Protecting your investments since 1979.
Sunday, 24 November 2013 15:16

The Problem of Corrosion

Written by 
Rate this item
(0 votes)

The Problem: Corrosion of Steel in Concrete

More than $5 billion is spent each year to repair and rebuild concrete structures damaged by corrosion of reinforcing steel. This damage is seen every day on bridges, buildings, parking ramps and other steel-reinforced concrete structures.

The Cause: Contamination

When first poured and cured, concrete provides a friendly environment for steel. But it can turn hostile over time as several substances penetrate the concrete. Carbonation occurs when carbon dioxide enters the concrete, reacting with the lime and lowering the pH. In addition, chloride ions from deicing salts or salt-laden air can combine with water and oxygen to create a corrosive environment. An electrochemical corrosion cell is established and the process of delamination begins. As the rebar corrodes, rust forms and takes up more volume than the steel it replaces. This puts expansive forces on the concrete, which ultimately lead to cracking, spalling, and delamination of the concrete.


 Signs of Corrosion

Visible signs of corrosion may first appear as cracks. Then, rust stains may appear at the surface near the corroding rebar. As corrosion advances, the concrete may spall or delaminate, often exposing the corroded rebar. Left untreated, the process continues until the concrete becomes structurally unsound.


Read 15091 times Last modified on Sunday, 24 November 2013 18:05

Leave a comment

Make sure you enter the (*) required information where indicated. HTML code is not allowed.

Protecting Infrastructure Worldwide

Since 1979

Twitter Feeds



Celebrating 35 years of excellence in corrosion control.