Certification of SRM 2492: Bingham Paste Mixture for Rheological Measurements As measurements with rheometers can involve flow in a complex geometry, it is important that they are calibrated with a standard reference material (SRM). NIST has produced a Standard Reference material for paste (SRM 2492) as the first step for the development of a reference material for concrete rheometers. The process used to develop both the SRM 2492 and the mortar reference material is presented, including measurements, statistical analyses, and modeling. The developed SRM consists of a mixture of two components, corn syrup and fine limestone and has the texture of cement paste.
Publisher: Chiara F. Ferraris; Paul E. Stutzman; William F. Guthrie; National Institute of Standards and Technology (NIST), 2012 Registered on: Feb 3, 2014 | Category: Materials Testing: Rheology
Time reverse modeling of acoustic emissions in structural concrete Details on acoustic emission (AE). An often used application of AE analy-
sis is the localization of concrete cracks and reinforcement ruptures.
However, for progressed crack patterns, common localization procedures fail, because the waves have either been reflected repeatedly or experienced interference
with other waves. In this dissertation a new method of AE analysis
is developed which takes advantage of the wave field interferences. Publisher: Dissertation. Kocur, Georg Karl. Swiss Federal Institute of Technology Zurich, Institute of Structural Engineering (2012) Registered on: Feb 1, 2014 | Category: Materials Testing: Acoustic Emission Analysis
Working mechanism of various cellulose ethers as water retention admixtures in oil well cementing and in dry-mix mortar systems The doctoral dissertation includes three papers: (1) "Role of Colloidal Polymer Associates for the Effectiveness of Hydroxyethyl Cellulose as a Fluid Loss Control Additive in Oil Well Cement". Journal of Applied Polymer Science, Vol. 126, E25–E34 (2012). (2) "Mechanistic Study on Carboxymethyl Hydroxyethyl Cellulose as Fluid Loss Control Additive in Oil Well Cement". Journal of Applied Polymer Science, Vol. 124, 2340–2347 (2012). (3) "Working mechanism of methyl hydroxyethyl cellulose (MHEC) as water
retention agent". Cement and Concrete Research 42 (2012) 953–959. Publisher: Daniel Bülichen, Dissertation, TU München, 2013 Registered on: Feb 1, 2014 | Category: Materials Science: Rheological additives
High strength concrete Report on investigations into the effects of setting and hardening on the properties of high strength concretes, and in particular on the behaviour with restrained deformation at a young age. The shrinkage (in particular the autogenous shrinkage) as well as the release of heat of hydration and the associated strength development were investigated. [12 pages, 597 kB, PDF] Publisher: Maria Teresa Alonso Registered on: Jul 4, 2005 | Category: Materials Science: Concrete
Mitigation Strategies for Autogenous Shrinkage Cracking The fundamental parameters contributing to the autogenous shrinkage and resultant early-age cracking of concrete are presented. Mitigation strategies which are discussed include: the addition of shrinkage-reducing admixtures more commonly used to control drying shrinkage, control of the cement particle size distribution, modification of the mineralogical composition of the cement, the addition of saturated lightweight fine aggregates, the use of controlled permeability formwork, and the addition of superabsorbent polymers ("water-entrained" concrete) . Publisher: Bentz, D. P.; Jensen, O. M., in: Cement and Concrete Research, Vol. 26, No. 6, 677-685, August 2004 Registered on: Mar 15, 2005 | Category: Materials Science: Shrinkage-reducing Additives