Effects of Nano-MgO on Expansion and Strength of Hardened Cement Pastes
YE Qing
YU Shenghua
ZHANG Zenan
ZHANG Qiang
SHI Tao
Abstract：The variation of expansion and compressive strength of hardened cement paste with nano-MgO added was studied compared with that for light-burnt MgO.Results indicate that nano-MgO and light-burnt MgO in the paste are hydrated after the test of cement autoclave soundness,and their qualified maximum for soundness is about 10％ and 4％(by mass) respectively.Cured in water at 40 ℃ till 730 days,both nano-MgO and light-burnt MgO in pastes are hydrated,paste expansions increase with the increase of MgO and curing time,and the paste expansion added with nano-MgO tend to be stable more easily than that with light-burnt MgO.Meanwhile,the paste compressive strengths increase with the increase of nano-MgO,but decrease with the increase of light-burnt MgO.For cement-based materials,nano-MgO has advantages of higher soundness and higher stability for strength as compared with light-burnt MgO.The results suggest that expansions from nano-MgO hydration may be used to compensate the shrinkage of mass concrete.
Keywords：hardened cement pastenano-MgOlight-burnt MgOexpansionstrength
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：5( 765-769 )