CVG 2141 Lecture Notes - Lecture 5: Epoxy, Concrete Cover, Stainless Steel

• School: University of Ottawa
• Department: Civil Engineering
• Course: CVG 2141
• Professor: Abdulridha Alaa

Document Summary

Is the resistance to weathering by chemicals, abrasion, deterioration. Porosity: caused by improper consolidation and the evaporation of excess water unused for hydration. Influencing factors: w/c ratio, rate of hydration, curing, aggregate size, grading, shrinkage deterioration. Cement paste has a higher permeability coefficient than concrete. Chemical: alkali-agg reactions (asr or acr, chem reaction b/w minerals in aggregates and alkalis in pc), sulphate attack, reinforcement corrosion: alkali-aggregate reactions: needs reactive components in agg. Can be minimized by using non reactive aggregates and low alkali cement. Occurs when sulphate ions (from environment) penetrates the concrete and reacts with hydrated c3a. Causes volume expansion, internal stresses, scaling and cracking. Can be minimized by using cement with low c3a (ms or hs), low w/c, mineral admixtures (w/o. Caused by electrochemical processes with the presence of oxygen and moisture. Causes cracking in the concrete and mass loss (pitting) of the bar can also cause the bar to rupture, spalling.