Factors affecting modulus of elasticity of concrete pdf

University of canterbury, christchurch, new zealand. International codes propose a wide variety of formulae which establish a relationship between modulus of elasticity and compressive strength. Results of experiments on the influence on shear strength of the size of the compression zone of the beam and of hooks on plain and deformed bars are presented. In recent years building specifications have even required a specific elastic modulus of concrete to be met, mostly to. Cement content mix must be designed to ensure cohesion and prevent segregation and bleeding. Elasticity modulus of concrete with recycled aggregate.

Modulus of elasticity of lightweight concrete containing. Physically it indicates a materials resistance to being deformed when a. The elastisitymodulus or emodulus is a property of a material like concrete or steel whichs tells how much tension is needed to make it a little bit longer or shorter when you pull at 2 ends of a steal beam itll be a bit longer then when you press it together. Therefore, the manufacture should choose the material in such a way that it should regain its elastic property even when it is subjected to large number of cycles of stress. This suggests the need to include the type of admixtures as another factor affecting modulus of elasticity. Mar 04, 2016 compressive strength of concrete is the most important properties of concrete the characteristic strength that is concrete grade is measured by 28day cylindercube strength. Aci committee 469, standard test method for static modulus of elasticity and poissons ratio of concrete in compression, american concrete institute, farmington hills, mich, usa, 2014. The elastic modulus was found to be the best indicator for identifying the progression of asr in concrete. Factors affecting the modulus of elasticity of concrete. The modulus of elasticity is a property of concrete, which is known for its high variability of. Many factors have been shown to influence the flexural tensile strength of concrete, particularly the level of stress, size, age and confinement to concrete flexure member, etc.

Most of these codes are valid up to 50 mpa, the usual limit for normal concretes. Most design specifications, such as the american association of state highways and transportation officials aashto bridge specifications, contain a constant value for the moe based on the unit weight of concrete and the concrete. It is defined as ratio of normal stress to longitudinal strain within the limit of proportionality. Test result of the elastic modulus is usually available for major structures but it is very rare that at least a shortterm creep test is carried. Effect of a time dependent concrete modulus of elasticity. Modulus of elasticity results of dynamic e tests are given in table 4, for water cured prisms, with 10% sf. The relationship between modulus of elasticity, e, and the product of compressive strength to the power and unit weight to the sec. Factors governing the strength and elastic properties of a. Shrinkage deformation affects durability, serviceability, longterm reliability, and structural integrity of concrete.

Jan 22, 2017 elastic modulus is a fundamental parameter in designing concrete structures. The strength of concrete is dependent on the relative proportion and modulus of elasticity of the aggregate. Parameters affecting the modulus of elasticity of concretes the elastic properties of concretes largely depend on the properties of their components. Modulus of elasticity also known as elastic modulus, the coefficient of elasticity of a material is a number which is defined by the ratio of the applied stress to the corresponding strain within the elastic limit.

The objectives of this study are to investigate the relationship between static and dynamic elastic moduli determined using shearwave velocity measurements and to demonstrate the practical potential of the shearwave velocity method for in situ dynamic modulus evaluation. Estimation of the static modulus of elasticity of concrete using the impulse excitation technique itc07 atcp br 1 1. Pauw, static modulus of elasticity of concrete as affected by density, aci journal proceedings, vol. Any concrete pavement, built of any thickness, will. The strength of concrete is basically referred to compressive strength and it depends upon three factors. Modulus of elasticity of concrete the modulus of elasticity of concrete e c adopted in modified form by the aci code is given by with normalweight, normaldensity concrete these two relations can be simplified to where e c modulus of elasticity of concrete, lbin 2 mpa. Development of the elastic modulus of concrete under different. The experimental evaluation of the modulus of elasticity of conventional concretes and with the re. The modulus of elasticity of concrete is a function of the modulus of elasticity of the aggregates and the cement matrix and their relative proportions. Experimental determination of factors affecting the static. Modulus of elasticity dynamic modulus of elasticity poissons ratio creep of concrete factors influencing creep relation between creep and time effects of creep shrinkage types of shrinkage.

Factors affecting modulus of elasticity as explained earlier, one of the important factors affecting the modulus of elasticity of concrete is the strength of concrete. There are a few normalised methods of assessing the elastic properties of. The modulus of elasticity young s modulus e is a material property, that describes its stiffness and is therefore one of the most important properties of solid materials. Elasticity modulus, shrinkage, and creep of highstrength. Youngs modulus does depend on orientation of a single crystal material. A study of factors affecting the flexural tensile strength. Some factors in the shear strength of reinforced concrete. Modulus of elasticity of concrete is a key factor for.

Structural concrete aci31899 and commentary aci 318r99. Resilient modulus is an important property for asphalt concrete design and for. Mar 09, 2017 modulus of elasticity of concrete as per is 456. Properties of hardened concrete strength, sjrinkage. Water tightness impermeability rate of strength gain of concrete. The primary objective of this study is to investigate the effect of cylinder size 100 by 200 mm and 150 by 300 mm on empirical equations that relate static and dynamic elastic moduli of concrete and static elastic modulus and compressive strength of concrete. Moreover, because of the stressstrain characteristics of concrete, it is probable that the modulus of elasticity of concrete, regardless of how it is determined, is a function of the stress intensity.

Factors affecting durability of concrete durability of concrete depends upon the following factors. Modulus of elasticity of concrete determination and. An evaluation of factors affecting the tensile properties of. Pdf key factors affecting the compressive strength of. Procedure overview the determination of the modulus of elasticity for cylindrical concrete samples such as molded cylinders and drilled cores is outlined in this procedure. Factors affecting price elasticity of demand economics. When a load is applied to concrete, it experiences an instantaneous elastic strain which develops into creep strain if the load is sustained. The ts500 equation eqn 21 generally overestimates the modulus of elasticity of low strength concrete ispir et al. The technical and scientific knowledge of the physical and mechanical behavior of concrete with recycled aggregates is not well established, and this is a knowledge gap, especially considering the use in structural elements. Binding forces, and thus the modulus of elasticity, are typically higher for high melting point materials. Loading conditions and moisture content of specimens. Estimation of the static modulus of elasticity of concrete using the impulse excitation technique itc07 atcp.

This can be represented in many ways such as the relationship between ratio of mix or watercement ratio. Strength, modulus of elasticity, creep and shrinkage of concrete. What are the factors affecting young modulus of elasticity. Sep 16, 20 civildigital powerpoint presentations building technology what are properties of hardened concretegoverning factors properties of hardened concrete properties of hardened concrete are explained on the basis of its strength and performance under various types of force actions and conditions. A general equation is derived which expresses the modulus of elasticity of concrete or mortar in terms of an empirical constant the elastic moduli of the cement matrix and aggregate constituents, and the mix proportions. Youngs modulus of concrete depends on many other factors such as moisture, the. A practical equation for elastic modulus of concrete. Pdf modulus of elasticity of low strength concrete. Factors affecting the modulus of elasticity of concrete may 23, 2018 by kathir leave a comment since concrete is a multiphase solid, no direct relationship can exist between its density and modulus as in singlephase solids such as metals. Elasticity theory of concrete and prediction of static emodulus for. In the theory of reinforced concrete, it is assumed that concrete is elastic, isotropic. Air travel and train travel are weak substitutes for intercontinental flights but closer substitutes for journeys of around 200400km e. Some factors affecting the dynamic modulus of elasticity. Modulus of elasticity of concrete increases approximately with the square root of the strength.

To determine the modulus of elasticity of concrete precisely is very important for structures that require strict control of the deformability. Kennedy, discusses factors important in determining the tensile strength of asphalttreated materials and reports findings of an evaluation of eight of these factors. The thesis aims to describe and evaluate the important factors that affect the final value of concrete modulus of elasticity, especially those that can be influenced during construction. The main factors which may affect the values determination of modulus of. The modulus of elasticity youngs modulus e is a material property, that describes its stiffness and is therefore one of the most important properties of solid materials. High strength concrete is characterized by a dense interfacial transition zone itz and behaves differently from low strength concrete. Pdf this contribution aims to highlight, from an experimental point of view, the key factors affecting the compressive strength of foamed concrete. The concrete technology notes pdf ct notes pdf book starts with the topics covering portland cement, mineral and chemical admixtures, classification of aggregate, factors affecting workability, water cement ratio, compression tests, factors. Physically it indicates a materials resistance to being deformed when a stress is applied to it. Experimental determination of factors affecting the static modulus of elasticity of concrete using nondestructive testing methods. This stronger delivered concrete as well the concrete age may give reason for that the modulus of elasticity used in design gives the correct structural deformations. Another aim is to find ways to determine the static modulus of elasticity of concrete by nondestructive means primarily ultrasonic pulse method, resonance method and use of electronic rebound hammers, thus to determine the possibility of creating calibration curve for ndt determination of the modulus of elasticity. Chapter 1 properties of reinforced concrete strength of. Estimation of the static modulus of elasticity of concrete.

Factors affecting elasticity in engineering physics tech. The type of aggregate and the size of the aggregate particles can also influence the tensile strength. Factors affecting deflections of rcc beams and slabs. Here you can download the free lecture notes of concrete technology pdf notes ct pdf notes with multiple file links to download. Some factors affecting the dynamic modulus of elasticity of. While there are many factors for high seismic vulnerability of existing buildings, poor quality of concrete is a major and widespread problem for.

Modulus of elasticity of concrete can be defined as the slope of the line drawn from stress of zero to a compressive stress of 0. Standard cylinder 150x300 mm or 150x100 cube with aggregate size of which is not exceeding 25mm is used to determine the strength. Several of the numerical approximations presented for the stressstrain diagram can take some of these effects into consideration. Factors affecting workability of concrete civil engineering. How to fit a concrete cylinder with compressometerextensometer for elasticity modulus test duration.

Factors affecting youngs modulus the modulus is closely related to the binding energies of the atoms. It is found that bodies lose their elastic limit, due to elastic fatigue. A parametric study was conducted to explore the effect of the interfacial transition zone itz or interphase on the overall elastic modulus of the cntreinforced cement. Properties of hardened concrete strength, sjrinkage, creep. Modulus of elasticity of concrete civil engineering.

Concrete is a composite consisting of matrix and aggregates. Previous research on geopolymer material the term geopolymer describing a family of mineral binders those have a polymeric siliconoxygenaluminum framework structure. Creep does not necessarily cause concrete to fail or break apart. The results show that the curing method strongly affects not only the development, but. The modulus of elasticity of high performance concrete. Effect of stress on the dynamic modulus of concrete. Concrete technology 11 factors affecting the selection of repair materials 11 factors affecting the selection of repair materials there are a number of factors such as strength, durability, thermal coefficient of thermal expansion, permeability, low dry shrinkage, chemical and electrical properties, curing, and cost that must be considered to select the most appropriate. It might vary along the member length and is likely to reach average in its influence on deflection. The number of close substitutes the more close substitutes there are in the market, the more elastic is demand because consumers find it easy to switch.

More over, the modulus of elasticity in design is based on concrete 28 day strength, but the concrete, when becomes older, increases its strength and also modulus. The modulus of elasticity of concrete is relatively constant at low stress levels but starts decreasing at higher stress levels as matrix cracking develops. The ratio between static and dynamic modulus of elasticity in normal and high strength concrete abstract there is a simple linear relationship between the static and dynamic elastic module, this lead to hope that using dynamic elastic modulus may remove the problems in measuring the static elastic modulus of concrete. Pdf influence of coarse aggregate on concretes elasticity modulus. Concrete technology notes pdf ct notes pdf eduhub sw. Motivation and goal the modulus of elasticity is a fundamental property for concrete and it has become increasingly common for designers to specify a minimum value to be met. 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. For a more realistic interstory ratio prediction, the modulus of. Effect of cylinder size on the modulus of elasticity and. Pdf evaluation of elastic modulus reduction due to asr. Conversely, the evolution of compressive strength was. The influence of concrete composition on youngs modulus core.

Relationship between compressive strength and modulus of. Modulus of elasticity iof concrete affected by elastic moduli. Concrete modulus of rupture is more changeable than compressive strength. Modulus of rupture modulus of elasticity modulus of subgrade reaction 198693 rigid pavement design equation. Evaluating the dynamic elastic modulus of concrete using. If cement is reduced, then at fixed wc ratio the workability will be reduced leading to inadequate compaction. Higher strengths give higher value of modulus of elasticity. The concrete members, in general, are of large continuous size and have at least minimum reinforcement introducing a confining effect to the concrete. Modulus of elasticity of concrete concrete technology. Since concrete is a composite material, consisting of cement paste and aggregate, its modulus of elasticity depends on the moduli of elasticity and the volume fractions of cement paste and aggregate. Laboratory tests showed the equation to produce good results over a wide range of variables. Factors in the choice of mix proportions bis and aci methods of mix design. Creep is factored in when concrete structures are designed.

It is one of the most important factors which affect the modulus of elasticity. Procedure for measuring the modulus of elasticity of concrete cores and cylinders rev. Stress, strain and youngs modulus calculator epsilon. The concrete technology notes pdf ct notes pdf book starts with the topics covering portland cement, mineral and chemical admixtures, classification of aggregate, factors affecting workability, water cement ratio, compression tests, factors in the choice of mix.

The different types of shear failure of reinforced concrete rectangular and tbeams are described in order to show that the shear strength depends on factors additional to those recognized by the design formulae. The mechanism of geopolymerisation may consist of dissolution, transportation or orientation, and. Aci 31808, normal weight concrete the modulus of elasticity of concrete is, ec 4700 vfc mpa and. For isotropic materials, the presence of fractures affects the young and the shear modulus perpendicular to the planes of the cracks, which decrease youngs modulus faster than the shear modulus as the fracture density increases, indicating that the presence of cracks makes bodies brittler. Concrete compressive strength could be higher as much as 15% than specified and increase modulus of elasticity by 7%. What are properties of hardened concretegoverning factors. As a consequence, such models can only be used to evaluate the effects produced by the concrete components on the modulus of elasticity. Chapter 15 modulus of elasticity page 85 tab36 value of modulus of elasticity for some materials material modulus of elasticity gpa aluminium and its alloys 65 73 ceramics 8 12 concrete 15 40 copper 125 diamond lightweight concrete 0,8 2 low alloy steels 200 210 polystyrene 3,2 3,5 silica glass 60 90. Home tools stress, strain and youngs modulus calculator calculators for stress, strain and youngs modulus modulus of elasticity, elastic modulus stress, strain and youngs modulus are all factors linked to the performance of a material in a particular setting. The effect of interfacial transition zone properties on. Factors affecting the tensile properties of concrete. Modulus of elasticity of concrete ec is defined as the ratio of the applied stress to the corresponding strain.