地震动随机功率谱模型分析改进及其参数值确定

发布时间：2018-01-13 03:34

  本文关键词：地震动随机功率谱模型分析改进及其参数值确定　出处：《长安大学》2013年硕士论文　论文类型：学位论文

  更多相关文章： 地震动 功率谱 随机振动 功率谱模型改进 参数确定

【摘要】：在地震工程学领域中，地震动功率谱起着非常重要的作用。地震动功率谱模型是用来描述地震地面运动过程能量的频域分布规律，是地震动随机模型的重要组成部分。如果具有充足的地面运动资料，那么就可直接用统计分析来建立地震动随机模型。然而，到目前为止，强地面运动的加速度记录资料仍然非常有限，因此，不得不假设模型的形式。在地震工程领域中，虽然有一些学者提出各种模型，但这些模型都存在一些不足之处，故有必要对地震动功率谱模型进行深入研究。 首先，本文对地震动功率谱模型的研究现状进行了梳理，总结了多种地震动功率谱模型，根据地震动模型的评价标准对目前已有功率谱模型进行了对比分析。 其次，针对彭凌云模型在高低频抑制强度方面的不足之处，本文提出了新的修正彭凌云模型，推导了新模型在单自由度体系下的方差公式。并利用Matlab软件编制程序对本文提出的修正彭凌云模型和彭凌云模型从三个方面进行对比分析，以此验证本文提出的修正彭凌云模型的优势。 最后，收集了Ⅱ类场地条件下的100条实际记录地震波，，根据8度多遇地震对所有地震波的原始信号进行调整，对调整后的各条地震波做傅里叶变换，获得频谱图，进行频谱分析。同时，采用Matlab软件编制程序，利用最小二乘法对平均功率谱曲线进行拟合，进而确定本文提出的修正彭凌云模型的参数值。算例分析结果表明：本文提出的修正彭凌云模型更能合理地描述地面加速度过程，准确反映地震动的实际情况。
[Abstract]:In the field of seismic engineering, seismic power spectrum plays a very important role. The ground motion power spectrum model is used to describe the frequency domain distribution of earthquake ground motion energy. It is an important part of the stochastic model of ground motion. If there is sufficient ground motion data, the stochastic model of ground motion can be established directly by statistical analysis. However, so far. The acceleration records of strong ground motion are still very limited, so we have to assume the form of the model. In the field of seismic engineering, although some scholars have proposed various models. However, there are some shortcomings in these models, so it is necessary to deeply study the power spectrum model of ground motion. Firstly, the research status of the power spectrum model of ground motion is reviewed, and a variety of power spectrum models of ground motion are summarized. According to the evaluation criteria of the ground motion model, the existing power spectrum models are compared and analyzed. Secondly, aiming at the deficiency of Peng Lingyun model in high and low frequency suppression intensity, a new modified Peng Lingyun model is proposed in this paper. The variance formula of the new model under the system of single degree of freedom is derived, and the modified Peng Lingyun model and the Peng Lingyun model proposed in this paper are compared and analyzed from three aspects by using the Matlab software programming program. The advantages of the modified Peng Lingyun model proposed in this paper are verified. Finally, 100 actual recorded seismic waves are collected under the condition of type 鈪

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