Journal articles: 'Wave loading'

1

Jamieson, Wayne W., Etienne P. D. Mansard, and Geoffrey R. Mogridge. "IRREGULAR WAVE LOADING ON A CONICAL STRUCTURE." Coastal Engineering Proceedings 1, no. 21 (January 29, 1988): 167. http://dx.doi.org/10.9753/icce.v21.167.

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The horizontal forces, vertical forces and overturning moments exerted by waves on a fixed model of a 45" conical structure are presented. Irregular wave loading tests were conducted for a range of conditions described by base diameter on peak period wave length D/Lp from 0.31 to 1.76, water depth on peak period wave length h/Lp from 0.11 to 0.63, and significant wave height on peak period wave length Hm./Lp up to 0.07. Time series records, spectral densities and transfer functions for the irregular wave loading tests are used to illustrate the nonlinear nature of the measured wave loads. In most cases, similar trends in wave loading were observed for irregular and regular wave tests. For deep-water waves, the irregular and regular force measurements showed spectral peaks at the second harmonic of the wave frequency even though the waves themselves had relatively small second-order components. However, unlike the regular wave loading results, the fundamental spectral peak frequency for the irregular wave forces occurred at a frequency considerably lower than the peak frequency of the waves. Although linear diffraction theory provided a reasonable estimate of the wave forces for waves of low steepness, larger deviations were often present for higher wave steepness results. Comparison of theory and experiment for overturning moments was generally very poor for most wave conditions.

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Luo, Song, and Fengqiang Gong. "Experimental and Numerical Analyses of the Rational Loading Waveform in SHPB Test for Rock Materials." Advances in Civil Engineering 2018 (December 3, 2018): 1–13. http://dx.doi.org/10.1155/2018/3967643.

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Aiming at the determination of the rational loading waveform for rock materials, the comparative impact tests under the loadings of rectangular and half-sine stress waves were performed on red sandstone using an Ø50 mm SHPB apparatus. Experimental results with the rectangular stress wave affirm that the waveform dispersion and stress-strain curve oscillation frequently exist during the test of rock materials, which signifies that the accuracy of test results derived from the rectangular stress wave loading cannot be guaranteed. Under the loading of the half-sine stress wave, the phenomenon of wave dispersion during the tests has been eliminated radically, and there is no oscillation in the stress-strain curves. To further demonstrate the rationality of the half-sine wave loading in the SHPB test, by utilizing the three-dimensional numerical simulation approach, the propagations of rectangular, triangular, and half-sine stress waves travelling in the axial and radial directions of the SHPB with four elastic bar diameter sizes are analyzed and compared. The results show that the waveform dispersion of the rectangular and triangular stress waves always exists and will be more and more serious with increasing diameter size and propagation distance. For the half-sine stress wave, the waveform dispersion effect is very weak and not affected by the bar diameter size and propagation distance. The half-sine stress wave is the rational loading waveform for rock SHPB tests with different bar diameters.

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Foschi, Ricardo, Michael Isaacson, Norman Allyn, and Steven Yee. "Combined wave – iceberg loading on offshore structures." Canadian Journal of Civil Engineering 23, no. 5 (October 1, 1996): 1099–110. http://dx.doi.org/10.1139/l96-917.

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The Canadian Standards Association has developed and published a code for the design and construction of fixed offshore structures. This code has been subjected to a comprehensive verification process which has identified several issues warranting further study. One of these relates to the combined effects of wave and iceberg collision loading. At present, this combination is treated by the use of a load combination factor specified in the Code. The present paper describes a recent study which was undertaken to determine the appropriateness of the recommended value of the load combination factor. The study involves a numerical analysis in which loads due to waves alone, an iceberg alone, and an iceberg and waves in combination have been calculated for a range of iceberg and wave parameters. These results have been applied to a first-order reliability analysis in order to study the force levels corresponding to an annual probability of 10−4 or to the onset of global sliding with an annual probability of 10−4. The paper thereby makes recommendations for load combination factors applicable to combined wave–iceberg loading. Key words: hydrodynamics, icebergs, ocean engineering, offshore structures, wave forces, waves.

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Eslami A., Sepehr, and Marcel R. A. Van Gent. "WAVE OVERTOPPING AND RUBBLE MOUND STABILITY UNDER COMBINED LOADING OF WAVES AND CURRENT." Coastal Engineering Proceedings 1, no. 32 (January 29, 2011): 12. http://dx.doi.org/10.9753/icce.v32.structures.12.

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Coastal structures such as breakwaters are usually studied under wave loading only. However, at several locations also a current is present. For instance, breakwaters along intake and outfall channels of power plants and desalination plants, or structures in regions with important tidal currents, experience wave loading that can be affected by currents. Nevertheless, wave overtopping and rubble mound stability are usually studied under wave loading only; the effects of waves on wave overtopping and rock slope stability have been summarised in many empirical design formulae. None of the existing empirical relations account for the effects of currents on the wave loading and consequently on wave overtopping and rock slope stability. The effects of wave-current interaction on wave overtopping and rubble mound stability has not been quantified, other than that for mild currents these processes are dominated by waves. Therefore, the present study is focussed on wave loading in combination with a strong current. This study is based on physical model tests in a wave-current basin. The results show to what extent wave overtopping and rubble mound stability are affected by wave loading in combination with a current. Wave overtopping and the damage to rock slopes generally reduce due to the presence of a current compared to the situation without a current.

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Peng, Kang, Ke Gao, Jian Liu, Yujiao Liu, Zhenyu Zhang, Xiang Fan, Xuyan Yin, Yongliang Zhang, and Gun Huang. "Experimental and Numerical Evaluation of Rock Dynamic Test with Split-Hopkinson Pressure Bar." Advances in Materials Science and Engineering 2017 (2017): 1–12. http://dx.doi.org/10.1155/2017/2048591.

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Feasibility of rock dynamic properties by split-Hopkinson pressure bar (SHPB) was experimentally and numerically evaluated with ANSYS/LS-DYNA. The effects of different diameters, different loading rates, and different propagation distances on wave dispersion of input bars in SHPB with rectangle and half-sine wave loadings were analyzed. The results show that the dispersion effect on the diameter of input bar, loading rate, and propagation distance under half-sine waveform loading is ignorable compared with the rectangle wave loading. Moreover, the degrees of stress uniformity under rectangle and half-sine input wave loadings are compared in SHPB tests, and the time required for stress uniformity is calculated under different above-mentioned loadings. It is confirmed that the stress uniformity can be realized more easily using the half-sine pulse loading compared to the rectangle pulse loading, and this has significant advantages in the dynamic test of rock-like materials. Finally, the Holmquist-Johnson-Concrete constitutive model is introduced to simulate the failure mechanism and failure and fragmentation characteristics of rock under different strain rates. And the numerical results agree with that obtained from the experiment, which confirms the effectiveness of the model and the method.

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Zhang, Sheng, Xiang Hao Yang, and Xin Wen Li. "Numerical Simulation Analysis of the Effect on the One-Dimension Assumption in Different Diameter SHPB Pressure Bar by Two Kinds of Loading Waveform." Advanced Materials Research 787 (September 2013): 759–64. http://dx.doi.org/10.4028/www.scientific.net/amr.787.759.

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t is one of precondition of determining rock material dynamic parameters for one-dimension assumption of the elastic pressure bar. In order to analyze its effect by loading wave type, the dynamic stress was simulated with Ls-dynamic finite element software, when SHPB(Split Hopkinson Pressure Bar) pressure bar with diameter of 50 mm, 75 mm and 100 mm were impacted respectively by a cycle rectangular loading wave and half sine loading wave. The stress waves of cross section in different diameter pressure bar and the different distance with pressure bar end were compared and analyzed. The results indicated that the dispersion of stress waves was very serious and the matching ability of stress wave at different distances in pressure bar was poor when the rectangular wave was loaded. However, the dispersion of stress wave was not obvious with the increase of the diameter of pressure bar and the change of pressure bar when the half sine wave was loaded. The half sine loading wave which can strictly meet the one-dimension assumption is one of the ideal loading waveforms of the rocky heterogeneous materials.

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Mockutė, Agota, Enzo Marino, Claudio Lugni, and Claudio Borri. "Comparison of Nonlinear Wave-Loading Models on Rigid Cylinders in Regular Waves." Energies 12, no. 21 (October 23, 2019): 4022. http://dx.doi.org/10.3390/en12214022.

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Monopiles able to support very large offshore wind turbines are slender structures susceptible to nonlinear resonant phenomena. With the aim to better understand and model the wave-loading on these structures in very steep waves where ringing occurs and the numerical wave-loading models tend to lose validity, this study investigates the distinct influences of nonlinearities in the wave kinematics and in the hydrodynamic loading models. Six wave kinematics from linear to fully nonlinear are modelled in combination with four hydrodynamic loading models from three theories, assessing the effects of both types of nonlinearities and the wave conditions where each type has stronger influence. The main findings include that the nonlinearities in the wave kinematics have stronger influence in the intermediate water depth, while the choice of the hydrodynamic loading model has larger influence in deep water. Moreover, finite-depth FNV theory captures the loading in the widest range of wave and cylinder conditions. The areas of worst prediction by the numerical models were found to be the largest steepness and wave numbers for second harmonic, as well as the vicinity of the wave-breaking limit, especially for the third harmonic. The main cause is the non-monotonic growth of the experimental loading with increasing steepness due to flow separation, which leads to increasing numerical overpredictions since the numerical wave-loading models increase monotonically.

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Raby, Alison, Geoffrey N. Bullock, Davide Banfi, Yaqub Rafiq, and Federico Cali. "Wave loading on rock lighthouses." Proceedings of the Institution of Civil Engineers - Maritime Engineering 169, no. 1 (March 2016): 15–28. http://dx.doi.org/10.1680/jmaen.15.00002.

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Киричек, Алексей, Alexey Kirichek, Сергей Баринов, Sergey Barinov, Александр Яшин, Aleksandr Yashin, Алексей Зайцев, Aleksey Zaycev, Александр Константинов, and Aleksandr Konstantinov. "WAVE DEFORMATION MULTI-CONTACT LOADING." Bulletin of Bryansk state technical university 2017, no. 7 (December 15, 2017): 18–26. http://dx.doi.org/10.12737/article_5a337fbc06cd34.89965584.

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10

Filipot, J. F., P. Guimaraes, F. Leckler, J. Hortsmann, R. Carrasco, E. Leroy, N. Fady, et al. "La Jument lighthouse: a real-scale laboratory for the study of giant waves and their loading on marine structures." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 377, no. 2155 (August 19, 2019): 20190008. http://dx.doi.org/10.1098/rsta.2019.0008.

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This paper presents results from an experiment designed to improve the understanding of the relationship between extreme breaking waves and their mechanical loading on heritage offshore lighthouses. The experiment, conducted at La Jument, an iconic French offshore lighthouse, featured several records of wave, current and structure accelerations acquired during severe storm conditions, with individual waves as high as 24 m. Data analysis focuses on a storm event marked by a strong peak in the horizontal accelerations measured inside La Jument. Thanks to stereo-video wave measurements synchronized to the acceleration record we were able to identify and describe the breaking wave responsible for this intense loading. Our observations suggest that this giant wave (19 m high) had a crest elevation high enough to directly hit the lighthouse tower, above the substructure. This paper reveals the potential for conducting ambitious field experiments from offshore lighthouses in order to collect valuable storm waves and wave loading observations. This offers a possible second service life for these heritage structures as in situ laboratories dedicated to the study of the coastal hydrodynamics and its interaction with marine structures. This article is part of the theme issue ‘Environmental loading of heritage structures’.

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11

Lindt, John W. van de, Rakesh Gupta, Daniel T. Cox, and Jebediah S. Wilson. "Wave Impact Study on a Residential Building." Journal of Disaster Research 4, no. 6 (December 1, 2009): 419–26. http://dx.doi.org/10.20965/jdr.2009.p0419.

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Recent natural disasters around the world including both tsunamis and hurricanes, have highlighted the inability of wood buildings to withstand wave and surge loading during these extreme events. Little is known about the interaction between coastal residential light-frame wood buildings and wave and surge loading because often little is left of the buildings. This leaves minimal opportunity for forensic investigations. This paper summarizes the results of a study whose objective was to begin to better understand the interaction between North American style residential structures and wave loading. To do this, one-sixth scale residential building models typical of North American coastal construction, were subjected to tsunami wave bores generated from waves of heights varying from 10 cm to 60 cm. The lateral force produced by the wave bores were, as expected, found to vary nonlinearly with parent wave height.

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12

Ziha, Kalman. "Effects of Loading Fields on Marine Objects." Journal of Ship Production and Design 26, no. 04 (November 1, 2010): 252–64. http://dx.doi.org/10.5957/jspd.2010.26.4.252.

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This technical note evokes directionally nonuniform loading field effects on exposures of marine objects and structures in service under environmental conditions. The note firstly reveals the statistical variability of distributions of probabilities and the entropy concept of uncertainty of systems of events for identification, ordering and presentation of probabilistic seasonal nonuniformities of wind wave loading fields. This paper provides diagram of variability of wind wave directions and the chart of ocean-wide directional nonuniformities compiled from the Global Wave Statistics (GWS). It also considers seasonal loading field distributions of wind wave heights against wave directions as well as methods for calculation and presentation of directional exposabilities of marine objects and structures. The study introduces two methods for favorable placement and selection of sustainable directions of marine objects and structures exposed seasonally to nonuniform wind wave loading fields based on criteria for minimal average exposure and on robust uniform exposures during service period. The note elaborates examples of favorable placement of a marine object on six piles near the east Brazilian coast and of an oil tanker in the Gulf of Mexico. The note at the end illustrates the use of the multiple-criteria approach either to support decisions about optimal placement and sustainable headings to waves or for avoidance of unfavorable directional field effects and their combination on marine objects and structures.

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Wang, Ding, Yueliang Li, Shengwang Hao, and Dahai Zhao. "Wave-Passage Effect of Earthquake Loadings on Long Structures." International Journal of Structural Stability and Dynamics 16, no. 07 (August 3, 2016): 1550037. http://dx.doi.org/10.1142/s0219455415500376.

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The wave-passage effect of earthquake loadings on long-span structures is studied through use of a multiply-supported single-degree-of-freedom (SDOF) system excited by traveling seismic ground motions. The absolute acceleration response of the SDOF system is represented in the analytical form in the time domain. The frequency-domain analysis results indicate that the wave-passage effect may reduce the absolute acceleration response and the earthquake loading acting on the multiply-supported SDOF system. Further, for different velocities of wave-passage, the response spectra are calculated to represent the reduction of the maximum earthquake loading on the long-span system caused by the wave-passage effect. The computation results of the response spectra indicate that the reduction of the maximum earthquake loading is fluctuant, but has a general tendency to decrease with the increase in the apparent wave velocity and the structural natural period.

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van der Werf, Ivo, and Marcel van Gent. "Wave Overtopping over Coastal Structures with Oblique Wind and Swell Waves." Journal of Marine Science and Engineering 6, no. 4 (December 6, 2018): 149. http://dx.doi.org/10.3390/jmse6040149.

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Most guidelines on wave overtopping over coastal structures are based on conditions with waves from one direction only. Here, wave basin tests with oblique wave attack are presented where waves from one direction are combined with waves from another direction. This is especially important for locations where wind waves approach a coastal structure under a specific direction while swell waves approach the coastal structure under another direction. The tested structure was a dike with a smooth and impermeable 1:4 slope. The test programme consisted of four types of wave loading: (1) Wind waves only: “sea” (approaching the structure with an angle of 45°), (2) Wind waves and swell waves from the same direction (45°), (3) Wind waves and swell waves, simultaneously from two different directions (45° and −45°, thus perpendicular to each other), and (4) Wind waves, simultaneously from two different directions (45° and −45°, thus perpendicular to each other). Existing guidelines on wave overtopping have been extended to predict wave overtopping discharges under the mentioned types of wave loading (oblique sea and swell conditions).

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15

Chen, L. F., J. Zang, P. H. Taylor, L. Sun, G. C. J. Morgan, J. Grice, J. Orszaghova, and M. Tello Ruiz. "An experimental decomposition of nonlinear forces on a surface-piercing column: Stokes-type expansions of the force harmonics." Journal of Fluid Mechanics 848 (June 1, 2018): 42–77. http://dx.doi.org/10.1017/jfm.2018.339.

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Wave loading on marine structures is the major external force to be considered in the design of such structures. The accurate prediction of the nonlinear high-order components of the wave loading has been an unresolved challenging problem. In this paper, the nonlinear harmonic components of hydrodynamic forces on a bottom-mounted vertical cylinder are investigated experimentally. A large number of experiments were conducted in the Danish Hydraulic Institute shallow water wave basin on the cylinder, both on a flat bed and a sloping bed, as part of a European collaborative research project. High-quality data sets for focused wave groups have been collected for a wide range of wave conditions. The high-order harmonic force components are separated by applying the ‘phase-inversion’ method to the measured force time histories for a crest focused wave group and the same wave group inverted. This separation method is found to work well even for locally violent nearly-breaking waves formed from bidirectional wave pairs. It is also found that the $n$th-harmonic force scales with the $n$th power of the envelope of both the linear undisturbed free-surface elevation and the linear force component in both time variation and amplitude. This allows estimation of the higher-order harmonic shapes and time histories from knowledge of the linear component alone. The experiments also show that the harmonic structure of the wave loading on the cylinder is virtually unaltered by the introduction of a sloping bed, depending only on the local wave properties at the cylinder. Furthermore, our new experimental results reveal that for certain wave cases the linear loading is actually less than 40 % of the total wave loading and the high-order harmonics contribute more than 60 % of the loading. The significance of this striking new result is that it reveals the importance of high-order nonlinear wave loading on offshore structures and means that such loading should be considered in their design.

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Banfi, Davide, Alison Raby, and David Simmonds. "CHARACTERISATION OF BREAKING WAVES ON THE EDDYSTONE LIGHTHOUSE: A LABORATORY INVESTIGATION ON WAVE PRESSURE." Coastal Engineering Proceedings, no. 35 (June 23, 2017): 15. http://dx.doi.org/10.9753/icce.v35.structures.15.

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Commonly, rock lighthouses are erected on the top of steep reefs and in limited water depths. The effect of these environmental conditions on wave loading requires deeper understanding. This paper investigates wave loading at small scale for a particular case study: the Eddystone lighthouse (UK). Load characteristics due to breaking waves are obtained by the use of pressure transducers and the test program is designed to generate a comprehensive data set covering a broader range of wave conditions. Although the magnitude of wave pressures is rather random from wave to wave of the same train of regular waves, the pressure impulsivity tends to decrease with increasing relative breaking distance. Four breaker types are described and particular attention is given to time histories of the line of action of horizontal force and vertical spatial distributions. Estimation of overall forces, obtained by pressure integration, indicates that the wave loading is strongly affected by the limited water depth condition. In fact, only small plunging waves are able to break at the structure; thus, they cause small forces despite the small breaking distances. Finally, the occurrence of the breakers is investigated on a dimensionless plane given by the combination of the Iribarren number and momentum flux of Hughes.

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Raby, Alison, Geoffrey N. Bullock, Davide Banfi, Yaqub Rafiq, and Federico Cali. "Erratum: Wave loading on rock lighthouses." Proceedings of the Institution of Civil Engineers - Maritime Engineering 169, no. 3 (September 2016): 140. http://dx.doi.org/10.1680/jmaen.2016.169.3.140.

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Cha, J. Y., and M. Latheef. "Extreme wave loading on jacket structures." IOP Conference Series: Earth and Environmental Science 479 (July 14, 2020): 012037. http://dx.doi.org/10.1088/1755-1315/479/1/012037.

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Duffy, J., C. F. Shih, L. B. Freund, and R. H. Hawley. "FRACTURE INITIATION BY STRESS WAVE LOADING." Le Journal de Physique Colloques 46, no. C5 (August 1985): C5–163—C5–169. http://dx.doi.org/10.1051/jphyscol:1985521.

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Bouyssy, V., and R. Rackwitz. "Polynomial Approximation of Morison Wave Loading." Journal of Offshore Mechanics and Arctic Engineering 119, no. 1 (February 1, 1997): 30–36. http://dx.doi.org/10.1115/1.2829042.

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For offshore structures with slender elements, the modeling of random wave loads by the Morison equation yields an equation of motion which has no analytical solution for response moments except in a few limiting cases. If polynomial approximations of the Morison drag loads are introduced, some procedures are available to obtain the stationary moments of the approximate response. If the response process is fitted by non-Gaussian models such as proposed by Winterstein (1988), the first four statistical moments of the response are necessary. The paper investigates how many terms should be included in the polynomial approximation of the Morison drag loading to accurately estimate the first four response moments. It is shown that a cubic approximation of the drag loading is necessary to accurately predict the response variance for any excitation. For the fit of the first four response moments, at least a fifth-order approximation appears necessary.

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Ravichandran, G., and R. J. Clifton. "Dynamic fracture under plane wave loading." International Journal of Fracture 40, no. 3 (July 1989): 157–201. http://dx.doi.org/10.1007/bf00960599.

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Yao, Guowen, and Zhanfang Liu. "Dynamic Failure Behavior of Polycrystalline Alumina Under Impact Loading." Journal of Applied Mechanics 74, no. 5 (January 7, 2007): 990–95. http://dx.doi.org/10.1115/1.2722777.

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Plate impact experiments and impact recovery experiments were performed on 92.93wt.% aluminas using a 100mmdia compressed-gas gun. Free surface velocity histories were traced by a velocity interferometry system for any reflector (VISAR) velocity interferometer. There is a recompression signal in free surface velocity, which shows evidence of a failure wave in impacted alumina. The failure wave velocities are 1.27km∕s and 1.46km∕s at stresses of 7.54GPa and 8.56GPa, respectively. It drops to 0.21km∕s after the material released. SEM analysis of recovered samples showed the transit of intergranular microcracks to transgranular microcracks with increasing shock loading. A failure wave in impacted ceramics is a continuous fracture zone, which may be associated with the damage accumulation process during the propagation of shock waves. Then a progressive fracture model was proposed to describe the failure wave formation and propagation in shocked ceramics. The governing equation of the failure wave is characterized by inelastic bulk strain with material damage and fracture. Numerical simulation of the free surface velocity was performed in good agreement with the plate impact experiments. And the longitudinal, lateral, and shear stress histories upon the arrival of the failure wave were predicted, which present the diminished shear strength and lost spall strength in the failed layer.

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Mares-Nasarre, Patricia, and Marcel R. A. van Gent. "Oblique Wave Attack on Rubble Mound Breakwater Crest Walls of Finite Length." Water 12, no. 2 (January 28, 2020): 353. http://dx.doi.org/10.3390/w12020353.

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Rubble mound breakwaters usually present a crest wall to increase the crest freeboards without a large increase of the consumption of material. Methods in the literature to design crest walls are based on estimates of the wave loads. These methods are focused on the maximum loading that attacks a single position of the crest wall. In practice, crest walls have a finite length. Since the maximum loading does not occur at the same instant over the entire length of the crest wall for oblique waves, these methods overestimate the loading in the situation of oblique waves. Wave loads under oblique wave attack have been measured in physical model tests. A method to account for the effect of the finite length of crest walls has been developed, and design guidelines have been derived. The results of this study in combination with the existing methods in the literature to estimate the wave forces enable a more advanced design of crest walls.

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Lighthill, James. "Fundamentals concerning wave loading on offshore structures." Journal of Fluid Mechanics 173 (December 1986): 667–81. http://dx.doi.org/10.1017/s0022112086001313.

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This article is aimed at relating a certain substantial body of established material concerning wave loading on offshore structures to fundamental principles of mechanics of solids and of fluids and to important results by G. I. Taylor (1928a,b). The object is to make some key parts within a rather specialised field accessible to the general fluid-mechanics reader.The article is concerned primarily to develop the ideas which validate a separation of hydrodynamic loadings into vortex-flow forces and potential-flow forces; and to clarify, as Taylor (1928b) first did, the major role played by components of the potential-flow forces which are of the second order in the amplitude of ambient velocity fluctuations. Recent methods for calculating these forces have proved increasingly important for modes of motion of structures (such as tension-leg platforms) of very low natural frequency.

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SHIBATA, H., Y. TANABE, and S. ISHIHARA. "SIMULATION TECHNIQUE FOR ONE-DIMENSIONAL ELASTIC WAVE PROPAGATION." International Journal of Modern Physics B 22, no. 09n11 (April 30, 2008): 1564–69. http://dx.doi.org/10.1142/s0217979208047080.

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The total stress in a structure changes dynamically by the stress multiplication phenomenon in the case of a fixed boundary condition. Therefore, it is important to evaluate the reflected stress waves under an impact loading in structures. In many problems, the method of the classical position-time diagram of wave fronts is effective to analyze the maximum stress in the structure under the impact loading and for a simple arrangement of members along the axis of the one-dimensional structure. In this study, stress analyses in one-dimensional structures based on the position-time diagram of stress wave fronts were realized as a computational method with and without attenuation of stress wave. This method was applied to the problem of stress analyses in a bone under an impact loading, and the stress states were compared with the experimental results.

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Song, Jia, Chengshun Xu, and Liang Li. "The Influence of Permeability on the Propagation Characteristics of the Waves in Different Saturated Soils." Applied Sciences 11, no. 17 (September 2, 2021): 8138. http://dx.doi.org/10.3390/app11178138.

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The permeability of saturated soils has great influence on the velocities and attenuation characteristics of fast compressional wave P1, low compressional wave P2, and shear wave S in saturated soils, respectively. In three different cases, namely zero, finite, and infinite permeability, the wave equations and theoretical velocities of P1, P2, and S wave in saturated soils are given based on the u-w-p equation, respectively. According to the solutions of the wave equations, the real velocities and attenuation coefficients of three waves are redefined, respectively. In different saturated soils, the influences of the permeability and the loading frequency on the wave velocities and attenuation are discussed, respectively. Moreover, the suitable application scope of the u-p equation is discussed based on different permeabilities and loading frequencies.

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Dudko, Olga V., and Alexandr A. Mantsybora. "Shock Loading of Heteromodular Elastic Materials under Plane-Strain Condition." Key Engineering Materials 887 (May 2021): 634–39. http://dx.doi.org/10.4028/www.scientific.net/kem.887.634.

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The paper discusses the results of mathematical modeling the two-dimensional nonlinear dynamics of heteromodular elastic materials. The resistance of these materials under tension and compression is various. The deformation properties of the heteromodular medium are described within the framework of the isotropic elasticity theory with stress-dependent elastic moduli. In the plane strain case, it is shown that only two types of the nonlinear deformation waves can appear in the heteromodular elastic materials: a plane-polarized quasi-longitudinal wave and a plane-polarized quasi-transverse wave. Basing on obtained properties of the plane shock waves, two plane self-similar boundary value problems are formulated and solved.

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Raovic, Nevena, Otto Anker Nielsen, and Carlo Giacomo Prato Carlo Giacomo Prato. "DYNAMIC QUEUING TRANSMISSION MODEL FOR DYNAMIC NETWORK LOADING." Transport 32, no. 2 (July 13, 2015): 146–59. http://dx.doi.org/10.3846/16484142.2015.1062417.

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This paper presents a new macroscopic multi-class dynamic network loading model called Dynamic Queuing Transmission Model (DQTM). The model utilizes ‘good’ properties of the Dynamic Queuing Model (DQM) and the Link Transmission Model (LTM) by offering a DQM consistent with the kinematic wave theory and allowing for the representation of multiple vehicle classes, queue spillbacks and shock waves. The model assumes that a link is split into a moving part plus a queuing part, and p that traffic dynamics are given by a triangular fundamental diagram. A case-study is investigated and the DQTM is compared with single-class LTM, single-class DQM and multi-class DQM. Under the model assumptions, single-class models indicate that the LTM and the DQTM give similar results and that the shock wave property is properly included in the DQTM, while the multi-class models show substantially different travel times for two vehicle classes. Moreover, the results show that the travel time will be underestimated without considering the shock wave property.

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Lee, Ya-Jung, Chia-Hao Hsu, and Chien-Hua Huang. "Pressure Hull Analysis under Shock Loading." Shock and Vibration 15, no. 1 (2008): 19–32. http://dx.doi.org/10.1155/2008/390585.

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The hull of high performance submarines must resist underwater shock loading due to exploding torpedoes or depth bombs. An underwater shock involving an initial shock wave and successive bubble pulsating waves is so complex that a theoretical technique for deriving shock pressure distribution is required for improving simulation efficiency. Complete shock loading is obtained theoretically in this work, and responses of a submarine pressure hull are calculated using ABAQUS USA (Underwater Shock Analysis) codes. In the long run, this deflection and stress data will assist in examining the structural arrangement of the submarine pressure hull.

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Myra, J. R., D. A. D’Ippolito, D. W. Forslund, and J. U. Brackbill. "Sheath-plasma waves and anomalous loading in ion-Bernstein-wave experiments." Physical Review Letters 66, no. 9 (March 4, 1991): 1173–76. http://dx.doi.org/10.1103/physrevlett.66.1173.

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31

Banerjee, Arundhuti, Tanusree Chakraborty, and Vasant Matsagar. "Stochastic Dynamic Analysis of an Offshore Wind Turbine Considering Frequency-Dependent Soil–Structure Interaction Parameters." International Journal of Structural Stability and Dynamics 18, no. 06 (June 2018): 1850086. http://dx.doi.org/10.1142/s0219455418500864.

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This study investigates the dynamic response of a 5[Formula: see text]MW offshore wind turbine with monopile foundation subjected to wind and wave actions under parked condition. It includes dynamic interaction between the monopile and the underlying soil subjected to stochastic wind and wave loading. The offshore wind turbine tower has been modeled using the finite element software ANSYS 14 as a line structure and it comprises a rotor blade system, a nacelle, and a flexible tower under parked condition. The mass of the rotor, blade, and nacelle are lumped at the top of the tower for simplicity. Stochastic wind and wave loadings are simulated using the Kaimal spectrum and the Pierson–Moskowitz spectrum correlating wind and wave forces, respectively. The soil–structure interaction (SSI) effect at the foundation level is taken into consideration by including rotational as well as lateral spring constants derived from Wolf’s double cone model for embedded foundations. The results are studied in the frequency domain for both wind and wave loadings in the form of power spectral density functions, which show that the response of the structure depends not only on the external forces but also on the soil–structure interaction effect. Under very soft soil conditions, the displacement response is amplified to a very high value under wind loading when compared with that under wave loading at lower frequencies. Incorporation of soil–structure interaction also modified the peak value of displacement and its subsequent frequency when compared with that for the fixed base structure which does not consider soil–structure interaction.

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32

Leng, Dingxin, Haiyan Xiao, Lei Sun, Guijie Liu, Xiaojie Wang, and Lingyu Sun. "Study on a magnetorheological elastomer-base device for offshore platform vibration control." Journal of Intelligent Material Systems and Structures 30, no. 2 (November 14, 2018): 243–55. http://dx.doi.org/10.1177/1045389x18808398.

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Wave loading is one of the leading factors contributing to fatigue damage of offshore platforms. Vibrations in marine platforms due to nonlinear hydrodynamic forces can reduce platform productivity, endanger safety, and affect serviceability. This article presents numerical evaluation of a magnetorheological elastomer device for wave-induced vibration reduction of offshore platform. Random wave loadings are estimated by wave spectrum analysis and Morison’s equations. By altering field-induced stiffness of magnetorheological elastomers and non-resonance control strategy, the wave-induced vibration of offshore platform is effectively reduced, and the magnetorheological elastomer device presents strong control robustness under various wave loadings. This work indicates that magnetorheological elastomer-base device may open a new insight for vibration mitigation of ocean structures.

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33

Maevskii, K. K. "Shock-wave loading of elconites: Numerical investigation." Journal of Physics: Conference Series 1709 (December 2020): 012004. http://dx.doi.org/10.1088/1742-6596/1709/1/012004.

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Hu, Sau‐Lon James, George Tsiatas, and James E. McGrath. "Optimal Linearization of Morison‐Type Wave Loading." Journal of Engineering Mechanics 117, no. 7 (July 1991): 1537–53. http://dx.doi.org/10.1061/(asce)0733-9399(1991)117:7(1537).

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35

Wolters, Guido, Marcel Van Gent, Jelle Olthof, and Gregory Smith. "SLOPED GRANULAR OPEN FILTERS UNDER WAVE LOADING." Coastal Engineering Proceedings 1, no. 34 (October 26, 2014): 23. http://dx.doi.org/10.9753/icce.v34.structures.23.

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36

Novikov, S. A. "Strength with quasistatic and shock-wave loading." Combustion, Explosion, and Shock Waves 21, no. 6 (November 1985): 722–29. http://dx.doi.org/10.1007/bf01463679.

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37

Gizhevskii, B. A., V. R. Galakhov, and E. A. Kozlov. "Effects of shock-wave loading in oxides." Petrology 20, no. 4 (July 2012): 317–30. http://dx.doi.org/10.1134/s0869591112040042.

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38

Alagan Chella, Mayilvahanan, Andrew B. Kennedy, and Joannes J. Westerink. "Wave Runup Loading Behind a Semipermeable Obstacle." Journal of Waterway, Port, Coastal, and Ocean Engineering 146, no. 4 (July 2020): 04020014. http://dx.doi.org/10.1061/(asce)ww.1943-5460.0000569.

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39

White, R. M., and S. W. Wenzel. "Fluid loading of a Lamb‐wave sensor." Applied Physics Letters 52, no. 20 (May 16, 1988): 1653–55. http://dx.doi.org/10.1063/1.99047.

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40

Chan, H. Y., and R. E. Melchers. "Wave loading effect in offshore structural reliability." Structural Safety 7, no. 1 (January 1990): 1–10. http://dx.doi.org/10.1016/0167-4730(90)90009-e.

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Pitchforth, D. J., T. J. Rogers, U. T. Tygesen, and E. J. Cross. "Grey-box models for wave loading prediction." Mechanical Systems and Signal Processing 159 (October 2021): 107741. http://dx.doi.org/10.1016/j.ymssp.2021.107741.

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42

Xu, Jicheng, and Xibing Li. "The dynamical loading on rock with different loading wave shapes conventional SHPB." Journal of Central South University of Technology 5, no. 1 (May 1998): 57–59. http://dx.doi.org/10.1007/s11771-998-0035-6.

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43

Li, Qingwen, Lan Qiao, Gautam Dasgupta, Siwei Ma, Liping Wang, and Jianghui Dong. "Blasting Vibration Safety Criterion Analysis with Equivalent Elastic Boundary: Based on Accurate Loading Model." Shock and Vibration 2015 (2015): 1–10. http://dx.doi.org/10.1155/2015/604683.

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In the tunnel and underground space engineering, the blasting wave will attenuate from shock wave to stress wave to elastic seismic wave in the host rock. Also, the host rock will form crushed zone, fractured zone, and elastic seismic zone under the blasting loading and waves. In this paper, an accurate mathematical dynamic loading model was built. And the crushed zone as well as fractured zone was considered as the blasting vibration source thus deducting the partial energy for cutting host rock. So this complicated dynamic problem of segmented differential blasting was regarded as an equivalent elastic boundary problem by taking advantage of Saint-Venant’s Theorem. At last, a 3D model in finite element software FLAC3D accepted the constitutive parameters, uniformly distributed mutative loading, and the cylindrical attenuation law to predict the velocity curves and effective tensile curves for calculating safety criterion formulas of surrounding rock and tunnel liner after verifying well with the in situ monitoring data.

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Igra, O., X. Wu, G. Q. Hu, and J. Falcovitz. "Shock Wave Propagation Into a Dust-Gas Suspension Inside a Double-Bend Conduit." Journal of Fluids Engineering 124, no. 2 (May 28, 2002): 483–91. http://dx.doi.org/10.1115/1.1466457.

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Using conduits in which a transmitted shock wave experiences abrupt changes in its direction of propagation is an effective means for shock wave attenuation. An additional attenuation of the transmitted shock wave is obtained when the medium contained inside the conduit (through which the shock wave is transmitted) is a suspension rather than a pure gas. The present numerical study shows that adding small solid particles (dust) into the gaseous phase results in sharp attenuation of all shock waves passing through the conduit. It is shown that the smaller the dust particles diameter is, the higher the shock attenuation becomes. Increasing the dust mass loading in the suspension also causes a quick attenuation. By proper choice of dust mass loading in the suspension, or the particles diameter, it is possible to ensure that the emerging wave from the conduit exit channel is a (smooth) compression wave, rather than a shock wave.

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45

Raby, A. C., A. Antonini, A. Pappas, D. T. Dassanayake, J. M. W. Brownjohn, and D. D'Ayala. "Wolf Rock lighthouse: past developments and future survivability under wave loading." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 377, no. 2155 (August 19, 2019): 20190027. http://dx.doi.org/10.1098/rsta.2019.0027.

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Lighthouses situated on exposed rocky outcrops warn mariners of the dangers that lurk beneath the waves. They were first constructed when approaches to wave loading and structural response were relatively unsophisticated, essentially learning from previous failures. Here, we chart the evolution of lighthouses on the Wolf Rock, situated between Land's End and the Isles of Scilly in the UK. The first empirical approaches are described, followed by design aspects of the present tower, informed by innovations developed on other rocky outcrops. We focus on a particular development associated with the automation of lighthouses: the helideck platform. The design concept is described and the structure then scrutinized for future survivability, using the latest structural modelling techniques of the entire lighthouse and helideck. Model validation data were obtained through a complex logistical field operation and experimental modal analysis. Extreme wave loading for the model required the identification of the 250-year return period wave using a Bayesian method with informative prior distributions, for two different scenarios (2017 and 2067). The structural models predict responses of the helideck to wave loading which is characterized by differential displacements of 0.093 m (2017) and 0.115 m (2067) with associated high tension forces and plastic strain. This article is part of the theme issue ‘Environmental loading of heritage structures’.

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Tyupanova, Olga, Sergey Nadezhin, Pavel Duday, and Andrey Ivanovsky. "Numerical analysis of damage kinetics in aluminium under axisymmetric loading." EPJ Web of Conferences 183 (2018): 01066. http://dx.doi.org/10.1051/epjconf/201818301066.

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Based on the analysis of the results of two R-Damage experiments, this paper provides a variant of a relation to simulate the spall damage recollection under the effect of weak compression waves. This relation closes the kinetic fracture model, considering both growth and recollection of damage. Using this model makes it possible to simulate adequately (with good quantitative agreement) the sequence of the processes “shock-wave compression – spall fracture – convergence of spall layer – recollection of damaged medium”, including the dynamics of the compacting wave arrival to the internal surface of the hollow cylindrical targets since it passed through the damaged media.

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Lee, Jong-Sub, Geunwoo Park, Yong-Hoon Byun, and Changho Lee. "Modified Fixed Wall Oedometer When Considering Stress Dependence of Elastic Wave Velocities." Sensors 20, no. 21 (November 5, 2020): 6291. http://dx.doi.org/10.3390/s20216291.

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A modified oedometer cell for measuring the applied stresses and elastic waves at the top and bottom of the specimen is developed to evaluate the effect of the side friction on the stress dependence of the elastic wave velocities. In the modified cell, two load cells are installed at the top and bottom plates, respectively. To generate and detect the compressional and shear waves, a pair of piezo disk elements and a pair of bender elements are mounted at both the top and bottom plates. Experimental results show that the stresses measured at the bottom are smaller than those measured at the top during the loading and vice versa during unloading, regardless of the densities and heights of the specimens. Under nearly saturated conditions, the compressional wave velocities remain almost constant for the entire stress state. With plotting stresses measured at top, the shear wave velocities during unloading are greater than those during loading, whereas with plotting stresses measured at bottom, the shear wave velocities during unloading are smaller than those during loading owing to the side friction. The vertical effective stress may be simply determined from the average values of the stresses measured at the top and bottom of the specimens.

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48

Van Heteren, J., H. C. Botma, A. P. Roskam, and J. A. Battjes. "VERIFICATION OF THE CONSEQUENCES OF WAVEDIRECTIONALITY ON THE LOADING OF LONG COASTAL STRUCTURES BY FIELD EXPERIMENTS." Coastal Engineering Proceedings 1, no. 20 (January 29, 1986): 179. http://dx.doi.org/10.9753/icce.v20.179.

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Field measurements were done at the Haringvliet barrier to verify the theory that loading on long structures shows a considerable reduction if wave directionality is taken into account instead of calculating with uniform long crested waves. Wave loads were measured with a row of pressure meters at the barrier. Directional parameters of the incoming wave field were calculated from the signals of a 3-component acoustic current meter, mounted 7.5 meter in front of the barrier. These calculations were different from those used for an open sea, since the waves near a reflecting structure are formed by two highly correlated wave fields. The agreement between the results of the measurements and theory is good.

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Mukhlas, Nurul 'Azizah, Noor Irza Mohd Zaki, Mohd Khairi Abu Husain, and Gholamhossein Najafian. "Comparison of Extreme Surface Elevation for Linear and Nonlinear Random Wave Theory for Offshore Structures." MATEC Web of Conferences 203 (2018): 01021. http://dx.doi.org/10.1051/matecconf/201820301021.

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For offshore structural design, the load due to wind-generated random waves is usually the most important source of loading. While these structures can be designed by exposing them to extreme regular waves (100-year design wave), it is much more satisfactory to use a probabilistic approach to account for the inherent randomness of the wave loading. This method allows the statistical properties of the loads and structural responses to be determined, which is essential for the risk-based assessment of these structures. It has been recognized that the simplest wave generation is by using linear random wave theory. However, there is some limitation on its application as some of the nonlinearities cannot be explained when higher order terms are excluded and lead to underestimating of 100-year wave height. In this paper, the contribution of nonlinearities based on the second order wave theory was considered and being tested at a variety of sea state condition from low, moderate to high. Hence, it was proven that the contribution of nonlinearities gives significant impact the prediction of 100-year wave's design as it provides a higher prediction compared to linear wave theory.

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Ahmad, Sayyid Zainal Abidin Syed, Mohd Khairi Abu Husain, Noor Irza Mohd Zaki, Mohd Hairil Mohd, and Gholamhossein Najafian. "Comparison of Various Spectral Models for the Prediction of the 100-Year Design Wave Height." MATEC Web of Conferences 203 (2018): 01020. http://dx.doi.org/10.1051/matecconf/201820301020.

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Offshore structures are exposed to random wave loading in the ocean environment, and hence the probability distribution of the extreme values of their response to wave loading is required for their safe and economical design. In most cases, the dominant load on offshore structures is due to wind-generated random waves where the ocean surface elevation is defined using appropriate ocean wave energy spectra. Several spectral models have been proposed to describe a particular sea state that is used in the design of offshore structures. These models are derived from analysis of observed ocean waves and are thus empirical in nature. The spectral models popular in the offshore industry include Pierson-Moskowitz spectrum and JONSWAP spectrum. While the offshore industry recognizes that different methods of simulating ocean surface elevation lead to different estimation of design wave height, no systematic investigation has been conducted. Hence, the aim of this study is to investigate the effects of predicting the 100-year responses from various wave spectrum models. In this paper, the Monte Carlo time simulation (MCTS) procedure has been used to compare the magnitude of the 100-year extreme responses derived from different spectral models. Additionally, the linear random wave theory (LRWT) was implemented to simulate the offshore structural responses due to random wave loading. The models have been tested for three different environmental conditions represented by Hs = 15m, 10m and 5m respectively. The accuracy of the predictions of the 100-year responses from Pierson-Moskowitz and JONSWAP spectrums will then be investigated.

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Journal articles on the topic 'Wave loading'

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