Journal of the Chinese Ceramic Society, Volume. 53, Issue 3, 553(2025)

Research Progress on Chemical Admixtures for Improving Durability of Structural Concrete

CAI Jingshun1...2, LI Hua1,2, SHU Xin2, SHAN Guangcheng1,2, CHEN Jian2 and RAN Qianping1,* |Show fewer author(s)
Author Affiliations
  • 1Jiangsu Key Laboratory of Construction Materials, School of Material Science and Engineering, Southeast University, Nanjing 211189, China
  • 2State Key Laboratory of High Performance Civil Engineering Materials, Nanjing 210008, China
  • show less

    Concrete durability is recognized as a worldwide problem. With global warming and harsh service environment, the problem of premature failure of structural concrete durability becomes more prominent. Chemical admixtures as the key components of concrete show significant technical advantages in improving the microstructure and durability of structural concrete. This review represents research progress on the durability enhancement admixtures for the innovation of concrete durability enhancement technology and the development of low-carbon and sustainable society.Some admixtures used for concrete crack control (i.e., expanding agent, water evaporation inhibitor, heat of hydration inhibitor) are described. The addition of nanomaterials and polymers as well as the use of monomer in-situ polymerization are summarized. In addition, SAP, osmotic crystallization and expansion agents for realizing the self-healing of cracks are also discussed.Air entraining agent, pore hydrophobic agent and nano-pore compacting agent are summarized to enhance concrete microstructure, thus solving the durability failure problem of concrete under freeze-thaw, sulfate attack and chloride ion attack.Corrosion inhibitor is inducted. Recent research progress on organic rust inhibitors, green rust inhibitors and intelligent rust inhibitors is reviewed, and the existing problems of current rust inhibitors are summarized, and the development direction of future rust inhibitors is prospected.Summary and ProspectsDurability failure is a challenge facing the sustainable development of society. How to improve the durability of structural concrete with low cost and high efficiency is a key problem to be solved. This review represents the research progress on durability enhancing admixtures in concrete crack control, microstructure regulation and reinforcement rust resistance improvement, and points out the existing problems of various admixtures.1) Concrete crack control is a premise of structural concrete durability improvement. However, how to further improve the effectiveness and adaptability of admixtures according to the changes of concrete material system characteristics and environmental requirements is a major development direction. In addition, toughness enhancement and self-healing admixtures are still in the research stage, and the key properties are still unclear. How to realize the application needs, further reveal the structure-activity relationship of key materials and achieve the improvement of toughness and self-healing properties is a problem worthy of in-depth study.2) The control of concrete microstructure is a key to improving the durability of concrete. Air entraining agent, pore hydrophobic agent and nano-pore compacting agent are effective technical means to enhance concrete microstructure, which can solve the durability failure problem of concrete under freeze-thaw, sulfate attack and chloride ion attack. However, for coupled corrosion environment, there are still insufficient mutual adaptability of various admixtures applied together, and a further research is needed. In addition, the relations among air entrainment agent, pore hydrophobic agent, nano densifier, cement hydration, stable regulation/optimization of pore structure, and the resulting durability impact mechanism are still unclear, which need to be further investigated.3) The improvement of rust resistance of steel bars is a fundamental to the improvement of structural concrete durability. Inorganic and organic rust inhibitors are important components of rust inhibitors, and the reasonable use of different kinds of rust inhibitors is a key to achieve the improvement of rust resistance performance of steel bars in complex systems. The corrosion protection and repair of structural concrete can be improved via different application methods such as internal mixing, external coating, electromigration and pressure penetration. The future development direction of rust inhibitors can be green and intelligent, but it still needs to be further studied in combination with practical applications.Although the durability of concrete is extremely complex, admixtures have some technical advantages in improving the durability of concrete. In the future, it is necessary to further analyze the micro-action mechanism and structure-activity relationship of admixtures, and propose an effective method of structural design and preparation of admixtures by theoretical calculation (i.e., molecular simulation, artificial intelligence and other theoretical analysis). Also, slow and controlled release technologies such as microcapsule coating, layered and porous material loading are used with the characteristics of cement hydration to enhance the durability and improve the adaptability of admixtures to cement concrete, thus realizing the efficient use of admixtures in concrete systems at regular and fixed points, avoiding the influence of admixtures on cement hydration, microstructure formation and long-term performance,and achieving an accurate control of structural concrete durability throughout the life cycle.

    Tools

    Get Citation

    Copy Citation Text

    CAI Jingshun, LI Hua, SHU Xin, SHAN Guangcheng, CHEN Jian, RAN Qianping. Research Progress on Chemical Admixtures for Improving Durability of Structural Concrete[J]. Journal of the Chinese Ceramic Society, 2025, 53(3): 553

    Download Citation

    EndNote(RIS)BibTexPlain Text
    Save article for my favorites
    Paper Information

    Special Issue:

    Received: Jul. 31, 2024

    Accepted: Mar. 10, 2025

    Published Online: Mar. 10, 2025

    The Author Email: Qianping RAN (qpran@cnjsjk.cn)

    DOI:10.14062/j.issn.0454-5648.20240504

    Topics