【摘要】 首先介绍了用于地震动数值模拟的国际通用软件COMPSYN程序,并对此进行了二次开发,将其震源时间函数由矩形函数改为钟形函数,通过与全空间的解析解计算结果的对比,验证了修改后程序的正确性。通过对比2种震源时间函数的频谱特点,指出矩形函数的高频成分丰富,不利于地震动的模拟。2种震源时间函数下用COMPSYN程序对同一观测点地震动模拟的结果表明,矩形函数模拟的时程出现"振铃"和"锯齿"现象,且随截止频率的增加而加重,影响了对模拟地震图的识别,而钟形函数模拟的时程较为平滑,说明采用钟形函数进行地震动数值模拟是比较合理的。更多还原

【Abstract】 This paper firstly introduces the worldwide-used COMPSYN software into the numerical simulation of seismic motions,and then makes a second exploitation of it with boxcar source time function replaced by bell function.Validity of modified code is confirmed by comparing it with analytical method in total space.By the comparison between spectrum characteristics of boxcar and bell function,it is pointed out that the boxcar function is rich in high frequencies,which goes against the seismic motion simulation.For the same observation,the seismic simulation results from COMPSYN code with two different source time functions show that the time-history simulated by boxcar function is featured by "ringing" and "serrate" phenomena,and it becomes worse as cut-off frequency grows,which affects the recognition of simulated seismogram,while the time-history simulated by bell function is quite smooth,which explains the rationality of bell function used in seismic motion simulation.更多还原