Journal articles: 'Coupon Tests'

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Nikhamkin, M. S., N. A. Sazhenkov, and D. Samodurov. "Fatigue Testing Method of Test Coupon and Structurally Equivalent Samples of Carbon Fiber Reinforced Polymer for Gas Turbine Engine Parts and Assemblies." Solid State Phenomena 284 (October 2018): 43–47. http://dx.doi.org/10.4028/www.scientific.net/ssp.284.43.

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The carbon fiber reinforced polymer composite are widely used in industry as major structural materials. They represent the greatest interest for the production of gas turbine engines parts because of their high specific strength. But before adaptation these materials into the structure, it is necessary to conduct a number of tests, both on test coupon and on structurally equivalent samples for determining physical, in particular, fatigue properties of these materials. However, the high cost of manufacturing coupons for such tests has a negative impact on the adaptation of carbon fiber reinforced polymer composite into the composition of final products. In this paper it is presented a method for fatigue tests of test coupon and structurally equivalent samples of carbon fiber reinforced polymer, aimed at reducing the consumption of coupons which are necessary for obtaining fatigue properties. Based on the developed method, a series of carbon fiber coupons was tested and the fatigue limit was obtained. At the same time, the use of coupons was minimized.

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J. Kitchen, Philip, Sharifah Faridah Syed Alwi, Norbani Che-Ha, and Pei Yee Lim. "Coupon redemption behaviour: a Malaysian cross-segment investigation." Marketing Intelligence & Planning 32, no. 1 (January 28, 2014): 66–88. http://dx.doi.org/10.1108/mip-05-2013-0089.

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Purpose – The purpose of this paper is to examine differing attitudinal characteristics (attitude and subjective norms) and perceptions of coupon characteristics (coupon value and coupon expiration date) towards coupon redemption based on psychological and demographic segments of consumers who may well differ in their purchase motivations and accompanying decision making. Design/methodology/approach – Following a detailed literature review, the characteristics are examined by means of a structured questionnaire administered via “mall intercept” to a convenience sample in major shopping areas in Malaysia. Findings – Following a variety of statistical tests, the findings support the use of coupon proneness, value consciousness, price consciousness and brand involvement as separate variables underpinning coupon usage propensity and indicated the value of coupons if used judiciously in relation to pre-identified segments. Research limitations/implications – The limitations associated with convenience sampling apply here, that is the findings cannot be generalised. Practical implications – The basis for sound parameters for the use of coupons are of value to marketing management. Originality/value – The paper offers an unique insight into coupon propensity and usage from a little-known economy. Its value lies in the degrees of support offered to findings from more advanced economies and a basis for differentiation in the Malaysian context.

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Huang, Yuner, and Ben Young. "The art of coupon tests." Journal of Constructional Steel Research 96 (May 2014): 159–75. http://dx.doi.org/10.1016/j.jcsr.2014.01.010.

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Freeman, R. A., and D. C. Silverman. "Technical Note:Error Propagation in Coupon Immersion Tests." CORROSION 48, no. 6 (June 1992): 463–66. http://dx.doi.org/10.5006/1.3315961.

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Sunar Bükülmez, Pınar, and Oguz C. Celik. "Pre and post-fire mechanical properties of structural steel and concrete in steel-concrete composite cellular beams." MATEC Web of Conferences 282 (2019): 02054. http://dx.doi.org/10.1051/matecconf/201928202054.

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This paper presents an experimental investigation into possible variations of mechanical properties of structural steel and concrete in composite cellular beams exposed to ISO 834 fire and cooled down phases. Four full-scale fire tests were performed on protected and unprotected beams under assumed service loads. Tensile stress-strain behavior of steel coupons taken from the beams and compressive strengths of concrete cores taken from the reinforced concrete slabs are studied. Material coupon tests for steel are carried out as per TS EN ISO 6892-1. As for the concrete, compression tests were conducted. Coupon test results reveal that, after fire testing, a maximum reduction ratio of 65% in ultimate strain is obtained for the unprotected beam samples. This indicates that the reductions in the mechanical properties of steel in the protected beams are much less when compared to those of the unprotected beams. It is also found that the maximum increase in post-fire strength/pre-fire strength ratios for concrete is 11% for the unprotected beam, while a 20 % decrease is recorded for water based protected cellular beam. For the protected specimens, the RC slabs were exposed to higher temperatures, and the compressive strength of concrete after testing was lower than that of the unprotected beam slabs.

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Clay, Stephen B., and Philip M. Knoth. "Experimental results of fatigue testing for calibration and validation of composite progressive damage analysis methods." Journal of Composite Materials 51, no. 15 (September 16, 2016): 2083–100. http://dx.doi.org/10.1177/0021998316670132.

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The Air Force Research Laboratory led a research effort to benchmark the accuracy of static and fatigue predictions of several emerging composite progressive damage analysis techniques. The static portion of this technical effort is described in detail in a previous special issue of the Journal of Composite Materials. This paper provides the details of the fatigue experiments that were conducted to calibrate and validate the computational models. Initially, in-plane and out-of-plane S–N curves were generated through coupon tests that were performed on unidirectional laminae. The challenges experienced during fatigue testing of in-plane, matrix-dominated unidirectional coupon specimens are presented in detail. The higher fidelity test data from the fiber-dominated and out-of-plane experiments are also included in this paper. Following the calibration experiments, a series of tension–tension fatigue validation tests were conducted on open-hole coupons with three different stacking sequences. Each specimen was cycled to a pre-determined number of fatigue cycles, followed by static residual strength tests in both tension and compression. This paper provides the stress–strain responses of these validation tests as well as high-resolution X-ray computed tomography images of the subsurface damage as a function of cycles. Seven analysis teams used these test results to calibrate their models and to benchmark the accuracy of their predictions of damage and residual mechanical properties.

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Clay, Stephen B., and Philip M. Knoth. "Experimental results of quasi-static testing for calibration and validation of composite progressive damage analysis methods." Journal of Composite Materials 51, no. 10 (July 15, 2016): 1333–53. http://dx.doi.org/10.1177/0021998316658539.

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The Air Force Research Laboratory directed a research program to evaluate nine different composite progressive damage analysis methods under both quasi-static and fatigue loading. This paper describes the coupon tests that were performed at the Air Force Research Laboratory for calibration and validation of the methods under quasi-static conditions. The basic elastic and failure properties of unidirectional IM7/977-3 graphite/epoxy were first determined in order to properly calibrate the models. Validation tests were then performed on unnotched and open-hole coupons with three different laminate stacking sequences under both tension and compression loading conditions. This paper summarizes these experimental results and provides X-ray computed tomography images at subcritical load levels.

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Gallagher, Joseph P., and Lorrie Molent. "Effect of Load Spectra and Stress Magnitude on Crack Growth Behavior Variability from Typical Manufacturing Defects." Advanced Materials Research 891-892 (March 2014): 100–105. http://dx.doi.org/10.4028/www.scientific.net/amr.891-892.100.

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DSTO conducted a comprehensive series of fatigue coupon tests as part of the fatigue life substantiation of the RAAF F/A-18 Hornet. The study employed five spectra which were applied to flat aluminium alloy 7050-T7451 coupons to determine the effects of manufacturing discontinuities and stress magnitude on the fatigue nucleation and crack growth behavior. Crack growth behavior was established using optical microscopy and scanning electron fractography, measuring crack sizes greater than approximately 0.05 mm. This paper reports the fraction of life to failure as well as the probability of occurrence of a crack with a defined size.

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Xu, Bo, Junwu Xia, Renwei Ma, Jian Wang, Xiaomiao Chen, Hongfei Chang, and Lihai Zhang. "Investigation on True Stress-Strain Curves of Flat and Corner Regions of Cold-Formed Section Using 3D Digital Image Correlation Method." Advances in Civil Engineering 2019 (December 16, 2019): 1–18. http://dx.doi.org/10.1155/2019/3138176.

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The true stress-strain curve is the critical method to describe the practical material mechanical performance and the essential precondition to develop the advanced numerical simulation. Experimental, analytical, and numerical procedures were performed in present research to investigate the true stress-strain curves of flat and corner regions of the cold-formed channel section. The coupon tests with the 3D digital image correlation system were conducted on flat and corner specimens to directly obtain the true stress-strain curves. The experimental results indicate that the tensile secondary-hardening phenomenon at the plastic strain stage was observed in the true stress-strain curves of flat coupons, and initial strain hardening behavior was produced in that of corner coupons. Flat region exhibits a significant improvement of true ultimate strength compared to the engineering value. The stress status of the corner region is developed to ultimate strength at the early strain phase and exhibits a slight increase compared with the nominal values at the plastic phase. Cold-rolling action limits the ductility performance of the corner region, which highly restrains the tensile strain hardening at the plastic condition. Thus, the true yielding strength of the corner region is obviously higher, but the true ultimate strength is significantly lower than that of the flat region. Together with the optical measuring results, a trilinear model with two-stage strain hardening and a simplified trilinear models were established for describing the true stress-strain curves of flat and corner regions, respectively. The load-displacement curves from numerical simulations fit very well with those of coupon tests, which validate the reliability of the optic measurement and the dependability of the simplified constitutive models.

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Park, Chan Y., Nam H. Kim, and Raphael T. Haftka. "How coupon and element tests reduce conservativeness in element failure prediction." Reliability Engineering & System Safety 123 (March 2014): 123–36. http://dx.doi.org/10.1016/j.ress.2013.10.012.

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Cui, Hao, Yusuf Mahadik, Stephen R. Hallett, Ivana K. Partridge, Giuliano Allegri, Sathiskumar A. Ponnusami, and Nik Petrinic. "Coupon scale Z-pinned IM7/8552 delamination tests under dynamic loading." Composites Part A: Applied Science and Manufacturing 125 (October 2019): 105565. http://dx.doi.org/10.1016/j.compositesa.2019.105565.

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Cañas, José, Luis Távara, Antonio Blázquez, and Alejandro Estefani. "Overview of Gc Tests Used to Evaluate Composite–Composite Adhesive Joints." Journal of Multiscale Modelling 10, no. 03 (September 2019): 1842002. http://dx.doi.org/10.1142/s1756973718420027.

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The quality of composite–composite bonded joints is a very important issue for industries, especially for the aerospace sector. A deficient joint may stop the manufacturing process and its repairing may include very high costs. Nowadays, the quality of the joint is obtained by means of interlaminar fracture toughness tests, estimating the [Formula: see text] value (Energy Release Rate used to produce crack propagation) over coupons with (theoretically) the same conditions as those included in an actual part. Usually, [Formula: see text] is obtained by means of a Double Cantilever Beam (DCB) test. Although DCB is the reference test, it may present some drawbacks when a non-symmetrical coupon is used and when the adherents stiffness is low. An alternative to DCB is the Climbing Drum Peel (CDP) test which is able to address some of the DCB drawbacks. Nevertheless, both tests need the use of a universal testing machine, then they cannot be done in situ. In the present investigation, DCB and CDP main characteristics are analyzed and a new device, called Horizontal Drum Peel (HDP), which includes the advantages of previous tests and the possibility to perform the test over an actual part is presented.

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Kang, Lan, Bin Wu, Xinpei Liu, and Hanbin Ge. "Experimental study on post-fire mechanical performances of high strength steel Q460." Advances in Structural Engineering 24, no. 12 (May 16, 2021): 2791–808. http://dx.doi.org/10.1177/13694332211010601.

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A series of experimental tests for investigating the post-fire mechanical (PFM) and post-fire fracture (PFF) performances of high strength steel Q460 are reported in this paper. All Q460 coupon specimens are heated up to a designated temperature which is selected from 100 to 900°C and then cooled down naturally to room temperature. Tensile tests are conducted to obtain their completely full-range post-fire stress-strain curves and the corresponding mechanical properties. The obtained experimental results show that with an increase in the heating temperature, the post-fire yield strength and ultimate strength of the Q460 structural steel decrease particularly when the heating temperature is over 650°C, but the post-fire elongation enhances. Ductile fracture behaviour of the coupon specimens under axial tensile loading can also be observed through the tensile coupon tests. The obtained experimental data are compared with the other results found in the open literatures on Grade 460 high strength steel. Based on a wider range of experimental data sets, predictive equations for evaluating the PFM properties of Grade 460 high strength steel are proposed. The experimental results presented in this study will provide benchmark data for the future calibration of complex ductile fracture parameters applied in numerical simulation.

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Shi, Jia Wei, Hong Zhu, Zhi Shen Wu, and Gang Wu. "Durability of BFRP and Hybrid FRP Sheets under Freeze-Thaw Cycling." Advanced Materials Research 163-167 (December 2010): 3297–300. http://dx.doi.org/10.4028/www.scientific.net/amr.163-167.3297.

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Coupon tests were conducted to investigate the mechanical characteristics of basalt FRP (BFRP) sheet, basalt-carbon hybrid FRP sheets and the corresponding epoxy rein under the effect of freeze-thaw cycling. FRP sheets and epoxy rein coupons were subjected to up to 200 and 250 freeze-thaw cycles respectively. Test parameters included the number of freeze-thaw cycles and the types of FRP composites. Test results show that (1) BFRP sheet perform better than CFRP or GFRP sheets under high freeze-thaw cycles; (2) exposed hybrid FRP sheets not only show very little loss in mechanical properties, but also contribute to the stability of test data; (3) mechanical properties of rein epoxy decrease significantly with increasing freeze-thaw cycles.

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van Leeuwen, Hans, Don van Delft, John Heijdra, Henk Braam, Eric R. Jørgensen, Denja Lekou, and Pantelis Vionis. "Comparing Fatigue Strength From Full Scale Blade Tests With Coupon-Based Predictions." Journal of Solar Energy Engineering 124, no. 4 (November 1, 2002): 404–11. http://dx.doi.org/10.1115/1.1509463.

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In order to get a deeper understanding of the blade-to-blade variations and to determine the statistical distribution of the fatigue strength of rotor blades, 37 small rotor blades have been tested in static and fatigue loading. The blades are 3.4 m commercially available blades adapted to the needs of the project. In addition to these blade tests, coupons of the blade material have been tested. The tests have encompassed static flapwise bending tests, flapwise fatigue tests at two different sections of the blade, and edgewise fatigue tests. Since some blades could be re-used after a first test, a total number of 42 blade tests has been carried out in three different testing laboratories. The blades showed large deformation, development of creep and stiffness reduction. After correction for these phenomena, the fatigue strength of the blades was predicted very well by the classical Goodman relation using the well-known slope parameter of 10.

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AOKI, HIROFUMI, and MASAYUKI MASUDA. "STATISTICAL INVESTIGATION ON MECHANICAL PROPERTIES OF STRUCTURAL STEEL BASED ON COUPON TESTS." Journal of Structural and Construction Engineering (Transactions of AIJ) 358 (1985): 94–105. http://dx.doi.org/10.3130/aijsx.358.0_94.

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Kosaka, Yoji, and Phani Gudipati. "Superplasticity and Characterization of TIMETAL^®54M Sheets." Materials Science Forum 838-839 (January 2016): 190–95. http://dx.doi.org/10.4028/www.scientific.net/msf.838-839.190.

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TIMETAL®54M (Ti-5Al-4V-0.75Mo-0.5Fe) or Ti-54M is an alpha/beta titanium alloy developed by TIMET. Earlier technical publications have confirmed that laboratory scale Ti-54M sheets exhibit superior SPF capabilities compared to Ti-6Al-4V (Ti-64), in terms of flow stress, temperature and strain rate. Various gauges of these sheets, ranging from 0.64mm to 4.57mm, were produced on a production scale using TIMET patented process. Coupon tests were performed in accordance to ASTM E2448 and the results confirmed that the SPF capability of these sheets at a temperature as low as 774°C, which is a significant cost benefit in the SPF fabrications. The present paper discussed basic properties of Ti-54M sheets along with SPF coupon tests results showing lower temperature superplasticity. The low temperature superplasticity of Ti-54M is due to the combined effect of alloying elements and finer primary alpha particle size.

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Stevanovic, Momcilo, Milan Gordic, Daniela Sekulic, and Isidor Djordjevic. "The effect of edge interlaminar stresses on the strength of carbon/epoxy laminates of different stacking geometry." Journal of the Serbian Chemical Society 71, no. 4 (2006): 421–31. http://dx.doi.org/10.2298/jsc0604421s.

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The effect of edge interlaminar stresses on strength of carbon/epoxy laminates of different stacking geometry: cross-ply, quasi-isotropic and angle-ply laminates with additional 0? and 90? ply was studied. Coupons with two widths of laminates with an inverse stacking sequence were tested in static tensile tests. The effect of edge interlaminar stresses on strength was studied, by comparing the values of the tensile strength of laminate coupons of the same width with an inverse stacking sequence, as well as, by comparing the values of the tensile strength of the same lay-up laminate coupons but of different widths. The edge effects were analyzed by observing failure, identifying the interlayer where axial cracks at the free edge were initiated or inhibited and by computing interlaminar stresses and strains in the interlayer near the free edge of the coupon. The established edge effect was first correlated to the sign of the normal edge interlaminar stress. The extent of the edge effect was then successfully correlated to the edge interlaminar normal stress normalized to the size of the edge boundary region in which the stress appeared.

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Hale, J. M., and A. G. Gibson. "Coupon Tests of Fibre Reinforced Plastics at Elevated Temperatures in Offshore Processing Environments." Journal of Composite Materials 32, no. 4 (February 1998): 387–404. http://dx.doi.org/10.1177/002199839803200404.

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Hale, J. M., and A. G. Gibson. "Coupon Tests of Fibre Reinforced Plastics at Elevated Temperatures in Offshore Processing Environments." Journal of Composite Materials 32, no. 6 (March 1998): 526–43. http://dx.doi.org/10.1177/002199839803200602.

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Lenzi, F., A. Riccio, A. Clarke, and R. Creemers. "Coupon Tests on z-Pinned and Unpinned Composite Samples for Damage Resistant Applications." Macromolecular Symposia 247, no. 1 (February 2007): 230–37. http://dx.doi.org/10.1002/masy.200750126.

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Xu, Lin, Si Yang Li, and Ming Biao Xu. "A Case Study on Inner Corrosion of 3%Cr Casing Steel in the CO₂ Environments." Applied Mechanics and Materials 872 (October 2017): 38–42. http://dx.doi.org/10.4028/www.scientific.net/amm.872.38.

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Understanding inner corrosion property of casing steel is fundamental to safe and economic exploitation of oil & gas. In this present work, a series of corrosion tests were conducted on 3%Cr coupons derived from 9-5/8” casing. Analyses of weight loss, product morphology and composition were carried out, to investigate the corrosion behaviors caused by sweet CO2. Analysis on the weight loss showed that, with an increment of temperature from 45°C to 105°C, the corrosion rate of 3%Cr coupon firstly ascends and then arrives to the maximum at 65°C. SEM analysis demonstrated the formation of a compact corrosion product layer on the specimen surface. While increasing the exposed time increases, the corrosion rate gradually descends. The main compositions of corrosion product are Fe-Cr and Cr5O12, which can effective hinder corrosion reaction in the CO2 environment.

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Vassilopoulos, Anastasios P., Efstratios F. Georgopoulos, and Vasileios Dionysopoulos. "Modelling Fatigue Life of Multidirectional GFRP Laminates under Constant Amplitude Loading with Artificial Neural Networks." Advanced Composites Letters 15, no. 2 (March 2006): 096369350601500. http://dx.doi.org/10.1177/096369350601500201.

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An artificial neural network has proven to be a sufficient tool for modelling fatigue life of multidirectional composite laminates made of Glass Fibre Reinforced Plastic (GFRP) composite materials and tested under constant amplitude loading patterns. Modelling efficiency of the network was satisfactory for both on- and off-axis coupons life, irrespective of test conditions, i.e., R-ratio that defines the developed stress state on the coupon. Tension-Tension, Compression-Compression and even Tension-Compression loading patterns were investigated and modelling accuracy of the proposed ANN model was validated. The main benefit that this new modelling tool brings is that only a small portion, in the order of 40%-50%, of the experimental data is needed for the whole analysis and thus, expensive and time consuming tests needed for the establishment of S-N curves could be eliminated without any significant loss of accuracy.

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Fan, Sheng Ping, Fang Lin Zha, and Shu Nan Cao. "The Research on Film-Forming Performance of a New Kind of Compound Inhibitor." Advanced Materials Research 550-553 (July 2012): 40–45. http://dx.doi.org/10.4028/www.scientific.net/amr.550-553.40.

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The film-forming effect of a new kind of compound inhibitor at high temperature was researched, with taking pure octadecyamine and pure imidazoline as comparison tests. Coupon test has been taken with autoclave simulating the on-site water-vapor environment; the film-forming effect of the coupon has been evaluated by hydrophobic test, acid copper sulfate drip test ,AC impedance test and scanning electron microscope(SEM) test. The GC-MS test was taken to analysis decomposition products of the compound inhibitor. The results show that the compound inhibitor can film well, and decomposition product doesn’t contain low molecular weight organic acids and other harmful ingredients. The compound inhibitor can applied into practice safely and efficiently.

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Wu, Guo, Shi, Li, and Lu. "Laboratory-Based Investigation into Stress Corrosion Cracking of Cable Bolts." Materials 12, no. 13 (July 3, 2019): 2146. http://dx.doi.org/10.3390/ma12132146.

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Cable-bolt failures due to stress corrosion cracking (SCC) could significantly compromise the sustainability and long-term stability of underground constructions. To fully understand the SCC of cable bolts, a two-step methodology was implemented: (i) long-term cable-bolt coupon tests using mineralogical materials collected from underground mines; and (ii) accelerated full-scale cable-bolt tests using an acidified solution. In the long-term tests, a novel three-point bending coupon was designed. The effects of mineralogical materials on SCC were evaluated under the simulated underground bolting conditions through the application of “corrosion cells”. For accelerated tests, SCC resistance of different type of cable bolts was examined using the new designed tensile-loading apparatus under the periodically increasing strain-rate loading mechanism. It was identified that mineralogical materials and applied stress intensity accelerated the corrosion process of the cable bolts. The number of wires and wire surface conditions in different types of cable bolt directly affected SCC susceptibility. The cable bolts with a greater number of wires provided higher resistance to SCC. The developed experimental methodologies can be applied to study SCC in other reinforcement materials and the results can be used to design optimal support systems in different environmental and geotechnical conditions.

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Gyekenyesi, A. L. "Isothermal Fatigue Behavior and Damage Modeling of a High Temperature Woven PMC." Journal of Engineering for Gas Turbines and Power 122, no. 1 (October 20, 1999): 62–68. http://dx.doi.org/10.1115/1.483176.

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This study focuses on the fully reversed fatigue behavior exhibited by a carbon fiber/polyimide resin woven laminate at room and elevated temperatures. Nondestructive video edge view microscopy and destructive sectioning techniques were used to study the microscopic damage mechanisms that evolved. The elastic stiffness was monitored and recorded throughout the fatigue life of the coupon. In addition, residual compressive strength tests were conducted on fatigue coupons with various degrees of damage as quantified by stiffness reduction. Experimental results indicated that the monotonic tensile properties were only minimally influenced by temperature, while the monotonic compressive and fully reversed fatigue properties displayed greater reductions due to the elevated temperature. The stiffness degradation, as a function of cycles, consisted of three stages; a short-lived high degradation period, a constant degradation rate segment covering the majority of the life, and a final stage demonstrating an increasing rate of degradation up to failure. Concerning the residual compressive strength tests at room and elevated temperatures, the elevated temperature coupons appeared much more sensitive to damage. At elevated temperatures, coupons experienced a much larger loss in compressive strength when compared to room temperature coupons with equivalent damage. The fatigue damage accumulation law proposed for the model incorporates a scalar representation for damage, but admits a multiaxial, anisotropic evolutionary law. The model predicts the current damage (as quantified by residual stiffness) and remnant life of a composite that has undergone a known load at temperature. The damage/life model is dependent on the applied multiaxial stress state as well as temperature. Comparisons between the model and data showed good predictive capabilities concerning stiffness degradation and cycles to failure. [S0742-4795(00)01001-2]

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IWATA, Yoshihiro, Tadashi ISHIHARA, Akiyoshi MUKAI, Isao NISHIYAMA, and Hirofumi AOKI. "RELATION BETWEEN UNIFORM ELONGATION AND RUPTURE ELONGATION AT COUPON TENSION TESTS OF STRUCTURAL STEEL." Journal of Structural and Construction Engineering (Transactions of AIJ) 78, no. 683 (2013): 223–32. http://dx.doi.org/10.3130/aijs.78.223.

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Huang, Zhenyu, Wei Zhang, Xudong Qian, Zhoucheng Su, Dinh-Chi Pham, and Narayanaswamy Sridhar. "Fatigue behaviour and life prediction of filament wound CFRP pipes based on coupon tests." Marine Structures 72 (July 2020): 102756. http://dx.doi.org/10.1016/j.marstruc.2020.102756.

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Helmi, Karim, Amir Fam, and Aftab Mufti. "Fatigue Life Assessment and Static Testing of Structural GFRP Tubes Based on Coupon Tests." Journal of Composites for Construction 12, no. 2 (April 2008): 212–23. http://dx.doi.org/10.1061/(asce)1090-0268(2008)12:2(212).

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Jia, Liang-Jiu, Tsuyoshi Koyama, and Hitoshi Kuwamura. "Prediction of cyclic large plasticity for prestrained structural steel using only tensile coupon tests." Frontiers of Structural and Civil Engineering 7, no. 4 (October 25, 2013): 466–76. http://dx.doi.org/10.1007/s11709-013-0219-5.

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Correa, E., A. Barroso, M. D. Pérez, and F. París. "Design for a cruciform coupon used for tensile biaxial transverse tests on composite materials." Composites Science and Technology 145 (June 2017): 138–48. http://dx.doi.org/10.1016/j.compscitech.2017.03.045.

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Won, Moon C., and Chien N. Fu. "Evaluation of Laboratory Procedures for Aggregate Polish Test." Transportation Research Record: Journal of the Transportation Research Board 1547, no. 1 (January 1996): 23–28. http://dx.doi.org/10.1177/0361198196154700104.

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Years of polish value testing at the Texas Department of Transportation have revealed that the test results are highly sensitive not only to aggregate textures, but also to other factors, resulting in large variabilities in test results. For the test results to be purely indicative of aggregate textures, other factors need to be tightly controlled. The primary objectives of the study were to address those factors and to improve the testing procedures to minimize variability. All possible factors were identified and pilot tests were conducted to eliminate factors with nonsignificant effects. Detailed tests were conducted to evaluate the effects of the remaining factors. Among the factors investigated that were found to be significant in this study were curvature of the coupons, the length of the slider contact path, slider rubber characteristics, aggregate particle arrangement, normal slider load, and aggregate selection technique. To minimize the variability, the following emphasis is recommended: (a) measure the coupon curvature before testing, (b) control the length of the slider contact path, (c) maintain the normal slider load between 2500 and 2600 g, and (d) select aggregate particles by splitting, rather than handpicking, for mineralogically heterogeneous aggregates.

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James, Robin, Roshan Prakash Joseph, and Victor Giurgiutiu. "Impact Damage Ascertainment in Composite Plates Using In-Situ Acoustic Emission Signal Signature Identification." Journal of Composites Science 5, no. 3 (March 12, 2021): 79. http://dx.doi.org/10.3390/jcs5030079.

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Barely visible impact damage (BVID) due to low velocity impact events in composite aircraft structures are becoming prevalent. BVID can have an adverse effect on the strength and safety of the structure. During aircraft inspections it can be extremely difficult to visually detect BVID. Moreover, it is also a challenge to ascertain if the BVID has in-fact caused internal damage to the structure or not. This paper describes a method to ascertain whether or not internal damage happened during the impact event by analyzing the high-frequency information contained in the recorded acoustic emission signal signature. Multiple 2 mm quasi-isotropic carbon fiber reinforced polymer (CFRP) composite coupons were impacted using the ASTM D7136 standard in a drop weight impact testing machine to determine the mass, height and energy parameters to obtain approximately 1” impact damage size in the coupons iteratively. For subsequent impact tests, four piezoelectric wafer active sensors (PWAS) were bonded at specific locations on each coupon to record the acoustic emission (AE) signals during the impact event using the MISTRAS micro-II digital AE system. Impact tests were conducted on these instrumented 2 mm coupons using previously calculated energies that would create either no damage or 1” impact damage in the coupons. The obtained AE waveforms and their frequency spectrums were analyzed to distinguish between different AE signatures. From the analysis of the recorded AE signals, it was verified if the structure had indeed been damaged due to the impact event or not. Using our proposed structural health monitoring technique, it could be possible to rapidly identify impact events that cause damage to the structure in real-time and distinguish them from impact events that do not cause damage to the structure. An invention disclosure describing our acoustic emission structural health monitoring technique has been filed and is in the process of becoming a provisional patent.

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Starace, F., SD Orlando, M. Guida, and F. Marulo. "Experimental study of a virtual allowables approach for the design of composite aircraft structures." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 235, no. 14 (July 2021): 2529–41. http://dx.doi.org/10.1177/0954406220987862.

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Statistically derived allowables are representative for the behavior of a composite material system in a given structural context where data variability needs to be contemplated. In particular, they define the strength of the material as characterized by various coupon tests according to ASTM standard procedure subjected to the actual manufacturing process and layup stacking sequences. The current paper presents a detailed comparison between virtual allowables predictions obtained using MSC Digimat and the experimentally determined values of a certified material backed up by a 3x2x3 (batch/panel/specimen) stochastic approach. Tests generate the required data for building material model ab initio of carbon fibers reinforced epoxide resin in form of 2x2 twill woven fabric used for qualifying an innovative composite wing for the Next Generation Tilt Rotor (NGCTR). Numerical models of in-plane tension, compression and shear test methods have been assembled along with an associated material model allowing numerical predictions to be validated with the coupon level experimental results as final purpose. Standard statistical model has been adopted in order to include material and manufacturing process variabilities to define B-basis allowables. The calibrated statistical FEM method performed for different layup configurations have been used to fully characterize the mechanical behavior of the analyzed CFRP material and to predict performances for thicker laminates.

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Heimbs, Sebastian, Tim Wagner, Heinz Meister, Clemens Brand, and Mircea Calomfirescu. "Bird strike on aircraft radome: Dynamic characterisation of quartz fibre composite sandwich for accurate, predictive impact simulations." EPJ Web of Conferences 183 (2018): 01007. http://dx.doi.org/10.1051/epjconf/201818301007.

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This study assesses the bird strike resistance of the satellite communication (SatCom) radome of a medium altitude, long endurance (MALE) remotely piloted aircraft system (RPAS), which is designed as a lightweight sandwich structure with thin quartz fibre composite skins and a cellular honeycomb core. In order to perform accurate, predictive numerical bird strike simulations, the building block approach was applied, involving extensive experimental characterisation and model validation of the materials and structures from simple coupon level up to full-scale radome level. Coupon tests of the quartz fibre composite skin material under high-rate dynamic loading revealed significant strain rate effects, which needed to be taken into account in the simulation model in order to predict the structural response under high-velocity bird strike loading. In summary, this work presents a systematic and detailed approach for obtaining validated modelling methods for high-velocity impact analyses, which could be used efficiently for various design and parameter studies during the development of the SatCom radome.

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Murthy, Madhav, K. Mallikharjuna Babu, and Martin Jebraj. "Effect of Volume Fraction and Resin System on Tensile, Compression and Flexural Strength of Electrical Glass Fiber Reinforced Plastic Laminate." Solid State Phenomena 287 (February 2019): 86–92. http://dx.doi.org/10.4028/www.scientific.net/ssp.287.86.

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This work deals with the experimental studies on effect of changing volume fraction and also various resin systems like Epoxy LY556, AW106 & CY230 on ultimate tensile, compression and flexural strength of a polymer matrix composite. The specimens were prepared through vacuum assisted resin transfer molding technique. The vacuum pump is a double stage rotary vacuum pump of specifications 300 lpm, 1 hp &3ph. Reinforcements of different thickness/layer of bidirectional e-glass fibers were used and the epoxy resins of varying viscosities were used. The machining of the fabricated specimens was carried out using abrasive water jet cutting facility. The test coupons were tested as per ASTM standards. Tensile, compression and flexural tests were carried out for each experiment and three trials were made for each experiment in order to arrive at the average value of tensile, compressive and flexural strength. The inferences are drawn for each type of resin system and volume fraction of the matrix and reinforcement used which helps in understanding the enhancement in ultimate strength of the test coupon under study.

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Yates, Keegan M., Amanda M. Agnew, Devon L. Albert, Andrew R. Kemper, and Costin D. Untaroiu. "Subject-specific rib finite element models with material data derived from coupon tests under bending loading." Journal of the Mechanical Behavior of Biomedical Materials 116 (April 2021): 104358. http://dx.doi.org/10.1016/j.jmbbm.2021.104358.

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Nijssen, R. P. L., D. R. V. van Delft, and A. M. van Wingerde. "Alternative Fatigue Lifetime Prediction Formulations for Variable-Amplitude Loading." Journal of Solar Energy Engineering 124, no. 4 (November 1, 2002): 396–403. http://dx.doi.org/10.1115/1.1510524.

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Accurate prediction of lifetime is an increasingly important issue for wind turbine rotor blade materials. Coupon tests with the variable-amplitude standard loading sequences for wind turbines known as WISPER and WISPERX have indicated that the coupon lifetime can be overestimated by one or two orders of magnitude using conventional lifetime prediction formulations. In the actual design, this might be compensated for by conservative design factors covering other aspects such as environmental conditions. These conventional lifetime prediction formulations use Rainflow counting of the load history, a log-log SN-curve (stress- or strain amplitude versus cycles to failure) for R = −1, a linear Goodman diagram as a constant-life diagram, and Miner summation. In this work, possible alternative fatigue formulations to improve lifetime prediction under variable-amplitude loading are investigated. Results of WISPER and WISPERX variable-amplitude tests on a material representative of wind turbine rotor blades are used. Only alternatives for the SN-curve and the constant-life diagram are investigated; Rainflow counting and Miner summation are used in all predictions discussed here. None of the investigated SN-curves unites an apparent correlation of constant-amplitude data with an accurate and/or conservative lifetime prediction, when including them in a classical linear Goodman diagram. However, the lin-log- and log-log SN-curves do yield better predictions in combination with an alternative constant-life diagram.

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Polyzois, D., P. Charnvarnichborikarn, S. Rizkalla, and C. K. Wong. "Effect of temperature and galvanization on the compressive strength of cold-formed angles." Canadian Journal of Civil Engineering 17, no. 3 (June 1, 1990): 440–51. http://dx.doi.org/10.1139/l90-048.

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An experimental program was conducted at The University of Manitoba to investigate the effect of subfreezing temperatures and galvanization on the compressive strength of cold-formed steel angles. The study involved the testing of 20 cold-formed angles, 55 × 55 × 4 mm, with a slenderness ratio of approximately 70. Equal numbers of galvanized and ungalvanized angles were tested at various temperatures ranging from −45 to 25 °C. The material properties were obtained through 48 standard tension coupon tests conducted at the same temperature range. The results showed that the capacity of the angles measured at temperatures below −40 °C was approximately 8% higher than the capacity at room temperature. Similar results were obtained during testing of the standard tension coupons where the yield and tensile strengths of the steel used were approximately 10% higher at temperatures below −40 °C than at room temperature. On the average, the ultimate capacity of galvanized angles was approximately 9% higher than that of ungalvanized angles. Although the yield strength of the corner coupons was between 13% and 27% higher than that of flat coupons tested at room temperature, the compressive strength of the full-size angles was influenced mainly by the material properties of the flat regions. A comparison of the measured and predicted capacities using the current Canadian standard and American specification indicated that the Canadian standard overestimated the ultimate capacity of the angles by as much as 37%, while the American specification underestimated the capacity by as much as 45%. Key words: angles, cold-formed, galvanized, temperature, compression, ultimate.

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Bambach, Mike R. "Direct Comparison of the Structural Compression Characteristics of Natural and Synthetic Fiber-Epoxy Composites: Flax, Jute, Hemp, Glass and Carbon Fibers." Fibers 8, no. 10 (September 28, 2020): 62. http://dx.doi.org/10.3390/fib8100062.

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Recent decades have seen substantial interest in the use of natural fibers in continuous fiber reinforced composites, such as flax, jute and hemp. Considering potential applications, it is of particular interest how natural fiber composites compare to synthetic fiber composites, such as glass and carbon, and if natural fibers can replace synthetic fibers in existing applications. Many studies have made direct comparisons between natural and synthetic fiber composites via material coupon testing; however, few studies have made such direct comparisons of full structural members. This study presents compression tests of geometrically identical structural channel sections fabricated from fiber-epoxy composites of flax, jute, hemp, glass and carbon. Glass fiber composites demonstrated superior tension material coupon properties to natural fiber composites. However, for the same fiber mass, structural compression properties of natural fiber composite channels were generally equivalent to, or in some cases superior to, glass fiber composite channels. This indicates there is substantial potential for natural fibers to replace glass fibers in structural compression members. Carbon fiber composites were far superior to all other composites, indicating little potential for replacement with natural fibers.

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Hu, Yan Qi, and Wieslaw K. Binienda. "Multiscale Modeling of a Notched Coupon Test for Triaxially Braided Composites." Key Engineering Materials 795 (March 2019): 172–79. http://dx.doi.org/10.4028/www.scientific.net/kem.795.172.

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Braided composites have been widely used in aerospace and automotive structures due to their light weight and high strength. Unlike metal or laminated composite material, the complex braided structure brings a lot of challenges when conducting numerical simulation. In this paper, a finite element analysis based meso-mechanical modeling for the two dimensional triaxially braided composite was developed. This mesoscale modeling method is capable of considering the detailed braiding geometry and architecture as well as the mechanical behavior of fiber tows, matrix and the fiber tow interface. Furthermore, a multiscale model combined both macroscale and mesoscale approaches and it is realized within LS-DYNA environment through Interface_components and Interface_linking. This combined multiscale modeling approach enables the full advantage of both the macroscale and mesoscale approaches, which can describe the details of local deformation and the global overall response features of the entire structure with the minimum computational expense. The evaluation and verification of the mesoscale approach and combined multiscale modeling method is through a notched coupon tensile tests conducted by Kohlman in both axial and transverse direction. The multiscale modeling method captures the response feature accurately so it has the ability to analyze large scale structures.

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Elfström Broo, A., B. Berghult, and T. Hedberg. "Drinking water distribution - improvements of the surface complexation model for iron corrosion." Water Supply 1, no. 3 (June 1, 2001): 11–18. http://dx.doi.org/10.2166/ws.2001.0048.

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A previously presented theory for iron corrosion in the distribution networks for drinking water, the surface complexation model, was extended by the effect of natural organic matter and redox potential. The model calculations showed good agreement with measurements of the corrosion rate as obtained from coupon tests. A theory for the relation between the dissolved iron content in the water of the distribution networks and the corrosion rate is proposed. The model calculations also showed good agreement with the measured dissolved iron content.

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Choi, Sang-Jin, Seong-Yong Jeong, Changhyun Lee, Kwon Gyu Park, and Jae-Kyung Pan. "Twisted Dual-Cycle Fiber Optic Bending Loss Characteristics for Strain Measurement." Sensors 18, no. 11 (November 16, 2018): 4009. http://dx.doi.org/10.3390/s18114009.

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The intensity-based fiber optic sensor (FOS) head using twisted dual-cycle bending loss is proposed and experimentally demonstrate. The bending loss characteristics depend on the steel wire radius, number, and distance. To determine the effects of these parameters, two samples in each of seven configuration cases of the proposed FOS head were bonded to fiber reinforced plastics coupons, and tensile and flexural strain tests were repeated five times for each coupon. The bending loss of the manufactured FOS heads was measured and converted to the tensile and flexural strain as a function of configuration cases. The measurement range, sensitivity, and average measurement errors of the tensile load and flexural strain were 4.5 kN and 1,760 με, 0.70 to 3.99 dB/kN and 0.930 to 6.554 dB/mm, and 57.7 N, and 42.6 με, respectively. The sensing range of FOS head were 82 to 138 mm according to configuration cases. These results indicate that it is possible to measure load, tensile strain, and flexural strain using the proposed FOS head, and demonstrate that the sensitivities, the operating ranges, and the sensing range can be adjusted depending on the deformation characteristics of the measurement target.

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Yarmolik, V. N., I. Mrozek, and S. V. Yarmolik. "Pseudoexhaustive memory testing based on March A type march tests." Informatics 17, no. 2 (June 26, 2020): 54–70. http://dx.doi.org/10.37661/1816-0301-2020-17-2-54-70.

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The relevance of testing of memory devices of modern computing systems is shown. The methods and algorithms for implementing test procedures based on classical March tests are analyzed. Multiple March tests are highlighted to detect complex pattern-sensitive memory faults. To detect them, the necessary condition that test procedures must satisfy to deal complex faults, is substantiated. This condition is in the formation of a pseudo-exhaustive test for a given number of arbitrary memory cells. We study the effectiveness of single and double application of tests like MATS ++, March C– and March A, and also give its analytical estimates for a different number of k ≤ 10 memory cells participating in a malfunction. The applicability of the mathematical model of the combinatorial problem of the coupon collector for describing multiple memory testing is substantiated. The values of the average, minimum, and maximum multiplicity of multiple tests are presented to provide an exhaustive set of binary combinations for a given number of arbitrary memory cells. The validity of analytical estimates is experimentally shown and the high efficiency of the formation of a pseudo-exhaustive coverage by tests of the March A type is confirmed.

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Ben Azzouna, Mouldi, Jean-Noël Périé, Jean-Mathieu Guimard, François Hild, and Stéphane Roux. "On the Identification and Validation of an Anisotropic Damage Model Using Full-field Measurements." International Journal of Damage Mechanics 20, no. 8 (January 13, 2011): 1130–50. http://dx.doi.org/10.1177/1056789510395555.

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Two different mechanical tests are performed on a laminated composite coupon to induce an anisotropic damage affecting essentially shear modulus softening. The first test is a uniaxial tension loading on a straight coupon, which is used to evaluate the damage law using a conventional approach, while the second contains a notch that enhances dramatically the strain (and hence damage) heterogeneity. A global digital image correlation approach is used to quantify the kinematic fields all along the loading path of the second experiment. Displacement fields are hence evaluated based on a finite element type discretization. A further exploitation based on the reconditioned equilibrium gap method (and without any further information) gives access to a quantitative measurement of the damage law. The latter approach makes use of a finite element model based on the very same mesh and element shape function. This full-field-based identification method compares very well with traditional techniques, up to the stage where macroscopic localization prevents their subsequent exploitations. Moreover, it is shown that neither the type of mechanical test, nor the discretization of the displacement field, affects the identification of the damage law.

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Tomlinson, Scott M., and Roberto A. Lopez-Anido. "Scale and manufacturing effects on tensile strength of marine grade sandwich composite panel joints." Journal of Sandwich Structures & Materials 22, no. 6 (August 9, 2018): 1983–2008. http://dx.doi.org/10.1177/1099636218792676.

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In this article, scale and manufacturing effects on the tensile strength of marine grade sandwich composite panels and joints are investigated to aid in the fabrication of large modular ship hulls. This is done by researching transverse sandwich composite joint design, experimental tension methods, and scale and manufacturing effects on tensile strength. Three scales are utilized in this investigation of tension characteristics: coupon scale, table-top single panel fabrication scale, and in position mock-up full-size fabrication scale. First, material properties are gathered through industry standard coupon scale fabrication and testing. Next, a single-infusion baseline panel along with two ship hull transverse joint designs are chosen, fabricated, tested, and compared at single panel scale. These tests include individually fabricated hull panels, as well as secondary structural stiffener sandwich composite web panels, and stiffener flange components. The highest performing joint design is then utilized in a mock-up full-size fabrication scale structure. This structure includes both a transverse hull joint, as well as joints in the secondary structural stiffener web and flange. This mock-up fabrication scale component was then cut apart and tested in tension. The novel sandwich composite panel joint tension experimentation methods used indicate the methods studied are reliable for determination of characteristic tensile properties, and that the joints selected are effective. Investigations concerning scale effects comparing baseline fiber failure mode tension results from the coupon scale to the single panel scale, and manufacturing effects comparing joint interlaminar shear failure mode from the single panel scale to the mock-up fabrication scale, show decreased ultimate tensile strength with increased overall part size and manufacturing complexity. These factors, applied to a reference strength to achieve a nominal strength, were found to range from 0.796 to 0.846.

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Jurina, Lorenzo, Giovanni Mantegazza, and Edoardo Oliviero Radaelli. "FRCM - Strenghtening of Masonry Vaults: The “Duomo Di Colorno” and “Braidense Library” Cases in Italy." Key Engineering Materials 624 (September 2014): 494–501. http://dx.doi.org/10.4028/www.scientific.net/kem.624.494.

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In the last decade a re-discovering of the construction techniques and materials belonging to ancient buildings and heritage has grown up.Professionals and researchers have made a strong effort to understand resisting mechanisms in masonry buildings, trying to evaluate the safety factor in presence of vertical and horizontal seismic loads. As a consequence, innovative techniques and materials, as the FRCM, have been introduced to prevent local and global collapse mechanism, increasing the safety of the overall structure.The special cases of “Duomo of Colorno” and the “Braidense Library”, in Italy, are here presented.The XVIII century masonry vaults of the Duomo widely suffered due to a seismic event occurred in 2012 and a relevant crack pattern appeared.A similar situation occurred for the barrel vault of the Braidense Library due to settlement of foundations.In both cases, in order to restore the global resistance of the building, some consolidation interventions have been proposed.One of those is represented by a FRCM net applied on the upper side of the vaults. The system makes use of a carbon bi-directional fiber net inserted in an inorganic pozzolanic matrix, fully compatible with the ancient masonry support.A numerical non-linear analysis of the cathedral and of the barrel vault of the Braidense Library has demonstrated an increment up to 25% in the value of the horizontal loads that cause the formation of the first cracks, if compared with the non-consolidated situation.Furthermore, besides this passive fiber intervention, an innovative active technique called “RAM – Reinforced Arch Method” was applied on the vaults of the Duomo. The use of post-tensioned steel cables, added to the FRCM net, led to a strong increase of the horizontal collapse load.Carbon fibers are able to induce a strong increase in the resistance of the masonry under the tensile stresses caused by seismic loads, avoiding the formation of cracks or plastic hinges.Several tests have been performed on FRCM, according to Standards.In tensile and lap-tensile strength tests, the stress-strain behavior of C-FRCM control coupon specimens is bi-linear as expected. The initial branch of the curve corresponds to the un-cracked specimen, followed by a second branch with a reduced slope, corresponding to the crack specimen.The primary failure mode of the C-FRCM coupon specimens was slippage of the fibers after multiple cracking throughout the length of the specimen, perpendicular to the direction of the load, secondary de-bonding failure mode located at the tab ends was observed in some cases.Furthermore, all tensile and lap-tensile strength coupon tests passed the conditions of acceptance as per the requirements regarding environmental exposure to Freezing and Thawing, and Aging.

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Noh, Woo Ram, Young Woo Koh, Jong Hwa Hong, Xin Yang, and Kwan Soo Chung. "Failure Performance Analysis of Resistance Spot Welded Advanced High Strength Steel Sheets." Key Engineering Materials 651-653 (July 2015): 895–900. http://dx.doi.org/10.4028/www.scientific.net/kem.651-653.895.

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A numerical method to predict failure performance was developed for resistance spot welded AHSS (advanced high strength steel) sheets in this work and applied for a TRIP (transformation induced steel sheets) 980 sheet. For the numerical analysis, utilizing the numerical inverse calibration method, hardening data and fracture criteria were characterized for the base and the weld nugget based on the standard simple tension test and a newly designed miniature tension test, respectively. The characterized properties of the base and the weld nugget were then applied to analyze failure performance in the coupon tests of the lap-shear and U-shape tension tests carried out for welded sheets. The analysis was performed under the quasi-static condition in this early effort and showed reasonably good agreement with experiments both in failure modes and strength.

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Wright, Amy E., and Malcolm H. Ray. "Characterizing Guardrail Steel for LS-DYNA3D Simulations." Transportation Research Record: Journal of the Transportation Research Board 1528, no. 1 (January 1996): 138–45. http://dx.doi.org/10.1177/0361198196152800115.

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Finite-element models have three parts: geometry, connections, and material properties. As the visible parts of a model, geometry and connections are generally carefully considered. Material properties often are not chosen with the same degree of care although they are equally important to obtaining good results. Accurate simulations of vehicles striking roadside hardware require an understanding of both the material behavior and the mathematical material models in LS-DYNA3D. A method for comparing LS-DYNA3D simulations with typical ASTM materials tests is described. The behavior and modeling parameters of guardrail steel (AASHTO M-180 Class A Type II) are examined in this study. Experimental and simulation results of quasistatic coupon tests are compared for AASHTO M-180 Class A Type II guardrail steel, and parameters for guardrail steel are recommended.

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Kumar, Dr Vishal, and Ritu Rani. "Performance Evaluation of Selected Banking Stocks Listed on Bombay Stock Exchange During Pre & Post Covid-19 Crisis." International Journal of Innovation and Economic Development 7, no. 3 (August 2021): 53–61. http://dx.doi.org/10.18775/ijied.1849-7551-7020.2015.73.2005.

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Investing in the stock market has always been regarded as risky. Market sentiment is a factor that influences stock prices. The purpose of this study is to assess the performance of selected banking stocks based on risk and excess return generated by them during the study period. The study also determines the effect of certain financial variables on sample banking stocks during the time crisis of Covid’19. Economic variables such as the BSE Sensex, rate of exchange, variation in FII (Foreign Institutional Investors), and coupon rate of Government Sector (G-Sec) were analysed in conjunction with the analysis of banking stocks. The regression and correlation tests are used to determine the significance of variables using SPSS. Following the BSE’s performance provides insight into the future modifications throughout the price levels of bank shares. Following a sharp decline in the market, private sector bank stock prices are correct, but not public sector bank stock prices. Throughout the first part of the research, there is a direct relationship between the BSE, Sensex, and the selected stocks, but only a weak correlation with FII, G-Sec coupon rate, and the exchange rate. Along the second part of the research, the relationship between stock prices and economic variables varies widely between banks.

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Journal articles on the topic 'Coupon Tests'

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