填充槽溝材料對沉埋基礎垂直振動阻隔效率之研究

Screening Effect of Embedment Foundational Vertical Amplitude by Material Property of Rectangular Strip In-Filled Trench

洪昌祺(Chang-Chi Hung)

《蘭陽學報》 11期 (2012/06) Pp. 15-23

https://doi.org/10.6665/JLYIT.2012.11.15

摘要

本研究利用二維頻率域邊界元素法，分析條形基礎受垂直簡諧外力作用下，以填充槽溝來阻隔震波，透過改變槽溝之填充材料性質，如填充材料與土壤介質間之阻抗比、剪力波速比、密度比、阻尼比等參數，作一系列震波阻隔效果分析，作為日後填充槽溝材料設計選擇參考。研究中發現，填充材料與土壤介質間之阻抗比及剪力波速比為振動基礎阻隔控制效果的主要影響參數。當材料阻抗比相同，密度比改變會使得所得到的平均垂直振幅降低比之值會有些許不同，但對整體阻隔效率之趨勢而言，大致上影響不大。且從此研究中看出，相同的密度比下，不同波速比有明顯不同之平均振幅降低比，且波速比愈大或愈小，震波阻隔效率越佳。

關鍵字

邊界元素法 ； 槽溝 ； 震波 ； 阻隔 ； 阻抗

並列摘要

The screening effects of embedment foundational vibration by the in-filled trenches are solved using the two-dimensional boundary element method (BEM) in frequency domain. Dimensionless parametric studies are performed to assess the screening effects of the trench in terms of in-filled material, such as impedance ratio, density ratio, damping ratio and shear wave velocity ratio of in-filled material to the surrounding soil. Results show that the screening effectiveness of the in-filled trench depends highly on the impedance ratio and the shear wave velocity ratio of the in-filled material to the surrounding soil. When in-filled material of the impedance ratio is same, the change of density ratio and damping ratio are relatively unimportant. The study shows an increase or decrease in the wave velocity ratio results in improved screening of waves in the same density ratio.

並列關鍵字

boundary element method ； trench ； surface wave ； isolation ； impedance

參考文獻

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