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841246 Improved hammer-impact technique for strong shear wave generation
28A this elastic moduli ratio: as it decreases there is an increase in apparent damping of the dam. The effects of dam- foundation rock interaction are similar whether the reservoir is full or empty, except at the resonant frequ~n'cies of water in the reservoir. In conclusion, the fundamental resonant frequency of the dam is reduced by dam-water interaction and by dam-foundation rock interaction with the relative significance of these two interaction effects depending on the moduli ratio value.
841246 Improved hammer-impact technique for strong shear wave generation Maiguma, T
Earthq Engng Struet Dynam VIO, N1, Jan-Feb 1982, P123133 A series of experiments was performed to improve the field procedures for producing SH waves by using the plank-striking method and to develop more adequate techniques for generating high energy shear waves. Based on the results, a flexible impact device was made, to apply a relatively strong impulse of 500kgm/s at the surface of the ground. This is important in current earthquake engineering as a means of evaluating dynamic characteristics of foundation soils accurately.
841247 Variability of tall building response to earthquakes with changing epicentre direction Yang, J N; Sae-Ung, S
Earthq Engng Struct Dynam VIO, N2, March-April 1982, P211-223 The structural response of a 40-storey building to horizontal ground movement caused by an earthquake is shown to vary greatly with the direction from the building site to the epicentre. The stationary random process model and the evolutionarytype non- stationary random process model are used to represent the ground motion. The former is suitable if the duration of the most intense portion of an earthquake is much longer than the fundamental natural period of the structure.
841248 Horizontally travelling waves in a group of piles taking pilesoil-pile interaction into account Wolf, J P; Von Arx, G A
Earthq Engng Struct Dynam VIO, N2, March-April 1982, P225-237 A reaclor building founded on a large number of piles situated in a layered site is analysed for an historic earthquake assumed to be propagating horizontally. Taking radiation and hysteretic damping into account the frequency-dependent dynamic stiffness is calculated. It is concluded that horizontally propagating waves result in reduced translational seismic input compared to vertical incident waves. Travelling-wave effects increase the pile forces and piles near the boundary are loaded more heavily than those in the centre. In general, horizontally travelling waves govern the design of the structure.
841249 Response of a plate and elastic half-space to harmonic waves Whittaker, W L; Christiano, P
Eartlul gngng Struct Dynam VIO, N2, March-April 1982, P255-266 Analytical results are presented for the dynamic interaction of an elastic flexural plate and an elastic half space subjected to harmonic seismic waves. It is concluded that the flexural response of a massless plate to wave excitation depends on the apparent wavelength of the free-field motion. At low frequencies even a stiff plate is able to comply closely with the freefield motion and hence soil-structure interaction associated
with flexural stiffness is very small. In general, at low frequencies contact stress is nearly zero for very soft plates and increases as flexural stiffness increases.
841250 Apparent propagation velocity of body waves O'Rourke, M J; Bloom, M C: Dobry, R
Earthq Engng Struct Dynam VIO, N2, March-April 1982, P283-294 A procedure for determining the apparent propagation velocity of body waves for a particular site is developed. The predominant direction of ground motion for body waves is determined from three orthogonal acceleration components. After correcting for the effect of the free surface, the resulting angle of incidence is combined with material properties for the top layer at the site to yield an approximate value for the apparent propagation velocity. The method is applied to sites which recorded the 1971 San Fernando earthquake and the 1979 Imperial Valley earthquake. Results compare favourably with measured propagation velocities.
841251 Two-dimensional dynamic analysis of concrete gravity and embankment dams including hydrodynamic effects Hall, J F; Chopra, A K
Earthq Engng Struet Dynam VIO, N2, March-April 1982, P305-332 The analysis assumes the responses of the elastic dams and compressible water are linear, in order to determine the earthquake response of concrete gravity and embankment dams. The dam and fluid domains are treated as substructures and modelled with finite elements. The fluid domain model approximately accounts for interaction between the fluid and underlying foundation medium through a damping boundary condition applied along the reservoir bottom while the dam foundation is assumed rigid.
841252 Hydrodynamic effects in the dynamic response of concrete gravity dams Hall, J F; Chopra, A K
Earthq Engng Struct Dynam VIO, N2, March-April 1982. P333-345 Analysis of hydrodynamic effects in the earthquake response of gravity dams has been developed to consider fluid domains of irregular geometry. The dam and fluid domains are treated as substructures and modelled with finite elements. The concrete gravity dam-fluid systems are idealized as two-dimensional and the dam monolith is idealized as a triangle with vertical upstream face. Three different reservoir shapes are analysed to study the effects of fluid domain geometry on the dam response to both vertical and horizontal ground movement.
841253 Response of Veterans Hospital building 41 in the San Fernando Earthquake Rutenberg, A; Jennings, PC; Housner, G W
Earthq Engng Struet D.vnam VIO, N3, May-June 1982. P359-379 Building 41 of the Veterans Administration Hospital was directly over the causative fault of the 1971 San Fernando Earthquake. This study attempts to reconcile the fact that the building withstood a basal shear of 60 to 130 per cent of the weight of the structure when only designed to withstand 10 per cent. A code-oriented lateral force analysis and a dynamic analysis of a fixed base three-dimensional linear model of the structure both indicate yield at lateral loads of 15-20 per cent of the weight of the building and that the capacity against overturning is 45-50
841246 Improved hammer-impact technique for strong shear wave generation Maiguma, T
Earthq Engng Struet Dynam VIO, N1, Jan-Feb 1982, P123133 A series of experiments was performed to improve the field procedures for producing SH waves by using the plank-striking method and to develop more adequate techniques for generating high energy shear waves. Based on the results, a flexible impact device was made, to apply a relatively strong impulse of 500kgm/s at the surface of the ground. This is important in current earthquake engineering as a means of evaluating dynamic characteristics of foundation soils accurately.
841247 Variability of tall building response to earthquakes with changing epicentre direction Yang, J N; Sae-Ung, S
Earthq Engng Struct Dynam VIO, N2, March-April 1982, P211-223 The structural response of a 40-storey building to horizontal ground movement caused by an earthquake is shown to vary greatly with the direction from the building site to the epicentre. The stationary random process model and the evolutionarytype non- stationary random process model are used to represent the ground motion. The former is suitable if the duration of the most intense portion of an earthquake is much longer than the fundamental natural period of the structure.
841248 Horizontally travelling waves in a group of piles taking pilesoil-pile interaction into account Wolf, J P; Von Arx, G A
Earthq Engng Struct Dynam VIO, N2, March-April 1982, P225-237 A reaclor building founded on a large number of piles situated in a layered site is analysed for an historic earthquake assumed to be propagating horizontally. Taking radiation and hysteretic damping into account the frequency-dependent dynamic stiffness is calculated. It is concluded that horizontally propagating waves result in reduced translational seismic input compared to vertical incident waves. Travelling-wave effects increase the pile forces and piles near the boundary are loaded more heavily than those in the centre. In general, horizontally travelling waves govern the design of the structure.
841249 Response of a plate and elastic half-space to harmonic waves Whittaker, W L; Christiano, P
Eartlul gngng Struct Dynam VIO, N2, March-April 1982, P255-266 Analytical results are presented for the dynamic interaction of an elastic flexural plate and an elastic half space subjected to harmonic seismic waves. It is concluded that the flexural response of a massless plate to wave excitation depends on the apparent wavelength of the free-field motion. At low frequencies even a stiff plate is able to comply closely with the freefield motion and hence soil-structure interaction associated
with flexural stiffness is very small. In general, at low frequencies contact stress is nearly zero for very soft plates and increases as flexural stiffness increases.
841250 Apparent propagation velocity of body waves O'Rourke, M J; Bloom, M C: Dobry, R
Earthq Engng Struct Dynam VIO, N2, March-April 1982, P283-294 A procedure for determining the apparent propagation velocity of body waves for a particular site is developed. The predominant direction of ground motion for body waves is determined from three orthogonal acceleration components. After correcting for the effect of the free surface, the resulting angle of incidence is combined with material properties for the top layer at the site to yield an approximate value for the apparent propagation velocity. The method is applied to sites which recorded the 1971 San Fernando earthquake and the 1979 Imperial Valley earthquake. Results compare favourably with measured propagation velocities.
841251 Two-dimensional dynamic analysis of concrete gravity and embankment dams including hydrodynamic effects Hall, J F; Chopra, A K
Earthq Engng Struet Dynam VIO, N2, March-April 1982, P305-332 The analysis assumes the responses of the elastic dams and compressible water are linear, in order to determine the earthquake response of concrete gravity and embankment dams. The dam and fluid domains are treated as substructures and modelled with finite elements. The fluid domain model approximately accounts for interaction between the fluid and underlying foundation medium through a damping boundary condition applied along the reservoir bottom while the dam foundation is assumed rigid.
841252 Hydrodynamic effects in the dynamic response of concrete gravity dams Hall, J F; Chopra, A K
Earthq Engng Struct Dynam VIO, N2, March-April 1982. P333-345 Analysis of hydrodynamic effects in the earthquake response of gravity dams has been developed to consider fluid domains of irregular geometry. The dam and fluid domains are treated as substructures and modelled with finite elements. The concrete gravity dam-fluid systems are idealized as two-dimensional and the dam monolith is idealized as a triangle with vertical upstream face. Three different reservoir shapes are analysed to study the effects of fluid domain geometry on the dam response to both vertical and horizontal ground movement.
841253 Response of Veterans Hospital building 41 in the San Fernando Earthquake Rutenberg, A; Jennings, PC; Housner, G W
Earthq Engng Struet D.vnam VIO, N3, May-June 1982. P359-379 Building 41 of the Veterans Administration Hospital was directly over the causative fault of the 1971 San Fernando Earthquake. This study attempts to reconcile the fact that the building withstood a basal shear of 60 to 130 per cent of the weight of the structure when only designed to withstand 10 per cent. A code-oriented lateral force analysis and a dynamic analysis of a fixed base three-dimensional linear model of the structure both indicate yield at lateral loads of 15-20 per cent of the weight of the building and that the capacity against overturning is 45-50