EARTHQUAKE RESPONSE BEHAVIOR ON STEEL FRAME WITH PARTIAL-STRENGTH CONNECTIONS AND COLUMN BASE DEFORMATION

为了准确评估SHS钢柱试件的抗震性能，进行了自由振动、强迫振动试验和地震监测。利用在天然地震过程中监测到的响应记录来识别试件的振动特性。辨识的系统增益用线性单自由度系统的理论增益来近似，基于这种线性单自由度系统计算的响应与监测响应符合得很好。进行了露天钢柱脚在静力循环双向弯曲作用下的一系列试验。对不同破坏类型、锚杆屈服型和底板屈服型的19 mm和9 mm厚的冷弯方管端板式节点试件进行了单轴、双向线性和双向循环加载试验。磁滞回线的形状、包括双向相互作用面的弯矩能力和旋转Capa…更多的城市得到了实验性的检验。此外，为了考虑部分强度连接中x轴和y轴弯矩的相互作用，我们提出了两种不同的多弹簧模型：一种是底板屈服型，另一种是锚杆屈服型。为了在设计过程中反映裸露柱脚的非线性行为，将裸露柱脚模拟为一种局部强度连接。根据前人的试验结果，提出了一种表征裸式柱脚弯矩-倾角转角关系的典型折线。提出了将单轴恢复力特征模型扩展为双轴模型，分别考虑锚杆屈服型和底板屈服型，来模拟柱脚在双向受弯情况下的弹塑性行为。较少

To estimate the seismic behavior of the SHS steel column specimen of structure with accuracy, free vibration, forced vibration tests, and earthquake monitoring were carried out. The response records monitored during natural earthquakes were used to identify the vibration property of the specimen. Identified system gain was approximated by a theoretical gain of linear SDOF system, and the response calculated based on such a linear SDOF system agrees with the monitored response fairly well. A series of test, which is performed on exposed-type steel column bases under static cyclic bi-axial bending, is carried out. Cold-formed square-tube columns with end-plate type connection specimens (19mm and 9mm thickness) with different failure types, anchor bolt yielding type and base plate yielding type, were tested under uni-axial, bi-axial but linear, and bi-axial circular cyclic loading programs. Shape of hysteresis loop, moment capacity including bi-axial interaction surface, and rotation capa … More city are examined experimentally. Moreover, to consider the interaction between the x-axis and y-axis bending moment in a partial-strength connection, we propose two different multi-spring models : one is base plate yielding type and the other is anchor bolt yielding type. In addition, efficiency of the proposed model is examined by comparing it with the test results.In order to reflect the nonlinear behavior of an exposed-type column base to design procedure, the exposed-type column base is modeled as a kind of the partial strength connection. From the test results of the experiments conducted in the past, a typical poly-line to characterize moment vs. drift angle rotation relationship of exposed-type column base is proposed. Also, a method to simulate the inelastic behavior of column base in case of biaxial bending by expanding uni-axial restoring force characteristic model to bi-axial model is proposed, with respect to anchor bolt yielding type and base plate yielding type, respectively. Less