Buckling of Columns – Euler Theory for Elastic Buckling

Buckling of Concrete Columns

Buckling of Columns – Euler Theory for Elastic Buckling BUCKLING – Loss of stability –Axial loads cause lateral deformations (bending-like deformations) Buckling of Columns is a form of deformation as a result of axial- compression forces. This leads to bending of the column, due to the instability of the column. This mode of failure is … Read more

Freeze Thaw Damage of Concrete – Effects & Preventive Measures

Damage of Bridge due to Freeze Thaw Cycles

Freeze Thaw Damage of Concrete – Effects & Preventive Measures “damage to concrete caused by extreme temperature variations as noted by random pattern cracking.” A severe exposure condition on portland cement concrete structures is exposure to cycles of freezing and thawing. Air entrainment is used to enhance the freeze-thaw resistance of portland cement concrete exposed … Read more

Significance of Delayed Ettringite Formation and Damage Mechanisms

Cracks due to delayed ettringite formation

Significance of Delayed Ettringite Formation and Damage Mechanisms Ettringite is formed in hydrated Portland cement system as a result of the reaction of calcium aluminate with calcium sulfate, both present in Portland cement. In the cement system, the presence of ettringite depends on the ratio of calcium sulfate to tri-calcium aluminate (C3A); when this ratio … Read more

D-Cracking (Durability Cracking) – Cause & Prevention

Durablity Cracking in Concrete Slab

D-Cracking (Durability Cracking) –  Cause & Prevention Summary D-cracking is cracking in concrete pavements caused by freeze-thaw cycles deteriorating the aggregate in concrete.  Water naturally accumulates at the base and sub-base layers under concrete.  When this water suffers from freeze-thaw cycles it wears on the durability of the concrete and begins to crack in the … Read more

Carbonation of Concrete – Various Failure Mechanisms of Concrete

carbonated RCC

Carbonation of Concrete – Various Failure Mechanisms of Concrete What is Carbonation-Process Carbonation is the formation of calcium carbonate (CaCO3) by a chemical reaction in the concrete. The creation of calcium carbonate requires three equally important substances: carbon dioxide (CO2), calcium phases (Ca), and water (H2O). Carbon dioxide (CO2) is present in the surrounding air, … Read more