數值模擬應用於空心排樁的減振效應之研究

Numerical Simulation of The Effectiveness of Wave Isolation Using Hollow Piles

陳柏村(Bo-Tsuen Chen)

指導教授 ： 張子修

朝陽科技大學/理工學院/營建工程系/碩士(2009年)

摘要

本研究利用電腦軟體分析的排樁種類使用混凝土空心排樁，將以排樁厚度、淨間距、直徑為主要參數，來探討各項參數對單/雙排空心排樁對減震效率的影響，並且找出最佳淨間距。以供工程實務應用。
本研究發現其參數對減震效率影響的程度關係為：淨間距(S)參數 > 厚度(t)參數 > 直徑(D)參數。而本研究發現減震效率會隨著淨間距(S)及厚度(t)減少而顯著增加，目前初步推斷最佳淨間距約在3.6~4.2m(約為2-4倍的直徑)，排樁淨間距要在最佳淨間距以內，隔震效果才會顯著。對單排而言當淨間距等於最佳淨間距時，減震效率約為0.2~0.3左右。當淨間距小於最佳間距減震成效顯著增加，在淨間距為0時，減震效率可達0.5~0.6左右。反之當淨間距大於最佳淨間距時，減震效率下降而較不顯著，約僅達為0.15~0.2左右。在雙排之減震效率比單排稍佳，分別增加0.1左右，其效率增加但不顯著，故實務上雙排隔震並不需要。

關鍵字

空心排樁 ； 數值分析 ； 隔震

並列摘要

The research was conducted to investigate the vibration screening effectiveness of hollow cylindrical piles using an established numerical analysis software ANSYS with parameters of material type, diameter, and clearance spacing of the piles. The main objectives of the study include the effectiveness difference between single and double rows of the piles as well as the “optimum clearance spacing”, which can be useful information in practical applications when the hollow cylindrical piles are used for vibration isolation.
The results of the study indicated that, for the parameters used in the study, the influential level of the parameters on the vibration screening effectiveness can be ranked as the following:
Clearance spacing (S) > thickness (t) > diameter (D).

The study results also revealed that the screening effectiveness increases with decreasing clearance spacing S and thickness t of the piles. In general, the piles exhibit significant increase of screening effectiveness when the clearance spacing is within the optimum spacing which is about 3.6 – 4.2 meters (about 2-4 times of pile diameter). Specifically, the results indicated that the screening effectiveness is about 0.2 – 0.3 when S is equal to the optimum clearance spacing. Also, the effectiveness can be as high as 0.5-0.6 when the S is zero (i.e. piles side by side) while the effectiveness becomes insignificant at about 0.15 – 0.2 for S greater than the optimum spacing. In addition, the screening effectiveness is only about 0.1 higher for the piles in double rows than that for the single row at each clearance spacing level respectively discussed above. This implies that using double rows may not result in significant increase in screening effectiveness and is not recommended for economic reasons in practical applications when hollow cylindrical piles are used for vibration isolation.

並列關鍵字

numerical analysis ； cylindrical pile ； vibration isolation

參考文獻

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