Behavior of Peak Vertical Acceleration Across Small Two- Dimensional Strong-Motion Array

这是1985年SBIR第二阶段的合同。将研究在距离为50公里或更小的工程兴趣区域内，对多达30次浅层地震产生大约200次高质量观测的地面运动垂直分量在密集二维阵列上的空间相干性。数据由数字记录的垂直加速度图组成，横跨台湾东北部SMART-1阵列的12元内部子阵列（200米半径），加上中央站。丰富的近源强地震动数据使得衰减关系和垂直响应谱的形状有了很大的改善，这两者在工程设计中都是至关重要的，以及它们相关的不确定性。对于投影子阵列，不确定性仅受站点分类的影响最小。地震动参数在时域和频域的频散将作为震源深度、距离、方位和震级的函数进行研究。将评估已知地下结构的影响和土柱的非弹性响应（不同程度的震动）。了解美国西部外密集阵列上垂直加速度的近源行为，可以独立验证垂直和水平地面运动参数之间的假设关系，并设计新的场地特定衰减规律和响应谱，这两者在设计中都具有工程重要性。

This is a 1985 SBIR Phase II award. Spatial coherence of the vertical component of ground motion across a dense two-dimen- sional array for as many as 30 shallow earthquakes which produced approximately 200 high quality observations over a small area of engineering interest at distance of 50 km or less will be studied. The data consists of digitally recorded vertical accelerograms, across the 12-element inner-ing subarray (200m radius) of the SMART-1 Array in northeastern Taiwan, plus the central station. The abundant near-source strong ground motion data permit major improvements in the attenuation relation and the shape of vertical response spectra, both of critical impor- tance in engineering design, and their associated uncertainties. For the projected subarray the uncertainties are only minimally affected by site classification. Dispersion of the ground motion parameters in time and frequency domains will be studied as a function of source depth, distance, azimuth and magnitude. The impact of known subsurface structure and the anelastic response of the soil column (for different levels of shaking) will be evaluated. Understanding of the near-source behavior of vertical acceleration across a dense array outside the western U.S. allows independent verification f assumed relationship between vertical and horizontal ground motion parameters and devise of new site specific attenuation law and response spectra both of engineering importance in the design.