- 期刊
雙軸向動態試驗系統之動態特性識別與探討
Investigation of the Essential Parameters of the Bi-Axial Dynamic Testing System in the Tainan Laboratory
摘要
目前有助於隔震技術研發與隔震支承測試的大型壓剪試驗機，尤其是具有動態控制能力者，鮮少甚至不曾公開其動態特性與系統參數識別的研究報告。因此，對於國家地震工程研究中心雙軸向動態試驗系統提供研究與測試服務前，本研究規劃與執行一系列不同水平速度與位移振幅的三角波循環載重試驗，以及不同振動頻率與位移振幅的正弦波循環載重試驗，建立系統摩擦力（係數）與水平速度的關係式，並識別慣性力（等效質量），以更為清楚瞭解與掌握其動態特性。主要研究內容為三個階段：（1）第一階段為在未加裝隔震支承下，進行一系列的三角波與正弦波循環載重試驗，其目的為求得試驗系統於垂直向空載下，對應不同水平速度之系統摩擦力（係數）與慣性力（等效質量）；（2）第二階段採用經潤滑平面滑動摩擦隔震支承，於施加垂直軸向荷載為10MN下，分別進行三角波與正弦波之循環載重試驗，並提出一迭代分析方法，識別系統摩擦力（係數）與水平速度之關係式；（3）最後，將鉛心橡膠隔震支承與直接剪力測量系統串聯，使其排除試驗系統摩擦力和慣性力，進行一系列測試，並透過試驗結果的比較與探討，進一步證明雙軸向動態試驗系統數學模型的可靠性和直接剪力測量策略的可行性。
並列摘要
Large-scale testing machines with dynamic compression and shear testing capabilities play a crucial role in developing seismic isolation technology and testing full-scale seismic isolators. However, to date, relatively little research has been conducted on its dynamic performance verification and system parameter identification. Only a few studies have established the empirical model to predict the relationship between system friction and peak velocity of the Caltrans seismic response modification device (SRMD) test system in the University of California, San Diego (UCSD), based on the various characterization testing. To support academia and industry, the dynamic characteristics of the biaxial dynamic testing system (BATS) at the National Center for Research on Earthquake Engineering (NCREE) must be thoroughly investigated. When no specimens are installed, the system friction of BATS generated by the various sliding surfaces can be identified and mathematically characterized using the horizontal triangular reversed loading test results; then, the effective mass of BATS can be estimated using the horizontal sinusoidal reversal loading test results to solve the inertia force problem. Under vertical compression loading, it is assumed that the system friction of BATS and the shear force of the specimen are simply related to the applied total normal force (or vertical compression load) and horizontal excitation rate. An iteration methodology is proposed to identify and mathematically describe the dependency of the friction performance of BATS and the specimen on total normal forces (or vertical compression loads) and horizontal excitation rates by iterating the horizontal triangular and sinusoidal reversed loading test results. To simplify the tests, a lubricated flat sliding bearing is used as the specimen, subjected to horizontal triangular and sinusoidal reversed loading with a constant vertical compression load. The reliability of the proposed mathematical model for BATS and the feasibility of the proposed direct force measurement strategy are further demonstrated by comparing the calibrated force response with the directly measured response.