Expansive agents, such as calcium sulfo-aluminate expansive admixtures, have been applied to compensating the shrinkage of cement widely. However, wet curing is prerequisite for their expansion, thus their application in many concrete structures without enough moisture is limited. A new expansive agent, MgO-based expansive agent (MEA) is added into three kinds of cements to prepare cylindrical pastes. The pastes are sealed by plastic membrane to prevent the inner moisture from transferring into exterior environment, and temperature of the specimens is controlled by a curing box to simulate temperature development in field concrete. Deformations of those cement pastes were test, and the autogeneous shrinkage was also calculated by removing thermal deformation. Results show that, even under the non-wet condition, shrinkage of cement pastes can be compensated effectively by MEA. What's more, it is also effective for the compensation of thermal shrinkage at late age.
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