Effect of Absorbent Polymer Balls (APBs) with Varying Contents on the Mechanical and Shrinkage Properties of Internally Cured

The purpose of this study was to investigate how the different dosages and methods of introducing Absorbent Polymer Balls (APBs) affect the characteristics of the mixture. Unlike other research that concentrate only on the dosage of APBs, the current research also pays attention to another critical variable - the method of introducing the APBs. Three methods of incorporating the mixture included pre-soaking (Soaking of APBs in water prior to the mixing), dry mixing (Mixing of APBs with dry components before water addition), and surface coating (Application of a thin layer of cement paste on APBs particles), each involving different dosages of APBs ranging from 0.5 to 5.0% of cement mass. Workability, compressive strength, split tensile strength, and the rate of drying shrinkage after 90 days were analysed. It has been shown that the most effective in terms of moisture regulation is the pre-soaked method of incorporation. The highest compressive strength (42 MPa) and the minimum shrinkage (430 με) were achieved when the dose was 4.0%. On the other hand, tensile strength was maximum at the dosage level of 2.0% (4.8 MPa). As can be seen from the above findings, both dosage and method of introduction affect densification.