建筑英文文獻(xiàn)及翻譯(共4頁(yè))

1、精選優(yōu)質(zhì)文檔-傾情為你奉上外文原文出處:, 2009, , Pages 147-149動(dòng)力性能對(duì)建筑物的破壞引言：建筑物在地震的作用下，和一些薄弱的建筑結(jié)構(gòu)中，動(dòng)力學(xué)性能扮演了一個(gè)很重要的角色。特別是要滿足最基本的震動(dòng)周期，無(wú)論是在設(shè)計(jì)的新建筑，或者是評(píng)估已經(jīng)有的建筑，使他們可以了解地震的影響。許多標(biāo)準(zhǔn)(例如：歐標(biāo)，2003；歐標(biāo)，2006)，建議用簡(jiǎn)單的表達(dá)式來(lái)表達(dá)一個(gè)建筑物的高度和他的基本周期。這樣的表達(dá)式被牢記在心，得出標(biāo)定設(shè)計(jì)(高爾和喬譜拉人，1997)，從而人為的低估了標(biāo)準(zhǔn)周期。因?yàn)檫@個(gè)原因，他們通常提供比較低的設(shè)計(jì)標(biāo)準(zhǔn)當(dāng)與那些把設(shè)計(jì)基礎(chǔ)標(biāo)準(zhǔn)牢記在心的人(例：?jiǎn)唐绽竞透郀枺?000

2、)。當(dāng)后者從已進(jìn)行仔細(xì)建立的數(shù)字模型中得到數(shù)值(例：克勞利普和皮諾，2004；普里斯特利權(quán)威，2007)。當(dāng)數(shù)字估計(jì)與周?chē)饎?dòng)測(cè)量的實(shí)驗(yàn)結(jié)果相比較，有大的差異，提供非常低的周期標(biāo)準(zhǔn)(例：納瓦洛蘇達(dá)權(quán)威，2004)。一個(gè)概述不同的方式比較確切的結(jié)果刊登在馬西和馬里奧(2008)；另外，一個(gè)高級(jí)的表達(dá)式來(lái)指定更有說(shuō)服力的堅(jiān)固建筑類(lèi)型，提出了更加準(zhǔn)確的結(jié)構(gòu)參數(shù)表(建筑高度，開(kāi)裂，空隙填實(shí)，等等)。聯(lián)系基礎(chǔ)和上層建筑的震動(dòng)周期可能發(fā)生共振的效果。這個(gè)原因?qū)τ谒麄兊恼駝?dòng)，可能建筑物和土地在非線性運(yùn)動(dòng)下受到到破壞，這個(gè)必須被重視。通常，結(jié)構(gòu)工程師和巖土工程師有不同的觀點(diǎn)在共振作用和一些變化的地震活動(dòng)。結(jié)構(gòu)

3、工程師們認(rèn)為盡管建筑物和土壤的自振周期和地震周期都非常的接近。但對(duì)于建筑物周期而言，到底是因?yàn)榻Y(jié)構(gòu)還是非結(jié)構(gòu)造成的破壞提出了疑問(wèn)。如果加大振動(dòng)，建筑物減輕自身的重量對(duì)共振產(chǎn)生的破壞有很大的減輕效果。巖土工程的工程師們還沒(méi)有完全同意這個(gè)觀點(diǎn)，因?yàn)橥寥揽梢蕴岣咦陨淼恼駝?dòng)周期，與建筑物有相同的振動(dòng)周期，從而建立了產(chǎn)生共振的條件。這個(gè)問(wèn)題的處理在于這個(gè)增加量到底是多少？一般來(lái)說(shuō)這種答案是不可能的，因?yàn)樗Q于建筑類(lèi)型和土壤類(lèi)型。例如，一些普通的混凝土建筑物，對(duì)這建筑物增加一個(gè)非常大的震動(dòng)周期，可以知道在平常的振動(dòng)下就會(huì)迅速的遭到破壞，尤其是那些砌體建筑，比如，馬雪凱利建筑(2004)和克勞福建筑(20

4、06)。最后，估計(jì)在改裝或者加固后參數(shù)表數(shù)字的變化，通過(guò)計(jì)算機(jī)計(jì)算來(lái)改變標(biāo)準(zhǔn)的振動(dòng)周期，阻尼因數(shù)和振動(dòng)波形。這可以是一個(gè)非常好的評(píng)估工具對(duì)于存在的一些干擾(法拉斯等，2008)。這種效果也可以作為一種診斷工具，對(duì)周?chē)恼駝?dòng)測(cè)量很有幫助(布丁和漢斯，2008)。對(duì)以上問(wèn)題的進(jìn)一步研究，強(qiáng)烈要求建立更加寬廣的原地實(shí)驗(yàn)或者是實(shí)驗(yàn)室實(shí)驗(yàn)，得出實(shí)驗(yàn)結(jié)果來(lái)估算。用一個(gè)經(jīng)濟(jì)實(shí)用的方式，來(lái)營(yíng)造動(dòng)態(tài)特性。Role of Dynamic Properties on Building Vulnerability, 2009, , Pages 147-149IntroductionDynamic properties

5、 have a major role on the seismic behavior and vulnerability of building structures. Particularly, fundamental periods of vibration are needed, both in design of new buildings and in assessment of existing ones, so that their seismic response can be evaluated.Several codes (e.g. CEN, 2003; NZSEE, 20

6、06) recommend empirical simplified expressions between the height of a building type and its fundamental period. Such expressions were calibrated keeping in mind a force-based design (Goel and Chopra, 1997), thus intentionally aim at underestimating period values. For this reason they usually provid

7、e rather low values when compared to those ones obtained keeping in mind a displacement-based design (see e.g. Chopra and Goel, 2000), also when the latter were obtained from numerical simulations performed on carefully set up models (see e.g. Crowley and Pinho, 2004; Priestley et al., 2007). Even l

8、arger differences appear when numerical estimates are compared to experimental results based on ambient vibration measurements that provide very low period values (see e.g. Navarro et al., 2004). An overview of the different approaches together with a comparison of the relevant results is reported i

9、n Masi and Vona (2008); further, period-height expressions for some reinforced concrete building types are given, where the role of important structural characteristics (building height, cracking, masonry infills, elevation irregularities, etc.) is carefully taken into account. Coupling between soil

10、 and building fundamental periods of vibration may cause resonance effects. For this reason also their variation, as a consequence of possible building damage and/or soil non linear behavior during the motion, needs to be considered. Typically, structural and geotechnical engineers have different po

11、ints of view about resonance effect and its variation during a seismic motion. Structural engineers say that whereas building and soil have initially close periods and an earthquake occurs, the building period, as a result of structural and non structural damage, is expected to increase during the m

12、otion, so that the building “hides” itself reducing the heaviest effects of resonance. Geotechnical engineers do not completely agree with this opinion saying that also the soil period can shift towards higher values, that is in the same direction of the building one, thus the resonance condition co

13、uld arise again. The question to be dealt with is: how much is the relative amount of that increase? A general answer is not possible, as it depends on building and soil type. For example, in case of reinforced concrete buildings with masonry infill, a very large increase of the building period can

14、be expected with the level of shaking due to cracking of structural members and, particularly, of brittle masonry infill, see e.g. Mucciarelli et al. (2004), Calvi et al. (2006).Finally, estimating the variation of the dynamic characteristics after retrofitting or strengthening interventions, by com

15、puting the modified values of fundamental periods, damping factors and mode shapes, can be a practical tool to evaluate the effectiveness of the intervention (Farsi et al., 2008). To this purpose and also as a diagnosis tool, ambient vibration measurements can be very helpful (Boutin and Hans, 2008).All the above qu