en Research Paper Research Paper Shrinkage behavior of a geopolymer cement paste prepared from pumice-type natural pozzolan was studied<br>by changing parameters of chemical composition including SiO2/Na2O molar ratio of activator and total molar ratios<br>of Na2O/Al2O3, and H2O/Al2O3. For investigating the effect of curing conditions on shrinkage, hydrothermal curing<br>was also applied. The obtained results clearly revealed the governing effect of chemical composition on shrinkage.<br>Mixes with different Na2O/Al2O3 molar ratios exhibited different shrinkage behavior due to variations made in<br>SiO2/Na2O molar ratio. Application of hydrothermal curing after a 7-day period of precuring in humid atmosphere<br>also showed strong effect on shrinkage reduction. Geopolymer cement, Shrinkage, Chemical Composition, Curing, Natural Pozzolan 50 60 http://ijmse.iust.ac.ir/browse.php?a_code=A-10-3-157&slc_lang=en&sid=1 E. Najafi Kani 180031947532846001242 180031947532846001242 No A. Allahverdi ali.allahverdi@iust.ac.ir 180031947532846001243 180031947532846001243 Yes