摘要
隔震用多層橡膠支承墊需要加勁層來束制橡膠的變形，以增加垂直向勁度，使膠墊可穩定的支撐上部結構。和傳統的鋼片加勁不同，以纖維加勁板為加勁層之多層膠墊造價較便宜而且重量輕，在製作上較簡單且費用更低。因此纖維加勁橡膠支承墊之研究和分析將為未來發展之走向。
本研究是利用有限元素法之套裝軟體SAP2000來分析不同厚度及長寬之多層矩形纖維加勁膠墊。以立體元素來模擬橡膠層、平面應力元素來模擬加勁層，並分析探討有效壓縮勁度和有效傾斜勁度及其和各參數間之關係，並對其膠墊因外力所產生的變形及內部的應力之分佈做比較和討論。並且針對過去有關研究的理論推導之兩項位移假設做確認，此兩項假設分別為：1.變形前平行於加勁板之平面，在變形後仍保持平面；2.變形前垂直於加勁板之直線，在變形後成一對稱之拋物線。
由有限元素分析之結果可發現，有效壓縮勁度和有效傾斜勁度皆隨彈性層柏松比、形狀係數增加而變大，而隨勁度比、膠墊總層數愈大而減小。而當膠墊愈接近無限長條形而有效壓縮勁度會愈小；有效傾斜勁度則會隨著長寬比愈大而增大。且有限元素分析之結果對於理論推導之兩項位移假設並不是相同，但卻有一定程度的相似。

Abstract
Laminated rubber bearings used in base isolation require the reinforcing element to constrain the deformation of the rubber to increase the vertical stiffness, so that the bearings can firmly support the superstructure. In contrast to the steel-reinforced isolator, the fiber-reinforced isolator is significantly lighter and could lead to much less labor-intensive manufacturing process, which will become the trends of base isolation in the future.
This research utilized SAP2000, a computer program of the finite element method, to analyze multi-layer fiber-reinforced isolators of rectangular shape for different thickness and aspect ratio. The elastic layer is modeled by the solid element and the reinforcement is modeled by the plane stress element. The variation of effective compressive stiffness and the effective bending stiffness with different parameters is conferred. The deformation of isolators produced of the external force and the distribution of internal stress are discussed. The result can be applied to confirm two assumptions used in theoretical derivation, which are 1.the horizontal plane remains plane after deformed; 2.the vertical line becomes parabolic after deformed.
The research shows that the effective compressive stiffness, and the effective bending stiffness increases with increasing the Poisson’s ratio and shape factor of elastic layers, and decreases with increasing the stiffness ratio of elastomer to fiber or the numbers of elastomer layer. The result of finite element analysis is not consistent with the displacement assumptions used in theoretical derivation, but they are similar in a certain degree.

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