Open Access

Effect of air-cooled blast furnace slag aggregates on the autogenous shrinkage of concrete

Aiguo Wang¹, Yi Zheng¹, Peng Liu^2,*, Jun Zhao¹, Kaiwei Liu¹, Yueming Wang¹, Daosheng Sun^1,*
1 The Key Laboratory of Advanced Civil Engineering Materials of Anhui Province, Anhui Jianzhu University, Hefei, 230601, China
2 College of Materials Science and Engineering, Nanjing Tech University, Nanjing, 211800, China
* Corresponding Author: Peng Liu. Email: ; Daosheng Sun. Email:

ZKG International https://doi.org/10.32604/zkg.2025.074609

Received 14 October 2025; Accepted 22 December 2025; Published online 14 January 2026

Abstract

Autogenous shrinkage is one of the primary factors leading to cracking in concrete structures. To enhance the efficiency of solid waste resource utilization, this study utilizes air-cooled blast furnace slag aggregates (ACBFSAs) to prepare concrete. The impact of different combinations of coarse and fine aggregates (NS-LCR, NS-SCR, SS-LCR, and SS-SCR) on the autogenous shrinkage of concrete is investigated. The experimental results indicate that the shape of the ACBFSAs is more irregular, and the surface of the aggregates is rougher. The 112 d autogenous shrinkage of the NS-LCR group reaches −195.4 μm/m. Replacing natural aggregates with ACBFSAs effectively reduces the autogenous shrinkage of concrete, and the SS-SCR group even exhibits micro expansion (55.8 μm/m). Owing to the internal curing effect induced by ACBFSAs, the concretes obtain higher internal relative humidity and smaller autogenous shrinkage. Its multi-angular characteristics and rough surface greatly increase the bonding strength between aggregate and the matrix. This study can provide technical support for the resource utilization of ACBFSAs in concrete.

---

Keywords

Air-cooled blast furnace slag aggregate; morphological characteristics; autogenous shrinkage; shrinkage reduction mechanism

---