Proposal of vibration evaluation scale considering vibration perception time for vertical vibration in building

We reported that the degree of discomfort increased as the vibration perception time increased. Moreover, it was shown that LVeq,h,Th + kV∗10log10Th corresponded to the degree of discomfort. Furthermore, it was shown that the time correction coefficient kv changes with time. However, the time correction coefficient kv was a value that discretely changed for each time segment in four stages of 1 second or less, 1 to 5 seconds, 5 to 50 seconds, and 50 seconds or more. Hermann Ebbinghaus, a German psychologist, is studying the memory of humans and is investigating the retention of memory during repeated learning. It is shown that the amount of retained memory is proportional to the logarithm of the repeated period when the learning is repeated. This result can also be applied to the vibration sensation of a person exposed to vibration. In this report, in order to study the effect of vibration perception time on human vibration sensation, a new time correction coefficient is proposed as a continuous function. In addition, in order to verify the practicality of the proposed time correction coefficient, we also examined the applicability of actual vibrations such as traffic vibration in addition to impact vibrations caused by rubber balls. As a result, the following findings were obtained. (1) 0.5∗10logTh (20logTh1/4), which is the time correction term, was added too much when the vibration perception time became long, and the response was poor. (2) Discomfort scale is held and becomes constant when the vibration perception time exceeds a certain time. In the range of this study, it became constant when the vibration perception time exceeded about 15 seconds. (3) kC2' in Eq. (9) had the best correspondence with the time correction coefficient as a continuous function. LVeq,h,Th + kC2'∗10log10Th was used as the evaluation index for discomfort scale, and the response was improved. (4) The time correction coefficient kC2' was applicable not only to impact vibration but also to actual traffic vibration. However, this report is an experimental study, and the correspondence between the actual resident reaction and the reaction in the laboratory or field experiment, as well as the setting of evaluation scales, evaluation methods, and performance ranks are left for future study. © 2021 Architectural Institute of Japan. All rights reserved.