【正文】 The analysis of the structural collapse of the building was performed in two stages．The first part of the analysis consisted of the simulation of the explosion itself from the detonation instant and the second part consisted of the analysis of the effect and interaction with the building of the blast wave generated by the explosion．Only the load produced by the air blast wave was considered in the analysis．The ground motion generated by the explosion was not taken into account． ig．2 shows the numerical results of the collapsed building．The parison of numerical results with photographs taken after the terrorist attack showed that the numerical analysis accurately reproduced the collapse of the building under the blast load．The good agreement between actual damage and that one numerically obtained proves that the detailed simulation of the structure，materials and blast effects are needed for this type of analysis and nowadays represent the only way to successfully run a plete collapse analysis of an entire building．在這段忙碌又充實(shí)的日子里，我學(xué)到了很多以前沒有學(xué)到的知識，也遇到了許多以往所沒經(jīng)歷的事情，使我受益良多。在結(jié)構(gòu)設(shè)計(jì)中，根據(jù)《荷載規(guī)范》，正確計(jì)算作用框架上的荷載值；掌握了框架結(jié)構(gòu)的內(nèi)力分析方法，學(xué)會了內(nèi)力組合；根據(jù)控制截面的不利內(nèi)力值和截面的尺寸進(jìn)行配筋和節(jié)點(diǎn)構(gòu)造設(shè)計(jì)。⑥箍筋加密區(qū)長度底層柱根部取2000mm，其他端部取為1000mm。④柱計(jì)算長度l0=。全部梁的斜截面配筋計(jì)算結(jié)果與結(jié)果見下表?？紤]抗震承載力調(diào)整系數(shù)，=?m。當(dāng)梁上部受拉時(shí)，按矩形截面設(shè)計(jì)。177。177。177。177。177。177。177。177。177。177。0177。177。177。177。177。177。177。20四層12345177。177。由于對稱性，每層有5各控制截面，即圖339所示，梁中的1，2，3，4，5截面。m） 風(fēng)荷載作用下內(nèi)力計(jì)算風(fēng)荷載作用下的結(jié)構(gòu)計(jì)算簡圖如圖24，內(nèi)力計(jì)算采用D值法，計(jì)算過程見圖226所示，其中由建筑結(jié)構(gòu)抗震中附表69，610查的，即，由以前計(jì)算可知，風(fēng)荷載分布較接近均布荷載，從而得出下列計(jì)算過程和圖 圖325 剪力在各柱間的分配(kN) 圖326 各柱反彎點(diǎn)及柱端彎矩()表39梁端彎矩M5AB=M5BA=M5BC=M4AB=M4BA=M4BC=M3AB=M3BA=M3BC=M2AB=M2BA=M2BC=M1AB=M1BA=M1BC=圖327 風(fēng)荷載作用下框架彎矩圖單位（kNm） 活載荷載作用下的內(nèi)力計(jì)算活載作用下的內(nèi)力計(jì)算采用滿布荷載法，把活荷載同時(shí)作用于所有活荷載作用下頂層彎矩計(jì)算：，圖316 活載作用下頂層彎矩計(jì)算 單位（kN結(jié)構(gòu)內(nèi)力可用彎矩分配法計(jì)算并利用結(jié)構(gòu)對稱性取1/2結(jié)構(gòu)計(jì)算下表為節(jié)點(diǎn)分配系數(shù)計(jì)算，且上層柱的分配傳遞系數(shù)為1/3，圖27為頂層框架彎矩計(jì)算：表38 節(jié)點(diǎn)分配系數(shù)表層次相對線剛度相對線剛度總和分配系數(shù)左梁右梁上柱下柱左梁右梁上柱下柱頂層中間層底層圖37 頂層框架彎矩計(jì)算 單位（kN Z3 V43= kNZ4 V44= kN3層 Z1 V31= kN 。第3章 結(jié)構(gòu)設(shè)計(jì) 圖31結(jié)構(gòu)布置及計(jì)算簡圖 梁的截面尺寸主梁： l1=7200mm截面尺寸：h1=(1/8～1/12)l1=（600～900）mm，取h1=800mmb1=(1/～1/)h1=（320～533）mm，取b1=320mml2=6900mm截面尺寸：h1=(1/8～1/12)l1=（575～863）mm，取h1=600mmb1=(1/～1/)h1=（240～400）mm，取b1=300mm次梁： l3=7200mm截面尺寸：h3=(1/15～1/10)l2=（480～720）mm，取h3=600mmb3=(1/～1/)h2=（240～400）mm，取b3=300mm中間梁： l4=3000mm截面尺寸：h4=600mm b4=300mm 柱的截面尺寸房屋高度＜30m，由抗震規(guī)范可知，抗震等級為三級。框架結(jié)構(gòu)具有建筑平面布置靈活，室內(nèi)空間大等優(yōu)點(diǎn)，廣泛應(yīng)用于電子、輕工、食品、化工等多層廠房和教室、住宅、辦公、商業(yè)、旅館等民用建筑?？蚣芙Y(jié)構(gòu)具有建筑平面布置靈活，室內(nèi)空間大等優(yōu)點(diǎn)，因此這次設(shè)計(jì)的綜合教學(xué)樓采用鋼筋混凝土框架結(jié)構(gòu)。綜合性建筑往往受到房地產(chǎn)開發(fā)商的青睞，其原因主要在于各種功能部分能獨(dú)立出售或出租，利于回收投資。畢業(yè)設(shè)計(jì)的英文翻譯不僅讓我溫習(xí)了英語課程，還使我在查閱英文資料、撰寫英文翻譯的同時(shí)了解到更多的土木工程專業(yè)的新詞匯、新技術(shù)及新理念。結(jié)構(gòu)部分：先確定結(jié)構(gòu)方案，然后進(jìn)行結(jié)構(gòu)計(jì)算（截面假定及荷載計(jì)算，內(nèi)力計(jì)算，地震作用及內(nèi)力計(jì)算，風(fēng)荷載作用及內(nèi)力計(jì)算，內(nèi)力組合及截面配筋，現(xiàn)澆板等配筋計(jì)算）。室內(nèi)外高差為450mm。在房屋的縱向則設(shè)置連系梁與橫向框架連接，這些聯(lián)系梁與柱實(shí)際上形成了縱向框架，承受平行于房屋縱向的水平風(fēng)荷載和地震荷載。 Z2 V52=D52/D5= kNZ3 V53=D53/D5= kN 。 Z2 V12= kN 。m）圖312 恒載作用下底層彎矩計(jì)算結(jié)果圖單位（kNm）圖321 活載作用下底層彎矩圖 單位（kNm）圖334 中間層結(jié)構(gòu)在重力荷載代表值作用下的彎矩圖 單位（kN177。0177。177。177。177。二層12345177。177。177。177。177。177。177。177。177。177。177。177。177。177。梁的截面尺寸為320800，300600兩種，則h01=80035=765mm，h02=60035=565mm?？紤]抗震承載力調(diào)整系數(shù)γRE=，=?m。梁端箍筋加密區(qū)取2肢Φ8100，箍筋用HPB235級鋼筋（fyv =210N/mm2），則:，非加密區(qū)取2肢Φ8150設(shè)置滿足要求。表316柱剪跨比和軸壓比計(jì)算表樓層柱b(mm)h0(mm)Mc(kN?m)Vc(kN)N(kN)Mc/Vch0N/fcbh0五邊600560中600560四邊600560226中600560三邊600560中600560二邊600560中600560一邊650610中6506104．柱正截面承載力計(jì)算計(jì)算要點(diǎn)：①，當(dāng)ξ＜ξb時(shí)為大偏心受壓柱；當(dāng)ξ＞ξb時(shí)為小偏心受壓柱。③時(shí)截面滿足要求。建筑設(shè)計(jì)是對擬建建筑物預(yù)先進(jìn)行設(shè)想和規(guī)劃，根據(jù)建筑物的用途和要求確定其各部分的形狀和尺寸，并將各部分有機(jī)地組織到一起，創(chuàng)造出優(yōu)美協(xié)調(diào)的建筑空間環(huán)境。 由于自身所學(xué)知識的局限性以及第一次獨(dú)立的完成設(shè)計(jì)，設(shè)計(jì)中難免存在問題。The current available methods in analyzing structural progressive collapse could be classified into two major categories，namely the direct simulation method，in which the blast loading effects on structural damage and building collapse are directly simulated，and uncoupled alternative load path method with analysis of the structure by simulating various levels of damage by the removal of key load—carrying members．In the present paper，the available progressive collapse analysis methods in the literature are reviewed according to their categories．Both advantages and disadvantages of each method are listed．Their suitability，applicability and reliability are also discussed．Our recently proposed new method for progressive collapse analysis of reinforced concrete frames under blast 1oads is al so introduced．1. Progressive collapse analysis methods for building structures.The plete simulation consists of four stages：static equilibrium calculation to get the initial stresses and strains from gravity；simulation of a Boeing 767 airplane impacting the tower；the reduction of the strength and stiffness of the tower resulting from the postimpact fuel fire；and finally，the progressive collapse of the Tower driven by gravity．Fig．4 gives one of the typical results，which presents the material location of the tower at 6．5 s after the impact．As can be seen，the building had already collapsed to half of its height．The numerical results showed that a scientifically substantiated plausible scenario for the impact and collapse event of the North Tower could be obtained through the numerical simulation．In the progressive analysis，a r