This document discusses early-age cracking in concrete, which can occur within the first 60 days after placement. It focuses on the types, causes, and factors influencing early cracks. Early cracks can affect structure appearance and raise safety concerns. Long-term maintenance issues may also result if cracks are not addressed. The document then provides methods to minimize early cracking, such as limiting temperature differences, using shrinkage-reducing admixtures, and selecting appropriate mix designs and construction sequences. It proposes studying early-age stresses and strains, mix parameters, and environmental conditions to reduce cracking.

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2.  Early cracks are defined as cracks that generally develop within the
first seven days after the placement of concrete; however, 60 days
can be considered the maximum limit for early cracking,
accounting for the initiation of cracks at the bottom of the concrete
slab that may take more than one week to be visible
 The early characteristics of concrete have been a point of research
interest for a long time, and researchers have focused on studying
different aspects of the early-age characteristics
 This provides a unique perspective on early concrete by focusing
on the types of early crack, the causes of early cracking, the factors
influencing the initiation and growth of early cracks, the
consequences of early cracking, and measures for early cracking.
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3.  These cracks affect the appearance of structures.
 Early age cracks raise public concern and attention regarding
safety issues.
 Early-age cracking, if left unchecked, may lead to long-term
maintenance issues.
 The function of some concrete structures may be affected
over time, especially in structures like water reservoirs and
roofs, due to early-age cracking.
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1. The early-age cracking in concrete can be minimized by limiting
temperature differences in concrete.
2. It can be reduced by using shrinkage reducing admixtures.
3. Appropriate selection of the constituent materials for concrete, the
correct mix design of concrete, proper planning of concrete casting and
construction sequence and the cooling of concrete before or after placing
are some of the measures to minimize the risk of the early-age cracking
in concrete structures
Solutions:-

11.  To study different types of temperature and thermal stresses
and strain which develop early cracks in concrete specimen.
 To study mix proportion , material and mix parameters to
minimize the early cracks in concrete.
 To suggest the environmental condition that helps in reducing
early age cracks.
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12.  Determine whether the cracks are isolated or widespread.
 Apply an iteration process to identify one or more major causes
and verify the major causes one by one with field observations.
 Collect samples by conducting laboratory testing.
 Employ one or more nondestructive on-site assessment.
 Develop a database to record, analyze, and examine the formation
and causes of early-age cracks in concrete.
 Smear dry cement powder on the concrete surface in the presence
of bleed water to reduce the probability of the formation of early-
age cracks in newly placed concrete elements.
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13. 1. ACPA. Concrete Crack and Partial-Depth Spall Repair Manual
for Airfields; American Concrete Pavement Association:
Rosemont, IL, USA, 2003.
2. Bentz, D.P. A Review of Early-Age Properties of Cement-
Based Materials. Cem. Concr.
3. Stark, J. Recent Advances in the Field of Cement Hydration
and Microstructure Analysis. Cem. Concr. Res.
4. Kim, J.H.; Ferron, R.P.; Shah, S.P. Fresh Concrete and Its
Significance for Sustainability. J. Sustain. Cem.-BasedMater.
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