本研究利用動態離心模型試驗，模擬砂土受振情形，並觀察不同位置處加速度歷時與傅氏幅變化量，以分析積層版試驗箱邊界對試驗結果所產生之影響。藉由改變加速度計陣列距箱壁距離與試體相對密度，分別探討（1）試驗箱壁對距邊界不同遠近的加速度計陣列，量測之試驗結果所造成的影響及影響範圍。（2）相對密度改變時，試驗箱邊界對試驗結果所造成的影響。（3）當土壤受振液化時，邊界對試驗結果的影響。 研究結果顯示，加速度計陣列擺放位置受試驗箱邊界效應影響甚大，距箱壁四分之一箱長處的影響變化量平均約10%，而距箱壁二十分之一箱長處的變化量則在20%浮動；砂土相對密度變化受試驗箱邊界效應的影響所占比例較小，符合對積層版剪力試驗箱的期待；試體相對密度變化時，影響百分比變化量改變幅度在±25%；當試體受振液化時，受邊界影響更明顯。 ABSTRACT A series of dynamic centrifuge modeling tests are conducted to simulate sandy soil deposit subjected to base shaking. The aim of this study is to investigate the boundary effects of laminar box on the test data acquired from the accelerometer arrays located at different distances away from the box wall for various relative densities of soil and for the liquefied or non-liquefied soil. The acceleration histories and the Fourier’s spectra measured at different depths are adopted to indicate the severity of boundary effect. The test results show that the horizontal distance between the wall of laminar box and the accelerometer array would affect the test results a lot. The average variations of the amplitude of acceleration are about 10% and 20%, respectively, when the accelerometer array lies at a quarter and one twentieths of container’s lengths, respectively, away from the wall of laminar box. Once the soil liquefies, the boundary effect is more significant. The relative density of soil plays a trivial role on the boundary effects, which agrees with the anticipation for the use of laminar box.
