抄録
Impact hammer tests were conducted to demonstrate the vertical dynamic characteristics of light frame joist floor and effect of human load on it. The specimen was 3.64m-long-span and 4.55m-wide joist floor consisted of eleven 2" by 8" dimension lumbers and 15 mm-thick plywood subfloor. Furniture and/or human (in four types of posture, respectively) loads were applied to investigate the influence on natural frequencies and damping factors.
The test results indicate, i) Human-load hardly affects natural frequencies, ii) The value of damping factor increases with the body area in contact with the floor, iii) The first natural frequency of joist floor is roughly estimated according to the theory of free vibration equation of motion for bending beam.
