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KTA.TATOR, lNG.115 Technology Drive, Pittsburgh, PA 15275

February 8,2002

Mr. Jonathan TurnerTurnaSure LLC340 E. Maple Avenue, Suite 305Langhorne, PA 19047

SUBJECT: KTA-Tator,Inc. Test Report for Accelerated Aging ofWeathering Steel Joint - TurnaSure Project No. 210756

Dear Mr. Turner:

In accordance with KTA-Tator, Inc. Proposal PN011969 and TurnaSure LLC Purchase Order No.PO384, KTA-Tator, Inc. (KTA) has completed 500 hours of accelerated aging testing of the weatheringsteel joint. This report contains a description of the accelerated test conditions and the results of theevaluation of the weathering steel joint after 500 hours of testing.

TEST SPECIMEN

The test specimen consisted of a weathering steel joint assembled from 2 steel plates measuring6" x 8 ll2" x 5/8" thick, sandwichedbetween 2 additional steel plates measuring 6" x17" xIl2" thick.The steel plates were fastened together with 12 7/8" diameter x 3" long ASTM A325 Type 3 structuralbolts, each mated with a matching heavy hex nut and hardened washer. Each bolt assembly included 1ASTM F959 DTI washer produced from Type 3 weathering steel. (See Photo 1)

Coatings & Corrosion Consulting r Construction Inspection I Laboratory AnalysisMaterials Testing I Environmental, Health & Safety

Mr. Jonathan Turner February 8,2002

(Photo I - Example of Fastener Set Used for Test)

The weathering steel joint test specimen was designed and constructed in accordance withTurnaSure LLC instructions by High Steel Structures, Inc. of Lancaster, PA and assembled at LaboratoryTesting, Inc. (LTI) of Hatfield, PA. The test joint design was intended to simulate a typical joint of a steelhighway bridge. (See Photos 2 through 5, provided courtesy of LTI.)

@hoto 2 - Cross-section of joint before Tightening)

Mr. Jonathan Tumer February 8,2002

@hoto 3 - Joint Assembly using Torque Multiplier)

(Photo 4 - Tightened joint dfeeler-gages in residual DTI gaps)

Mr. Jonathan Turner February 8,2002

TESTING PROTOCOL

The objective of the accelerated aging testing was to determine the corrosion protection of thejoint in typical atnospheric exposures. To that end, the weathering steel joint was subjected to 500 hoursof cyclic testing in the Q-Fog test cabinet according to ASTM G85, *Modified Salt Spray (Fog) Testing",AnnexA5, *Dilute Elecfolyte Cyclic Fog/Dry Tesf'.

The testing consisted of exposing the specimen to continuous cycling of I hour fog at ambienttemperature,z4 ! 3" c (75 + 6' F) followed by I hour d.y-off at 35 + 1.5'c (95 + 3' F). The fog wasprovided by an electrolyte solution composed of 0.05% sodium chloride and, 0.35%o ammonium sulfate.The pH of the fog condensate ranged between 5.1 and 5.4 throughout he duration of the testing.

The specimen was oriented in the test cabinet in the horizontal position, with one of the faces ofthe specimen always skyward in order to enable comparisons between exposure of both a 'top flange' aswell as a 'bottom flange' to 'weathering'. The test was concluded after 500 hours of exposure and theweathering steel joint test specimen was removed and disassembled for evaluation.

TEST RESTILTS

The weathering steel joint was carefully disassembled on bctober l7,2OOl at KTA headquartersin Pittsburgh, in the presence of Mr. Jonathan Turner and Mr. David Sharp. The condition of thespecimen, prior to disassembly, was photographically documented. Photographs were also taken todocument the condition of the steel plates, bolts, washers, and load indicator washers drning the entiredisassembly process.

The exterior surface of the joint that was oriented skyward during testing was severely rusted andcovered with rust scale. It was rated as Rust Grade 0-G, (>50 o/o rusted), according to SSPC-VIS 2,"Standard Method of Evaluating Degree of Rusting on Painted Steel Surfaces". Severe rust and rust scale,also rated 0-Go was present along the sides of the joint. (See Photos 6 & 7)

@hoto 5 - Tightened Jointdfeeler gauges in residual Steet gaps)

Mr. Jonathan Turner February 8,2002

@hoto 6 - exterior sur{ace rust) (Photo 7 - side surface rust)

The exposed portions of the bolts, bolt threads, and nuts were fairly clean of rust. When the nutswere removed from the top of the joint it was noted that there was no rust between the nuts and the loadindicator washers. (See Photo 8.) There was also minimal rusting, Rust Grade 4-G (10% rusted),between the bolt heads and the load indicator washers. No rust was present on the bolt shanks where theIoad indicator washers were adjacent to the bolt heads. (See Photo 9.)

@hoto 8 - Lack of corrosion on DTI where it was against hex nut)

@hoto 9 - Lack of corrosion on bolt shank or between load indicator bumps)

Mr. Jonathan Turner February 8,2002

It was noted that any rust that was present on the load indicator washers was at the periphery ofthe washers. An intentional gap of up to 0.005" is normally present during installation between the loadindicator washer and the bolt head or the between the steel plate and the load indicator washer. The gapwas not existent at the periphery of the load indicator washers, but was filled with a patina of rustmeasuring 0.005 inches in thickness. However, the gap remained at the interior portion of the loadindicator inside the patina build-up. The area of the washer adjacent to the steel plate and/or bolt was freeof any rust.

Similarly, corrosion between the plates where gaps had been present appeared to become sealedoff from further corrosion upon build-up of the patina. (See Photo 10.)

@hoto 10 - Patina build-up inhibited further ingress of corrosion.)

Nuts removed from the top (skyrvard) side of the joint revealed clean load indicator washers freeof rust on the inner portion of the washers as well as on the surface of the nuts that were adjacent to theload indicator washers. One of the bolts, when removed from the joint, was so severely rusted at the bolthead, that the top of the bolt exfoliated. The numerals designating the bolt head were still legible in theexfoliated portion of rust scale. (See Photo 11.)

Mr. Jonathan Turner February 8,2002

@hoto 11 - Edoliated portion of an A325 Bolt Head)

Apparently, the load indicator washers oflered protection against rusting to the bolts themselves.It was observed that many of the bolts that were fastened using the load indicator washers were free ofrust on the bolt shafts. In fact, it was seen that the original oil used to protect the bolt in the field was stillpresent on the threads at time of disassembly.

The internal steel plates of the joint were approximately 50% rusted, Rust Grade l-G. The rustwas also surrounding several of the bolt holes, on both the sides with and without load indicating washers.No rust was observed at the junction of several of the bolt heads with the plate due to the protectionof[ered by the load indicator washers. Rust was very minimal, Rust Grade 9-G (0.03% rusted), at the boltholes on which the load indicating washers had been present. No rust was present within 1/8" of the boltholes at these locations, likely due to the high clamping forces in this region. (See Photo 12.)

(Photo 12 - Lack of corrosion in regions of high clamping force.)

Mr. Jonattran Turner February 8,2002

CONCLUSIONS

It became apparent, during disassembly of the joint, that the load indicator washers preventedrusting from occurring on those areas of the plate, bolt, and nut that were fastened with the load indicatorwashers. It was theorized that a barrier of corrosion material stopped the ingress of moisture into the0.005-inch gap present at the load indicator washer, thereby contributing to areas that were fiee ofcorrosion and rust.

If you have any questions concerning the information contained in this report, please call me at412/788-1300, ext. 181.

Very truly yours,

KTA-TATO& INC.

Frank A. MozelewskiSenior Chemist

FAM/BRAjas

cc: William B. CorbettBernard R. ApplemanCynthia L. FairfullScott Rice

JN: 210756(JAS02049

NOTICE: This report represents the opinion of KTA-TATOR, INC. This report is issued in conformance with generalty acceptable industrypractices. While customary precautions were taken to insure that the information gathered and presented is accurate, oomplete, and technioallyconect, it is based on the informatiorl dan4 time, materials, and/or samples afforded