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Chapter 4. Working with Silica-Fume Concrete. Conducting a Test Placement Transporting, Placing, and Consolidating Finishing Flatwork Finishing Bridge Decks Preventing Plastic-Shrinkage Cracking Curing. Conducting a Test Placement. Chapter Outline.
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Chapter 4. Working with Silica-Fume Concrete • Conducting a Test Placement • Transporting, Placing, and Consolidating • Finishing Flatwork • Finishing Bridge Decks • Preventing Plastic-Shrinkage Cracking • Curing
Conducting a Test Placement Chapter Outline
Remember:Silica-fume concrete is more cohesive and less prone to segregationTo improve workability, increase slump by about 2 in. (50 mm)
Transporting, Placing, and Consolidating Silica-Fume Concrete Chapter Outline
Finishing Silica-Fume Concrete Flatwork Chapter Outline
Click on the icon above to play a video on finishing silica-fume concrete
Under Finish Silica-Fume ConcreteUse the “One-Pass” Technique
One-Pass Finishing • Screed • Float • Texture • Cure Protect, Protect, Protect!
Broomed surface -- all that is required for a parking structure
Finishing Silica-Fume Concrete Bridge Decks Chapter Outline
Preventing Plastic Shrinkage Cracking Chapter Outline
What is Plastic Shrinkage Cracking? Cracking that occurs in the surface of fresh concrete soon after it is placed and while it is still plastic. -- ACI 116R
Silica fume concrete does not bleed and is more susceptible to plastic shrinkage cracking
Curing Silica-Fume Concrete Chapter Outline
“If silica-fume concrete mixtures are given 7 days of continuous moist curing, then there is no association between silica fume content and cracking.” -- Whiting and Detwiler NCHRP Report 410
“It is recommended that a minimum of 7 days continuous moist curing be specified.” -- Whiting and Detwiler NCHRP Report 410