Use of supplementary cementitious materials
Posted by Gretchen from Socorro, NM, US on March 8, 2007
Im interested in historical data for usage of pozzolans and other scms in concrete. What Im looking for is production or consumption data for concrete containing fly ash, ggbfs, natural pozzolans or silica fume (in the U.S.). Do you have any suggestions where I might find this information? Thank you for time.
Finding the consumption of the pozzolanic materials you mentioned above would be easy, but information on the consumption of concrete containing these materials is difficult.
There is an association for all SCM’s, you can try contacting them for this information. You can contact the “Slag cement association” (http://www.slagcement.org/), Silica Fume association” (http://www.silicafume.org/) and “American Coal Ash association” (http://www.acaa-usa.org/default.htm).
Also, approximately 75% of the concrete in United States is produced by Ready mix Concrete companies. You can contact the National Ready mix concrete association (NRMCA) and ask if they maintain such data.
Also, there are market research companies who do such kinds of research within the construction industry, you can approach such firms.
hight range water reducer.
Posted by Fafa from Tunis, OT, TN on March 7, 2007
How can we decide if a chemical ptoduct can be used as a hight range water reducer?
As the Sodium Tripolyphosphate is used to modify or to enhance the reological proprities of the clay; can we use it for cement pastes? And how can we study its effects on the concrete behavior ( at early age and hardening time)?
Any chemical admixture to qualify as a high range water reducer (HRWR) has to meet the requirements stated in ASTM C 494. The most widely used HRWR’s are based on Sulphonated naphthalene formaldehyde (SNF), Sulphonated melamine formaldehyde (SMF), Polycarboxylate admixtures (PC) and Modified Lignosulphonates.
The common fresh and hardened properties studied on concrete using admixtures are, slump (workability), slump retention, compressive strength, set time, air entrainment, freeze thaw, shrinkage etc.
I do not have any information on the use of Sodium Tripolyphosphate on cements.
