𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Moisture diffusion in cementitious materials Adsorption isotherms

✍ Scribed by Yunping Xi; Zdeněk P. Bažant; Hamlin M. Jennings

Publisher
Elsevier Science
Year
1994
Tongue
English
Weight
745 KB
Volume
1
Category
Article
ISSN
1065-7355

No coin nor oath required. For personal study only.

✦ Synopsis

This article describes an improvement on a previous model proposed by Ba~ant and Najjar, in which moisture diffusivity and moisture capacity are treated as separate parameters. These parameters are evaluated from independent test results, and are shown to depend on the water:cement ratio, curing time, temperature, and cement type. The moisture capacity is obtained as the slope of the adsorption isotherm. A mathematical model is developed and is shown to predict experimental adsorption isotherms of Portland cement paste very well. In the present form, the model is not applicable to high temperatures.

📜 SIMILAR VOLUMES

Moisture diffusion in cementitious mater
Moisture diffusion in cementitious materials Moisture capacity and diffusivity
✍ Yunping Xi; Zdenňek P. Bažant; Larissa Molina; Hamlin M. Jennings 📂 Article 📅 1994 🏛 Elsevier Science 🌐 English ⚖ 745 KB

Based on a model by Ba~ant and Najjar, and using a new model for adsorption isotherms, moisture capacity and diffusivity of concrete are analyzed. The moisture capacity, obtained as a derivative of the adsorption isotherm, first drops as the humidity increases from zero, then levels off as a constan

Diffusion in cementitious materials: II,
Diffusion in cementitious materials: II, further investigations of chloride and oxygen diffusion in well-cured OPC and OPC/30%PFA pastes
✍ VT Ngala; CL Page; LJ Parrott; SW Yu 📂 Article 📅 1995 🏛 Elsevier Science 🌐 English ⚖ 547 KB

Steady-state diffusion of dissolved oxygen and chloride ions in hydrated OPC and OPC/30%PFA pastes, hydrated for 2 weeks at 20°C and 10 weeks at 38°C was studied at water/binder (w/s) ratios 0.4, 0.5, 0.6 and 0.7. Total porosity and a simple measure of capillary porosity, the volume fractions of the