Rheological behaviors and viscosity prediction model of cementitious composites with various carbon nanotubes

This study aims to understand the effects and mechanisms of length, diameter, and functional group of carbon nanotubes (CNTs) on rheological behaviors of cementitious composites. The experimental results show that the addition of CNTs decreases the flow index and increases the critical shear rate of cementitious composites. CNTs with a sub...

Nanomechanical Characteristics of Interfacial Transition Zone in Nano-Engineered Concrete

This study investigates the effects of nanofillers on the interfacial transition zone (ITZ) between aggregate and cement paste by using nanoindentation and statistical nanoindentation techniques. Moreover, the underlying mechanisms are revealed through micromechanical modeling. The nanoindentation results indicate that incorporating...

Multivariate data assimilation of GRACE, SMOS, SMAP measurements for improved regional soil moisture and groundwater storage estimates

Assimilating remote sensing observations into land surface models has become common practice to improve the accuracy of terrestrial water storage (TWS) estimates such as soil moisture and groundwater, for understanding the land surface interaction with the climate system, as well as assessing regional and global water resources. Such remote...

A novel capsule-based selfrecovery system with a chloride ion trigger

Steel is prone to corrosion induced by chloride ions, which is a serious threat to reinforced concrete structures, especially in marine environments. In this work, we report a novel capsule-based selfrecovery system that utilizes chloride ions as a trigger. These capsules, which are functionalized via a smart response to chloride ions, are...

The effect of processing parameters on the formation of epoxy/UF resin microcapsules

Epoxy E-51/UF resin microcapsules were prepared by traditional two-stepped in situ polymerization method and processing parameters affecting the final microcapsules’ shape and size were carefully studied in the aim to obtain microcapsule with ideally spherical shape and uniform size. It’s found the polycarboxylate surfactant of SMA (styrene...

Preparation of mono-sized epoxy/MF microcapsulesin the appearance of polyvinyl alcohol as co-emulsifier

For epoxy microcapsules embedded in concrete as mechanic-triggered self-healing adhesive, globular shape with uniform size is the basic requirement to ensure the solid shell broken and the liquid core released at a designed stress. In this paper, monodispersed melamine–formaldehyde (MF) resin-walled epoxy E-51 microcapsules were successfully...

Preparation and characterization of poly (urea-formaldehyde) walled dicyclopentadiene microcapsules

Poly (urea-formaldehyde) (PUF) shelled dicyclopentadiene (DCPD) microcapsules were prepared by in-situ polymerization technology for self-healing concrete applications. It’s found, during the process, sodium dodecyl benzene sulfonate (SDBS) behaves better in emulsification of DCPD than other surfactant of sodium lauryl sulfate (SLS) and styrene...

The smart releasing behavior of a microcapsule based on chemical self-healing system caused by chemical trigger activation

A novel chemical self-healing system based on microcapsule technology for cementitious composites is established in Guangdong Key Laboratory of Durability for Coastal Civil Engineering, Shenzhen University. The key issue of this system is how to release the healing material and how to activate the healing mechanism. In this paper, the study is...

Preparation and characterization of poly (urea-formaldehyde) walled dicyclopentadiene microcapsules

Poly (urea-formaldehyde) (PUF) shelled dicyclopentadiene (DCPD) microcapsules were prepared by in-situ polymerization technology for self-healing concrete applications. It’s found, during the process, sodium dodecyl benzene sulfonate (SDBS) behaves better in emulsification of DCPD than other surfactant of sodium lauryl sulfate (SLS) and styrene...

A study on the steel corrosion protection of a microcapsule based self-healing cementitious system by means of electrochemical impedance spectroscopy

Based on microcapsule technology, a new type of self-healing system for cementitious composites is established. The performance of the system was characterized by means of electrochemical impedance spectroscopy of steel bars immersed in a simulated concrete environment. The results demonstrate strong inhibition of chloride-induced corrosion when...

Self-encapsulation of epoxy resin by a controlled interface curing process in epoxy/water emulsion

The microcapsules of epoxy E-51 resin encapsulated by cured itself were prepared by interfacial curing reaction, in which ethylenediamine (EDA) was employed as curing agent and sulfonated copolymer of styrene and maleic anhydride (SMA) as emulsifying agent. It’s found the morphology of microcapsules strongly depend on reaction time and EDA...