Greenkill Ave. Bridge Report, Kingston, NY

8/11/2019 Greenkill Ave. Bridge Report, Kingston, NY

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CHICAGO HOUSTON MIAMI61 Garlisch Drive 1036 1st St E, Ste A3 1850 S. Ocean Drive, Ste 3804Elk Grove Village, IL 60007 Humble, TX 77338 Hallandale, FL 33009P847.459.9090 P 281.446.7363 P 954.676.4147

www.uctgroup.com www.radarviewllc.com

August 20, 2014 UCT Project No.: 14181

Ms. Emily Rodriguez [email protected]

Advance Testing Co.3348 Route 208Campbell Hall, NY 10916

Re: Laboratory Studies of Concrete Core SamplesGreenkill Avenue BridgeUlster County, Kingston, New YorkProject No.: 140473

Dear Ms. Rodriguez:

Universal Construction Testing, Ltd. (UCT) has completed laboratory studies of two (2)concrete core samples from the referenced project, which were delivered to ourlaboratories on August 8, 2014.

Reportedly, the bridge was constructed circa 1950’s.

Petrographic examination was requested on both core samples to evaluate the concreteproperties and to determine the general quality and condition of the concrete.

Refer to Table 1 below for individual core sample identification, location and the type ofexamination that was performed.

Table 1. Core Sample Identification, Location

Core ID Lab No. Location Petrographic Examination

(ASTM C856)

3 14-0694A North Abutment X

4 14-0694B South Abutment X

SUMMARY OF FINDINGS

Based on petrographic findings, two modes of internal distress have lead to thecurrent condition of the concrete. Both of the modes below are expansive inthe presence of moisture:

1. Freeze-thaw damage2. Alkali-silica reactivity





Ms. Emily Rodriguez UCT Project No.: 14181 August 20, 2014 Page 3 of 11

Petrographic Examination

Petrographic examination was conducted in general accordance with ASTM C856,Standard Practice for Petrographic Examination of Hardened Concrete.

Individual results of the petrographic examination are summarized below.

Core Sample 3 (14-0694A)

General

The core is 3-in. (76 mm) diameter and approximately 10.5-in. (267 mm)long; partial abutment thickness. The exterior surface of the core is flat andrough, exhibiting exposed sand grains; the general quality of this surface isgood. The interior of the core is a fractured surface which passes through andaround aggregate particles. The consolidation of the concrete is good with no

signs of segregation.

Figure 1 – Core Sample 3 as-received for examination. Note the generalappearance and condition of the concrete; exterior surface left.

ReinforcementWelded-wire fabric, 0.2-in. (5 mm) diameter, is exposed on the fracturedinterior surface with approximately 10-in. (254 mm) of concrete cover. A loosepiece of 0.2-in. (5 mm) diameter welded-wire fabric was received separatedfrom the core; based on impressions in the concrete, this wire fabric hasapproximately 3-in. (76 mm) of concrete from the cores exterior surface. Thesteel wires exhibit surficial corrosion and pitting.

Welded-Wire FabricImpression Clean




Cracks

An open crack is observed at the level of the reinforcement which is locatedapproximately 3-in. (76 mm) from, and oriented almost parallel to, the exteriorsurface; the crack passes through and around aggregate particles. At leastone hairline crack traverses the surface. Other tighter microcracks in the corehave more of a random orientation.

Unit Weight

The unit weight of the concrete sample (SSD), as received, is 147 pcf.

Air Content

The air content is estimated at 1-2%. The concrete is non-air-entrained.

Figure 2 – Photomicrograph showing the non-air-entrained paste in CoreSample 3 (millimeter scale). Radial microcracking initiates within the coarseaggregate and the microcracks contains ASR gel expand extending out into thesurrounding mortar (arrows).

Secondary DepositsWhite deposits (ASR gel) occur on the surfaces of the open cracks and inmicrocracks radiating from reacting aggregate particles.

Inwardly projecting ettringite crystals are observed lining numerous air voids.Secondary ettringite is not unusual in portland cement concrete.

Carbonation

Paste carbonation extends inward of 0.4-in. (10 mm) from the exteriorsurface.




Depth of carbonation; phenolphthalein method:o high alkalinity (pH), noncarbonated paste turns magentao low alkalinity (pH), carbonated paste remains unaffected

Water-Cement Ratio

The water-cement ratio is considered to have been moderate.

Figure 3 – Thin-section photomicrograph showing the cement-pastemicrostructure in Core Sample 3. 100X, plane light. A microcrack containingASR gel extends from a coarse aggregate particle into the hardened paste (redarrows).

Paste Properties

Color Medium-light gray

Hardness Moderately hard

Luster Dull to subvitreous

Paste Volume Normal paste content

Morphology of Calcium Hydroxide Medium-size crystals

Mineralogy of the Cement Portland cement (C-S-H)

Hydration Normal but advanced

Residual Portland Cement Grains 1% to 3% clinker particles

Supplementary Cementitious Materials None observed

Paste

Aggregate




Paste-Aggregate Bond

The paste-aggregate bond is moderately tight; freshly fractured surfaces ofconcrete pass through and around aggregate particles.

Aggregate

The gradation of the coarse aggregate appears uneven; particle distribution isslightly non-uniform. The coarse aggregate exhibits evidence of deleteriousreactions with the paste. Cracks containing ASR gel pass through, or radiatefrom, some coarse aggregate particles. Fine aggregate grading anddistribution is fairly good.

Figure 4 – Cut and lapped cross section of the exterior 5-in. (127 mm) of CoreSample 3. Exterior surface left. Red arrows indicate a few randomly-orientedmicrocracks (enhanced by moisture dry-back). ASR gel is observed on thesurfaces of the open crack; a clear indication the crack is not fresh.

The coarse aggregate is 1- to 1.5-in. (25-38 mm) top size crushed dolomiticlimestone (with siliceous impurities). Individual particles are angular to sub-rounded and bladed to elongate.

The fine aggregate is natural sand composed mainly of quartz and smallamounts of various other rocks and minerals. Individual sand grains areangular to well rounded and elongate to spherical.

ASR De osits




Core Sample 4 (14-0694B)

General

The core is 3-in. (76 mm) diameter and approximately 14-in. (356 mm) long;

partial abutment thickness. The exterior surface of the core is flat and roughexhibiting exposed sand grains; the general quality of the top surface is good.The interior of the core is a fractured surface which passes through andaround aggregate particles. The consolidation of the concrete is good with noevidence of segregation.

Figure 5 – Core Sample 4 as-received for examination. Note the generalappearance and condition of the concrete; exterior surface left. Core sample isextensively cracked in the midsection (arrows), particularly from a depth of 3-in. (76 mm) to a depth of 7-in. (178 mm).

ReinforcementNo actual steel reinforcement is observed. A single impression from whatappears to have been a 0.2-in. (5 mm) diameter wire is presentapproximately 3-in. (76 mm) from the exterior surface; impression is clean.

Cracks

Open cracks are observed at depths of approximately 3-in. (76 mm), 4.5-in.(114 mm) and 7-in. (178 mm) from the exterior surface; exterior surface is tothe left in Figure 5. These cracks are oriented roughly parallel to the exteriorsurface and pass through and around aggregate particles. Sub-parallelcracks and microcracks are observed throughout the core; some extendinginward from the exposed surface.

Heavily Cracked Area




Unit Weight

The unit weight of the concrete sample (SSD), as received, is 146 pcf.

Air Content

The air content is estimated at 2-3%. The concrete is considered non-air-entrained.

Figure 6 – Photomicrograph showing sub-surface cracking in Core Sample 4(millimeter scale). These cracks are observed approximately 3.5-in. (89 mm)from the exposed surface and pass through and around aggregate particles.The observed crack pattern is consistent with freeze-thaw damage.

Secondary Deposits

White deposits of ASR gel are observed in microcracks of reacting

aggregates and some air voids.

Inwardly projecting ettringite crystals are observed many air voids.

Carbonation

The paste is carbonated to a depth inward of 0.15-in. (3.8 mm) from theexterior surface.




Water-Cement Ratio

The water-cement ratio is considered to have been moderate.

Figure 7 – Thin-section photomicrograph showing the cement-paste

microstructure in Core Sample 4. Note secondary ettringite partially lining void.100X, plane light.

Paste Properties

Color Medium-light gray

Hardness Moderately hard

Luster Dull to subvitreous

Paste Volume Normal paste content

Morphology of Calcium Hydroxide Medium-size crystals

Mineralogy of the Cement Portland cement (C-S-H)Hydration Normal but advanced

Residual Portland Cement Grains 1% to 3% clinker particles

Supplementary Cementitious Materials None observed

Ettringite




Paste-Aggregate Bond

The paste-aggregate bond is moderately tight; freshly fractured surfaces ofconcrete pass through and around aggregate particles.

Aggregate

The gradation of the coarse aggregate appears uneven; particle distribution isslightly non-uniform. Fine aggregate grading is good. The aggregate, mainlycoarse, exhibits evidence of deleterious reactions with the paste.

Figure 8 – Cut and lapped cross section of Core Sample 4 showing cracking inthe exterior 6-in. (152 mm) of concrete. The cracks are enhanced from moisturedry-back. Many cracks are oriented parallel to the exposed surface (arrows).Exterior surface left.

The coarse aggregate is 1- to 1.5-in. (25-38 mm) top size crushed dolomiticlimestone (with siliceous impurities). Individual particles are angular to sub-

rounded and bladed to elongate.

The fine aggregate is natural sand composed mainly of quartz and smallamounts of various other rocks and minerals. Individual sand grains areangular to well rounded and elongate to spherical.

*******




We appreciate the opportunity to be of service to you. Should you have any questions,please do not hesitate to contact us.

Sincerely yours,Universal Construction Testing, Ltd.

David B. VollmerSenior Consultant - Petrographic Services

Mark E. Hughes, P.E.General Manager

mh-dv / Report 14181

Samples will be discarded after ninety (90) days unless other disposition is requested by you.

Greenkill Ave. Bridge Report, Kingston, NY

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