| Estimation of strong ground motion in near field is an important issue for earthquake engineering. Since the first strong earthquake is recorded in 1933, researchers began to investigate the attenuation of the ground motion. Twenty-seven strong seismological observatories setup in Pu'er ad Xishuangbanna area have successfully acquired some valuable datas for strong earthquakes. Ground motion in near field when a strong earthquake happens can be predicted, through studying the ground motion in the study area, thus providing a referential basis for earthquake-resistant design and earthquake-safety assessment.In this dissertation, the S wave velocity structure beneath the Pu'er and Xishuangbanna area is acquired by a popular teleseismic receiver function inversion. Based on this initial model, a more accurate S wave velocity structure is got using surface wave data. Using this velocity structure, the peak values of acceleration, velocity and displacement can be obtained through a random vibration theory. The predicted values are compared with the observation from a Ninger earthquake that happened in 2007. Also, the result from a regression attenuation formula is compared with the prediction. Following are several specific results that I obtain.(1) Teleseismic data acquired from 2008 to 2009 at six digital stations deployed in the Pu'er and Xishuangbanna area are collected and used to invert for the S wave velocity structure beneath the stations through the receiver function technology. The result reveals that the crustal thickness is 36 km beneath the northern Jinggu and Simao stations, while that beneath the southern gradually thins from the north to the south. The crustal thickness beneath the Menglian, Lancang and Mengla stations is approximately 32 km, with the thinnest place occurring at Jinghong, with a value at only 30 km. Through the even value of the six velocity structure values, we can see that the thickness of lower-crust is 15km in the aera, and the Moho is about 32km deep, where the velocity changes from 3.85km/s to 4.65km/s, and at a depth of 4 km, the S wave velocity changes abruptly, implying for a velocity discontinuity.(2) Seismic data acquired in 2008 having epicentral distances from 1000 to 3000 km are collected from six digital stations in the study area. Using the Multiple Filter Technique to the surface waves, the group velocity was calculated. The fundamental-mode surface wave was calculated through the Phase-Matched Filter method. Then, the interstation Green's function is also calculated from the two fundamental surface wave signal recordered by the two stations located in the same great circle, and the interstation attenuation coefficients with the period of 10-75s are acquired. The distribution of Qβof the Pu'er and Xishuangbanna area is inversed with the even S velocity and even attenuation coefficients. The value of Qβis pretty low, with the highest Qβat only 180 or so. In the shallow crust, Qβis less than 20, corresponding to a low velocity. Thus the study area, having a fast attenuation and a low velocity, is tectonically active.(3) Using the acquired velocity structure model, the peak values of acceleration, velocity and displacement can be estimated through a random vibration theory. Taking the Ninger earthquake in 2007 as an example, the predicted values are compared with the observation, and the results indicate that they agree with each other very well in the case of the epicentral distances within 200 km. Additionally, the predicted acceleration in near field is similar to that from a regression attenuation formula. It is demonstrated that the random vibration theory is feasible in predicting the peak value of ground motion, thus providing a reference for earthquake-resistant design.
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