1、Designation: D 4788 03Standard Test Method forDetecting Delaminations in Bridge Decks Using InfraredThermography1This standard is issued under the fixed designation D 4788; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year o
2、f last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the determination of delamina-tions in portland-cement concrete bridge decks using infrared
3、thermography. This test method is intended for use on exposedand overlaid concrete bridge decks.1.2 A Precision and Bias statement has not been developedat this time. Therefore, this standard should not be used foracceptance or rejection of a material for purchasing purposes.NOTE 1This test method c
4、an be used on asphalt or concrete overlaysas thick as 4 in. (100 mm).1.3 This test method uses an imaging infrared scanner andvideo recorder, mounted on a vehicle, to detect delaminationsand debonded areas on bridge decks and to record theinformation.1.4 The values stated in inch-pound units are to
5、be regardedas the standard.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations p
6、rior to use.2. Referenced Documents2.1 ASTM Standards:D 4580 Practice for Measuring Delaminations in ConcreteBridge Decks by Sounding23. Summary of Test Method3.1 The vehicle-mounted infrared scanner and video re-corder is driven over the center of each lane of a bridge deck.The data from the scanne
7、r is recorded on video tape. Delami-nations appear as white or “hot areas on a gray or “coolerbackground in the video image on a monochrome scannersystem during daytime testing. During nighttime testing, thedelaminations will appear as dark or “cooler areas on a whiteor “warmer background. Delaminat
8、ions will appear as thewarmer colors on color scanner systems during daytimetesting. Calibration of thermal anomalies using sounding tech-niques are used to determine the colors associated withdelaminations.3.2 The conventional video image is used to edit theinfrared image and separate those patches
9、 or surface defectsthat may be present and may appear as hot areas.3.3 The video recording is used to map the delaminatedareas at a suitable scale.4. Significance and Use4.1 This test method may be used in conjunction with othertest methods in determining the general condition of a bridgedeck.4.2 Ar
10、eas indicated as delaminated on overlaid bridge decksmay be an indication of lack of bond between the overlay andthe underlying bridge deck. This test method may be used indetermining specific areas of delaminations requiring repair.5. Apparatus5.1 GeneralIn order to collect data on the areal extent
11、 andlocation of the delaminations, the following apparatus isrequired:5.1.1 Infrared Scanner An imaging infrared scanner hav-ing a minimum thermal resolution of 0.2 Celsius degrees underambient air conditions. The scanner shall be mounted on thefront of the vehicle at a height sufficient to allow a
12、minimumimage width of 14 ft (4.3 m). The scanner shall be capable ofproducing a television-compatible image.5.1.2 Video Recorders capable of reproducing a thermalimage or a conventional video image. Each device shall have atleast one audio channel available and provide a minimumresolution of 240 lin
13、es per inch. Two are required.5.1.3 Video Camera A conventional video camera capableof viewing a minimum image of 14 ft (4.3 m) and producing acolor video signal that can be recorded on a standard videorecorder.1This test method is under the jurisdiction of ASTM Committee D04 on Roadand Paving Mater
14、ials and is the direct responsibility of Subcommittee D04.32 onBridges and Structures.Current edition approved Feb. 10, 2003. Published May 2003. Originallyapproved in 1988. Last previous edition approved in 2001 as D 4788-88 (2001).2Annual Book of ASTM Standards, Vol 04.03.1Copyright ASTM Internati
15、onal, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5.1.4 Distance Measuring Device having an accuracy of63 in. (76 mm) over the longest span in the deck. The outputof this device shall be recorded by both the infrared videorecorder and the conventional video re
16、corder.5.1.5 Test Vehicle on which the imaging infrared scannerand video recorder will be mounted. The vehicle shall becapable of supporting the infrared scanner and the conventionalvideo camera at a height sufficient to allow a minimum widthof 14 ft (4.3 m) of pavement to be observed at one time. T
17、hevehicle shall be capable of supplying the necessary electricalpower required for the instrumentation.5.1.6 Contact Thermometer having a minimum tempera-ture resolution of Celsius degrees.6. Procedure6.1 Prior to the survey remove any debris that has accumu-lated on the deck.6.2 Dry the bridge deck
18、 for a minimum of 24 h prior to thetest.6.3 Collect data from one end of the bridge deck to the otherin a continuous fashion.6.4 For the delaminations to be identified by an imaginginfrared scanner, there must be a temperature difference, Dt,between the delaminated or debonded area and the adjacents
19、olid concrete of at least 0.5 Celsius degrees. Weather condi-tions must include sunshine. A minimum of 3 h direct sunshineare generally sufficient to create a temperature difference of 0.5Celsius degrees. Establish the magnitude of Dtusing a contactthermometer having a minimum resolution of 0.1 Cels
20、iusdegrees. Confirm thermal anomalies and the existence ofdelamination in the field using coring or sonic techniques asdescribed in Practice D 4580. Confirm coincidental surfacedefects in the field also.6.5 Do not test when the wind velocity exceeds 30 mph (50kph).6.6 Take care when testing or inter
21、preting data, or both,from areas that are or have been shaded by adjacent structures,trees, overhead signs, and the like. Areas adjacent to barriersmay become too hot to provide accurate data due to eitherreflected heat or trapped hot air. It may be necessary to foregoinfrared thermography testing i
22、n such areas.6.7 While data can be collected any time of the year, themagnitude of Dtwill be smaller during the winter months, andmay preclude the testing of bridge decks. Testing shall not becarried out when ambient air temperatures are less than 32F(0C) as ice in delaminations will cause false rea
23、dings. As aguide, an ambient temperature rise of 20 Fahrenheit degreeswith4hofsunandwinds less than 15 mph (24 kmph), willallow accurate data collection on portland-cement concretesurfaces during winter months. On asphalt covered decks, anambient air temperature rise of 20 Fahrenheit degrees with at
24、least6hofsunandwinds less than 15 mph (24 kmph) arenecessary for winter use of this procedure.6.8 Survey the entire bridge deck by making one pass perlane. When shoulder areas are wider than 3 ft (1 m) make aseparate pass along the shoulder.6.9 Collect data at speeds no greater than 10 mph (16 kph).
25、6.10 Should field confirmation of the existence of a delami-nated or debonded area be required, select a core location(s)during the inspection. Mark the location(s) for coring eitherduring the survey or subsequent to the infrared survey.7. Interpretation and Plotting of Results7.1 Plot the delaminat
26、ions on a scaled plan of the bridgedeck using either a manual or a computerized process.7.2 Total the delaminated areas and present as a percentageof the total deck area in square feet (square metres).8. Report8.1 The report shall include the following information:8.1.1 Bridge location and descripti
27、on,8.1.2 Survey methods used and description thereof, includ-ing equipment used and the operators names,8.1.3 Data of test and environmental conditions,8.1.4 Scaled plan of the bridge deck showing the areas ofdelamination and debonding,8.1.5 Area of the bridge deck, ft2(m2) and the percentage ofthe
28、area delaminated or debonded, and8.1.6 Location and condition of any cores taken.9. Precision and Bias9.1 It is not possible to specify the precision of the proce-dure in this test method for measuring delamination of bridgedecks because comparative data is not available. Repeatabilitystudies are av
29、ailable. Since a precision statement for thisstandard has not been developed, this test method is to be usedfor research or informational purposes only. Therefore, thisstandard should not be used for acceptance or rejection of amaterial for purchasing purposes.NOTE 2Available data shows that infrare
30、d thermography can detectbetween 80 and 90 % of the delaminations found in an exposed portland-cement concrete deck and 80 to 90 % of the delaminations in an asphaltoverlaid bridge deck.3,4,5Interoperator testing, using the same infrared scanner, hasshown that operators on the same bridge, on the sa
31、me day, willdetect the same areas of thermal anomaly. Interoperator evalu-ation of the collected data has shown a variation of 65%ofthe known square footage of delamination. Interoperator test-ing was carried out using 4 operators on two bridge decks, oneexposed concrete and one bituminous overlaid
32、structure.10. Keywords10.1 bridge decks; infrared thermography3D. G. Manning, F. B. Holt, “Detecting Delaminations in Concrete BridgeDecks, Concrete International, Nov. 1980, pp. 34.41.4D. G. Manning, F. B. Hold, “Detecting Deterioration in Asphalt CoveredBridge Decks, Transportation Research Record
33、 899, TRB, pp. 1020.5B. W. Love, “The Detection of Delaminations in Reinforced Bridge DecksUsing Infrared Thermography, Indiana Department of Highways, June, 1986.D4788032ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedi
34、n this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and mu
35、st be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of th
36、eresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D4788033
