关键词: 地聚物, 混凝土, 收缩, 徐变

Abstract:

Geopolymer，with merits of high early strength，good thermostable performance and less environmental pollution，is a new inorganic cementing material involving intensive research both at home and abroad． It is very important to grasp the shrinkage and creep characteristics of geopolymer to determine whether it can be used to replace Portland Cement ( OPC) or not． The research of geopolymer on shrinkage and creep in recent years were reviewed in this paper focusing on the shrinkage and creep characteristics，mechanism and improvement measures of fly ash based geopolymer ( AAFA) and slag based geopolymer ( AAS) ． The results show that: AAFA has a larger shrinkage rate at room temperature，and AAFA cured at high temperature can obtain a smaller shrinkage rate than OPC; AAS shrinkage rate is much larger than OPC; the shrinkage mechanism of geopolymer is not exactly the same as that of OPC; the shrinkage of geopolymer can be reduced to a certain extent through properly raising the curing temperature，reducing the sodium content and adding fibers; the geopolymer concrete prepared with fly ash and appropriate amount of slag is a promising building material that can meet the requirements of strength and obtain a smaller dry shrinkage than OPC concrete; AAFA concrete has a smaller creep than OPC concrete，but AAS concrete has a larger creep than OPC concrete． In addition，the addition of a small amount of slag to AAFA has little effect on creep． The nano-indentation technology can be used to quickly and reliably evaluate the creep of geopolymer concrete． Finally，some suggestions for further research were put forward．

Key words: geopolymer, concrete, shrinkage, creep