外文翻译一六

高层结构与钢结构近年来，尽管一般的建筑结构设计取得了很大的进步，但是取得显著成绩的还要属超高层建筑结构设计。最初的高层建筑设计是从钢结构的设计开始的。钢筋混凝土和受力外包钢筒系统运用起来是比较经济的系统，被有效地运用于大批的民用建筑和商业建筑中。50层到100层的建筑被定义为超高层建筑。而这种建筑在美国得广泛的应用是由于新的结构系统的发展和创新。这样的高度需要增大柱和梁的尺寸，这样以来可以使建筑物更加坚固以至于在允许的限度范围内承受风荷载而不产生弯曲和倾斜。过分的倾斜会导致建筑的隔离构件、顶棚以及其他建筑细部产生循环破坏。除此之外，过大的摇动也会使建筑的使用者们因感觉到这样的的晃动而产生不舒服的感觉。无论是钢筋混凝土结构系统还是钢结构系统都充分利用了整个建筑的刚度潜力，因此不能指望利用多余的刚度来限制侧向位移。在钢结构系统设计中，经济预算是根据每平方英寸地板面积上的钢材的数量确定的。实际上常规框架的平均单位的重量随着楼层数的增加而增加的情况。而曲线，还有是在框架被保护而不受任何侧向荷载的情况下的钢材的平均重量。上界和下界之间的区域显示的是传统梁柱框架的造价随高度而变化的情况。而结构工程师改进结构系统的目的就是减少这部分造价。钢结构中的体系：钢结构的高层建筑的发展是几种结构体系创新的结果。这些创新的结构已经被广泛地应用于办公大楼和公寓建筑中。刚性带式桁架的框架结构：为了联系框架结构的外柱和内部带式桁架，可以在建筑物的中间和顶部设置刚性带式桁架。1974年在米望基建造的威斯康森银行大楼就是一个很好的例子。易框屿架猾筒济结蝇构锣：环讲如女果京所测有隙的腹构顿件罚都县用伴某扁种渗方膨式渐互满相青联逢系滋在勇一磨起畏，吗整挑个制建弃筑叔就葱像命是舟从住地跪面本发叠射荡出钱的弓一豆个泡空删心连筒容体旁或篮是饥一榴个细刚披性麦盒盖子现一生样治。攀这殖个趋时喊候切此脏高谱层寺建协筑估的朴整抗个凯结歪构衣抵妖抗橡风病荷脑载您的串所陡有超强里度趣和贵刚躁度块将削达墙到离最初大咬的坚效浇率失。婚这垒种浩特碎殊机的帝结辈构练体鼠系蝇首挨次摔被润芝跌加幼哥径的乘4盐3浩层类钢路筋迷混国凝培土贷的可德竞威嗽特著红己棕早色谱的侨公游寓汉大古楼飞所时采宏用滨。旧但瓶是插这忌种伙结科构补体召系湖的取的纸所颂有闯应嫁用蜘中榆最翁引展人记注该目弦的零还卡要涌属劫在断纽油约槽建截造横的唱1蜻0防0滋层驼的喝双鱼筒戴结明构贿的选世扑界辈贸款易陶中季心推大森厦逼。勿斜孔撑爱桁民架岭筒撑体趋：贼户建糊筑随物筑的抚外掉柱步可堂以归彼泳此舍独墓立桶的宁间羽隔榴布碌置伤，贩也森可拦以偶借厦助迎于伐通拦过奉梁语柱征中衫心阵线前的葬交额叉票的亏斜欣撑束构佩件拆联胳系类在保一鞭起斥，捧形歇成帖一啊个上共炮同绘工哑作袄的捡筒谎体潮结夺构氏。核这与种输高严度恐的券结显构恰体捎系皆首销次蜻被废芝假加慨哥拨的溪J哑o屠h泥n戒截H拣a学n钳c爆o紧c干k规宣中后心锅大尾厦饿采犯用份。蝴这妹项薄工渗程俊所像耗惑用域的习刚秧才叛量伐与星传楚统台的需四联十珍层掉高推楼全的童用浪钢既量岁相篮当姑。夹筒类体么：葬衔随系着佳对蹄更亲高煮层榴建部筑逐的燃要抚求联不暑断适地徐增歇大连。煎筒搏体喊结艺构园和沃斜坛撑命桁近架解筒稳体返被们设问计愈成净捆巩束扁状结以针形壳成育更粮大亦的条筒轨体外来示保恼持偿建肯筑朱物塘的弹高拖效宗能沸。滔芝坐加游哥舰的阳1裳1祥0用层榜的凑S目e岛a责r急s裙葬R馆o躁e抓b岔u进c稳k贸执总游部恭大污楼骄有丰9闯个禽筒你体伪，甜从座基肥础松开鞠始投分倚成向三肿个奸部涝分坑。滤这丝些福独嘉立各筒仁体莫中档的莫终地端浓处浪在旬不特同房高恰度湖的骂建台筑受体迟中名，绍这视充谎分樱体搜现恐出蜓了缓这直种厚新兆式社结挣构耀观欲念饱的鬼建层筑寿风绞格述自因由订化尖的沈潜屠能遇。衫这尸座偶建宰筑惩物亭1欧4发5脏0阻英能尺丧（逼4曲4酷2角米逐）跑高歪，知是址世踪界隙上好最敬高红的集大姿厦垦。满薄围壳垦筒吹体汇系茂统赵：丝这壶种转筒朝体率结许构锈系来统次的浇设兼计窑是经为挨了中增蔽强瞒超千高枪层她建碌筑橡抵渣抗故侧的力测的滑能尝力宵（篮风灰荷畅载拐和咐地董震丈荷赚载求）妈以羽及疯建臣筑血的杯抗避侧缩移渠能望力和。辟薄叛壳肿筒咸体涝是喘筒煎体真系犹统尸的慢又变一坡大秆飞奔跃碗。胶薄票壳齐筒规体沫的循进虽步京是跌利摸用谊高嫂层学建领筑狗的显正芳面跌（巨墙者体下和穗板刃）恢作甩为注与渔筒犁体毙共干同供作蛛用广的惕结患构析构扮件毅，兆为熔高隙层鱼建某筑谈抵卧抗鞭侧鞭向女荷猪载济提享供爽了爷一明个倾有卧效日的底途判径捐，隆而坡且棉可男获施得凡不寒用沾设淹柱扣，个成躬本顺较她低球，臭使择用六面旗积爬与壁建盾筑仇面所积吵之廉比程又填大休的故室查内芹空唇间袖。应由富于泉薄沫壳棉立誉面票的拒贡老献并，什整杰个疲框战架富筒牵的减构长件见无得需仔过闻大暗的揪质省量邪。俯这有样陆以助来紫使煎得全结廉构奴既膏轻段巧抗又垃经悲济卖。鼻所面有党的浮典照型会柱缩和允窗爬下裳墙可托幅梁采都傲是备轧搂制嚼型般材记，梅最仆大至程索度植上梢减扯小锅了性组溜合属构涂件民的慨使穴用缝和慕耗烘费超。乐托串梁表周各围拾的粪厚哲度破也金可辅适送当温的卧减歇小春。脑而挪可滋能彼占足据居宝薪贵宜空伯间求的脾墙惨上粉镦京梁斑的亮尺遭寸钳也杰可俘以袄最招大缸程邀度颜地友得幼到州控扭制陪。夺这冤种法结随构极体雹系孤已渣被利建讨造致在暑匹部兹请堡肃洲遇的唉O唱n蚕e锻妇M慰e勺l冷l设o赖n拣银你行找中侵心炸所匪运坛用誉。旁钢保筋齐混离凝驼土养中徐的召各袜体爽系著：称虽枕然陪钢贿结香构鞠的怠高剥层风建胀筑祥起席步情比尝较榴早俗，吗但帅是的钢产筋树混传凝腐土造的吓高摘层昏建为筑绪的再发逃展爷非吴常日快岔，巧无旺论第在经办们公寺大铃楼摇还阔是告公旅寓仔住匹宅钥方灿面谎都候成渡为谱刚斜结辞构沫体历系拘的僚有东力验竞库争殿对贡手嗽。领框沫架矛筒俘：间像有上嗓面盏所猎提翁到蚁的点，笼框颜架袍筒蜂构斤思忽首土次柳被质4乒3迟层晚的靠迪隐威豆斯熔公绍寓窃大警楼仿所他采炕用傲。宅在街这毛座达大龟楼值中施，肯外牲柱专的死柱载距道为响5默.美5艘英崭尺骂（插1宪.顾6熄8恢米询）炉。俩而代内甲柱动则侵需钱要弟支践撑屿8鼓英捞寸国厚甜的慢无因梁聋板意。斜筒兴中晚筒迁结很构椒：失另婚一找种紧针趋对嫩于午办勉公扭大棚楼幅的违钢冷筋纺混斑凝废土钉体帆系杠把愈传验统事的驼剪数力刻墙品结盐构捆与批外欠框胶架没筒搁相光结贯合捉。载该嗓体恋系宾由意柱答距唇很陈小苹的娃外之框怪架霉与漆围否绕构中拴心亩设僚备闻区英的森刚贵性券剪唉力豪墙抱筒筒组付成而。绵这启种脚筒袋中杯筒秒结钟构娘（全如圆插榆图堪2球）路使锤得争当叙前恒世概界您上居最洋高型的价轻宋质福混侍凝扣土松大书楼详（胡在古休久斯练顿数建辱造柿的昨独兰壳引购碑物策中购心授大躬厦据）缎的闻整察体颤造混价含只优与吐3寻5安层抹的庆传稍统顿剪袄力室墙糕结燕构说相胁当知。朵钢赞结阳构处与怖混忙凝蝶土令结如构盟的技联鬼合销体农系闸也稠有谣所搬发要展撤。庄S坐k略i是d司m姜o忽r冬e枕著,狭O疑w孩i终n幅g纸s类窃和怪M盯e休r泥r协i衡l偿l笑共雀同锻设财计恨的涂混匙合晋体泄系括就嘴是沟一斜个站好痛例驾子对。很在若此肆体疑系母中胜，纠外涂部弦的修混绑凝化土旺框倍架呈筒壤包导围惯着肾内循部抄的谣钢乡框岩架蒸，谈从察而愿结膝合横了仆钢醒筋间混狠凝屯土版体嘴系慕与垂钢订结液构战体贪系陷各巧自挡的卡优念点新。财在陪新堆奥喝尔铲良翁建洋造晨的馋5强2罚层统的榆独老壳锐广朵场舰大哪厦线就万是达运听用输了奏这丢种洗体谢系所。喇钢租结乔构由是耽指雀在恰建放筑舞物近结考构瓦中局钢咏材绪起索着桥主艘导维作昼用春的臭结驶构芦，学是辉一他个馋很冶宽材泛睡的岗概锡念锈。浊大候部埋分者的送钢冲结惕构念都氧包闹括虑建恭筑踏设春计狼，喷工捕程扑技覆术追、绞工其艺杏。象通沫常汉还蜂包忧括椒以洽主袜梁偶、租次兵梁遇、饱杆受件朱，屯板谎等方形魔式樱存读在蝶的街钢慈的燕热对轧巧加趁工津工薄艺秋。打上取个亡世瞎纪映七勇十馒年黑代受，绘除打了娇对放其塌他沾材渗料献的析需唉求德在耀增翁长悔，呀钢掀结置构窄仍鹅然丛保全持乐着馆对迎于夕来辽自红美此国园、拜英席国偿、欠日爹本牺、撇西站德聋、绒法葵国运等杏国槐家岔的足钢须材庄厂测钢丢材好的德大设量递需鼓求久。墨发量展赤历科史渠：奶早霞在腾B讨e鞭s谈s艺e地m庭e惰r疤和水S澡i秧e俊m三e戏n之s迅-甩M汁a膊r筋t遍o许n败(站开兼放巾式好炉缩)胸工雪艺华出详现识以坏前约，限钢秃结奸构棵就河已泳经静有粥几匀十闷年展的经历伐史盖了疏。迅而障直洞到忘此汇工纸艺衫问稳世声之缠后舞才吵使参得锦钢瓦材慈可多以经大咏批密生仆产忧出勺来砖供外结撒构追所椅用匪。睛对模钢场结讽构队诸档多尽问拔题削的料研素究决开诊始缸于掌铁零结胞构携的软使温用肆，窃当叔时灿很膏著殿名葛的闪研瑞究窑对惕象跟是晒1志9甜7雀7晴年屠在灿英杜国碰建惜造袋的棚横粉跨控斯播沃扔河辽的奉C肆o梯a所l爸b辈r格o倒o愿k蕉奇d答a幻l扑e守驶大拒桥碗。园这勇座殿大问桥呼以孩及猪后攻来部的机铁潮桥约设锦计呜再套加血上遭蒸翠汽问锅仙炉轻、背铁龟船铃身篮的矛设愤计稿都只刺狗激隔了谋建魂筑捕安阶装宵设言计杜以暑及置连省接缓工但艺塘的花发塑展正。妄铁联结团构柱对水材江料示的玻需挺求扮量问较怜小竹是组优好胜巧于粱砖藏石异结闪构聪的织主乖要纷方迫面磨。秆长丢久誉以嘉来缸一雅直狐用免木妥材份制帆作评的湖三蔬角震桁迹架胶也友换哥成铅铁搅制串的舱了窑。创承欧受女由沟直杰接巷荷漂载社产窑生零的列重也力暴作布用男的喜受无压貌构堵件猴常奥用石铸苗铁扯制鱼造泛，键而忍承钱受再由絮悬逃挂朵荷墓载鞠产商生绘的怜推好力聪作蹈用潮的物受自拉伪构码件链常饶用板熟迅铁盖制健造祸。茧把诱铁理加点热嗓到片塑卖性肤状美态衬，老使金之贵从析卷筐状激转张化占为犬扁膛平炸状输与揪圆最状贸之高间肚的激某掌一岭状辆态挂的离工想艺浪，忘早愁在渡1环8疲0绩0寻年只就俊得者以宽发堪展矛了捕。纽随谅后券，扁1状8著1训9普年耗角附钢设问捧世半，恭1铃8弊9拾4化年助第荡一命个初工薪字蚁钢捉被吴建孝造衡出晌来固作堡为善巴蔬黎叫火版车薄站臭的锦顶掩梁讨。讯此朗工衣字锅钢敞长坏1寸7治.劝7头英描尺贵）较（扒5浮.接4站米云）妹。剂1洽8柱5枪1奇年碗英呜国忽的锡J亦o艳s队e口p策h尼在P笨a尺x屈t膜o础n贞d孔为致伦蓬敦擦博纺览三会略建茄造双了及水貌晶广宫建。济据韵说未当踏时膛他四已巾有滥这骄样哀的聋骨胖架罗结石构躁构体思筝：摆用届比漫较傍细术的尚铁卷梁改作渣为构玻盲璃棒幕率墙申的婚骨弯架冰。关此过建餐筑愚的床风虎荷炮载靠抵过抗蕉力你是汽由虫对杰角让拉发杆蜓所仔提据供总的监。您在扎金毛属普结呆构持的浑发蓄展萌历残史稼中量，胖有波两头个版标债志撑性尼事殃件宜：雅首征先城是压从旧木惹桥精发站展驾而诱来售的纷格掠构顿梁李由轰木拜制却转厘化耀为的铁弊制择；堂其衫次志是圣锻仅铁屠制劳的效受沿拉慨构闷件现与体铸肺铁抽制览的滨受测压医构乘件最受诸热扯后凑通迷过吃铆臣钉疏连根接疯工妖艺盛的写发座展馋。允十绞九刺世森纪著五钟六谁十脑年光代朗，顿B赞e底s撕s衔e葬m始e缓r凯和与报礼S袭i献e滩m党e传n甜s睛-规M织a问r毯t淘i瞒n怜工挠艺活的那发丝展浪使事钢取材寿的喘生烦产阀能谦满朋足酿结绒构致的稼需盘求惧。尸钢篮的森受抹拉辞强贼度势与薄受哄压督强郊度舱都磁好裂于永铁梳。繁这垫种拌新瓜型默的老金桑属阅常坟被哈有绵想牛象谢力雄的陆工莫程贯师扇所渠利差用死，施尤效其挑倍惜受规那茶些矮参挤与零过上英钻国承、维欧软洲源以宫及休美宗国隐的皇道愿桥慨建差设丹的石工沈程舞师密的谢喜科爱稳。德其饿中厉一肆个寸很餐好切的覆例棒子则就烧是胀E则a延d退s敞大污桥鲜（柜也拐被酒称网为事路搞易绸斯挠洲疑大剥桥朗）尺（娇1斤8援6辩7变-拣1痒8瓶7洽4倡）佩。铃在议这经座金大呀桥秋中撞，野每剃隔押5毅0呼0办英赵尺昂（飘1销5贷2恢.殊5泊米鸭）腰设核有车由留钢拳管礼加乱强拘肋叙形煤成检的径拱丛。独英灾国窄的伯F凝i养r且t皂h撞此o龙f沫途F皇o损r心t刚h织悬现索谜桥雀设倡有脱管仅件逃支显撑是，棚直最径坐大必约绍为耐1去2幕英送尺槐（烘3薯.碧6伪6际米狭）玩，石长划度动为莲3什5式0搂英上尺过（屡1仰0季7奥）姜米静。槽这驼些吴大顽桥柏以药及吊其语他淘结甲构秘在壮引锹导封钢垫结晌构赖的糠发误展栽，宗规承范殿的犬实岩施欲，耕许恶用勺应筒力慢的至设升计捆方泳面果起替到会了俗很蒸重剖要娇的冠作罚用去。咽1促9振0崭7携年篮Q纵u靠e耗b咱e咏c雁悬千索康大蝶桥表的裂偶包然快破班坏掉揭涨露届了乞二传十枯世遍纪迟初盆期有由煤于棕缺梦乏内足册够推的罪理佳论永知汉识剑，腊甚梳至壤是衫缺狱乏坑足个够喝的物理斯论荡研苦究次的汉基耻础闭知革识号，艘而叮导牌致椒在伯应虾力敬分尾析芦方渐面婚出教现艳了院很候多淘的厦不束足圆。柏但歼是建，蝇这母样完的饲损货坏泰却瓣很近少窗出挡现泰在精金宰属悉骨别架乘的裹办蚊公跳大惊楼剖中遮。酷因悦为兆尽善管韵在争缺和乏该缜舱密尸的刃分颂析锄的甘情享况论下甲，润这凤些鉴建绣筑绢也奔表麻现爸出弯了裳很乓高润的杆实眨用兵性氏。猫在江上掠个格世柄纪抗中分叶达，疫没寺有碧经谅过父任步何旨特提殊根合渣金轮强川化菌、请硬宁化奋过密的汪普圣通抖碳逃素慢钢渔已赚经据被陶广乏泛时地伙使葡用摔了丈。证在序1辟8快8往9名年炒巴隔黎挖召跃开浴的焦世杨界洗博宵览彩会裤上野，知金饰属陶结催构吃表足现千出划了弃在致超挽高舟层酱建戒筑驳运窃用付上勾的热内辉在商潜怠力染。宰在涛这肃次滩会疲上铅，幼法勤国驴著弦名题的岔桥引梁剧设采计直师咬埃由非对尔凑展漫示勉了外他过的勇杰查作裤-酒3庭0气0坐米家高准的巷露态天肠开咽挖猎的仪铁乱塔义。洽无叨论佛是无它搭的趋高肢度粒（盐比笔著办名郊的那金霜字乞塔裳的粱两留倍猫还概高压）饰，盲架著设邀的贝速猴度引-扩人塞数处不尖多饶的箩工赚作迹人叉员互仅安用兴几啄个棵月摧的毒时踩间症就屑完系成炕了享整贫个阔工李程博任寨务柱，唉还判是订很踢低影的乎工美程响造六价卫都贝使碑它低脱泽颖表而沟出歪。瞧首败批跌摩亮天扑大朱厦汁：截在掘刚狠结僻构贞发糊展食的衰同洪时帮，晃美宏国骑的浑另连一颤个愉是赴也陶蓬怠勃壤的述发慕展捡起论来饰了构。歌1助8您8退4弦-萌1准8坦8遍5腔年俘，率芝袄加那哥刘的拒工暂程何师墙M慰a蝇j塞.钻W庭i正l怎l谣i粘a杠m剃板L面e罩急B辆a筛r渠o芽n蓬羽J馆e树n早n哭n易y胜设血计券了盗家载庭指保誓险浸公角司魂大倘厦心。砍这期座判大解厦物也葱是瞧金妹属鹊结足构唯的致，慕有森十束层肌高顽。助大揉厦阀的读梁壁是遍钢期制竟的必，凡而亭柱琴是拥铸亚铁扭所词制猜。迷铸研铁牙制堤的蹄过求梁课支坐撑卧着非窗寨洞轨口谦上荷方箭的难砌凝体闸，轧同榜时惠也臂需辰要责铸宾铁矿制义的浴柱梦支防撑桌着涛。庸实婶心罗砌阶体隙的神天旁井编与挎界带墙嘴提目供们抵盲抗茧风艺载朵的柳侧帝向盒支歇撑瓦。钩不愈到宽十蜂年责的倾功兄夫训，悠芝青加参哥牙和浓纽社约峰已存经匠有泉超地过蕉3蕉0迎座错办煤公寻大邀楼稿是冬利绳用怖这蚀种不结捷构角。计钢遵材苗在懒这仓些提结蛙构昏中彩起摆了邀非灿常依大治的圾作瘦用睛。内这惊种贺结妖构语利勤用鞭铆蒸钉岭把肿梁稠与顺柱拾连众接沾在现一聚起蛇。猜有功时巾为津了跳抵逃抗乱风奥荷望载愈还订是事在顷竖避向伸构蒜件推和驼横嚷向江构斑件救的刻连糟接校点阅出妨贴羞覆扁上烈节碎点画板敏来绩加礼固访结猪构偷。灯此姨外适，纱轻娇型忽的瑞玻鞋璃牙幕讲墙尖结赢构绸代卵替浸了狸老临式滋的佣重章质每砌劝体允结婆构朴。肃尽赏管画几旋十密年青来蚀之登中栋建佛筑丽形院式芽主数要译是巨在火美滋国汗发照展禁的俘，网但汇是厕它拍却霞影顺响厌着铅全窑世扰界脸钢州材眯工约业示的伍发矩展倘。膊十斗九洋世丑纪炕的户最哀后熔几晶年凉，免基旺本被结支构售形耳状籍工炉字数型呆钢瘦的括厚滩度镰已抵经唐达氧到淋2渣0丛英屑寸拦（安0填.溜5桂0途8回米胜）步，珠非需对赛称贝的晕Z占字摸型松钢膜和津T灵型章钢咳可描以是与尊有脊一华定远宽摧度诉和号厚蒜度竟的桑板愚相练联疯结帜，烛使请得诊构至件径具舞体泄符卵合觉要竹求浊的孩尺辟寸然和萝强尊度软。防1倦8例8近5村年快最按重烧的俯型矩钢幸通走过换热屠轧缺生炉产助出谎来芳，权每另英掉寸忌不谦到乐1输0荒0涨磅骄（榨4捆5关千橡克帐）脏。什到赚二钱十炎世触纪降六芽十玉年芬代呜这季个泥数钻字守已奴经腊达盲到暗每植英哨寸羡7宾0诉0睛磅座（问3盟2照0推千悠克壶）格。武紧弓随罢着迁钢辉结覆构香的冬发届展诚，贵1定9斜8萝8热年至第调一皱部慈电历梯称问裕世述了刑。磨安露全被载晌客赤电史梯哪诞孙生愧，洗以刷及击安昂全坚经失济破的袍钢孙结乒构溪设疯计碰方识法资的漫发翅展虽促山使鸦建燃筑份高旋度叶迅篇猛庙增错加株。伐1补9莫0拣2耀年间在乡纽苗约弯建猫造吗的唐高败2久8欺6获英话寸电（凭8罩7呜.绪2狱米案）幅的设F托l娃a祸t获i丘r周o够n踏大桑厦薄不族断抽地晕被呈后冲来腿的爽建立筑光所鹅超家越汁。笨这种些宵建乌筑棕分氧别宣是溉高坐3拔7疾5紧英叛尺孙（扭1走1焰5穷米带）木的皮时牲代龙大叶厦百（任1拜9紫0虑4敬）燃，挠（辈后兼来惧改磨名量为弊联捷合次化激工雅制砌品税大育厦庸）单。袖1掀9诉0错8地年吧在茶华惊尔耍街盼建柄造颠的鸦高殖4阀6爱8馅英过尺气（茄1魄4想3嫁米狡）铲的诚城雀市界投酬资踩公祝司洲大它厦翁，疗高责6报1狮2民蚂英扫尺换（积1毁8忍7饿米务）锤的树星浪尔建大固厦熄，窜以巨及撕7霸0帝0忽英两尺猛（挽2坡1归4固米绸）贼的盏都展市避塔闷和肉7卸8赠0各英墨尺锐高障（瓦2头3涂2终米火）农的内W殿o尿l圈l导横w灵o胖r容t鸭h南大灵厦洽。巩房青屋明高欠度拾与径高驶宽搭比蒜的池不森断寿增更加垮也贼带厘来雾了游许蜡多写的亡问沫题伸。赏为王了帐控槐制揭道搅路彩的远阻毁塞府，窑要野对漂建画筑沸的虾缩宇进珍设恐计蔽进症行宅限渗定衬。刃侧悲向鼻支务撑红的旧设怖置沙也羡是财其副中要一蜡项捕技雷术矿问煮题猾，颠例暴如消，柳埃郊非狐尔潮铁仁塔于所疯采层用求的怨对牲角骂支色撑织体疾系纠对顺于日要墓靠齿太泄阳血光柜来馅照彼明庭的宅办踢公路大吗厦岂就描不劳实烈用草了艰。介而桌只否有熄考琴虑菊到攀具栗体始的富单政独隐梁鲁与投单弊独镜柱海的米抗吨弯碧能痛力春以素及况梁漆柱闷相蹦交严处闪的愿刚顶度值的军框厚架枪设衫计久才贸是济可涉靠龙的伙。全随趣着遇现亚代连内雾部质采财光晌体眉系抚的剖不痰断爸发己展吵，革抵层抗奋风去荷寄载致的惑对否角简支未撑仗又君重芦新我被章利栋用孩起偏来傍了恶。迷芝朋加桐哥枪的诊J携o哀h议n搬占H逆a妹n第c来o趋c狂k记途中筹心霜就逆是拘一饺个腊很弄显娘著必的幼例家子正。偿外录部毯的毫对钥角抓支捏撑南成梦为病此真结环构骆立闸面傻的诉一餐个枪很例显底眼阁的龟部劣分翁。兔第朱一古次哈世违界蜓大年战必暂宇时默中亲断偶了钳所酒谓否摩此天疏大淘厦车（政当秤时金这雄个常词蔑并阶没避有赵确造定翅）码的唤蓬县勃萄发扎展驼，净但丰是葡二泻十询世齿纪佣二女十沿年皱代症又隶恢傲复羞了抄这泳一始趋检势泪。学1根9皆3俊1穗年抚建捆造栏的巷帝警国膊大肾厦园把龙词为潮惑流双推乔向柿了死顶马峰喇。迫1肌0视2污层寻高弓1本2仁5松0测英致尺熄（处3钢8米1号米辣）雾的勇帝委国引大享厦莲在勾后脾来笋的道4笼0乱年深一箭直究保奔持饶着灭世消界校最蜻高目的臣地尊位胜。肥它脉的沫建去造黄速签度鬼充抹分滩证肃明参了岭这驳种荒新脾的大结议构条形虫式溪已说经欲被币当亏时万的雁技版术控所刻掌愤握完。瞧次康项牧工隙程炕所认需豪要愈的篮梁债是帽由盼B丈a良y到o际n挥n或e鞠海颈湾季对纠岸珠的跳军束械境库歪所干提莫供楚的式。寺是侨由降用盘精甜密积仪滔器伪控糟制雷的畜驳住船殃和弦卡稿车瞎负厘责口运刮输豆的销。疤由拒九第架患起某重糕机梁将盏这凶些喝梁活提连升由到芬指驼定稻的敢位国置剧。推由虫工叙业融轨生道蛮装义置蒜把壁钢品材胜和喘其边他闪材羽料转移智到肿每思一节层灿上株去纳。复先窝是馆螺代栓品连弃接缩紧春接燕着锐铆咬钉构连千接雷，夫最汇后宅是庭装役修苗，路整宫个剖工役程取的耕最脉终欣完府成脸只血用竹了开一先年侦零颤4军5卫天洞。遍二愈十唇世可纪灿三带十秃年央代洒席声卷爽全兽世貌界脏的飞大蝶萧筐条纱以壮及建第名而刮次纯世情界傲大亏战会使找钢概结让构坑的继发纪展辫又塑一燥次座受饿到织了辫阻问碍怀。侵但闹是垂与田此差同叼时例，导焊私接负代瓦替爬了雕铆着钉罩连芹接眼则做是项一封个侄很日重般要扑的猾发荒展笨。生十闹九挥世洋纪乱末樱，鬼利呀用重焊姨接归把砖各剩个冲钢楼零源件蹈相涂连娃接皮已凤取优得塔了燥很饺好膀的贿成陵绩咸，帝并销在好第观一陡次哲世影界侧大崖战膊中捡被榨运截用吩于份救病生科船懂的净修在理叶。昨但泄直铲到鹊第拿二容次畅世番界足大灯战迷后话才休用渐于符建第筑踩结落构逝中耀。辨同厘时以在余连颠接继领艇域巩中筐又骑一发进百步仔就倘是余高施强榨螺伐栓茂代岁替飘了旺铆各钉糟。即二铺战拼结蔬束辞后岛，啦欧绍洲暂，爪美旗国联，丝日幸本步等稼国凯都联扩耕大堪了起对担在桂不亮定苦应幅力里（症包融括济超湾过恳屈波服傲点挽的张情每况盛）悄作图用通下臭各葡种托结隆构聪钢尚的鬼性受质过的拌研骂究法，男并台进照行礼了睁更递为宪精离确斧、户系振统行的械分欲析盼。童此徒后白，萌许每多懂国门家控采那用黄了坊一糖些奋更稠为马自友由宁灵亏活贩的列设没计沫规算范软和兔更蔑为杯理著想纳化醒的筐弹辩性膊设戚计肢规炊范伐。组计响算揪机念在炉工冷程止上方的仆运柏用默代可替购了突冗雕长陪的流手肌工走计太算吧，考从粘而粗更废加白促映进斜了饭钢开结帽构蓬的仪发店展兼，辨并长大紫大柿的俱减霉低鸭了贸造浪价东。损T过a阔l膀l肚i马n葬g本彼b酿u懂i馒l恰d混i雅n庸g衰救a听n劝d初柜S锤t喉e璃e乌l栏恼c旱o倘n费s兵t淘r乒u暂c粉t康i游o尾n彻A丢l吗t缺h富o大u俩g防h仓陈t订h闹e惹r弃e干电h抽a捞v文e吓序b稠e肌e孙n脊堡m裂a堵n始y裕蔑a恋d捕v粱a评n廉c旅e宿m扑e半n总t助s发蹄i泽n傻恭b板u搜i角l旷d磁i牧n雹g覆绕c月o辉n岩s嫁t礼r木u赵c仿t床i鸦o沈n昌倒t裁e果c泰h钢n详o弓l删o挑g投y辫霸i悉n塑野g龄e上n寻e立r勤a何l摘.被魔S拔p姨e差c窃t哀a结c那u闹l鼠a陈r李贵a光r吧c召h览i脸e呜v显e笨m辈e堵n歪t脑s捕嘱h盘a哄v雷e壮家b摄e吩e促n傅晕m腰a清d养e遭端i落n理江t总h迎e羡够d祥e慰s日i酸g堪n榜贷a页n伟d怜沙c片o虹n过s决t顽r矩u绳c惯t醒i辩o葵n挎骑o伞f歼狼u沈l答t倚r父a携h霸i她g哭h勿-淋r刚i称s士e是喇b爸u若i律l梦d乓i盏n去g重s铸.途T斗h宫e墨捷e提a点r匠l叔y践扫d烛e碑v航e蝴l汁o绣p腿m属e贞n素t顿新o派f仇桂h盖i纱g朗h你-嫁r窄i嚷s毒e恳较b万u粱i幸l区d门i障n助g合s秤猴b对e偏g占a指n衬眉w淹i贼t介h词烟s误t献r乞u遇c响t仇u烈r颜a章l星懒s顷t冈e诵e印l括栗f梁r乘a解m语i电n慎g础.洲R悲e野i搬n歇f净o哄r询c习e脏d娃籍c喜o值n续c迹r夺e银t营e够距a估n雷d岂条s陕t尘r且e面s表s这e主d蓬-葡s怜k里i绕n猪捧t艰u纤b黄e圆誉s爽y秆s雹t馆e蛮m卡s违猾h问a绸v和e槽贝s役i桃n姨c阔e桑司b舰e活e帐n牧效e软c逗o顾n奋o恢m跳i适c业a远l塞l宜y蓝糖a薯n敢d逝赛c答o尚m芬p视e绸t港i丢t平i抢v努e梳l趁y答锐u对s苍e骗d常档i浙n岁离a洲臂n确u犁m碌b询e害r搁匠o侄f跟项s卖t乖r毙u看c勾t杂u旷r竿e刘s治咬f碍o蝇r裁滋b迹o窑t写h过荒r所e乓s衔i腊d缠e筋n丈t放i赶a底l偿次a皱n望d获醋c液o唤m毯m银e汁r剃c喊i何a筒l救炮p睬u储r克p爷o鼓s院e独s亦.蝇T者h雨e丛献h筹i轮g支h镜-剧r词i统s荡e瓶润b情u蝇i黎l堆d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rimeterspandrelbeamsisalsoreduced,andtheneedforupsetbeamsabovefloors,whichwouldencroachonvaluablespace,isminimized.Thestructuralsystemhasbeenusedonthe54-storyOneMellonBankCenterinPittburgh.Systemsinconcrete.Whiletallbuildingsconstructedofsteelhadanearlystart,developmentoftallbuildingsofreinforcedconcreteprogressedatafastenoughratetoprovideacompetitivechanllengetostructuralsteelsystemsforbothofficeandapartmentbuildings.Framedtube.Asdiscussedabove,thefirstframedtubeconceptfortallbuildingswasusedforthe43-storyDeWittChestnutApartmentBuilding.Inthisbuilding,exteriorcolumnswerespacedat5.5ft(1.68m)centers,andinteriorcolumnswereusedasneededtosupportthe8-in.-thick(20-m)flat-plateconcreteslabs.Tubeintube.Anothersysteminreinforcedconcreteforofficebuildingscombinesthetraditionalshearwallconstructionwithanexteriorframedtube.Thesystemconsistsofanouterframedtubeofverycloselyspacedcolumnsandaninteriorrigidshearwalltubeenclosingthecentralservicearea.Thesystem(Fig.2),knownasthetube-in-tubesystem,madeitpossibletodesigntheworld’spresenttallest(714ftor218m)lightweightconcretebuilding(the52-storyOneShellPlazaBuildinginHouston)fortheunitpriceofatraditionalshearwallstructureofonly35stories.Systemscombiningbothconcreteandsteelhavealsobeendeveloped,anexamleofwhichisthecompositesystemdevelopedbyskidmore,Owings&Merrilinwhichanexteriorcloselyspacedframedtubeinconcreteenvelopsaninteriorsteelframing,therebycombiningtheadvantagesofbothreinforcedconcreteandstructuralsteelsystems.The52-storyOneShellSquareBuildinginNewOrleansisbasedonthissystem.Steelconstructionreferstoabroadrangeofbuildingconstructioninwhichsteelplaystheleadingrole.Moststeelconstructionconsistsoflarge-scalebuildingsorengineeringworks,withthesteelgenerallyintheformofbeams,girders,bars,plates,andothermembersshapedthroughthehot-rolledprocess.Despitetheincreaseduseofothermaterials,steelconstructionremainedamajoroutletforthesteelindustriesoftheU.S,U.K,U.S.S.R,Japan,WestGerman,France,andothersteelproducersinthe1970s.Earlyhistory.ThehistoryofsteelconstructionbeginsparadoxicallyseveraldecadesbeforetheintroductionoftheBessemerandtheSiemens-Martin(openj-hearth)processesmadeitpossibletoproducesteelinquantitiessufficientforstructureuse.Manyofproblemsofsteelconstructionwerestudiedearlierinconnectionwithironconstruction,whichbeganwiththeCoalbrookdaleBridge,builtincastironovertheSevernRiverinEnglandin1777.Thisandsubsequentironbridgework,inadditiontotheconstructionofsteamboilersandironshiphulls,spurredthedevelopmentoftechniquesforfabricating,designing,andjioning.Theadvantagesofironovermasonrylayinthemuchsmalleramountsofmaterialrequired.Thetrussform,basedontheresistanceofthetriangletodeformation,longusedintimber,wastranslatedeffectivelyintoiron,withcastironbeingusedforcompressionmembers-i.e,thosebearingtheweightofdirectloading-andwroughtironbeingusedfortensionmembers-i.e,thosebearingthepullofsuspendedloading.Thetechniqueforpassingiron,heatedtotheplasticstate,betweenrollstoformflatandroundedbars,wasdevelopedasearlyas1800;by1819angleironswererolled;andin1849thefirstIbeams,17.7feet(5.4m)long,werefabricatedasroofgirdersforaParisrailroadstation.TwoyearslaterJosephPaxtonofEnglandbuilttheCrystalPalacefortheLondonExpositionof1851.Heissaidtohaveconceivedtheideaofcageconstruction-usingrelativelyslenderironbeamsasaskeletonfortheglasswallsofalarge,openstructure.ResistancetowindforcesintheCrystalpalacewasprovidedbydiagonalironrods.Twofeatureareparticularlyimportantinthehistoryofmetalconstruction;first,theuseoflatticedgirder,whicharesmalltrusses,aformfirstdevelopedintimberbridgesandotherstructuresandtranslatedintometalbyPaxton;andsecond,thejoiningofwrought-irontensionmembersandcast-ironcompressionmembersbymeansofrivetsinsertedwhilehot.In1853thefirstmetalfloorbeamswererolledfortheCooperUnionBuildinginNewYork.Inthelightoftheprincipalmarketdemandforironbeamsatthetime,itisnotsurprisingthattheCooperUnionbeamscloselyresembledrailroadrails.ThedevelopmentoftheBessemerandSiemens-Martinprocessesinthe1850sand1860ssuddenlyopenthewaytotheuseofsteelforstructuralpurpose.Strongerthanironinbothtensionandcompression,thenewlyavailablemetalwasseizedonbyimaginativeengineers,notablybythoseinvolvedinbuildingthegreatnumberofheavyrailroadbridgesthenindemandinBritain,Europe,andtheU.S.AnotableexamplewastheEadsBridge,alsoknownastheSt.LouisBridge,inSt.Louis(1867-1874),inwhichtubularsteelribswereusedtoformarcheswithaspanofmorethan500ft(152.5m).InBritain,theFirthofForthcantileverbridge(1883-90)employedtubularstruts,some12ft(3.66m)indiameterand350ft(107m)long.Suchbridgesandotherstructureswereimportantinleadingtothedevelopmentandenforcementofstandardsandcodificationofpermissibledesignstresses.Thelackofadequatetheoreticalknowledge,andevenofanadequatebasisfortheoreticalstudies,limitedthevalueofstressanalysisduringtheearlyyearsofthe20thcentury,asiccasionallyfailures,suchasthatofacantileverbridgeinQuebecin1907,revealed.Butfailureswererareinthemetal-skeletonofficebuildings;thesimplicityoftheirdesignprovedhighlypracticalevenintheabsenceofsophisticatedanalysistechniques.Throughoutthefirstthirdofthecentury,ordinarycarbonsteel,withoutanyspecialalloystrengtheningorhardening,wasuniversallyused.Thepossibilitiesinherentinmetalconstructionforhigh-risebuildingwasdemonstratedtotheworldbytheParisExpositionof1889.forwhichAlexandre-GustaveEiffel,aleadingFrenchbridgeengineer,erectedanopenworkmetaltower300m(984ft)high.Notonlywastheheight-morethandoublethatoftheGreatPyramid-remarkable,butthespeedoferectionandlowcostwereevenmoreso,asmallcrewcompletedtheworkinafewmonths.Thefirstskyscrapers.Meantime,intheUnitedStatesanotherimportantdevelopmentwastakingplace.In1884-85Maj.WilliamLeBaronJenney,aChicagoengineer,haddesignedtheHomeInsuranceBuilding,tenstorieshigh,withametalskeleton.Jenney’sbeamswereofBessemersteel,thoughhiscolumnswerecastiron.Castironlintelssupportingmasonryoverwindowopeningswere,inturn,supportedonthecastironcolumns.Soildmasonrycourtandpartywallsprovidedlateralsupportagainstwindloading.Withinadecadethesametypeofconstructionhadbeenusedinmorethan30officebuildingsinChicagoandNewYork.Steelplayedalargerandlargerroleinthese,withrivetedconnectionsforbeamsandcolumns,sometimesstrengthenedforwindbracingbyoverlayinggussetplatesatthejunctionofverticalandhorizontalmembers.Lightmasonrycurtainwalls,supportedateachfloorlevel,replacedtheoldheavymasonrycurtainwalls,supportedateachfloorlevel,replacedtheoldheavymasonry.ThoughthenewconstructionformwastoremaincentredalmostentirelyinAmericaforseveraldecade,itsimpactonthesteelindustrywasworldwide.Bythelastyearsofthe19thcentury,thebasicstructuralshapes-Ibeamsupto20in.(0.508m)indepthandZandTshapesoflesserproportionswerereadilyavailable,tocombinewithplatesofseveralwidthsandthicknessestomakeefficientmembersofanyrequiredsizeandstrength.In1885theheavieststructuralshapeproducedthroughhot-rollingweighedlessthan100pounds(45kilograms)perfoot;decadebydecadethisfigureroseuntilinthe1960sitexceeded700pounds(320kilograms)perfoot.CoincidentwiththeintroductionofstructuralsteelcametheintroductionoftheOtiselectricelevatorin1889.Thedemonstrationofasafepassengerelevator,togetherwiththatofasafeandeconomicalsteelconstructionmethod,sentbuildingheightssoaring.InNewYorkthe286-ft(87.2-m)FlatironBuildingof1902wassurpassedin1904bythe375-ft(115-m)TimesBuilding(renamedtheAlliedChemicalBuilding),the468-ft(143-m)CityInvestingCompanyBuildinginWallStreet,the612-ft(187-m)SingerBuilding(1908),the700-ft(214-m)MetropolitanTower(1909)and,in1913,the780-ft(232-m)WoolworthBuilding.Therapidincreaseinheightandtheheight-to-widthratiobroughtproblems.Tolimitstreetcongestion,buildingsetbackdesignwasprescribed.