本文關(guān)鍵詞：軟弱層幾何特性與剪切波速對場地反應(yīng)譜的影響研究　出處：《防災(zāi)減災(zāi)工程學(xué)報》2016年05期 　論文類型：期刊論文

  更多相關(guān)文章： 反應(yīng)譜 軟弱土層 場地效應(yīng) 真非線性地震反應(yīng)分析 土的滯回模型 非線性動力特性

【摘要】：場地土層結(jié)構(gòu)對地震動的影響一直備受關(guān)注。針對含有一層軟弱土層的勻質(zhì)場地展開非線性地震反應(yīng)分析,研究了軟弱土層的幾何分布特性和剪切波速變化對地表反應(yīng)譜的影響。結(jié)果表明:1軟弱層使得場地反應(yīng)譜特征周期延長,長周期段曲線升高并出現(xiàn)多峰值現(xiàn)象,含軟弱層場地的反應(yīng)譜與無軟弱層場地的反應(yīng)譜差值比遠大于工程可接受的誤差范圍。2軟弱層所引起的最大反應(yīng)譜差值比隨軟弱層厚度和埋深的增加而近似線性增大,隨軟弱層剪切波速的減小而非線性增加,在本文算例中,最大反應(yīng)譜差值比接近12倍。3反應(yīng)譜最大差值比所對應(yīng)的敏感周期隨著軟弱層厚度、埋深和輸入加速度幅值的增加而增大,隨剪切波速的減小而增大。分析表明,軟弱層中的剪應(yīng)變遠大于鄰近正常土層中的剪應(yīng)變,這是引起地表加速度反應(yīng)譜發(fā)生改變的主要原因。
[Abstract]:The influence of site soil structure on ground motion has been paid much attention. Nonlinear seismic response analysis is carried out for homogeneous site with a layer of soft soil. The effects of the geometric distribution of soft soil layer and the variation of shear wave velocity on the surface response spectrum are studied. The results show that the weak layer of 1 / 1 makes the characteristic period of the site response spectrum longer. The long-period curve increased and appeared the phenomenon of multi-peak value. The ratio of response spectrum difference between site with weak layer and site without weak layer is much larger than that of engineering acceptable error range .2 the ratio of maximum response spectrum difference caused by weak layer increases with the increase of thickness and buried depth of weak layer. Sex increases. With the decrease of shear wave velocity in the weak layer, the nonlinear increases. In this example, the sensitivity period of the maximum response spectrum difference ratio is nearly 12 times that of the maximum response spectrum difference ratio with the thickness of the weak layer. The increase of buried depth and the amplitude of input acceleration increases with the decrease of shear wave velocity. The analysis shows that the shear strain in the weak layer is much larger than that in the adjacent normal soil layer. This is the main reason for the change of surface acceleration response spectrum.
【作者單位】： 湖南工業(yè)大學(xué)土木工程學(xué)院;香港大學(xué)土木工程系;
【分類號】：TU435;P315.9
【正文快照】： 引言軟弱層作為局部場地條件中的一種特殊情況,其對場地地震動的影響一直是地震工程領(lǐng)域重點關(guān)注的問題[1-7]。我國現(xiàn)行規(guī)范對場地條件的考慮僅基于等效剪切波速和覆蓋層厚度劃分場地類別,對于場地中存在的軟弱層不能敏感地反映,可能使地震動參數(shù)取值偏低,造成建(構(gòu))筑物的安，

本文編號：1432350