SPECTRUM-BASED PREDICTION RULE FOR PEAK STRUCTURAL RESPONSES DUE TO SEISMIC POUNDING: (PART 1 SDOF SYSTEMS POUNDING AGAINST RIGID STRUCTURES)

摘要

A spectrum method was proposed for predicting peak responses of a single-degree-of-freedom system that pounds against rigid adjacent structure(s) during an earthquake. Pounding was considered to occur on either one side or two sides of the system. The Kelvin body that combines a spring and a dashpot in parallel was used to simulate the collision. Based on free vibration and harmonic vibration both involving pounding, the equivalent period and damping of the system were obtained and used to predict peak displacement as well as collision force. Extensive numerical experiment, which covered a variety of combinations of system properties, contact element properties, separation distances, and earthquakes, demonstrated good accuracy of the proposed method.%地震時に隣接建物が異なる揺れをすると深刻な衝突被害が起こり得る。この対処のため、簡易で極力正確な衝突最大応答の評価法が必要である。衝突を模擬した時刻歴解析によれば応答が予測できるが、ある地震入力における特解を得るだけである。一方で地震応答スペクトルを用いた手法があれば、地震の効果を包絡的に捉え、かつ入力や構造物の特性の効果を陽な形で理論的に表すことができ、衝突問題の理解や設計・評価に有効である。そのような既往手法は僅少であり、また、精度や簡易性の観点から改良の余地がある。