethylene. Lightweight concrete can weigh as little as 95 lbscu ft. Founded in 1904 and headquartered in farmington hills, michigan, usa, the american concrete institute is a leading authority and resource worldwide for the development, dissemination, and adoption of its consensusbased standards, technical resources, educational programs, and proven expertise for individuals and organizations involved in concrete design. The strength of this concrete measured on standard cylinders has been found 42 mpa at 28 days for a watercement ratio 0. The dry density of foamed concrete may vary from 300 to 1600 kgm3.
Use of wellgraded aggregate of the largest possible maximum size. Other applications of high density radiation shielding concrete. The term concrete refers to a mixture of aggregates, usually sand. Highdensity concretes range from 190 to 260 lbscu ft. Because of the deep water, 345m 1 ft, above the heidron oil fields, a decision was made to construct the first floating platform with high strength low density concrete hssdc. High density concretes for radiation shielding concrete.
This is an effective and easy way to deduce dead load of the structure. The density of light weight concrete is about 1900 kgm 3 and that of normal concrete about 2400 kgm 3. Experimental study on foam concrete 147 the objective of this study is to. Concrete which is subjected to longduration forces is prone to creep. With a fixed amount of cement in a unit volume of concrete, the strongest and most impermeable concrete is one that has the greatest density, i. Cip 33 high strength concrete what is high strength concrete it is a type of high performance concrete generally with a specified compressive strength of 8,000 psi 55 mpa or greater. Durability properties of high performance foamed concrete. For a given unit configuration, the fire resistance of a concrete masonry wall increases as the concrete density decreases. Highperformance concrete is often nomically made while used in bridges left and tall buildings right. This video animation, animated video explains the concept of high density concrete.
The unit geometry affects the effective or equivalent unit thickness. Uniform consolidation is key to achieving uniform and optimum density. The concrete mixtures incorporate either basalt or crushed limestone, aggregate sizes of 12 mm h in. High density concrete is used in nuclear power plants npp for primary and secondary containments structures. To provide detailed properties of the concrete, this study also discusses two heavy concrete types s50 and s100 from scientific publication designing of high density concrete by using steel. Workability in concrete defines its capacity to be placed, consolidated, and finished without harmful segregation or bleeding.
Design and development of high strength heavyweight. The factors that contribute to high density for all types of concrete are. Its primary use is in radiation shielding, either in nuclear power plants or in radiation therapy. In contrast with conventional concrete weighing around 150 pounds per cubic foot, high density concretes normally weigh from 200 to 250 pounds per cubic foot. High density concrete the heavyweight of all concretes. Concrete basicsaims to provide a clear, concise explanation of all aspects of making quality concrete. Bickley and fung 2001 demonstrated that 40 mpa 6,000 psi high performance concrete for bridges could be ecofig. Cip 36 structural lightweight concrete what is structural lightweight concrete structural lightweight concrete has an equilibrium density ranging from 90 to 120 lbft3 31440 to 1840 kgm compared to normalweight concrete with a density in the range of 140 to 150 lbft 3 2240 to 2400 kgm. The excellent particle characteristics of ferroshield ferrodense enable the easy production of high quality, high strength concrete with a density of up to 240 lbs. Properties of concrete concrete is an artificial conglomerate stone made essentially of portland cement, water, and aggregates.
Results of the characteristics of different grades of concrete using mix design method are discussed in terms of density, compressive strength, flexural strength and workability. Properties of different grades of concrete using mix. Concrete must has to ensure satisfactory compressive strength and durability. Properties of highdensity concrete astm international. The main activities for controlling quality on site are placing, compaction, curing and surface finishing. Concrete, normalweight concrete having a density of 140 to 155 lbft. A hollow unit is that unit which has core void area greater than 25% of the gross area. Despite the common usage of concrete, few people are aware of the considerations involved in designing strong, durable, high quality concrete. Mechanical properties of high strength concrete hsc can be divided in two groups as shortterm mechanical properties and longterm mechanical properties. The paste is composed of cement, water, and entrained air and ordinarily constitutes 20 to 40 percent of the total volume. Test results indicate that high density concrete with densities ranging from 3400 5600 kgcu m and compressive strengths varying from 200. This permits volumetric changes to ta ke place more uniformly throughout the concrete. The chances of bleeding in foamed concrete are reduced due to high air content.
Introduction high density or heavyweight concrete is concrete with a density greater 3than 2600kgm. Concrete, sand lightweightconcrete with coarse lightweight aggregate and normalweight fine aggregate. High density concrete can be used for structural andor specialised construction purposes. High density concrete is a concrete having a density in the range of 6000 to 6400 kgcu. Highdensity concrete article about highdensity concrete. High density concrete high densityheavyweight density should be more than 2600 kgm3 dens crete offers more strength can be used everywhere, in all construction practices resistant to extreme weather. It was named portland cement because it looked like the. The density of concrete varies, but is around 2,400 kilograms per cubic metre 150 lbcu ft. The concrete mix design cmd for qcqa superstructure concrete must produce a workable concrete mixture having properties that will not exceed the maximum andor minimum values defined in the special provision. View high density concrete research papers on academia. As the name suggests, the density of this concrete varies from 3360 kgm 3 to 3840 kgm 3, whereas the density of normal concrete is of the order of 2400 kgm 3.
High density concrete using fly ash, micro silica and. Properties of concrete every civil engineer must know. Determine the influence of the density and compressive strength of foamed concrete with and without sand. The number and size of the pores in a sample of given density is a function of the particles and their size distribution and determines the rate of air flow through the sample. The high strength concrete has a lower value of permeability compared to normal strength concrete. Introduction and overview concrete is the most widely used building material in the world. In buildings, concrete is used for footings, foundations, columns, beams, girders, wall slabs, and roof unitsin short, all important building elements. High density concrete is mainly used for the purpose of radiation shielding, for counterweights and other uses where high density is required. Bickley and fung 2001 demonstrated that 40 mpa 6,000 psi highperformance concrete for bridges could be ecofig. In hd concrete, vibrators have a smaller effective area, or radius of action.
High density radiation shielding concrete applications in. The effects of aggregate type, size, and content on the behavior of normal and highstrength concrete, and the relationships between compressive strength, flexural strength, and fracture energy are discussed. The main use of hdc is in the nuclear industry as radiation shielding. Mechanical properties of highstrength concrete manish kumar. Properties of concrete while cement in one form or another has been around for centuries, the type we use was invented in 1824 in britain. Over 35% less effective in preventing radiation streaming. Color pigments in powder or liquid form may be added to the concrete mix to produce colored concrete. Hemp concrete is highly porous, with open and interconnected porosity.
Pdf relation between density and compressive strength of. A discussion on shortterm mechanical properties of concrete which includes, compressive strength, stressstrain behavior. Introduction to concrete portland cement association. Following properties of high density concrete have been observed. The use of high performance fc with improved durability increases exploitation time and duration of. The study provides a comparison of the above mentioned uhpfrc properties with high performance concrete, fiber reinforced concrete and conventional structural concrete. Heavyweight concrete is made and transported much like traditional ready mix concrete, but due to its high density and weight properties, it is usually transported in smaller amounts. The density of the sdc combined with the extremely high concentration of reinforcement was 2,240 kgm3 140 lbft3. Concrete has a great variety of applications because it not only meets structural demands but also lends itself readily to architectural treatment. Composition of concrete mixtures used in cylinders tested. Fhwahrt06103 august 2006 research, development, and technology turnerfairbank highway research center 6300 georgetown pike mclean, va 221012296.
The relatively high cost of steel mandates its sparing use. Ouda housing and building national research center hbrc, dokki, giza, egypt ahmed. Oct 31, 2010 concrete of over 300 pounds per cubic foot has been used for radiation shielding in volumelimited applications particle accelerators for medical treatment located inside existing structures. Using heavy aggregates in a mix can create a high density concrete suitable for use in medical and nuclear applications such as radiation shielding. Commercially used aerated silicate low density concrete has the least durability 10 cycles, but fc produced in turbulence mixer has frost resistance 100 cycles, which is comparable with normal concrete. High performance concrete is a term used to describe concrete with special properties not attributed to normal concrete. Concrete has become a universal building material which is extensively used in civil engineering construction. Site experience indicates that more compaction is normally needed for high strength concrete with high. The neutron shielding properties of a new high density concrete commercially available under the name hormirad, developed in spain by the company ctrad have been characterized both experimentally and by monte carlo calculations. Radiation shielding with high density concrete lkab. High density concrete can only be manufactured by using various high density natural or manmade aggregates.
These are usually used with white portland cement to attain their full coloring potential. The strength of concrete is the next important pr operty to consider. Ultimately, there are several construction solutions for using the high density aggregate magnadense to build a radiationprotected room or bunker to provide the right degree of defence standard heavy concrete walls. Reduces the effectiveness of a 6 block thickness to the same as a 4 block. This is because the high strength concrete is designed with lower water cement ratio. The grout used in high density pre placed aggregate concrete should be somewhat richer than that used in normal density pre placed concrete. Influence on properties of concrete pozzolanic reaction in the contact zone 6. Properties of highdensity concrete made with iron aggregate. The high density concrete has a better shielding property, so that it can. What is the highest density concrete ever used commercially. Some of the natural minerals used as aggregates in high density concrete are hematite, magnetite, limonite, barite and some of the artificial aggregates including materials like steel punchings and iron shot. Some of the natural minerals used as aggregates in high density concrete are hematite, magnetite, limonite, barite and some of the artificial aggregates include materials like steel punchings and iron shot. Today compressive strengths exceeding 20,000 psi 140 mpa have been used in castinplace buildings.
Development of highperformance heavy density concrete using. This research aims to improve the mechanical properties of concrete by. High density concrete blocks learn more about high density concrete blocks 2 approx. Development of high performance heavy density concrete using different aggregates for gamma ray shielding ahmed s.
Nov 26, 20 high density concrete, high strength concrete and high performance concrete. The mechanical properties of concrete are highly influenced by its density. Abstract heavyweight concrete is used in many applications such as bascule and lift bridges, radiation shielding structures in nuclear. The aggregates and other components are based upon the exact application of the high density concrete. Chapter 1 components of concrete concrete is made up of two components, aggregates and paste. Safety features in the building include the high density concrete core, which surrounds wide staircases of poured concrete, according to frank hussy of tishman construction, who is supervising the construction site. Hemp concrete is environmentally friendly as it is made of a renewable raw material hemp and as it allows carbon sequestration boutin and al.
Zhenhai guo, in principles of reinforced concrete, 2014. Development of high performance heavy density concrete using. Pdf designing of high density concrete by using steel. Introduction these are the concrete blocks either hollow or solid. The high strength concrete has a permeability coefficient that ranges from 1 x 10 11 to 1 x 10 cmsec. Highdensity concrete is used extensively in nuclear power plants for radiation shielding against biological hazards. High density concrete is used extensively in nuclear power plants for radiation shielding against biological hazards. Concrete is a composite material obtained by mixing cement, sand, aggregates, and water in suitable proportions. The compressive strength of foam concrete determined at 28 days, ranges from 0. High performance concrete is often nomically made while used in bridges left and tall buildings right. The properties of high density plastics fibers shown in table 3, this fibers used as percentages of volume of concrete with ratios of 0%,0. High density aggregates like barites, hematite, ironshots, goethite, etc are used to produce high density concrete the major performance requirement of this kind of concrete is durability that it should withstand adverse environments. Custom radiation protection, shielding and storage high.
In applications of concrete for shielding against hazardous radiation or for being used as counterweight, as well as in various other applications that involve the use of heavyweight concrete, the most significant method of mix design involves the use of heavyweight aggregates. All concrete structures will crack to some extent, due to shrinkage and tension. Concrete has a very low coefficient of thermal expansion, and as it matures concrete shrinks. Pdf neutron shielding properties of a new highdensity. Calculations are made and the fineness is expressed in terms of cm2g or m2kg. When using only magnadense as a high density aggregate, concrete with densities up to 4.
About four tons of concrete are produced per person per year worldwide and about 1. Properties of ferromin custom made high density aggregates. Density and specific gravity density is the weight per unit of volume of a substance. Foam concrete materials, properties, advantages and. Bulk density determination bulk density of the specimen could be determined by three methods from dimensions. Cip 33 high strength concrete what is high strength concrete. High density concrete is also known as heavy weight concrete. It is a type of high performance concrete generally with a specified compressive strength of 6,000 psi 40 mpa or. Specific gravity is the ratio of the density of the substance to the density of water. Mixing magnadense into concrete with other aggregates allows you to produce even heavyweight concrete with densities up to 5. The effects of aggregate type, size, and content on the behavior of normal and high strength concrete, and the relationships between compressive strength, flexural strength, and fracture energy are discussed.
296 1167 522 592 136 892 1274 1219 828 1105 1422 1080 944 350 1067 1166 1281 919 448 1078 119 55 964 746 787 439 538 1002 1478 1152 1076 833 543 1451 281 789 403 1390 1252