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Evaluating structures using impulse radar and sonic techniques
N DT A b s t r a c t s 52925 AI Qadi, LL.; Weyers,R.E.; Galagedera, N~L.; Cady, P.D. Condition evaluation o1' concrete bridges relative to reinforcement corrosion. Volume 4. Deck membrane effectiveness and a method for evaluating m e m b r a n e integrity Virginia Polytechnic Inst. and State Univ., Blacksburg, Virginia (United States), PB93-11691 I/GAR, 150pp. (Sep. 1992) An intensive investigation was conducted to evaluate membrane performance and effectiveness. The main objectives of the study were to: develop a nondestructive test method for evaluating the integrity of membranes in place; investigate the effectiveness of membranes, relative to chloride barrier properties, as a function of membrane integrity;, and evaluate the factors that may fffect membrane performance, including membrane type and age, climate, and deicer application rate. A nondestructive methodology nsing ultrasonic pulse velocity was developed to predict the membrane status. The laboratory study and field validation concluded that preformed membrane systems reduce chloride intrusion when properly installed and overlaid with at least 2.5 in. (6.4 cm) of hot-mix asphalt, which should be kept in good service condition. An average life of 40 years is expected for preformed membrane systems, and an increaseof 25 years in bridge deck life is exl[~c~. 52877 South,J.M.; Hahin, C.; Telford, R.O. Analysis, inspection, a n d repair methods for pin connections on Illinois bridges Illinios State DepL of Transportation, Springfield (United States), PB93-136372/GAR, 102pp. (Apr. 1992) The report documents methods used in Illinois for analysis, inspection, and repair of pin connections in bridges. Weldable foil strain gages were used to detect the effects of urflmown levels of fixity in pins on cantilever truss bridges. The maximum effect of complete fixity on pins and hangers were estimated with finite element models of both cantilever truss and cantilever girder bridges. A method for calculating factor of safety for pins based on distortion energy principles is presented. 52815 Hick,H.; Wilier,If.; Winter, E.; Simacek, F. Acoustic emission measurements on bridges Journal of Acoustic Emission, Vol. 10, No. 3-4, pp. 67-70 (1992) A short experimental program was carried out to investigate the suitability of acoustic emission m'~.lysisfor the structural monitoring and checking of bridges. On a presm~sed concrete bridge we could recognize typical sounds, which were interpreted as friction noises generated by loose rehars. Some flat Teflon suppom were found to emit strong ultrasonic signals due to metallic contact after exhaustion of the radial gap. On a concrete box girder bridge a cra¢,kwas investigated and diagnosed as still acoustically active, despite a previous repair attempt by injection. 52709 Ghorbanpoor,A.; Virmani, Y.P.;Fatemi, G.R. Evaluation of concrete bridges by impact-echo Nondestructive Testing of Concrete Elements and Structures, San Antonio, Texas (United State,,;), 13-15 Apr. 1992, pp. 82-93. Edited by F. Ansari and S. Sture. ASCE (1992) This study has examined the application and further development of a non-desm~ctive evaluation technique, the Impact-Echo for determination of location and extent of voids in the ducts of post-tensioned bridge structural members. Theoretical laboratory, and field studies have been performed and it has been demonstrated that it is possible to detect, with high reliability, the location and extent of voids in the post-tensioning ducts of concrete structures. It was found that information corresponding to the location of voids within concrete members may readily be obtained by examining the wave reflection frequency values, from an induced impact at the surface of the member, due to the wave incidents at the free boundaries of these voids. 52708 Olson,L.D. Sonic NDE of structural concrete Nondestructive Testing of Concrete Elements and Structures, San Antonio, Texas (United State,,;), 13-15 Apr. 1992, pp. 70-81. Edited by F. Ansari and S. Sture. ASCE (1992) Case histories are presented Io illustrate applications of nondestructive evaluation (NDE) methods that use stress waves to characterize the conditions of concrete constroction. The case histories discuss the following NDE methods and applications: 1. Impact Echo to evaluate cracking in a 1923 thin-arch concrete dam on the downstream face; 2. impact Echo to investigate honeycomb and void conditions, and to provide quality assurance of repairs to a box girder bridge; and 3. Ultrasonic Pulse Velocity to define the severity of cracking damage in pre-cast bridge segments and
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for quality assurance of epoxy injection repairs. N-DE methods accurately defined the extent and nature of sound and defective concrete conditions. 52132 Forde, M.C.; McCavitt,N. Sonic NDT a n d r a d a r testing of masonry Non-Destructive Testing in Civil Engineering, Liverpool (United Kingdom), 14-16 Apr. 1993. Vol. 2, pp. 489-505. Edited by J.H. Bungey. The British Institute of NDT (1993) The various methods of non-destroctively testing masonry are reviewed. The value of rotary coring and partially destructive investigation techniques are described in relation to the evaluation of masonry. The principles of digital sonic time domain testing, digital sonic frequency domain testing and digital time domain radar testing are explained and described in relation to applications to masonry bridges and retaining wall structures. From the case studies it is shown that the techniques of digital sonic impulse hammer testing and digital impulse radar testing are complementmy in nature and can be used to cost effectively identify the geometries of mssonry bridges in addition to fault detection, location. 52074 Muravin,G.B.; Lezvinskaya, L.M. Diagnostics of reinforced concrete bridges by the acoustic emission (ALE) method Quality Control of Concrete Structures, Ghent (Belgium), 12-14 Jun. 1991. pp. 357-365. Edited by L. Taerwe and H. Lambotte. E & FN Sport (1991) The questions of the reinforced concrete bridges state diagnostics by the acoustic emission method (AE), including the identification of the kinds of damages, improved sound location, the sWaln-slress slate estimation and correspondence to the criteria of fracture were examined. On the bases of the author's researches in the field of the AE physics of isotropic and beterogenic materials the same points, applying at the expensive, responsible objects monitoring are described in the paper. 51827
Forde,M.C.; McCavitt,N.; Batchelor, AJ.
Evaluating structures using impulse r a d a r
a n d sonic techniques Decommissioning and Demolition 1992, Manchester (United Kingdom), 25-26 Mar. 1992. pp. 118-122. Edited by I.L. Whyte, Thomas Telford Ltd. (1992) This paper outlines new and sophisticated impulse digital nondeslructive testing techniques. The techniques used include impulse digital time domain testing, impulse digital frequency domain testing and digital impulse radar testing. The techniques are described in relation to applications to concrete bridges. It is shown that the techniques of impulse sonic and radar testing are complementary in nature and can be used cost effectively to identify the geometries of structures in addition prior to decommissioning. 51820 Otsuka,H.; Hikosaka, H.; Miyatake, H.; Nakamura, S. Estimation of m a x i m u m stress in old railway riveted I-girder bridges using acoustic emission signals Journal of Acoustic Emission, Vol. 10, No. 1-2, pp. S13-S17 (1991-1992) The applicability of acoustic emission tests for the estimation of the maximum stresses in old riveted girder bridges was investigated. A good agreement between experimental and theoretical values was found. 51644 Chinn,D.J.; Dieterman, H.A. Defect imaging using long-distance ultrasonic testing Review of Progress in Quantitative Nondestructive Evaluation, Brunswick, Maine (United States), 28 Jul.-2 Aug. 1991), Vol. l l B , pp. 1901-1908. Edited by D.O. Thompson and D.E. Chimenti. Plenum Press (1992) In large slroctures, such as bridges and offshore structures, many connections and critical nodes are not easily accessible to within the range required for present ultrasonic testing techniques. Reasons for the lack of accessibility include the physical limitations of the probe and the inspector as well as environmental and scheduling constraints. To increase the inspection area and facilitate accessibility at hard- to-reach connections, long-distance ultrasonic testing (LDUT) has been under investigation. In this method, ultrasonic testing is performed at distances of 0.5 to 1.0 meter from the detection area. An angled probe generates a wave field that reaches the detection area after several reflections from the plate faces. Wavelengths are kept sufficiently small in relation to the plate thickness so that no plate waves are generated, only bulk waves are used in detection.
391
for quality assurance of epoxy injection repairs. N-DE methods accurately defined the extent and nature of sound and defective concrete conditions. 52132 Forde, M.C.; McCavitt,N. Sonic NDT a n d r a d a r testing of masonry Non-Destructive Testing in Civil Engineering, Liverpool (United Kingdom), 14-16 Apr. 1993. Vol. 2, pp. 489-505. Edited by J.H. Bungey. The British Institute of NDT (1993) The various methods of non-destroctively testing masonry are reviewed. The value of rotary coring and partially destructive investigation techniques are described in relation to the evaluation of masonry. The principles of digital sonic time domain testing, digital sonic frequency domain testing and digital time domain radar testing are explained and described in relation to applications to masonry bridges and retaining wall structures. From the case studies it is shown that the techniques of digital sonic impulse hammer testing and digital impulse radar testing are complementmy in nature and can be used to cost effectively identify the geometries of mssonry bridges in addition to fault detection, location. 52074 Muravin,G.B.; Lezvinskaya, L.M. Diagnostics of reinforced concrete bridges by the acoustic emission (ALE) method Quality Control of Concrete Structures, Ghent (Belgium), 12-14 Jun. 1991. pp. 357-365. Edited by L. Taerwe and H. Lambotte. E & FN Sport (1991) The questions of the reinforced concrete bridges state diagnostics by the acoustic emission method (AE), including the identification of the kinds of damages, improved sound location, the sWaln-slress slate estimation and correspondence to the criteria of fracture were examined. On the bases of the author's researches in the field of the AE physics of isotropic and beterogenic materials the same points, applying at the expensive, responsible objects monitoring are described in the paper. 51827
Forde,M.C.; McCavitt,N.; Batchelor, AJ.
Evaluating structures using impulse r a d a r
a n d sonic techniques Decommissioning and Demolition 1992, Manchester (United Kingdom), 25-26 Mar. 1992. pp. 118-122. Edited by I.L. Whyte, Thomas Telford Ltd. (1992) This paper outlines new and sophisticated impulse digital nondeslructive testing techniques. The techniques used include impulse digital time domain testing, impulse digital frequency domain testing and digital impulse radar testing. The techniques are described in relation to applications to concrete bridges. It is shown that the techniques of impulse sonic and radar testing are complementary in nature and can be used cost effectively to identify the geometries of structures in addition prior to decommissioning. 51820 Otsuka,H.; Hikosaka, H.; Miyatake, H.; Nakamura, S. Estimation of m a x i m u m stress in old railway riveted I-girder bridges using acoustic emission signals Journal of Acoustic Emission, Vol. 10, No. 1-2, pp. S13-S17 (1991-1992) The applicability of acoustic emission tests for the estimation of the maximum stresses in old riveted girder bridges was investigated. A good agreement between experimental and theoretical values was found. 51644 Chinn,D.J.; Dieterman, H.A. Defect imaging using long-distance ultrasonic testing Review of Progress in Quantitative Nondestructive Evaluation, Brunswick, Maine (United States), 28 Jul.-2 Aug. 1991), Vol. l l B , pp. 1901-1908. Edited by D.O. Thompson and D.E. Chimenti. Plenum Press (1992) In large slroctures, such as bridges and offshore structures, many connections and critical nodes are not easily accessible to within the range required for present ultrasonic testing techniques. Reasons for the lack of accessibility include the physical limitations of the probe and the inspector as well as environmental and scheduling constraints. To increase the inspection area and facilitate accessibility at hard- to-reach connections, long-distance ultrasonic testing (LDUT) has been under investigation. In this method, ultrasonic testing is performed at distances of 0.5 to 1.0 meter from the detection area. An angled probe generates a wave field that reaches the detection area after several reflections from the plate faces. Wavelengths are kept sufficiently small in relation to the plate thickness so that no plate waves are generated, only bulk waves are used in detection.