土木工程专业英语unit-2(2)课件.ppt

1、1.vibratory 2.slippage3.fault4.rupture5.epicenter6.seismic 7.agitation Review振动的 滑动、错动 断层 断裂 震中,中心 地震的 震动 seismic performance magnitude of earthquakes intraplate earthquakeinterplate earthquakeRichter scalePhrases耐震性能震级板内地震边缘地震里氏震级不能表示出一次地震震动的全过程，而只能指出地震造成的主冲力方向。不能表示出一次地震震动的全过程，而只能指出地震造成的主冲力方向。n Mea

2、surement of earthquakesn 地震测量n Earthquakes are complex multi-dimensional phenomena,the scientific analysis of which requires measurement.n 地震是一种复杂的多维现象。对地震的科学分析需要测量手段。Prior to(在在.之前之前)the invention of modern scientific instruments,earthquakes were qualitatively measured by intensity,which differed f

3、rom point-to-point.在现代地震测量手段的发明之前，对地震强度进行定性测量，在现代地震测量手段的发明之前，对地震强度进行定性测量，这与点对点的地震测量方法不同。这与点对点的地震测量方法不同。With the development of seismometers,an instrumental quantification of the entire earthquake eventthe unique magnitude of the eventbecame possible.随着地震仪的发明，我们能对整个地震的震级进行测量。随着地震仪的发明，我们能对整个地震的震级进行测量。

4、nMagnitudenThe total strain energy released during an earthquake is known as the magnitude of the earthquake and it is measured on the Richer scale.n地震过程中释放的总应变能被称为震级。它用里氏单位来作为衡量尺度,n It is defined quite simply as the amplitude of the recorded vibrations on a particular kind of seismometer located at

5、 a particular distance from the epicenter.n被简单定义为与震中相隔特定距离处的某种特定地震仪上所显示出的震动幅值。The magnitude of an earthquake by itself,which reflects the size of an earthquake at its source,is not sufficient to indicate whether structural damage can be expected at a particular site.震级本身仅仅反映出地震源头处的大小，不能通过它来预测该次地震对建筑

6、物的损害程度。The distance of the structure from the source has an equally important effect on the response of a structure.建筑物与地震源头的距离对建筑物对该次地震的反应有着重大影响。Seismic intensity is a measure of the effect,or the strength,of an earthquake hazard(灾害、灾难)at a specific location based on observed human behavior and str

7、uctural damage.地震强度是指根据特定地区人员伤亡和建筑物损害程度对地震的大小和灾害影响进行衡量的尺度。damagedisastercalamitycatastropheaccording toin accordance within line within the light ofuponIntensityThere is one type of earthquake disasters that little can be done about.有一种地震灾害，我们对其束手无策。This is the disaster caused by seismic sea waves,o

8、r tsunamis.In certain area,earthquakes take place beneath the sea.These submarine earthquakes sometimes give rise to(导致)seismic sea waves.这种灾害是由海浪，海啸引起的。在某些地区，地震是在海底发生的，这种海底地震能够引发海浪。occurhappencome up 2004年12月26日,8时58分55.2秒 在印尼苏门答腊西北近海(北纬3.9,东经95.9)发生8.7级地震。地震造成印度洋板块移动30米，多个岛屿发生位移。这次地震引起印度洋大规模海啸，遇难总

9、人数近30万。印度洋海啸印度洋海啸印度海啸汽车被淹没印度海啸汽车被淹没 印度马德拉斯市遭遇海啸时的情景印度马德拉斯市遭遇海啸时的情景 海啸过后的印度马里纳海滩鸟瞰图海啸过后的印度马里纳海滩鸟瞰图 发生海啸后的场景发生海啸后的场景 印度洋海啸印度洋海啸The waves are not noticeable at sea because of their long wave length.但是，由于波长较长，这种海浪并不明显。But when they roll into(涌入)harbors,they pile up(堆积)into walls of water 6 to 60 feet hi

10、gh.The Japanese call them“tsunami”,meaning“harbor wave”,because they reach a sizable height only in harbors.但当其涌入海湾时，就会堆成一堵高达6至60英尺的水墙。因为它们只有涌入海湾时才会达到一定的高度，所以日本人称之为“海啸”，意思就是“港湾波”，obviousapparentremarkableprominentconspicuousreach a hight of达到.高度Tsunamis travel fairly slowly,at speed up to 500 miles

11、an hour.海啸的推进速度缓慢，每小时为500英里。An earthquake warning system is in use to warn all shores likely to be reached by waves.地震警告系统用于警告所有海浪可能到达的海港But this only enables people to leave the threatened shores for higher ground.There is no way to stop the oncoming wave.但是，这仅仅能够使人们离开受威胁的海港，来到较高海拔地面上，却无法阻止海浪的到来。up

12、comingforthcomingimminentEarthquake engineering is the study of the behavior of buildings and structures subject to seismic loading.地震工程学是一门基于地震载荷来研究房屋建筑结构的学科。It is a subset of both structure and civil engineering.The main objectives of earthquake engineering are:它是土木工程和结构工程的一个子集。地震工程学的主要目标是：based o

13、naccording toin accordance withuponon the basis ofin line withUnderstand the interaction between buildings or civil infrastructure and the ground.理解建筑物或土木基础设施与地面的相互作用。Foresee the potential consequences of earthquakes预测地震的潜在影响。Design,construct and maintain structures to perform at earthquake exposure

14、 up to the expectations and in compliance with(遵循、遵从)building codes.达到设计，施工，维持结构在地震暴露中的期望值，并且遵循建筑规范。adhere toabide bycomply withkeep toA properly engineered structure does not necessarily have to be extremely strong or expensive.一个合理设计的建筑结构不需要昂贵的造价。The most powerful and budgetary tools of earthquake

15、 engineering are vibration control technologies and,in particular,base isolation.振动控制技术是地震工程学中强有力的预算工具，尤其是基础隔振技术。especiallyparticularlySeismic loading means application of an earthquake-generated agitation(搅动)to a structure.地震荷载是指地震对建筑物产生搅动的应用。It happens at contact surfaces of a structure either wit

16、h the ground,or with adjacent structures,or with gravitational waves from tsunamis.它发生在建筑结构与地面，或是临近结构的接触表面,或是发生在结构与海啸引起的引力波的接触表面。Seismic loading depends,primarily,on:Anticipated earthquakes parameters at the siteGeotechnical parameters of the siteStructures parametersCharacteristics of the anticipat

17、ed gravitational waves from tsunami地震载荷主要取决于：1）预期的地基地震参数；2）地基的岩石参数；3）结构参数；4）海啸引发的预期引力波的特性。rely onlie onhinge withrest withSeismic performance analysis or simply,seismic analysis is a major intellectual tool of earthquake engineering which breaks the complex topic into smaller parts of building and n

18、on-building structures.这个概念是最近才提出来的。The technique as a formal concept is a relatively recent development.抗震分析者简单说是地震分析，是地震工程学的一门知识工具。它把建筑学和非建筑学中复杂的问题细分成几个小题目。In general,seismic analysis is based on the methods of structural dynamics.总的来说，地震分析依赖于结构动力学。For decades,the most prominent instrument of seis

19、mic analysis has been the earthquake response spectrum method,which also contributed to the proposed building codes concept of today.几十年来，最显著的地震分析工具就是地震测量仪，促使了今天建筑规范概念的提出。conduce tobe conducive to promoteremarkablenoticeableconspicuousarrestingHowever,those spectra are good,mostly,for single-degree-

20、of-freedom systems.Numerical step-by-step integration,applied with the charts of seismic performance,proved to be a more effective method of analysis for multi-degree-of-freedom structural systems with severe non-linearity under a substantially transient process of kinematic excitation.然而，这些光谱对于单自由度

21、系统来说是非常好的。经证明，在非线性瞬态过程运动学励磁分析下，数值的逐步逼近法与抗震性能图表结合在一起，是分析多自由度系统结构的一种有效方法。In spite of the great progress obtained in the field of earthquakes engineering during the past fifty years,recent destructive earthquakes occurred around the world revealed that the existing knowledge and techniques are still no

22、t sufficient to achieve safety against earthquakes at an effective cost.尽管过去50年在地震工程领域取得了巨大进步，近来发生在世界范围的破坏性地震仍然表明现有知识和技术还不足以实现合理成本下的地震安全。It is believed that among all natural hazards earthquakes are still number one disaster for which in-depth research,particularly for those devastating earthquakes,

23、the basic research on earthquake engineering is still in need to expand our knowledge and strengthen our defenses.我们相信在所有自然灾害中，地震仍然是需要深入研究的头号灾难，特别是那些破坏性地震，仍需要通过地震工程的基础研究扩充我们的知识并加强我们的防御能力。Exercises（练习）（练习）nI.Read the whole passage and answer the following questions.n1.What is earthquake?n2.Which zone

24、s are the largest earthquakes happen in China?n3.What are the main objectives of earthquake engineering?n4.What factors do the seismic loading depend on nTranslate the following terms into English.断层区域 inertial forcen耐震性能 seismic waven静力模型 acceleration of gravityn刚性结构 harmonic motionn现浇混凝土 calcium c

25、arbonaten平衡原理 line of actionnn基础沉降 load actionn风洞试验 rectangular coordinate axesn人口的平均密度 dead load and live loadn传递机理 strength and stability criterianTranslate the following sentences into Chinese or English.nEveryday,regions of high seismicity experience many small earthquakes;however,structural dam

26、age does not usually occur until the magnitude approaches 5.0.Most structural damage during earthquakes is caused by the failure of the surrounding soil or from strong shaking.nSeismic performance analysis or,simply,seismic analysis is a major intellectual tool of earthquake engineering which breaks the complex topic into smaller parts to gain a better understanding of seismic performance of building and non-building structures.n有碳酸钙所产生的碱性化学环境使钢筋表面形成一种钝化膜，从而使钢筋比其在中性或酸性环境中的抗锈蚀性高得多。n在潮湿和寒冷天气下，受防冻剂作用的钢筋混凝土道路，桥梁，停车结构以及其他结构可得益于环氧图层钢筋，热度钢筋或不锈钢筋的使用，但在许多场合，良好的设计和精选的水泥拌合料就能对钢筋起到足够的保护作用。Thank You!