Materials and Structures

, Volume 37, Issue 9, pp 585–590 | Cite as

A compact analytical material model for unconfined concrete under uni-axial compression

  • P. Kumar
Scientific Report

Abstract

The majority of the published material models for unconfined concrete under uni-axial compression consist of two branches. The recent trend is to introduce empirical modification factors in the existing material models to improve agreement between experimental and analytical results, particularly for High Strength Concrete. This paper presents a compact analytical material model in which the available conditions uniquely determine all the model parameters. It consists of a single branch and the need for empirical factors is eliminated. An application of this material model to published experimental data on normal and lightweight concretes over a wide strength range demonstrates its versatility. The agreement between experimental and analytical results is as good as that which may be provided by any other existing model. The rationality and elimination of empiricism are additional gains.

Keywords

Stress Strain Curve Peak Point High Strength Concrete Lightweight Concrete Initial Tangent Modulus 

List of symbols

Alphabets: A, B, C, D

Model parameters

E

Modulus

e

Error

f

Stress

k

Empirical modification factor

N

Number of data points

n

Model parameter

m

Derived quantity

U

Derived quantity

X

Dimensionless strain

Y

Dimensionless stress

Subscrips: g

General point

O

At origin

P

At peak point

Greek letter: ε

Strain

Résumé

La majorité de modèles de matériaux publiés pour du béton non confiné sous compression uni-axiale sont constitués de deux parties. Une tendance récente est d'introduire des facteurs de modification empiriques dans les modèles de matériaux existants afin d'améliorer la concordance entre les résultats expérimentaux et analytiques, en particulier pour le béton à hautes performances. Cette étude présente un modèle de matériau compact et analytique dans lequel les conditions disponibles déterminent d'une manière unique tous les paramètres du modèle. Il est constitué d'une seule partie et les facteurs empiriques ne sont plus nécessaires. Une application de ce modèle de matériau à des données expérimentales publiées sur des bétons ordinaires et légers pour une large gamme de résistances démontre sa souplesse. La concordance entre les résultats expérimentaux et analytiques est aussi bonne que celle que peut fournir un autre modèle existant. La rationalité et l'élimination de l'empirisme sont des avantages additionnels.

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References

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Copyright information

© RILEM 2004

Authors and Affiliations

  • P. Kumar
    • 1
  1. 1.Structural Engineering DivisonCentral Building Research InstituteRoorkeeINDIA

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