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Method for monitoring the goodness of the cement bond to a borehole casing
T abstracts. NDT Abstracts is a current awareness service compiled by the National N D T Centre, Harwell Laboratory, Didcot, Oxon, OXll 0RA, UK. The entries are drawn from over 500 British and International publications. Each issue concentrates on one or two subject areas, and contains abstracts entered from 1987 to the present. The sttbjects covered in previous issues are: Acoustic emission (cracks and defects) - April 1989; Acoustic microscopy - February 1990; Eddy current techniques June 1989; Magnetic testing techniques - February 1989; Neutron radiography - August 1989; Real-time radiography - April 1989; Residual stress measurement - D e c e m b e r 1989; Ultrasonic characterization of metals - October 1989
Concrete 42140
Leaird, J.D.; Taylor, M.A.
Acoustic emission investigation into some concrete construction problems Journal of Acoustic Emission, Vol. 8, Nos. 1-2, pp. 5322-5325 (Jan. Jun. 1989) Special Supplement - Extended Summaries of Papers to be presented at the World Meeting on Acoustic Emission, Charlotte, North Carolina, USA, 20-23 Mar. 1989 The construction industry would benefit greatly from a cost effective method of increasing the crack resistance of structural concrete and for the early detection of reactive aggregates. One method proposed to achieve the first objective is to add polypropylene fibers to the concrete. A series of beams were manufactured with polypropylene fibers added and a series without the fibers. These beams were tested in four point loading and the acoustic emission activity from each beam was measured during the load test. The plain concrete beams had 2 to 3 times the acoustic emission activity of the fiber reinforced beams. The results of tests to detect the presence of reactive aggregates are also reported. 41956
Ohtsu, M.; Sakimoto, T.; Kawai, Y.; Yuji, S.
Evaluation of concrete structure deterioration via AE observation of core tests Journal of Acoustic Emission, Voi. 7, No. 4, pp. 167-172 (Oct-Dec. 1988) An AE technique is proposed to evaluate the deterioration of concrete structures by means of tests of core-drilled samples. AE activity during a uniaxial compressive test is quantitatively analyzed based on the rate process theory. In the case of deteriorated concrete, AE events occur actively due to existing critical mierocracks even at low stress level of uniaxial loading. In contrast, AE activity in well- conditioned concrete is only observed just prior to final failure. The discrepancy of these AE activities is reasonably represented by the value of "a" in the rate process theory. To gauge the applicability of the procedure and correlate the deterioration of concrete and the value of "a", fatigue experiments of reinforced concrete slabs were performed and core samples were extracted. The proposed technique is tested by core samples with controlled damage. Results show great promise. 41953
Henkel, D.P.; Wood, J.D.
Acoustic emission testing of flexed concrete beams reinforced with bonded surface plates Journal of Acoustic Emission, Vol. 8, Nos. 1-2, pp. 5318-5321 (Jan. Jun. 1989). Special Supplement - Extended Summaries of Papers to be presented at the World Meeting on Acoustic Emission, Charlotte, North Carolina, USA, 20-23 Mar. 1989 A preliminary study is presented of the acoustic emission (AE) response of stressed concrete beams used in structural engineering subject to fracturing under four point bending. The four concrete members in the study had epoxy bonded thin plates of steel, fibre#ass, carbon and aramid fibre composites. AE activity was correlated to changes in effective beam modulus, in an attempt to identify AE fracture sources in the beam, and characterize AE signal changes induced by the different plate materials. AE is shown to be a useful method of modelling concrete damage. 41895
Ohtsu, M.
Source inversion of acoustic emission for the determination of crack kinematics and kinetics Journal of Acoustic Emission, Voi. 8, Nos. 1-2, pp. 5162-5165 (Jan. Jun. 1989). Special Supplement - Extended Summaries of papers to be presented at the World Meeting on Acoustic Emission, Charlotte, North Carolina, USA, 20-23 Mar. 1989 In the present paper, the determination of crack kinematics and kinetics is reported, as a source inversion procedure of AE. The proposed procedure is applied to AE waveforms in pull-out tests of anchor-holt from concrete block. 41866
Vogel, C.B.; Davis, M.; Guy, J.O.
Method for monitoring the goodness of the cement bond to a borehole casing
110
U.S. Patent No. 4,809,237 (28 Feb. 1989) The quality of cement bonds in borehole casings can be tested using this new method. A logging tool incorporating an acoustic transmitter and receiver is lowered into the borehole. Acoustic radiation from the transmitter is used to insonify the casing and the receiver detects the converted-compressional waves from the casing. 41763
Kwasi, B.-T.
Evaluation of layer moduli in flexible pavement systems using nondestructive and penetration testing methods Dissertation Abstracts International, Vol. 49, No. 8, p. 3337 (Feb. 1989) A research study was conducted to develop procedures for the evaluation of layer moduli in flexible pavement systems using in situ non- destructive (NDT) and penetration tests. The Bitumen Structure Analysis in Roads (BISAR) elastic layer computer program was used to simulate Dynaflect and Falling Weight Deflectometer (FWD) load- deflection response for typical flexible pavements in the state of Florida. A field testing program consisting of Dynaflect, FWD, cone penetration, Marchetti Dilatometer, and plate bearing tests was conducted on fifteen pavement sections in the state of Florida. Cores of the asphalt concrete pavement were collected for laboratory low- temperature theology tests. This provided a reliable and effective method of predicting the asphalt concrete modulus. 41758
Bungey, J.H.
The testing of concrete in structures Surrey University Press, 228pp. (1989) In this second edition of the book, the author speculates upon possible reasons for the deterioration of the ever growing number of concrete structures. Advances made over the last decade, are outlined for the techniques, equipment and methods of inspection of concrete structures. The book emphasises the need for suitably planned testing by plant engineers and provides an overview of testing concrete structures for non-specialist engineers. The procedures, scope and limitations of available test methods are outlined. 41730
Amoco Corporation
Method and apparatus for determining cement conditions U.S. Patent No. 4,802,145 (31 Jan. 1989) Thickness of the cement around wellbore casings can be determined with this device. Acoustic transducers are set at predetermined distances from each other in contact with the interior surface of the casing. The time that an acoustic pulse takes to travel from one transducer to its neighbour provides a measure of cement thickness. 41728
Western Atlas International, Inc.
System for acoustically determining the quality of the cement bond in a cased borehole U.S. Patent No. 4,805,156 (t4 Feb. 1989) This acoustic logging tool can be used to determine the quality of the bond between a borehole wall and its cement casing. A sonde with extendable pads for contact with the surrounding casing is lowered into the borehole. Transducers, arrayed in fours consisting of two transmitters of ultrasonic pulses and two receivers, are disposed on the outer surfaces of the pads. Compensated attenuation between pairs of transmitter and receiver transducers is used to determine the cement bond quality between adjacent transducers. 41646
Stockman, A; Mathieu, P.; Nicholson, P.S.
Ultrasonic characterization of model defects in ceramics (Part 3): spherical inclusions in opaque crystallized glass - theory and practice Materials Evaluation, Vol. 47, No. 3, pp. 358-362 (Mar. 1989) The model for scattering of 25 MHz pulsed focused ultrasound from spherical inclusions in the size range of 50-200 micrometres is compared with actual results for oxide inclusions in crystallized glass. Spherical oxide inclusions are examined in transparent, opaque, crystallized, and partially opaque glass. Signal analysis of the sound waves from inhomogeneities of known size and
NDT International April 1990
Concrete 42140
Leaird, J.D.; Taylor, M.A.
Acoustic emission investigation into some concrete construction problems Journal of Acoustic Emission, Vol. 8, Nos. 1-2, pp. 5322-5325 (Jan. Jun. 1989) Special Supplement - Extended Summaries of Papers to be presented at the World Meeting on Acoustic Emission, Charlotte, North Carolina, USA, 20-23 Mar. 1989 The construction industry would benefit greatly from a cost effective method of increasing the crack resistance of structural concrete and for the early detection of reactive aggregates. One method proposed to achieve the first objective is to add polypropylene fibers to the concrete. A series of beams were manufactured with polypropylene fibers added and a series without the fibers. These beams were tested in four point loading and the acoustic emission activity from each beam was measured during the load test. The plain concrete beams had 2 to 3 times the acoustic emission activity of the fiber reinforced beams. The results of tests to detect the presence of reactive aggregates are also reported. 41956
Ohtsu, M.; Sakimoto, T.; Kawai, Y.; Yuji, S.
Evaluation of concrete structure deterioration via AE observation of core tests Journal of Acoustic Emission, Voi. 7, No. 4, pp. 167-172 (Oct-Dec. 1988) An AE technique is proposed to evaluate the deterioration of concrete structures by means of tests of core-drilled samples. AE activity during a uniaxial compressive test is quantitatively analyzed based on the rate process theory. In the case of deteriorated concrete, AE events occur actively due to existing critical mierocracks even at low stress level of uniaxial loading. In contrast, AE activity in well- conditioned concrete is only observed just prior to final failure. The discrepancy of these AE activities is reasonably represented by the value of "a" in the rate process theory. To gauge the applicability of the procedure and correlate the deterioration of concrete and the value of "a", fatigue experiments of reinforced concrete slabs were performed and core samples were extracted. The proposed technique is tested by core samples with controlled damage. Results show great promise. 41953
Henkel, D.P.; Wood, J.D.
Acoustic emission testing of flexed concrete beams reinforced with bonded surface plates Journal of Acoustic Emission, Vol. 8, Nos. 1-2, pp. 5318-5321 (Jan. Jun. 1989). Special Supplement - Extended Summaries of Papers to be presented at the World Meeting on Acoustic Emission, Charlotte, North Carolina, USA, 20-23 Mar. 1989 A preliminary study is presented of the acoustic emission (AE) response of stressed concrete beams used in structural engineering subject to fracturing under four point bending. The four concrete members in the study had epoxy bonded thin plates of steel, fibre#ass, carbon and aramid fibre composites. AE activity was correlated to changes in effective beam modulus, in an attempt to identify AE fracture sources in the beam, and characterize AE signal changes induced by the different plate materials. AE is shown to be a useful method of modelling concrete damage. 41895
Ohtsu, M.
Source inversion of acoustic emission for the determination of crack kinematics and kinetics Journal of Acoustic Emission, Voi. 8, Nos. 1-2, pp. 5162-5165 (Jan. Jun. 1989). Special Supplement - Extended Summaries of papers to be presented at the World Meeting on Acoustic Emission, Charlotte, North Carolina, USA, 20-23 Mar. 1989 In the present paper, the determination of crack kinematics and kinetics is reported, as a source inversion procedure of AE. The proposed procedure is applied to AE waveforms in pull-out tests of anchor-holt from concrete block. 41866
Vogel, C.B.; Davis, M.; Guy, J.O.
Method for monitoring the goodness of the cement bond to a borehole casing
110
U.S. Patent No. 4,809,237 (28 Feb. 1989) The quality of cement bonds in borehole casings can be tested using this new method. A logging tool incorporating an acoustic transmitter and receiver is lowered into the borehole. Acoustic radiation from the transmitter is used to insonify the casing and the receiver detects the converted-compressional waves from the casing. 41763
Kwasi, B.-T.
Evaluation of layer moduli in flexible pavement systems using nondestructive and penetration testing methods Dissertation Abstracts International, Vol. 49, No. 8, p. 3337 (Feb. 1989) A research study was conducted to develop procedures for the evaluation of layer moduli in flexible pavement systems using in situ non- destructive (NDT) and penetration tests. The Bitumen Structure Analysis in Roads (BISAR) elastic layer computer program was used to simulate Dynaflect and Falling Weight Deflectometer (FWD) load- deflection response for typical flexible pavements in the state of Florida. A field testing program consisting of Dynaflect, FWD, cone penetration, Marchetti Dilatometer, and plate bearing tests was conducted on fifteen pavement sections in the state of Florida. Cores of the asphalt concrete pavement were collected for laboratory low- temperature theology tests. This provided a reliable and effective method of predicting the asphalt concrete modulus. 41758
Bungey, J.H.
The testing of concrete in structures Surrey University Press, 228pp. (1989) In this second edition of the book, the author speculates upon possible reasons for the deterioration of the ever growing number of concrete structures. Advances made over the last decade, are outlined for the techniques, equipment and methods of inspection of concrete structures. The book emphasises the need for suitably planned testing by plant engineers and provides an overview of testing concrete structures for non-specialist engineers. The procedures, scope and limitations of available test methods are outlined. 41730
Amoco Corporation
Method and apparatus for determining cement conditions U.S. Patent No. 4,802,145 (31 Jan. 1989) Thickness of the cement around wellbore casings can be determined with this device. Acoustic transducers are set at predetermined distances from each other in contact with the interior surface of the casing. The time that an acoustic pulse takes to travel from one transducer to its neighbour provides a measure of cement thickness. 41728
Western Atlas International, Inc.
System for acoustically determining the quality of the cement bond in a cased borehole U.S. Patent No. 4,805,156 (t4 Feb. 1989) This acoustic logging tool can be used to determine the quality of the bond between a borehole wall and its cement casing. A sonde with extendable pads for contact with the surrounding casing is lowered into the borehole. Transducers, arrayed in fours consisting of two transmitters of ultrasonic pulses and two receivers, are disposed on the outer surfaces of the pads. Compensated attenuation between pairs of transmitter and receiver transducers is used to determine the cement bond quality between adjacent transducers. 41646
Stockman, A; Mathieu, P.; Nicholson, P.S.
Ultrasonic characterization of model defects in ceramics (Part 3): spherical inclusions in opaque crystallized glass - theory and practice Materials Evaluation, Vol. 47, No. 3, pp. 358-362 (Mar. 1989) The model for scattering of 25 MHz pulsed focused ultrasound from spherical inclusions in the size range of 50-200 micrometres is compared with actual results for oxide inclusions in crystallized glass. Spherical oxide inclusions are examined in transparent, opaque, crystallized, and partially opaque glass. Signal analysis of the sound waves from inhomogeneities of known size and
NDT International April 1990