CORROSION THE PARKING STRUCTURE KILLER
· Are your garages being unnecessarily rebuilt in small sections due to rebar corrosion on advice from the engineering establishment?
· Stop corrosion damage by applying SURTREAT corrosion inhibitor technology and reduce future maintenance cost.
SURTREAT Offers Complete Line of Migratory Corrosion Inhibitors
· Low cost and long lasting
· Proven performance over 25 years of use on reinforced concrete structures
· Reduces corrosion hot spots where most damage occurs
· Easy to apply along with repairs
· Increases strength and reduces porosity of concrete
· Proven to extend structure life and reduce maintenance cost
Rebar corrosion is not uniform as observed by the random pattern of deck surface concrete delamination and spalling.
Extension of time between the need for surface repairs caused by rebar corrosion is related to the control of corrosion hot spots. The SURTREAT powerful anodic type of surface applied migratory corrosion inhibitors are proven to reduce the corrosion rate at these hot spots as well as the overall average corrosion rate.
Testing proves that the application of SURTREAT corrosion inhibitors along with the needed repairs will extend the time to next repair cycle by 15 to 30 years.
The corrosion rate of rebar in a parking structure deck are displayed on the following bar graph in terms of micrometers of rebar steel lost per year before and after application of the Surtreat corrosion inhibitor system composed of TPS XII and TPS II vapor and liquid phase migratory corrosion inhibitors shows how the damage causing corrosion hot spots are reduced down to the average level and will significantly extend the time before any new surface damage occurs.
· Are your garages being unnecessarily rebuilt in small sections due to rebar corrosion on advice from the engineering establishment?
· Stop corrosion damage by applying SURTREAT corrosion inhibitor technology and reduce future maintenance cost.
SURTREAT Offers Complete Line of Migratory Corrosion Inhibitors
· Low cost and long lasting
· Proven performance over 25 years of use on reinforced concrete structures
· Reduces corrosion hot spots where most damage occurs
· Easy to apply along with repairs
· Increases strength and reduces porosity of concrete
· Proven to extend structure life and reduce maintenance cost
Rebar corrosion is not uniform as observed by the random pattern of deck surface concrete delamination and spalling.
Extension of time between the need for surface repairs caused by rebar corrosion is related to the control of corrosion hot spots. The SURTREAT powerful anodic type of surface applied migratory corrosion inhibitors are proven to reduce the corrosion rate at these hot spots as well as the overall average corrosion rate.
Testing proves that the application of SURTREAT corrosion inhibitors along with the needed repairs will extend the time to next repair cycle by 15 to 30 years.
The corrosion rate of rebar in a parking structure deck are displayed on the following bar graph in terms of micrometers of rebar steel lost per year before and after application of the Surtreat corrosion inhibitor system composed of TPS XII and TPS II vapor and liquid phase migratory corrosion inhibitors shows how the damage causing corrosion hot spots are reduced down to the average level and will significantly extend the time before any new surface damage occurs.
PARKING STRUCTURE DECK SURFACE
· Average corrosion rate before application of TPS XII and TPS II = 100 micrometers of steel per year (µM/Yr.)
· Average corrosion rate after application = 28µM/Yr.
· Average rebar corrosion rate reduced by 72 µM/Yr
· Average rate of top 5 corrosion hot spots before application = 250µM/Yr.
· Average rate of top 4 corrosion hot spots after application = 21µM/Yr.
The Need For Future Repairs – Service Life Extension
· Future need for repairs is defined by the appearance of concrete spalls due to rebar corrosion
· Experience shows that the concrete delamination and spalling occurs at 12.5 % of rebar diameter expansion due degree of further rebar corrosion
An equation is written for calculating the time required for future rebar corrosion to cause concrete surface damage as well as structural deficiency.
T = D/2 x 10-3 x R(t) x K
· T = Number of years for future surface damage
· D = Increase in rebar rust expansion from time zero to cause surface damage
· 2 x 10-3 = Correction of rebar radius to diameter and millimeters to micrometers
· R(t) = Rebar corrosion rate at time zero in µM/Yr.
· K = Correction factor multiplying the average corrosion rate to account for damage causing corrosion hot spots
Calculation Data
· Starting rebar diameter = 20mm
· Percent change in rebar diameter to cause damage = 10%
· Change in rebar diameter to cause damage = 2mm
· Average corrosion rate before application of TPS XII and TPS II =100µM/Yr.
· Value of K based on difference of corrosion hot spot rate and the average rate = 2.5
· Average corrosion rate after application of TPS XII and TPS II = 28µM/Yr.
· Value of K factor after application = 1
Before Application of Corrosion Inhibitors
T = 2mm/2 x 10-3 x 100 µM/Yr x 2.5 = 4 years
Time for damage to appear without use of K factor
T = 2mm/2 x10-3 x 100µm/Yr = 10 Years
After Application Of Corrosion Inhibitors
T = 2mm/ 2x10-3 x 28 µM/Yr x1 = 35 Years
Application of corrosion inhibitors along with needed repairs will extend time to next repair cycle by 15 to 30 years.
Conclusion
Structure service life prediction calculation is an effective tool to establish maintenance schedules and budgets.
The use of corrosion inhibitors reduces maintenance and reconstruction costs by extending the time allotted between maintenance, repair and reconstruction cycles.
Robert A. Walde, Chief Technical Officer, Surtreat Holding, LLC contact
· Average corrosion rate before application of TPS XII and TPS II = 100 micrometers of steel per year (µM/Yr.)
· Average corrosion rate after application = 28µM/Yr.
· Average rebar corrosion rate reduced by 72 µM/Yr
· Average rate of top 5 corrosion hot spots before application = 250µM/Yr.
· Average rate of top 4 corrosion hot spots after application = 21µM/Yr.
The Need For Future Repairs – Service Life Extension
· Future need for repairs is defined by the appearance of concrete spalls due to rebar corrosion
· Experience shows that the concrete delamination and spalling occurs at 12.5 % of rebar diameter expansion due degree of further rebar corrosion
An equation is written for calculating the time required for future rebar corrosion to cause concrete surface damage as well as structural deficiency.
T = D/2 x 10-3 x R(t) x K
· T = Number of years for future surface damage
· D = Increase in rebar rust expansion from time zero to cause surface damage
· 2 x 10-3 = Correction of rebar radius to diameter and millimeters to micrometers
· R(t) = Rebar corrosion rate at time zero in µM/Yr.
· K = Correction factor multiplying the average corrosion rate to account for damage causing corrosion hot spots
Calculation Data
· Starting rebar diameter = 20mm
· Percent change in rebar diameter to cause damage = 10%
· Change in rebar diameter to cause damage = 2mm
· Average corrosion rate before application of TPS XII and TPS II =100µM/Yr.
· Value of K based on difference of corrosion hot spot rate and the average rate = 2.5
· Average corrosion rate after application of TPS XII and TPS II = 28µM/Yr.
· Value of K factor after application = 1
Before Application of Corrosion Inhibitors
T = 2mm/2 x 10-3 x 100 µM/Yr x 2.5 = 4 years
Time for damage to appear without use of K factor
T = 2mm/2 x10-3 x 100µm/Yr = 10 Years
After Application Of Corrosion Inhibitors
T = 2mm/ 2x10-3 x 28 µM/Yr x1 = 35 Years
Application of corrosion inhibitors along with needed repairs will extend time to next repair cycle by 15 to 30 years.
Conclusion
Structure service life prediction calculation is an effective tool to establish maintenance schedules and budgets.
The use of corrosion inhibitors reduces maintenance and reconstruction costs by extending the time allotted between maintenance, repair and reconstruction cycles.
Robert A. Walde, Chief Technical Officer, Surtreat Holding, LLC contact
Surtreat Holding, LLC 437 Grant Street, Pittsburgh, PA 15219; 412.281.1202, official website www.surtreat.info
Max Merzlikin, Surtreat Holding, LLC 2015