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REPORT September
2007 (after 6 years - 3
months of service) Evaluation of the Termarust (High Ratio Co-Polymerized)
Calcium Sulfonate Coating System on the Bearings and Anchor Bolts on the
For Department of Engineering Services Coating Materials From Termarust Technologies, Project Date: June 2001 REPORT September 19, 2007
Evaluation of the Termarust (High Ratio Co-Polymerized) Calcium
Sulfonate Coating System on the Bearings and Anchor Bolts on the in By: Craig A. Ballinger, P.E. Termarust Technologies Phone: (703) 938-1057 Email: cballinger@termarust.com CURRENT STATUS After 6 years and 3
months of service On September 19, 2007, the
Arlington County Bridge Program Manager and I visited the bridge and inspected
the condition of the bearings and the anchor bolts on the 1.
The condition of the Termarust coating system is
excellent there are no coating failures on any of the bearings or anchor
bolts. 2.
On some bearings there is a small amount of rust
staining on the top of the lower base plate that has leaked down and onto
the top of the base plate. The rust
staining is from very light rust on the underside of the upper base plate,
above the rocker. Apparently these
underside surfaces were not painted adequately. During this inspection some of this rust
staining on the surface was actually wiped off.
(See photos 15, 16 and 21) 3.
On some of the bearings, there is also light rust on
the inner vertical surfaces of the slotted holes in the lower base plate but
not on this section of the anchor bolts.
Although the anchor bolts could be cleaned and painted it was very
difficult (if not impossible) to clean and paint the inner surfaces of these
slotted holes. (See photo 14) 4.
There is some rust staining coming out from under the
underside of the lower base plates. This
is an inaccessible area that could not be adequately cleaned before
painting. During the painting process
Termarust TR2200 Penetrant was applied around the bottom of the base plates,
with the intent that it might penetrate under the base plates and stop any
corrosion. 5.
The color of the Termarust coating system is
essentially the same as when it was applied; i.e. the coating has not faded, or
chalked. OVERVIEW This report covers a trial
project for evaluation of the single coat Termarust high ratio calcium
sulfonate coating system on the bearings and very badly corroded anchor bolts
on two (parallel) bridges in As may be seen from the
following pictures initially there was severe corrosion and considerable loss
of cross sectional area of many of the anchor bolts due to leakage of water
(and salt water) through the deck joints. One of the main differences between the Termarust high
ratio co-polymerized calcium sulfonate coating system and other (more
traditional) coating systems is it chemically stops active corrosion;
including in inaccessible locations; e.g. between pieces of the steel bearing
assemblies. The cleaning/preparation method used for this project was
sandblasting because the work was done under an existing contract that
required sandblasting. Here it is important to
note that the usual method for cleaning and preparing a structure for
application of the Termarust system is with a 5,000 psi pressure washer with
a zero-degree rotating tip and Chlor*Rid in the water for removal of soluble
salts; e.g. chlorides an excessive amount of which will cause failure of
any/all coating systems. [See www.chlor-rid.com
for more information on this topic.] REFERENCE Contact Person
Ravinder K. Singh, P.E., Bridge Program Manager Cell
Phone: 571-220-1882 Construction Management Section OBJECTIVES To evaluate the ability of the Termarust high ratio
calcium sulfonate coating system to chemically stop corrosion on the bearings
and anchor bolts. CLEANING AND APPLICATION PROCEDURES 1.
The
bearings and anchor bolts under the ends of the beams of these twin bridges
were sandblasted. 2.
Termarust
TR2200 Penetrant was applied (with a hand squirt bottle) to all open
connections, the faying surfaces of the bearings and around the bottom edges of
the bottom base plates. 3.
TR2100
Topcoat was immediately applied (wet-on-wet), by hand/brush, as follows: The final result was: ·
10
mils DFT on bare steel and tight rust, and ·
20
mils DFT over the edges of connections, and the anchor bolts and nuts. PICTORIAL OVERVIEW The following pictures provide a pictorial overview
of the project.
Photo 1 Bridges and the general location.
Photo 2 Underside of one of the bridges.
Photo 3 Existing condition of bearings in July
2001. (It is not known what the white deposit on the
surface of the steel is)
Photo 4 Existing condition of anchor bolt, note
corrosion.
Photo 5 Existing condition of anchor bolts severe
corrosion Corrosion ring/shell has expanded and cracked
vertically but it has not yet fallen off (as seen in the next
photo)
Photo 6 Corrosion ring/shell around anchor bolt has
fallen off revealing substantial loss of cross sectional area of the bolt. (Compare
with Photos 11, 14 and 21)
Photo 7 August 2001 after sandblasting and
painting with Termarust.
Photo 8 Close-up of painted bearing and anchor
bolt, August 2001.
Photo 9 Condition, November 2003 no corrosion, after 27 months.
Photo 10 Condition in November 2003, no corrosion
after 27 months.
Photo 11 Condition in November 2003, after 27
months (Compare with Photos 6, 14 and 21).
Photo 12 Condition in November 2003, no corrosion
after 27 months.
Photo 13 Condition in May 2005, no corrosion of the
bearings or anchor bolts.
Photo 14 Condition in May 2005, no corrosion of the
bearings or anchor bolts. (Compare with Photos 6, 11 and 21)
Photo 15 Condition in May 2005, no corrosion of the
bearings or anchor bolts. (Rust staining is from inside of hole in upper
bearing plate)
Photo 16 Condition in May 2005, no corrosion of the
bearings or anchor bolts. (Rust staining is from the underside of the top
bearing plate and inside of holes in plates)
Photo 17 Condition of an exterior bearing in
September 2007, after 6 years (No corrosion or rust staining)
Photo 18 Condition in September 2007 after 6
years (Rust staining is from the underside of the top bearing plate, inside of
holes in plates and under base plate)
Photo 19 Condition in September 2007 after 6
years (Note that rust staining on top of the front corner of the base plate has
been washed off paint under it is in excellent condition)
Photo 20 Condition in September 2007 after 6
years (Rust staining is from the underside of the top bearing plate and inside
of the holes and rusting of the unpainted A-588 steel beam)
Photo 21 Condition in September 2007 after 6
years (Rust staining is from under underside of plates and inside of holes and
the A-588 beam (Compare to Photos
6, 11 and 14)
Photo 22 Condition in September 2007 after 6
years (Rust staining is from unpainted A-588 steel beam) |
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