超高层建筑群对场地地脉动的影响

Effect of Super-Tall Building Group on Site Ground Pulsation

随着经济与技术的快速发展,高层甚至是超高层建筑不断涌现,城市场地的建筑群效应问题逐渐受到重视.为研究超高层建筑群对场地地脉动的影响,本文以上海浦东某典型超高层建筑场地为背景,采用美国Kinemetrics公司的Basalt型数字加速度采集仪对这一超高层建筑群的区域场地进行了现场振动测试,并对现场实测数据进行了时频分析和振级分析,探讨了超高层建筑群对场地地脉动的影响.分析结果表明:与自由场场地相比,超高层建筑群场地的三个方向的地脉动幅值均有不同程度的减小;超高层建筑群改变了场地地脉动的频谱分布特性,地脉动频带相对变宽,能量更分散;自由场场地的1/3倍频振级总体上大于超高层建筑群场地的振级.

With the rapid development of society and economy, high-rise and even super high-rise building groups are constantly emerging, and effects of building group in urban site become an outstanding issue of civil engineering. In order to study the effect of super high-rise building group on site ground pulsation, the measurement of ground pulsation is conducted in Pudong area of Shanghai by using the Basalt digital acceleration recording instrumentation from Kinemetrics Inc. Field test data was analyzed by using Fast Fourier Transform and Wavelet Transform method, and the influence of high-rise building group on site ground pulsation was discussed. The results show that with respect to free field ground pulsation, the amplitude of ground pulsation in super high-rise-building group site is relatively smaller in all three directions. The high-rise-building group introduces some changes into the frequency spectrum characteristics of the ground pulsation： the frequency band of the ground pulsation in high-rise-buildings group site is wider and energy become more dispersed; the 1/3 frequency vibration level of free field site is generally larger than that of super high-rise building group site.