Portland cement microsilica-modified

An exposme to elevated temperature (up to 600°C) tends to increase the strength of microsilica-modified Portland cement based concrete. This may be attributed to the formation of additional C-S-H in a reaction between residttal calcium hydroxide and microsilica (Saad et al, 1996). 

The use of microsilica-modified Portland cement concrete may be indicated especially in applications where reduced permeability and high chemical resistance of the material are required. The use of this material is also essential in making concrete of extremely high strength. Compressive strengths exceeding 100 MPa may be obtained under these conditions. 

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