Leveraging incinerator bottom ash for mitigating early age shrinkage in 3D printed engineered cementitious composites
Jie Yu, Fengming Xu, Hanghua Zhang, Junhong Ye, Jiangtao Yu, Jian‐Guo Dai, Yiwei Weng
Abstract
This study investigates the use of incinerator bottom ash (IBA) as a supplementary cementitious material to mitigate early age shrinkage in 3D printed engineered cementitious composites (3DP-ECC). IBA was processed through milling and thermal treatment before incorporation into 3DP-ECC. The fresh and hardened properties, hydration kinetics and products, early age shrinkage, and microstructural characteristics of 3DP-ECC with IBA were evaluated. Results indicate that pre-treated IBA reduces autogenous shrinkage and plastic shrinkage by 56 % and 30 %, respectively. The substitution of IBA increases the volume fraction of macropores (>1000 nm) of 3DP-ECC at 3 days and 7 days by approximately 300 % and 500 %, respectively, alleviating early age shrinkage. Sustainability analysis reveals that the incorporation of IBA can reduce the normalized embodied energy and carbon footprint of 3DP-ECC by over 17 %. These findings provide a promising approach to utilizing waste materials in mitigating early age shrinkage in 3DP-ECC towards sustainable digital construction.