| Budget Amount *help |
¥1,800,000 (Direct Cost: ¥1,800,000)
Fiscal Year 1990: ¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 1989: ¥1,400,000 (Direct Cost: ¥1,400,000)
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| Research Abstract |
The project has two main objectives : (1) to clarify the vibrating properties of the damaged specimens and (2) to correlate the frequency with the degree of the damage in reinforced concrete tall pier models. The vibrating tests of twelve models are carried out. The variables are the cycle of the repeated loading and the materials of the specimen, that is, normal strength concrete, high strength concrete. And steel fiber reinforced concrete, The results indicate that the relationship between frequencies and the degree of the damage is exhibited by an exponential function. A damage function and so me damage factors are found and defined. Thus, a method for the prediction of the degree of the damage is proposed.
The next paper presents the results of tests made to study the effects of random loading on vibration properties of R/C tall pier models. Two kinds of dynamic tests were carried out. One is the pseudo-dynamic test, another is the shaking table test. Three random waves of acceleration recorded by actual earthquakes in Japan-Miyagi, Hyuuga and Nihonkai-, were induced to the specimen of R/C tall pier models. From the test results, the changes of vibration properties were examined and compared with two kinds of test methods. It is obtained that although the response by shaking table test is three times larger than by pseudo-dynamic test, the degree of damage in frequency is almost the same. It is found that the damage in frequency depends on the rate of loading.
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