Page 1 of 7

European Journal of Business &

Social Sciences

Available at https://ejbss.org/

ISSN: 2235-767X

Volume 07 Issue 05

May 2019

Available online: https://ejbss.org/ P a g e | 1601

Mechanical Behaviour of Super Absorbent Polymer Concrete

MAHESWARI. S

DEPARTMENT OF CIVIL ENGINEERING

PRIST UNIVERSITY, THANJAVUR - 613 403

ABSTRACT

Internal curing refers to the process by which the hydration of cement occurs because of

the availability of additional internal water that is not part of the mixing Water. Excessive

evaporation of water (internal or external) from fresh concrete should be avoided; otherwise, the

degree of cement hydration would get lowered and thereby concrete may develop unsatisfactory

properties. Curing operations should ensure that adequate amount of water is available for

cement hydration to occur. This paper discusses different aspects of achieving optimum cure of

concrete without the need for applying external curing methods. Self-Curing of concrete (SCC)

can be done by adding admixtures while mixing the concrete in two ways. The admixtures may

be added in the form of powder or liquid. This study reports experimental results of selected

performance features of SCC. In Self Curing of Concrete the admixture added is Hydropod.

Concrete mixtures are produced by the addition of Hydropod for the ratio of 0.1%, 0.2%, 0.3%,

0.4% and 0.5% to the weight of cement. The properties like workability, compressive strength

and split tensile strength of Self Curing of Concrete are investigated in this present study.

1. INTRODUCTION

The ACI-308 Code states that “internal curing refers to the process by which the hydration of

cement occurs because of the availability of additional internal water that is not part of the

mixing Water.” Conventionally, curing concrete means creating conditions such that water is not

lost from the surface i.e., curing is taken to happen ‘from the outside to inside’. In contrast,

‘internal curing’ is allowing for curing ‘from the inside to outside’ through the internal reservoirs

(in the form of saturated lightweight fine aggregates, superabsorbent polymers, or saturated

wood fibers) Created. ‘Internal curing’ is often also referred as ‘Self–curing.’

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European Journal of Business &

Social Sciences

Available at https://ejbss.org/

ISSN: 2235-767X

Volume 07 Issue 05

May 2019

Available online: https://ejbss.org/ P a g e | 1602

When the mineral admixtures react completely in a blended cement system, their demand for

curing water (external or internal) can be much greater than that in a conventional ordinary

Portland cement concrete. When this water is not readily available, due to depercolation of the

capillary porosity, for example, significant autogenous deformation and (early-age) cracking may

result.

Due to the chemical shrinkage occurring during cement hydration, empty pores are created

within the cement paste, leading to a reduction in its internal relative humidity and also to

shrinkage which may cause early-age cracking. This situation is intensified in HPC (compared to

conventional concrete) due to its generally higher cement content, reduced water/cement (w/ c)

ratio and the pozzolanic mineral admixtures (fly ash, silica fume). The empty pores created

during self-desiccation induce shrinkage stresses and also influence the kinetics of cement

hydration process, limiting the final degree of hydration. The strength achieved by IC could be

more than that possible under saturated curing conditions.

Often specially in HPC, it is not easily possible to provide curing water from the top surface at

the rate required to satisfy the ongoing chemical shrinkage, due to the extremely low

permeabilities often achieved.

MIX DESIGN

For making concrete, it is essential to select proper ingredients, evaluate their properties and

have the know-how of the interaction of different materials for optimum usage.

Cement 43 Grade ordinary Portland cement purchased locally was used for casting the

specimens.

Aggregate River sand and 20mm size coarse aggregate used for casting the specimens.

Water It is generally stated that the water fit for drinking is fit for making concrete. Potable

drinking water was used for both mixing and curing of concrete specimens.

Indian standard recommended mix design procedure was adopted for arriving mix proportions

for M25 and M35 grade concretes.

Page 3 of 7

European Journal of Business &

Social Sciences

Available at https://ejbss.org/

ISSN: 2235-767X

Volume 07 Issue 05

May 2019

Available online: https://ejbss.org/ P a g e | 1603

Factors to be considered for mix design

The grade designation giving the characteristic strength requirement of concrete.

The type of cement influences the rate of development of compressive strength of

concrete.

Maximum nominal size of aggregates to be used in concrete may be as large as possible

within the limits prescribed by IS 456:2000.

The cement content is to be limited from shrinkage, cracking and creep.

The workability of concrete for satisfactory placing and compaction is related to the size

and shape of section, quantity and spacing of reinforcement and technique used for

transportation, placing and compaction.

The Mix proportion is shows below

For M25 Grade concrete

Cement : Fine aggregate : Coarse Aggregate : W/c ratio

1 : 1.51 : 2.57 : 0.45

Experimental Details:

Ordinary Portland Cement (OPC) of 43 Grade conforming to Bureau of India Standard (BIS)

Specifications of IS: 8112 (1989) with specific gravity 3.05 was used in this study. The locally

available natural sand conforming to grading Zone II of IS: 383 (1970) was used in the

production of concrete. 20 mm maximum size natural coarse aggregate available from the local

quarries conforming to the grading requirements of IS: 383 (1970) was used. The super