[en] As for the research on earthquake response of nuclear reactor building embedded in soil, experimental and theoretical investigations has been performed on a model of size (height-3.75 meter, bottom cross section-5x5 meter, weight-173 ton) made of concrete under the financial support of Japanese government. The top of model was excited by an eccentric mass vibration that can generate maximum force of 3 ton. Earthpressures were measured at the bottom and side wall of model, and displacements were also measured at the top of model and ground surface. These tests were conducted at a field site where embedded depth was changed at 5 steps which were 0, 20, 47, 73, 100%. Using these experimental results and soil properties, we studied dynamical characteristics that included resonant frequency, radiation damping, vibrational mode, frequency response and earthpressure distribution around the model at varying embedment by lumped model, cylindrical elastic wave model and FEM models. In case of the lumped system, resonant frequency and radiation damping comparatively identified experimental results with theory at each embedded depth, but pressure distribution curves at the bottom of model must be adopted for calculation of lumped system uniform on sway and triangular on rocking motion. As for cylindrical wave theory, variance of resonant frequency was close to experiment at different levels of embedment but radiation damping was estimated smaller than experimental data in case of a deep embedment over a center of gravity of model. In case of FEM model using thin layer element, displacement on model and ground, variance of resonant frequency, radiation damping at each embedment and earthpressure distribution were identified experimental results respectively

[en] This paper is the further report of the previous SMiRT-4 paper K2/7 in which dynamic behavior by oscillator of deeply embedded model was described. In the previous report, variation of resonant frequencies and damping ratios for various embedded depth were mainly described. As for these results, radiational damping became to great with embedment of building. In this paper, earthquake observation and analytical investigations during earthquake are presented. (orig.)

[en] Regarding the earthquake response of nuclear reactor building embedded in soil, experimental and theoretical investigations has been performed on a model of height-3.75 meter, bottom cross section-5x5 meter, weight-173 ton made of conrete under the financial support of Japanese government (The Science and Technology Agency). The top of model was excited by an eccentric mass vibration that can generate maximum force of 3 tons. Earthpressures were measured at the bottom and side wall of model, and displacements were also measured at the top of model (6 components) and ground surface changed in the steps which were 0, 20, 47, 73, 100% (against the height of model). Using these experimental results and soil properties, dynamical characteristics were studied, including resonant frequency, radiation damping, vibrational mode, frequency response and earthpressure distribution around the model at varying embedment by lumped model, cyclindrical elastic wave model and FEM models (thin layer elements). (Auth.)

[en] This paper is concerned with experimental and analytical studies to investigate dynamic behavior of deeply embedded structures such as nuclear reactor buildings. The principal points studied are as follows: (1) Examination of stiffness and radiation damping effects according to embedded depth, (2) verification for distributions of earth pressure according to embedded depth, (3) differences of response characteristics during oscillation according to embedded depth, and (4) proposal of an analytical method for seismic design. Experimental studies were performed by two ways: forced vibration test, and earthquake observation against a rigid body model embedded in soil. Three analytical procedures were performed to compare experimental results and to examine the relation between each procedure. Finally, the dynamic behavior for nuclear reactor buildings with different embedded depths were evaluated by an analytical method. (orig.)

[en] This work compares the response properties of ortho, meta and para diallyl phthalate (DAP) resin plates and their copolymer plates cast under the same curing conditions. The plates were irradiated with fission fragments and alpha-particles. After irradiation, the plates were etched with a potassium hydroxide, ethanol and water (PEW) solution or an aqueous solution of potassium hydroxide. Enlarged nuclear tracks were observed and counted using an optical microscope. All plates were found to have a detection efficiency of almost 100% for fission fragments, and yet were found to be insensitive to alpha-particles. From the experimental results of finish in curing, ease in cutting, etching speed and heat resistance, the ortho-based plates have been found to be superior to the meta- or para-based plates as a fission track detector