Simulation method of near-fault pulse-type ground motion

• Published in: Acta seismologica sinica Vol. 20; no. 1; pp. 80 - 87
• Main Author: 田玉基 杨庆山 卢明奇
• Format: Journal Article
• Language: English; Chinese
• Published: Beijing Springer Nature B.V 2007
• Subjects: Computer simulation; Directivity; Displacement; Earthquakes; Equivalence; Ground motion; Grounds; Mathematical models; Seismic activity; Seismic phenomena; Simulation; Velocity; 低频时程分量; 模拟方法; 近断层脉冲型地面运动; 高频时程分量
• ISSN: 1000-9116; 1674-4519; 1993-1344; 1867-8777
• DOI: 10.1007/s11589-007-0080-5

The two characteristics of near-fault ground motions, i.e., the forward directivity effect and permanent displacement effect, result in long period and large velocity pulse in the velocity time history and large step pulse in the displacement time history. Considering the two effects, a simple expression of continuous function for equivalent velocity pulse time history is presented in this paper. The equivalent pulse model, in which the pulse period, peak velocity and pulse shape are described by five parameters, is highly advantageous to fit and simulate the pulse-type velocity time history. The equivalent pulse model comprises only one low-frequency component while the high-frequency component of a pulse-type earthquake record cannot be considered. Based on 28 records of 11 earthquakes, the pulse frequency of pulse-type records is generally less than 1 Hz. Therefore the low-frequency component and high-frequency component are simulated respectively and combined them together to generate a pulse-type ground motion.