• Structural Engineering and Mechanics
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• v.65 no.5
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• pp.505-511
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• 2018

Recently, a new foundation model called "Dynamic foundation model" was proposed for the dynamic analysis of structures on the foundation. This model includes a linear elastic spring, shear layer, viscous damping and the special effects of mass density parameter of foundation during vibration. However, the relationship of foundation property parameters with the experimental parameter of the influence of foundation mass also has not been established in previous research. Hence, the purpose of the paper presents a simple experimental model in order to establish relationships between foundation properties such as stiffness, depth of foundation and experimental parameter of the influence of foundation mass. The simple experimental model is described by a steel plate connected with solid rubber layer as a single degree of freedom system including an elastic spring connected with lumped mass. Based on natural circular frequencies of the experimental models determined from FFT analysis plots of the time history of acceleration data, the experimental parameter of the influence of foundation mass is obtained and the above relationships are also discussed.

• Coupled systems mechanics
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• v.12 no.1
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• pp.83-102
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• 2023

First introduced in 2016, the dynamic foundation model is an interesting topic in which the foundation is described close to reality by taking into account the influence of the foundation mass in the calculation of oscillation and is an important parameter that should be considered. In this paper, a follow-up investigation is conducted with the object of the Mindlin plate on a nonlinear dynamic foundation under moving loads. The base model includes nonlinear elastic springs, linear Pasternak parameters, viscous damping, and foundation mass. The problem is formulated by the finite element analysis and solved by the Newmark-β method. The displacement results at the center of the plate are analyzed and discussed with the change of various parameters including the nonlinear stiffness, the foundation mass, and the load velocity. The dynamic response of the plate sufficiently depends on the foundation mass.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.711-714
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• 2005

This paper is for the vibration analysis of thick plate with concentrated mass on a inhomogeneous pasternak foundation. the thick rectangular plate resting on a inhomogeneous pasternak foundation is isotropic, homogeneous and composite with linearly elastic material. In order to analyize plat which is supported on inhomogeneous pasternak foundation, the value of winkler foundation parameter(WFP) of centural and border zone of plate are chosen as Kw1 and Kw2 respectively. The value of Kw1 and Kw2 can be changed as 0, 10, $10^2,\;10^3$ and the value of SFP(shear foundation parameter) also be changed 0, 5, 10, 15 respectively. Finally, In this paper, vibration of retangular plate on the inhomogeneous pasternak foundation, natural frequency of this plate with Concentrated Mass are calculated

• Geomechanics and Engineering
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• v.34 no.6
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• pp.649-664
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• 2023

Structural inertial interaction is a representative the effect of dynamic soil-foundation-structure interaction (SFSI), which leads to a relative displacement between soil and foundation, period lengthening, and damping increasing phenomena. However, for a system with a significantly heavy foundation, the dynamic inertia of the foundation influences and interacts with the structural seismic response. The structure-to-foundation mass ratio (MR) quantifies the distribution of mass between the structure and foundation for a structure on a shallow foundation. Although both systems exhibit the same vertical factor of safety (FS_v), the MR and corresponding seismic responses attributed to the structure and foundation masses may differ. This study explored the influence of MR on the permanent deformation and seismic response of soil-foundation-structure system considering SFSI via numerical simulations. Given that numerous dimensionless parameters of SFSI described its influence on the structural seismic response, the parameters, except for MR and FS_v, were fixed for the sensitivity analysis. The results demonstrated that the foundation inertia of heavier foundations induced more settlement due to sliding behavior of heavily-loaded systems. Moreover, the structural inertia of heavier structures evidently exhibited foundation rocking behavior, which results in a more elongated natural period of the structure for lightly-loaded systems.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.05a
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• pp.805-809
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• 2004

This paper is for the vibration analysis of thick plate with concentrated mass on a inhomogeneous pasternak foundation. The vibration of rectangular plate on the inhomogeneous pasternak foundation, natural frequency of this plate with Concentrated Mass are calculated A thick rectangular plate resting on a inhomogeneous pasternak foundation is isotropic, homogeneous and composite with linearly elastic material. In order to analysis plate which is supported on inhomogeneous pasternak foundation, the value of winkler foundation parameter(WFP) of centural and border zone of plate are chosen as WFP1 and WFP2 respectively. The value of WFP1 and WFP2 can be changed as 10, 10$^3$ and the value of SFP(shear foundation parameter) also be changed 5, 15 respectively.

• Structural Engineering and Mechanics
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• v.59 no.6
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• pp.1019-1035
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• 2016

This paper proposes a new foundation model called "Dynamic foundation model" for the dynamic analysis of plates on foundation subjected to a moving oscillator. This model includes a linear elastic spring, shear layer, viscous damping and the special effects of mass density parameters of foundation during vibration. By using finite element method and the principle of dynamic balance, the governing equation of motion of the plate travelled by the oscillator is derived and solved by the Newmark's time integration procedure. The accuracy of the algorithm is verified by comparing the numerical results with the other numerical results in the literature. Also, the effects of mass and damping ratio of system components, stiffness of suspension system, velocity of moving oscillator, and dynamic foundation parameters on dynamic responses are investigated. A very important role of these factors will be shown in the dynamic behavior of the plate.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.18 no.10
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• pp.1033-1041
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• 2008

The purpose of this paper is to investigate natural frequencies of tapered thick plate with concentrated masses subjected to in-plane force on pasternak foundation by means of finite element method and providing kinetic design data for mat of building structures. Finite element analysis of rectangular plate is done by using rectangular finite element with 8-nodes. For analysis, plates is supported on pasternak foundation. The Winkler parameter is varied with 10, 102, the shear foundation parameter is 5. The taper ratio is applied as 0.0, 0.25, 0.5 and the ratio of the concentrated mass to plate mass as 0.25, 0.5 respectively. As results, we can see that when stiffener's sizes or foundation parameter are larger, the natural frequency increases, and when the concentrated mass or taper ratio or in-plane stress is larger, the natural frequency decreases.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.12
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• pp.1296-1305
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• 2009

This paper has the object of investigating dynamic stability of stiffened tapered thick plate with concentrated mass on Pasternak foundation by means of finite element method and providing kinematic design data for mat of building structures. Finite element analysis of stiffened tapered thick plate is done by use of rectangular finite element with 8-nodes. In order to analysis plate which is supported on Pasternak foundation, the Winkler foundation parameter is varied with 10, 100, 1000 and the shear foundation parameter is 5, 10, concentrated mass is $0.25m_c$, $1.0m_c$, tapered ratio is 0.25, 0.5. The ratio of In-plane force to critical load is applied as $0.4\sigma_{cr},\;0.6\sigma_{cr},\;0.8\sigma_{cr}$ respectively. This paper analyzed varying tapered ratio.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.16 no.6 s.111
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• pp.609-618
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• 2006

This study is undertaken for the vibration analysis of tapered thick plate with concentrated mass on elastic foundation. The boundary condition of the plate is analyzed with the 4-sides simply supported and 4-fixed basis. This study find out the frequency following the change in size for each foundational variable on Pasternak foundation, one of the two-parameter elastic foundation parameter that considered the shear layer to the Winkler foundation parameter. The concentrated mass is applied with the consideration of mass of the entire plate, and the change of frequency is studies on each location with the consideration of reacting for the three locations for concentrated mass. And, in order to find out the change of frequency on the thickness of the plate, it considered tapered ratio that linearly changes depending on the length of the plate with the thickness of the plate in x-direction, and the tapered ratio has changes with 4 types ($\alpha$=0.25, 0, 5, 0.75, and 1.0). For the interpretation, the program using finite element method (F.E.M.) is used and the element coordination is used the 8-node serendipity element. Therefore, the purpose of this study is to find out the characteristics of plate vibration under the mechanica vibration or external vibration factor to facilitate as the basic data of the design to secure the stability.

• Proceedings of the Korea Concrete Institute Conference
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• 1996.04a
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• pp.394-401
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• 1996

This paper persents the crack control of mass concrete in massive machine foundation. The dimension of the machine foundation is 52.6m$\times$14.4m$\times$8.5m. The one distinctive characteristic of mass concrete is thermal behavior. Since the cement-water reaction is exothermic by nature, the temperature rises inside the massive concrete structure. When the heat is not quickly dissipated, it can be quite high. Significant tensile stresses may develop from the volume change associated with the increase of decrease of temperature within the mass concrete structure. To avoid occurrence of harmful cracks due to hydration heat, special attention shall be given to the construction of mass cnocrete structures. The temperature control system of mass concrete is proposed in this paper. This system contains a discussion of materials and concrete mix proportioning, thermal analysis, curing method, temperature control, and measurement of hydration heat. As will be seen throughout the paper, the proposed temperature control system have a great effect on the temperature-related cracks on mass concrete structures.