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Evolution of solutions for dipolar bodies in Thermoelasticity without energy dissipation

References [1] D.S. Chandrasekharaiah, Hyperbolic Thermoelasticity: A Review of Recent Literature, Appl. Mech. Rev., 51: 705-729, 1998. [2] D.S. Chandrasekharaiah, A Note on the Uniqueness of Solution in the Linear Theory of Thermoelasticity Without Energy Dissipation, J. Elas- ticity, 43: 279-283, 1996. [3] S. Chirita, Spatial decay estimates for solutions describing harmonic vibrations in a thermoelastic cylinder, J. Thermal Stresses, 18: 421-436, 1995. [4] M. Ciarletta, A theory of micropolar

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Local Wave Energy Dissipation and Morphological Beach Characteristics along a Northernmost Segment of the Polish Coast

Morhology in Terms of Large Data Sets , Gdansk. Institute of Hydroengineering of the Polish Academy of Sciences, 1–170. Różyński G., Lin J. G. (2015) Data-Driven and Theoretical Beach Equilibrium Profiles: Implications and Consequences, Journal of Waterway, Port, Coastal, and Ocean Engineering , 141 (5). 04015002, Permalink: http://dx.doi.org/10.1061/(ASCE)WW.1943-5460.0000304 . Różyński G., Szmytkiewicz P. (2018) Some characteristic wave energy dissipation patterns along the Polish coast, Oceanologia , https:/doi.org/10.1061/j.oceano.2018

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Impact of curved shaped energy dissipaters downstream of head structures on both water energy dissipation and irrigation water quality

References Anandraj A., 2012, Investigational study on self aeration characteristic of hydraulic jump, IOSR J. Mech. Civil Eng. (IOSR-JMCE) 4(2): 27-31. Alikhani A., Behrozi-Rad R., Fathi-Moghadam M., 2010, Hydraulic jump in stilling basin with vertical end sill, Int. J. Phys. Sci. (IJPS) 5(1): 25-29. Ashour M.A, Tarek S.A., Attar S., 2014, A new water energy dissipater for efficient energy dissipation and enriching the flow with dissolved oxygen content, Limnol. Rev. 14(1):3-11. Avery S., Novak

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Modelling the Influence of Composite Stiffness on Energy Dissipation in Reinforced Composite Concrete Floors / Modelowanie Wpływu Sztywnosci Zespolenia Na Rozpraszanie Energii W Warstwie Kontaktowej Zelbetowych Stropów Zespolonych

Abstract

A continuous contact layer exists between the top and bottom layer of concrete composite reinforced floors. The contact layer is characterised by linear elasticity and frictional properties. In this paper a model of single degree of freedom of composite floor is determined. The model assumes that the restoring forces and the non-conservative internal friction forces dissipating energy are produced within the contact layer. A hysteresis loop is created in the process of static loading and unloading of the model, with the energy absorption coefficient being defined on this basis. The value of the coefficient is rising along with the growing stiffness of the composite.

A critical damping ratio is a parameter describing free decaying vibration caused by non-conservative internal friction forces in the contact layer and in the bottom and top layer. The value of the ratio in the defined model is rising along with the lowering stiffness of the element representing contact layer.

The findings resulting from the theoretical analyses carried out, including the experimental tests, are the basis for the established methods of determining the concrete layer state for reinforced concrete floors. The method is based on energy dissipation in the contact layer.

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On Discontinuties in Thermoelastic Plane Waves without Energy Dissipation Due to a Thermo-Mechanical Shock

References Chandrasekharaiah D.S. (1986): Thermoelasticity with second sound-A review. - Appl. Mech. Rev., vol.39, pp.355-376. Chandrasekharaiah D.S. (1996a): A uniqueness theorem in the theory of thermoelasticity without energy dissipation. - J. Thermal Stresses, vol.19, pp.267-272. Chandrasekharaiah D.S. (1996b): A note on the uniqueness of solution in the linear theory of thermoelasticity without energy dissipation . - J. Elasticity, vol.43, pp.279-28. Chadwick P. (1960

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Eigen Value Approach to Generalized Thermoelastic Interactions in an Unbounded Body with Circular Cylindrical Cavity without Energy Dissipation

. - Mech. Res. Commu., vol.12, No.1, pp.31-40. [5] Green A.E. and Naghdi P.M. (1991): A re-examination of the basic postulates of thermo mechanics. - Proc. Roy. Soc. London Ser. A., vol.432, pp.171-194. [6] Green A.E. and Naghdi P.M. (1992): On undamped heat waves in an elastic solid. - J. Therm. Stress., vol.15, pp.253-264. [7] Green A.E. and Naghdi P.M. (1993): Thermoelasticity without energy dissipation. - Journal of Elasticity, vol.31, No.3, pp.189-208. [8] Lahiri and Das (2008): Eigenvalue approach to

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A new water energy dissipater for efficient energy dissipation and enriching the flow with dissolved oxygen content

Abstract

One of the most important problems Egypt is facing nowadays is saving and controlling the limited available quantity of water and its quality for irrigation and other purposes. Such goals may be achieved through different types of diversion head structures across the river and in the entrance of other carrying canals. The construction of diversion head structures, which usually causes many technical problems, should have the objective of solving and overcoming to protect the structure from failure. The main problem occurs downstream. Such structures have the harmful effect of converting the potential energy gained in the upstream side to a kinetic energy in the downstream side. This energy must be dissipated shortly and safely as near as possible to the head structure to avoid its destructive effect. The hydraulic jump is the most effective tool for the dissipation of water energy, accelerating the forming of the hydraulic jump downstream such structures became essential for achieving our main goal. Using energy dissipaters on the soled apron in the downstream side of the structures was the main technique for accelerating the hydraulic jump formation and dissipating great amount of the residual harmful kinetic energy occurring downstream head structures. So early, many researchers investigated different types, shapes, and arrangements of such dissipaters to evaluate its efficiency in dissipating the water energy and accelerating the forming of the hydraulic jump. In fact, in our present study we will try to investigate some other shapes of energy dissipaters, which have not been studied enough, by evaluating its positive technical impact on: (i) percentage value of dissipating kinetic water energy; (ii) percentage value of increasing the dissolved oxygen (DO) content in the irrigation water, and improving its quality. The study is proposed to be held in the irrigation and hydraulic laboratory of the Civil department, Faculty of Engineering, Assiut University, using a movable bed tilting channel 20 m long, 30 cm wide, and 50 cm high, using fourteen types of curved dissipaters with different arrangements as shown in Table 2. It is worth mentioning that, in this first part of our paper, we will introduce a comparative analysis for the efficiency of different types of energy dissipaters available in the literature review. The most effective types of the previously studied dissipaters will be put in a comparison with our new dissipaters from the two above mentioned points of view, and the results will be presented in the second part of this paper later.

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Estimation of Stiffness and Energy Dissipation for the Models of Reinforced-Concrete Composite Slabs Based on the Investigations of Statically Loaded Slabs

composite stiffness on energy dissipation in reinforced composite concrete floors, Archives of Civil Engineering, 58, 1, 71-96, 2012. 5. A. Zbiciak, Numerical analysis of dynamic behaviour of eleastoplastic beams. Archives of Civil Engineering, 55, 3, 403-420, 2009. 6. S. Goszczyński, J. Slusarczyk, Relationship M(κ) for reinforced concrete subjected to changing loads. Archives of Civil Engineering, 55, 1, 65-78, 2009. 7. A. Halicka, A study of the stress - strain condition in the interface and support zones of composite

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Making Use of the Principle of Energy Dissipation in the Seismic Design of a Steel Structure of a Steam Boiler / Využití Principu Disipace Při Seismickém Návrhu Ocelové Konstrukce Parního Kotle

Abstract

For structural design of steel structures under seismic action there are two possible approaches of global analysis. In global analysis we can consider the structure to behave in linear elastic way or in post-elastic way with developing of plastic hinges during seismic situation. The second method is based on principle of seismic energy transformation into thermal energy. Both design methods are defined in Eurocodes but the post-elastic way is only rarely used because of design complexity. Application of this design method is presented in the entry on an example of a steam power plant boiler structure.

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Dissipation energy in viscoelastic solids under multiaxial loads

Dissipation energy in viscoelastic solids under multiaxial loads

On the basis of the three-dimensional constitutive equations for strains resulting from the Kelvin-Voigt's model and modified Hooke's law for multiaxial stress in viscoelastic solids, the formulae for the energy dissipated in a given time per unit volume have been derived. It is shown that after application or removal of triaxial static load there is no difference in the time functions governing the dissipation of strain energy of volume change and the dissipation of strain energy of distortion. Harmonic in-phase stress and harmonic out-of-phase stress as well as multiaxial periodic stress are also considered. It is demonstrated that in the process of energy dissipation due to normal and shear stress components the role of the latter is dominant.

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