Effect of expansion agent on properties of self-compacting concrete under summer environment
YANG Lu
Abstract：To study the influence of typeⅡcalcium sulfoaluminate-calcium oxide composite expansion agent on expansion effi-ciency,compressive strength,durability,and volume stability of the SCC under different temperature conditions was compared.The results show that the expansion efficiency of the expansion agent could be stimulated when cured in the high temperature environ-ment for appropriate time,but the expansion efficiency will be lost if the environment temperature is too high.The expansion effi-ciency of the expansive agent cured at 20℃and 30℃environment is better,the compressive strength of SCC at the early age showed an upward trend,but the strength developed very slowly in the later period,electric flux and volume stability decreased significantly.The expansion efficiency of the expansion agent is significantly reduced under the curing conditions of 40℃and 50℃for more than 2 hours which cannot meet the requirements of type Ⅱ expansive agent in standard GB/T 23439-2017"Expan-sive agents for concrete".The drying shrinkage of self-compacting concrete cannot meet the requirements of Q/CR 596-2017"Specification of self-compacting concrete for high-speed railway CRTSⅢ slab ballastless track".It is recommended to carry out construction operations at night in summer.
Keywords：summer environmentself-compacting concreteexpansive agentexpansion efficiencyvolume stability
Publication Date：2025-12-25
Online Publishing Date：2026-01-13(First online date of this platform, not the publication date of the document)
Pages：4( 64-67 )