AUTHOR=Shi Peng , Li Zhen , Chen Xiaorun , Zeng Lei , Hu Rong 

TITLE=Effect of industrial waste molecular sieves on internally cured cement-based materials

JOURNAL=Frontiers in Materials

VOLUME=Volume 9 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/materials/articles/10.3389/fmats.2022.1003556

DOI=10.3389/fmats.2022.1003556

ISSN=2296-8016

ABSTRACT=Using waste molecular sieves (MS) instead of sand as water-absorbing fine aggregates in cement-based materials can effectively deal with factory adsorption waste and reduce sand consumption. In this paper, industrial waste molecular sieve is recycled and incorporated into cement - based materials. The effect of molecular sieve as a hydration internal curing agent on the performance of cement-based materials is studied. A series of experiments are designed to find out the appropriate ratio and to evaluate and analyze the internal curing effect of waste molecular sieves. Compressive strength, flexural strength and dry shrinkage properties of mortar with different dosage of molecular sieve are tested. And the water release behavior of molecular sieve in mortar is comprehensively analyzed combined with desorption test of molecular sieve. Results show that the compressive and flexural strength increase by 5% and 10%, the drying shrinkage decrease by 6% when 10% of sand is replaced by molecular sieve under the same total water content. The hydration behavior of the sample is characterized by microcosmic test of paste. Thermogravimetric analysis is used to calculate the content of corresponding hydration products and quantitatively describe the hydration degree of internal curing paste mixed with MS. Results show that the content of hydration products is improved by the addition of molecular sieve, which provide a theoretical basis for the enhancement of mortar to a certain extent.