Combined effect of shrinkage reducing admixtures (SRA) and superabsorbent polymers (SAP) on the autogenous shrinkage, hydration and properties of cementitious materials

Superabsorbent polymers (SAPs) are promising admixtures to improve properties in cementitious materials. Not only useful to mitigate autogenous shrinkage and to increase the freeze-thaw resistance, SAP particles may enhance self-sealing and self-healing in cementitious materials. The self-sealing leads to a regain in water tightness and promoted autogenous healing may prove to be useful to limit repair works caused by concrete cracking. By providing sufficient building blocks for healing, limiting the crack width by means of synthetic microfibers and inducing water by means of SAPs, a smart cementitious material is obtained. This material can be an excellent material to use in future building applications such as tunnel works and ground-retaining structures. This paper gives an overview of the current status of the research on SAPs in cementitious materials to obtain sealing and healing.

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Combined effect of expansive and shrinkage reducing admixtures to control autogenous shrinkage in self-compacting concrete

Construction and Building Materials ◽

10.1016/j.conbuildmat.2013.11.033 ◽

2014 ◽

Vol 52 ◽

pp. 267-275 ◽

Cited By ~ 44

Author(s):

Miguel José Oliveira ◽

António Bettencourt Ribeiro ◽

Fernando G. Branco

Keyword(s):

Autogenous Shrinkage ◽

Combined Effect ◽

Self Compacting Concrete ◽

Shrinkage Reducing Admixtures

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Discussing Different Approaches for the Time-Zero as Start for Autogenous Shrinkage in Cement Pastes Containing Superabsorbent Polymers

Materials ◽

10.3390/ma12182962 ◽

2019 ◽

Vol 12 (18) ◽

pp. 2962 ◽

Cited By ~ 5

Author(s):

José Roberto Tenório Filho ◽

Maria Adelaide Pereira Gomes de Araújo ◽

Didier Snoeck ◽

Nele De Belie

Keyword(s):

Transition Point ◽

Setting Time ◽

Autogenous Shrinkage ◽

Strain Curve ◽

Cementitious Materials ◽

Internal Curing ◽

Superabsorbent Polymers ◽

Time Zero ◽

Autogenous Strain ◽

Curing Agents

Many studies have already been published concerning autogenous shrinkage in cementitious materials. Still, no consensus can be found in the literature regarding the determination of the time-zero to initiate the recording of autogenous shrinkage. With internal curing agents, a correct evaluation of their efficiency depends on an appropriate choice of the time-zero. This study investigates different approaches to estimate the time-zero for cement paste mixtures with and without superabsorbent polymers as internal curing agents. The initial and final setting times were determined by an electronic Vicat and ultrasonic pulse velocity measurements (UPV); the transition point between the fluid and solid state was determined from the autogenous strain curve; the development of the capillary pressure was also studied. The choice of time-zero before the transition point led to higher values of shrinkage strain that should not be taken into account for autogenous shrinkage. A negligible difference was found between the strains when the final setting time and the transition point were taken as time-zero. Considering the artefacts and practical issues involving the different methods, the use of the transition point from the autogenous strain curve is the most suitable technique for determining the time-zero.

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Autogenous Shrinkage in High Performance Concrete with Chemical Admixtures

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.711.143 ◽

2016 ◽

Vol 711 ◽

pp. 143-149

Author(s):

Jennifer Anette Canul-Polanco ◽

Alejandro Durán-Herrera ◽

Pedro Valdez-Tamez

Keyword(s):

Corrosion Inhibitor ◽

Silica Fume ◽

High Performance ◽

High Performance Concrete ◽

Autogenous Shrinkage ◽

Superabsorbent Polymers ◽

Concrete Deterioration ◽

Chemical Admixtures ◽

Calcium Nitrite ◽

Shrinkage Reducing Admixtures

Durability in High Performance Concrete have resulted in the development of admixtures to mitigate several concrete deterioration mechanisms. Due to the low water/binder, HPC enables autogenous shrinkage that could lead to cracks at early ages. Superabsorbent polymers, shrinkage reducing admixtures and corrosion inhibitor based on calcium nitrite were used in HPC with silica fume to evaluate autogenous shrinkage. SAP was added with an amount of intenal curing water determined by the modification proposed by Jensen to the Power’s Model. Results showed that admixtures could improve or aggravate autogenous shrinkage.

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The Contribution of Elastic Wave NDT to the Characterization of Modern Cementitious Media

Sensors ◽

10.3390/s20102959 ◽

2020 ◽

Vol 20 (10) ◽

pp. 2959 ◽

Cited By ~ 2

Author(s):

Gerlinde Lefever ◽

Didier Snoeck ◽

Nele De Belie ◽

Sandra Van Vlierberghe ◽

Danny Van Hemelrijck ◽

...

Keyword(s):

Mechanical Performance ◽

Autogenous Shrinkage ◽

Measuring Method ◽

Cementitious Materials ◽

Mechanical Tests ◽

Self Healing ◽

Destructive Testing ◽

Superabsorbent Polymers ◽

Non Destructive

To mitigate autogenous shrinkage in cementitious materials and simultaneously preserve the material’s mechanical performance, superabsorbent polymers and nanosilica are included in the mixture design. The use of the specific additives influences both the hydration process and the hardened microstructure, while autogenous healing of cracks can be stimulated. These three stages are monitored by means of non-destructive testing, showing the sensitivity of elastic waves to the occurring phenomena. Whereas the action of the superabsorbent polymers was evidenced by acoustic emission, the use of ultrasound revealed the differences in the developed microstructure and the self-healing of cracks by a comparison with more commonly performed mechanical tests. The ability of NDT to determine these various features renders it a promising measuring method for future characterization of innovative cementitious materials.

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The influence of superabsorbent polymers on the autogenous shrinkage properties of cement pastes with supplementary cementitious materials

Cement and Concrete Research ◽

10.1016/j.cemconres.2015.03.020 ◽

2015 ◽

Vol 74 ◽

pp. 59-67 ◽

Cited By ~ 115

Author(s):

D. Snoeck ◽

O.M. Jensen ◽

N. De Belie

Keyword(s):

Autogenous Shrinkage ◽

Cementitious Materials ◽

Supplementary Cementitious Materials ◽

Superabsorbent Polymers ◽

Cement Pastes

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The Behavior of Superabsorbent Polymers (SAPs) in Cement Mixtures with Glass Powders as Supplementary Cementitious Materials

Materials ◽

10.3390/ma12213597 ◽

2019 ◽

Vol 12 (21) ◽

pp. 3597

Author(s):

Khashayar Farzanian ◽

Babak Vafaei ◽

Ali Ghahremaninezhad

Keyword(s):

Freeze Drying ◽

Setting Time ◽

Autogenous Shrinkage ◽

Cementitious Materials ◽

Supplementary Cementitious Materials ◽

Chemical Compositions ◽

Superabsorbent Polymers ◽

Flow Test ◽

Glass Powders ◽

Cement Mixtures

The absorption and desorption of superabsorbent polymers (SAPs) in cement mixtures containing two different glass powders as supplementary cementitious materials are examined in this paper. Two SAPs with different chemical compositions were synthesized in-house and used in the experiments. SAP absorption was investigated directly through the mass change of SAPs in cement slurries, as well as indirectly using the flow test. Scanning electron microscopy was used to monitor the desorption of SAPs using samples prepared with freeze-drying. Hydration and setting time were evaluated to explain the desorption behavior of SAPs. SAP absorption generally increased in pastes with glass powders. The desorption rate of SAPs in different pastes was shown to correlate with the onset of solid skeleton development in the pastes. The addition of SAPs reduced autogenous shrinkage in neat cement paste more than in pastes with glass powders.

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