【摘要】：自2008年中國數(shù)字臺網(wǎng)中心運行以來四川省發(fā)生了多次強烈地震,不僅為我國提供了很多高質(zhì)量的固定臺站記錄,還貢獻(xiàn)了很多近場的流動臺站記錄,為我國研究四川地區(qū)的地震動衰減關(guān)系提供了良好的數(shù)據(jù)基礎(chǔ)。在以往研究中由于流動臺站無法按照常規(guī)方法進行場地分類致使大量地震動數(shù)據(jù)無法應(yīng)用到衰減關(guān)系之中。本文將以四川境內(nèi)固定臺站以及汶川余震流動臺站數(shù)據(jù)為基礎(chǔ),應(yīng)用H/V譜比方法劃分流動臺站場地類型,分析固定臺站與流動臺站數(shù)據(jù)之間差異,并將流動臺站數(shù)據(jù)應(yīng)用到四川地區(qū)的衰減關(guān)系的回歸之中,具體工作如下:1.收集整理四川地區(qū)固定臺站的鉆孔資料與Vs30數(shù)據(jù),依據(jù)中國建筑抗震設(shè)計規(guī)范對場地類型的定義以及不同場地類型對應(yīng)Vs30范圍,劃分了113個固定臺站的場地類別。結(jié)合不同場地卓越周期以及反應(yīng)譜形狀特點,并應(yīng)用H/V譜比方法劃分了汶川余震監(jiān)測的51個流動臺站的場地類型。最終劃分為Ⅰ類場地32個、Ⅱ類場地130個以及Ⅲ類場地2個。2.整理并篩選了2008-2015年間Ms3.5-6震中距200km以內(nèi)四川地區(qū)的255次地震125個臺站的強震記錄,分析不同場地類型以及震級的分布特點,Ⅰ類場地主要集中在近場區(qū)域而Ⅱ類場地在各震中距段分布較為均勻。分析加速度峰值(PGA)與反應(yīng)譜的分布特征,并對比了固定臺站與流動臺站消除幾何擴散的平均反應(yīng)譜曲線,發(fā)現(xiàn)流動臺站的反應(yīng)譜值在長周期段大于固定臺站的反應(yīng)譜值。3.將數(shù)據(jù)分為兩組:一組僅含固定臺站記錄;一組同時包含固定和流動臺站記錄。根據(jù)數(shù)據(jù)特點調(diào)整模型,利用隨機效應(yīng)方法分別對兩組數(shù)據(jù)進行衰減關(guān)系回歸分析。對比兩組數(shù)據(jù)的回歸參數(shù)與結(jié)果發(fā)現(xiàn),加入流動臺站數(shù)據(jù)致使衰減關(guān)系的事件內(nèi)殘差變大。分析各震級段PGA與反應(yīng)譜的殘差,結(jié)果表明本文衰減關(guān)系可以很好的估計各震級段固定臺站的地震動PGA與反應(yīng)譜值,但是會低估流動臺站的地震動參數(shù)。將本文結(jié)果與其他研究人員的四川區(qū)域衰減關(guān)系進行對比,發(fā)現(xiàn)本文的PGA預(yù)測結(jié)果與他人的結(jié)果較為近似,但本文較低的給出反應(yīng)譜的預(yù)測值;總體上,本文衰減關(guān)系可以較好的體現(xiàn)四川地區(qū)地震動衰減特性。
[Abstract]:Since the operation of the China Digital Network Center in 2008, there have been many strong earthquakes in Sichuan Province, which not only provided China with a lot of high-quality records of fixed stations, but also contributed a lot of near-field mobile station records. It provides a good data base for studying the attenuation relation of ground motion in Sichuan area. In previous studies, a large number of ground motion data could not be applied to the attenuation relationship because the mobile stations could not classify the site according to the conventional method. Based on the data of fixed station and Wenchuan aftershock mobile station in Sichuan, this paper uses the method of H / V spectrum ratio to divide the site type of mobile station, and analyzes the difference between fixed station and mobile station data. The flow station data are applied to the regression of the attenuation relationship in Sichuan, and the specific work is as follows: 1. According to the definition of site type and the corresponding Vs30 range of different site types, 113 fixed stations are classified according to the definition of site type and the corresponding Vs30 range of different site types according to the definition of site type in Chinese Code for Seismic Design of buildings and the Vs30 data of fixed stations in Sichuan. According to the characteristic of outstanding period and response spectrum shape of different sites, the site types of 51 mobile stations monitored by Wenchuan aftershock are divided by using the method of H / V spectrum ratio. It was divided into 32 sites of class 鈪，

本文編號：2183080