Abstract
In order to evaluate effects of soil structure interaction on characteristics of traffic vibration propagation to buildings with different foundation type, vibration test was conducted to existing buildings with spread foundation and pile foundation from outside. Based on the results, simple evaluation technique for response of building foundation by ground surface point excitation using thin layer method supposing that traffic vibration derives from surface point excitation. It was shown that effect of soil structure interaction of pile foundation is more predominant than that of spread foundation at low frequency range.