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Mechanical and Vibration Properties of Self-compacting Rubberized Concrete Beams with Silica Fume Enhancement

Iranian Journal of Science and Technology - Transactions of Civil Engineering 2024年 1-13页

作者： Banaei, Ali Asadi, Payam Eftekhar, Mohammad Reza Department of Civil Engineering Isfahan University of Technology Isfahan 84156-83111 Iran

Incorporating rubber into concrete aligns with sustainable development goals, making the mechanical evaluation of structural rubber concrete beams crucial for design purposes and assessing the seismic vulnerability of rubberized concrete structures. This study focuses on the experimental evaluation of the mechanical behavior of self-compacting concrete beams containing rubber particles and assesses the effects of silica fume to counterbalance the reduced strength of rubberized concrete. The experiments determined the load-deformation curve, load capacity, crack patterns and propagation, frequency, and damping ratio of the beams. The results indicate that while the compressive and tensile strengths of the beams can decrease by up to 70% due to the incorporation of rubber particles, the addition of silica fume significantly enhances these strengths by up to 60% and 66%, respectively. Although rubber particles reduce the ultimate load-bearing capacity of the beams, they help limit crack depth and increase the number of cracks along the beam's length. As a result, the inclusion of rubber particles improves the inherent damping ratio and displacement ductility of the beams. The frequency of the beams decreases by up to 10%, while their damping ratio increases by as much as 2.7 times with the incorporation of rubber particles. © The Author(s), under exclusive licence to Shiraz University 2024.

关键词： Ductility index image processing technique Mechanical properties Modal analysis Rubber concrete beams Self-compacting concrete

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Three phase mesoscopic concrete model based on real inner structure of concrete sample

Three phase mesoscopic concrete model based on real inner st...

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International Conference on Heterogeneous Material Mechanics (ICHMM)

作者： Wu, X. Li, J. Tongji Univ Dept Bldg Engn Shanghai 20092 Peoples R China

ISBN: (纸本)9781932078800

From a mesoscopic point of view, concrete are heterogeneous materials which be defined as a combination of at least two chemically and mechanically distinct materials with a definite interface separating the components. It is hard to deny the significant chemically and mechanically differences among the aggregate, mortar and interface transition zone (ITZ). The photos of sample section are full of this useful information, for example, including the space distribution of aggregates, the shape of aggregates, the areas of aggregates and so on. This information seldom can be caught by the generally random model which is generated through algorithms. Nowadays the quick development of image processing techniques enhances researcher's ability to deal with real digital images of concrete samples section. Based on this image, different material parameters represents aggregate, mortar and interfacial transition zone (ITZ) are related to finite elements individually, so digital image-based finite element (FE) model is build. With the help of digital image-based FE model, the results of numerical simulation can be compared with the real ones.

关键词： image processing technique finite element method numerical simulation

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Automatic detection of sand ripple features in sidescan sonar imagery

Automatic detection of sand ripple features in sidescan sona...

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Oceans Conference

作者： Crawford, Anna Skarke, Adam Def Res & Dev Canada Atlantic Res Ctr Dartmouth NS Canada Mississippi State Univ Dept Geosci Mississippi State MS 39762 USA

ISBN: (纸本)9781479949182

A novel image processing technique, based on fingerprint analysis, is applied to sidescan sonar data in order to automatically extract seabed ripple orientation, wavelength, and defect density parameters. The technique is applied to seabed imagery collected on repeat passes over the same ripple field at headings distributed over 360 degrees in order to evaluate ripple parameter extraction across a range of relative angles between the sonar and dominant ripple orientation. The presence of ripples increases the difficulty of identifying objects of interest in sidescan sonar seabed imagery. The potential for utilizing the density of ripple defects as an objective parameter for the quantification of this difficulty in the context of object detection operations is discussed. Results suggest a number of sidescan sonar data analysis applications that are highly compatible with unsupervised detectors and autonomous mission planning processes.

关键词： data analysis geophysical image processing object detection oceanographic techniques sand sonar imaging autonomous mission planning processes defect density parameters dominant ripple orientation fingerprint analysis image processing technique object detection operations objective parameter relative angles repeat passes ripple defects ripple field ripple parameter extraction sand ripple features seabed ripple orientation sidescan sonar data sidescan sonar data analysis applications sidescan sonar seabed imagery unsupervised detectors Algorithm design and analysis Backscatter Bifurcation image edge detection Sonar detection Standards

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A small scale experiment for multi-modal VIV response of a long flexible horizontal cylinder

A small scale experiment for multi-modal VIV response of a l...

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17th International Offshore and Polar Engineering Conference (ISOPE 2007)

作者： Prastianto, Rudi Walujo Otsuka, Koji Ikeda, Yoshiho Osaka Prefecture Univ Dept Marine Syst Engn Sakai Osaka Japan

ISBN: (纸本)9781880653685

Vibration response of a long flexible horizontal cylinder having pretension in water flow is very complex. Some phenomena which were still not clearly understood have been found in its motion behavior. This paper presents experimental results of a long flexible horizontal cylinder have been towed in still water which is free to respond in both, in-line and transverse directions. The length-to-diameter ratio of the test model was around 269 with a mass ratio of 1.7. Reynolds number varied from 9 x 10(2) up to 4.5 x 10(3). The model was positioned in two angles of 0 and 5 degree in horizontal plane which respect to the fluid flow. Pretension was applied to the test cylinder for towing speed of 0.1 up to 0.5 m/s in each case of the test. The motion data were recorded as digital image data using some CCD cameras and were analyzed using image processing technique. The frequencies of the CF (cross-flow) VIV response follow the Strouhal frequencies for a constant Strouhal number (St = 0. 166) for both cylinder position, theta = 0 and theta = 5 degree respectively. It was found that multi-mode responses occurred at higher flow velocities. Further analysis will be done and additional results will be published later.

关键词： long flexible cylinder in-line and cross-flow motion multi-modal vortex-induced vibration (VIV) response image processing technique

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Physical properties and mathematical modeling of melon (Cucumis melo L.) seeds and kernels

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Journal of the Saudi Society of Agricultural Sciences 2017年第3期16卷 218-226页

作者： Mansouri, Ali Mirzabe, Amir Hossein Ráufi, Ahmad Department of Agrotechnology University of Tehran College of Abouraihan Tehran Iran Department of Horticultural Science University of Tehran College of Abouraihan Tehran Iran

In the present research, some physical properties of Somsori and Varamin varieties of melon seeds and kernels were studied;three principal dimensions (length, width and thickness) of melon seeds and kernels were measured using image processing technique. Results indicated that mass of the Somsori and Varamin varieties seeds was equal to 0.043 and 0.052 g, respectively. The corresponding value for melon kernels was found to be 0.031 and 0.036, respectively. True density of the Somsori and Varamin varieties seeds was equal to 1182.612 and 1132.058 kg m⁻³, respectively. The corresponding value for melon kernels was found to be 1479.731 and 1535.911 kg m⁻³, respectively. Results showed that with increasing volume of container from 500 mL to 600 mL bulk density of the seeds increased. But with increasing volume of container from 600 mL to 1500 mL, bulk density of the seeds decreased. Also with increasing volume of container from 500 mL to 1000 mL bulk density of the kernels increased. But with increasing volume of container from 1000 mL to 1500 mL, bulk density of the kernels decreased. Values of coefficient of friction of seeds and kernels on rubber surface were more than the iron, galvanized and plywood surfaces, but values of coefficient of friction of seeds and kernels on galvanized surface were less the other surfaces. Comparison between three methods of measuring angle of repose showed that values based on pouring method and filling method were more and less than the other methods, respectively. © 2015 The Authors

关键词： Angle of repose Dimensional properties Frictional properties Gravimetric properties image processing technique

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High quality image reconstruction with self-pumped phase conjugation

High quality image reconstruction with self-pumped phase con...

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Photonics Asia Symposium 2002

作者： Miyakawa, K Ichinose, M Yamashita, M Topcon Corp R&D Ctr Tokyo 1748580 Japan

ISBN: (纸本)0819447080

Improvement of quality on reconstructed self-pumped phase conjugate images has been investigated. Since self-pumped phase conjugate beams generally fluctuate as a function of irradiation time, spatial and temporal changes of their fluctuations make the quality of images lower. It is necessary to study elimination of these fluctuations from phase conjugate beams for reconstruction of high quality images. However, it will be expected that this condition be decided by the intensity distribution of incident beam. In our experiments, transparent samples which consist of some thick layers were irradiated by cw argon ion laser(wavelength: 514.5nm), and recorded phase conjugate and input images were analyzed using image processing technique as a function of irradiation time. As a result, it was obvious that phase conjugate images from volume sample were stable. Finally, imaging of transparent object was studied from point of view of some thick layers and their application to optical measurements using self-pumped phase conjugate mirror were discussed.

关键词： phase conjugate image fluctuation high quality image processing technique thick layer optical measurement

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The characterisation of a cerenkov imaging telescope for ground-based gamma-ray astronomy through correlation of coincident images

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Experimental Astronomy 1993年第2期4卷 77-86页

作者： Kornienko, A.P. Stepanian, A.A. Zyskin, Yu.L. Neshpor, Yu.I. Fomin, V.P. Shytov, V.G. Vladimirsky, B.M. Crimean Astrophysioal Observatory p/o Nauchny Crimea 334413 Ukraine

The Cerenkov installation of the Crimean Astrophysical Observatory, consisting of two identical detectors, separated by 20m, are mounted in parallel for comparing the parameters of images. The average counting rate at one section is 35% higher than at the other. The number of coincident flashes make up 55% for one section and 76% for the second section. The comparison of parameters of coincident events shows high correlation of centroid positions (correlation coefficient r=0.98), of length (r=0.70), orientational angle (r=0.64). The correlation of width parameters is considerably lower (r=0.44). Since the coincident flashes at the two sections correspond to the same EAS their image parameters must be the same or very close. Hence the correlation coefficient between identical parameters of coincident flashes will characterize the quality of equipment and the method of observational data processing. © 1993 Kluwer Academic Publishers.

关键词： image processing technique VHE gamma-ray

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Contrast enhancement of landsat data on multispectral data analysis system

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Journal of the Indian Society of Photo-Interpretation and Remote Sensing 1980年第2期8卷 27-32页

作者： Rao, T.Ch. Malleswara Venkataratnam, L. Rao, K.R. National Remote Sensing Agency Secunderabad India

Contrast enhancement, one of the image processing techiques, is developed on the Multispectral Data Analysis System (MDAS) for enhancing the LANDSAT data. The purpose of image processing for enhancement is to improve the obscure objects data in the image to stand out more readily for good sensing to the human eye. It is observed on MDAS that some of the LANDSAT scenes when examined on the color display, give inadequate information for the required objective of interpretation. This is due to poor tonal contrast in the scene because of prevailing climatological conditions at the time of satellite pass over that area. Also, the LANDSAT data usually occupy a small subset of the total brightness range 0-127. To provide optimal contrast and variation for color compositing, contrast enhancement may by performed on the data before going to trie information processing (categolization) on the landsat scene. This paper describes the algorithms of parametric linear and non linear contrast enhancement techniques. A typical example to differentiate the degree of salinity in the soils was tested with the suggested algorithms and the results are tabulated in the form of photographs. The test area is selected from Haryana (frame no. 158-040 dated 2nd May, 1977) for testing the algorithms. The enhancement software developed on the MDAS stretches all the four Landsat bands and generates an output tape with the format similar to LANDSAT computer compatible tape (CCT). The stretched results of 5 and 7 bands are displayed in this paper. A false color composite which appears as on the color displya could also be generated from 4, 5 and 7 bands. The enhanced output was found to be useful for easily categorizing the data into various categories on MDAS. © 1980 Springer-Verlag.

关键词： Contrast Enhancement Landsat image processing technique LANDSAT Data Color Composite

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Determination of volumetric shrinkage of an expansive soil using digital camera images

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INTERNATIONAL JOURNAL OF GEOTECHNICAL ENGINEERING 2021年第5期15卷 624-632页

作者： Julina, M. Thyagaraj, T. Indian Inst Technol Dept Civil Engn Madras Tamil Nadu India

The volume change during drying of compacted expansive soils occurs in the form of reduction in overall volume and development of cracks. Accurate determination of volume of shrunken soil specimens becomes essential to understand the shrinkage behaviour of compacted expansive soils. Mercury displacement method available for the bulk volume measurement of cylindrical small samples suffers from the serious limitations such as the restrictions of using the mercury as it is a hazardous material and the size of specimens is limited to small samples/portions. In the past few years, the digital camera images have been successfully utilised in studying the crack pattern and various parameters associated with reconstituted soils dried from slurry state. Fewer works have been carried out to quantify the cracks in the compacted soils, especially in compacted expansive soils. In this paper, simple methods for the determination of the volume of shrunken soil specimens excluding the volume of cracks are proposed based on the digital camera images captured on thin oedometer shrunken soil specimen along with the vernier calliper method. The results were compared with the mercury displacement method. Cracks which extended from top to bottom of the shrunken specimen during drying assisted in employing these methods. The effect of cracks on shrinkage deformations during second drying cycle and at the end of five drying cycles under a vertical stress of 12.5 kPa was studied.

关键词： Expansive soil shrinkage cracks digital camera image image processing technique

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Computerized assessment of developmental changes in the mastoid air cell system

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International Congress Series 2003年第C期1254卷 487-491页

作者： Isono, Michio Ito, Akihiko Nakayama, Kazuko Miyashita, Hiroaki Saito, Kei Murata, Kiyotaka Department of Otolaryngology Kinki University School of Medicine 377-2 Ohno-Higashi Osakasayama Osaka Japan

Background: We have developed a technique for direct volume measurement based on high-resolution CT. This report will describe our findings on the measurement of the mastoid air cell system of infants, and its developmental changes with age. Methods: The study covered 43 males and 37 females, aged 1-18 years. The temporal bone was imaged by slicing at 2 mm thickness through the high-resolution CT, so that the entire air cell system was included, and the resultant data were analyzed by the image processing technique. Results: It was confirmed that the mastoid air volume increased with age. By 9-10 years old, it had reached about 80% of the volume of an adult, and at 14-15 years old, it had reached the mean adult value. Conclusion: Our technique, based on CT image, proved to be much more useful because of the higher accuracy and capability of three-dimensional assessment. The detailed analysis described here could have been obtained only through the postmortem histological study. Our method is of high significance because it allows assessing the antemortem developmental changes in infants. © 2003 British Association for Paediatric Otorhinolaryngology (BAPO). All rights reserved.

关键词： High-resolution CT image processing technique Mastoid air cell system Mastoid air volume Three-dimensional-CT

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