Creep of alkali-activated cement mixtures

Hojati, Maryam; Rajabipour, Farshad; Radlińska, Aleksandra

doi:10.1016/j.cscm.2022.e00954

Cited by 3 publications

(4 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This might involve reducing the binder content (i.e., both precursors and activators), reducing the proportion of GGBS in the binder and replacing that with other alternatives (e.g., FA). Hojati et al (2022) reported lower creep values as the FA content increased in GGBS and FA-based AAC. Wardhono et al (2017) showed that FA-based AAMs experienced a stable increase in fc and Ec over a 540-days period, whereas their GGBS-based counterparts experienced significant deterioration in mechanical properties over the same period.…”

Section: Creep Measurementsmentioning

confidence: 91%

“…In cases where low-calcium precursors are used, such as fly ash-based AAMs, the creep response is typically lower than that of conventional concrete materials (CCMs) (Castel et al 2016;Gunasekera et al 2019;Sagoe-Crentsil et al 2013). However, in cases where high-calcium precursors are used, such as ground granulated blast furnace slag-based systems, the creep response is usually higher than that of CCMs (Collins and Sanjayan 1999;Hojati et al 2022;Ma and Dehn 2017). Low-calcium systems form N-A-S-H (sodium-aluminum-silicate-hydrate) gels, while their high-calcium counterparts mainly form C-A-S-H (calcium-aluminum-silicate-hydrate) gels, and their response under sustained load is significantly different.…”

Section: Introductionmentioning

confidence: 99%

“…It should be noted however that the creep deformations of concrete specimens are highly sensitive to the mix proportions and stress level, and future studies are needed to shed light on the response of OP-RuAAC under different conditions to those considered in this study. The creep response of concrete materials is also sensitive to the curing environment(Hojati et al 2022) and further studies can highlight the effect of different curing regimes, including water curing and oven curing, on the creep response of OP-RuAAC. The relative humidity of specimens during testing does also influences the results, and such behaviour can be investigated to gain insights into the basic creep and drying creep under varying relative…”

mentioning

confidence: 99%

See 2 more Smart Citations

Creep Response of Rubberized Alkali-Activated Concrete

Elzeadani,

Bompa,

Elghazouli

2023

J. Mater. Civ. Eng.

View full text Add to dashboard Cite

This study examines the creep deformations and long-term strength properties of rubberised one-part alkali activated concrete with relatively high rubber contents, which have not been previously reported. The aluminosilicate precursors used in the mix design are blast furnace slag and fly ash, at a ratio of 4-to-1, while anhydrous sodium metasilicate is used as the solid activator. Crumb rubber particles are used to replace 30 and 60% by volume of the total natural aggregates, and a non-rubberised one-part alkali-activated concrete mix is also prepared for comparison purposes. The creep specimens are subjected to two levels of sustained loads, representing 10 and 20% of the 28-day compressive strength. The creep loads are applied after 28 days of ambient curing and creep deformations are monitored for a period of one year. The results clearly show a deterioration in mechanical properties with higher rubber content, regardless of the testing age. The compressive strength and elastic modulus of the unloaded and loaded creep specimens, tested at an age of 393 days, are generally lower than that observed for similar specimens tested at 28 days. The axial and lateral crushing strains of the specimens tested at 393 days are significantly higher than their counterparts tested at 28 days. The creep strains, measured over 365 days, increase as the applied stress level increases, but reduce with higher rubber content. The creep coefficients and specific creep values of the tested specimens over 365 days experience a reduction as the applied stress level increases, while the opposite is seen as the rubber content increases. The creep coefficients of rubberised one-part alkali-activated concrete are generally higher than those given by prediction models in various codes for conventional concrete. The rate of creep development is also more significant than conventional concrete and does not show signs of slowing down after 365 days of sustained loading.

show abstract

Section: Creep Measurementsmentioning

confidence: 91%

Section: Introductionmentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Creep Response of Rubberized Alkali-Activated Concrete

Elzeadani,

Bompa,

Elghazouli

2023

J. Mater. Civ. Eng.

View full text Add to dashboard Cite

show abstract

“…Both creep and shrinkage are the inherent time-variance characteristics of the material itself [ 1 ], which is an important content of concrete structure design and calculation, having significant impacts on the performance of concrete structural components and systems. Creep and shrinkage affect stress distribution, widespread cracking, and excessive deformation, most of which have adverse effects on the long-term properties, usability, and durability of concrete building structures [ 2 , 3 , 4 , 5 , 6 ]. In this case, more attention needs to be paid to creep and shrinkage when designing and constructing concrete structures, particularly long-span prestressed concrete structures [ 7 ].…”

Section: Introductionmentioning

confidence: 99%

Statistical Evaluation of CEB-FIP 2010 Model for Concrete Creep and Shrinkage

et al. 2023

View full text Add to dashboard Cite

An extensive experimental database consisting of 2838 shrinkage data points and 3598 creep data points is used to evaluate the accuracy of the newly proposed CEB-FIP 2010 model in predicting the creep and shrinkage of concrete structures. To study the applicability of the model for high-strength concrete in general environments, the database was developed by only retaining the test data of concrete components with the average compressive strength greater than 30 MPa and the relative humidity in the test environment less than 95%. On this basis, combined with the B3 and CEB variation coefficient methods, the paper mainly adopts the residual method to assess the accuracy of the CEB-FIP 2010 model and compare it with the previous model, CEB-FIP 1990. The influences of several properties, such as the compressive strength, the age of concrete, the relative humidity, and the component size on the prediction accuracy of these two models are further studied. The results show that for the CEB-FIP 2010 model within the time interval of 0–9000 days, 52% and 48% of the shrinkage strain residuals of the total specimens are located in the negative and positive regions, respectively, while the positive and negative regions of the CEB-FIP 1990 model account for 73% and 27%, demonstrating the CEB-FIP 2010 model has better performance in predicting shrinkage strain than the CEB-FIP 1990 model, whereas the two models have comparable accuracy in predicting creep compliance. The CEB-FIP 2010 model is more reliable for considering the effects of compressive strength, relative humidity, and age at loading on shrinkage and creep than for considering the effect of member size.

show abstract