Revealing the dark side of Portlandite Clusters in cement paste by circular polarization microscopy

Plane and crossed polarization are the two standard light modes in polarized light microscopy that are widely used to characterize crystalline and amorphous phases in cement-based materials. However, the use of the crossed polarized light mode has been found to be restrictive for studying birefringent phases quantitatively due to the extinction...

How to measure path length?

Path length measuring is a relevant engineering problem. Leonardo Da Vinci designed for the military appropriate equipment, the podometer, to do so. Modern equipment such as step meters and map meters are quite similar to Da Vinci?s design, despite geometrical statistical - stereological - methods based on theorems of Cauchy and Buffon that were...

The ITZ in concrete with natural and recycled aggregates: Study of microstructures based on image and SEM analysis

Aim of this work was to investigate the microstructure of the Interfacial Transition Zone (ITZ) between cement paste and aggregate in concrete utilizing Scanning Electron Microscope (SEM) in order to identify possible effects on the ITZ related to different recipes and production parameters. SEM is an important tool to carry out concrete, cement...

Mechanical, electrical and microstructural properties of cement-based materials in conditions of stray current flow

This investigation presents a comparative study on mechanical properties, electrical resistivity and microstructure of mortar under DC current, compared to mortar in rest (no current) conditions. Monitoring was performed from 24h after casting until 84 days of cement hydration. A current density level of 10 mA/m2 was chosen as a simulation...

Effect of Admixed Micelles on the Microstructure Alterations of Reinforced Mortar Subjected to Chloride Induced Corrosion

This paper reports the main results from the influence of the initially admixed nano-aggregates (0.5 g/l PEO113-b-PS70 micelles previously dissolved in demi-water) on microstructural alterations of the reinforced mortar subjected to chloride induced corrosion. The morphology of hydration/corrosion products at the steel/cement paste interface and...