The combined effect of distributing-filling aggregate process and air-entraining agent on the properties of aggregate-interlocking concrete

• Published in: Materials and structures 2022-09, Vol.55 (7), Article 201
• Main Authors: Cai, Jiwei, Du, Yun, Xu, Gelong, Shen, Weiguo, Tian, Qing, Zhang, Miao
• Format: Article
• Language: English
• Subjects: Air entrainment; Air-entraining admixtures; Building construction; Building Materials; Civil Engineering; Compressive strength; Concrete aggregates; Distributing; Engineering; Flexural strength; Frost resistance; Locking; Machines; Manufacturing; Materials Science; Mechanical properties; Original Article; Penetration depth; Penetration resistance; Processes; Scaling; Sodium chloride; Solid Mechanics; Storage modulus; Theoretical and Applied Mechanics
• ISSN: 1359-5997; 1871-6873
• DOI: 10.1617/s11527-022-02043-2

In order to find an effective approach to improve the frost resistance of aggregate interlocking concrete, the effect of air-entraining agent (AEA) on the mechanical properties and durability of aggregate interlocking concrete prepared via the distributing-filling coarse aggregate (DFCA) process is investigated in this study. The DFCA process improves the compressive and flexural strength, elastic modulus and penetration resistance, but the non-air-entrained DFCA concrete presents worse frost resistance than the conventional concrete in accordance with the results of relative dynamic elastic modulus, scaling mass, mass of absorbed water, and penetration depth of NaCl solution. A larger DFCA ratio leads to a greater reduction in mechanical properties of air-entrained DFCA concrete, which is more pronounced for compressive strength than for flexural strength and elastic modulus. AEA enhances the frost resistance of DFCA concrete with respect to the relative dynamic elastic modulus, but the scaling test indicates that the excessive air entrainment is deleterious to the frost resistance of concrete with high coarse aggregate concentration. The initial water uptake and penetration depth of NaCl solution increase as the air-entraining agent increases. The severer scaling generally happens on the concrete with a higher initial water uptake, while the water uptake rate becomes slow for the concrete with a larger scaling rate. Overall, with the appropriate DFCA ratio and AEA dosage, it is feasible to prepare the air-entrained DFCA concrete with comparable mechanical properties and better frost resistance in comparison with the conventional concrete.