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Portland cement (PC)-metakaolin (MK) pastes of compositions 0, 5, 10, 15, 20 and 25% MK and water/binder ratio 0·55 have been subjected to tests for chemical shrinkage, autogenous shrinkage and expansion during soaking. Chemical shrinkage was carried out in 200 ml containers on water-covered 12 mm thick layers of paste, and the volume changes were monitored using 1 ml graduated pipettes. Autogenous shrinkage and expansion were determined by monitoring the dimensional changes of 285 × 25 × 25 mm paste bars, in, respectively, a sealed environment and in water. Volume changes are converted to millilitres per gram of binder for all three systems for purposes of comparison. Chemical shrinkage was found to increase for compositions between 0 and 15% MK and then decrease for compositions above 15% MK. Autogenous shrinkage was found to increase for compositions between 0 and 10% MK …