1、文獻(xiàn)翻譯對(duì)于結(jié)構(gòu)理論與設(shè)計(jì)的分析近年來(lái),我國(guó)正在從橋梁工程建設(shè)大國(guó)向橋國(guó)邁進(jìn).與此同時(shí),大規(guī)模的橋梁工程建設(shè)也帶來(lái)了不可忽視的環(huán)境問題.當(dāng)前,可持續(xù)發(fā)展已成為國(guó)際結(jié)構(gòu)工程領(lǐng)域的共同理念,環(huán)境與經(jīng)濟(jì)的協(xié)調(diào)發(fā)展是促進(jìn)橋梁工程可持續(xù)發(fā)展的重要問題,在分析橋梁工程建設(shè)帶來(lái)的環(huán)境問題的同時(shí),橋梁工程生命周期環(huán)析也逐漸成為國(guó)內(nèi)外研究的熱點(diǎn).我國(guó)雖然在材料工業(yè)、生態(tài)產(chǎn)品等領(lǐng)域開展境影響成本分析研究,但對(duì)于橋梁工程生命成本的研究尚處于探索階段,因此,有必要對(duì)橋梁工程生命周期環(huán)境影響成本分析方法進(jìn)行系統(tǒng)的研究. 本文依托湖北省自然科學(xué)基金項(xiàng)目“橋梁工程生命周期環(huán)境影響評(píng)價(jià)方法研究”(2008CDB367),以武

2、漢市野芷湖大橋?yàn)閷?shí)際工程背景,以保護(hù)環(huán)境、降低橋梁工程生命周期環(huán)境影響成本為出發(fā)點(diǎn),基于生命周生命周期成本分析理論,進(jìn)行橋梁工程生命周期環(huán)境影響成本分析,構(gòu)建了橋梁工程生命周期環(huán)境影響成本分析模型,主要研究成果如下: 1、運(yùn)用生命周期評(píng)價(jià)和生命周期成本分析理論,基于橋梁工程生命周期環(huán)境影響因素的多樣性和復(fù)雜性,按照科學(xué)性、完整性等原則橋梁工程環(huán)境影響成本分為資源消耗成本、水污染成本.橋梁的結(jié)構(gòu)理論中對(duì)橋面鋪裝層的計(jì)算分析論述幾近于零,現(xiàn)行規(guī)范中只給定了厚度的推薦值,工程界一直在各等級(jí)的公路中運(yùn)用了幾十年。隨著交通量的增大,現(xiàn)行鋪裝與重型、超重型汽車的增多和車速的增快已不相適應(yīng)。橋面鋪裝層直接承

3、受車輪荷載的沖擊,橋面鋪裝部分或全部參與了主梁結(jié)構(gòu)的變形,因此橋面鋪裝是一個(gè)受力復(fù)雜的動(dòng)力體系,各種形式的主梁及鋪裝本身的構(gòu)造均影響其應(yīng)力的分布。現(xiàn)行橋規(guī)第3.2.2條規(guī)定:如無(wú)精確的計(jì)算方法,箱形梁也可參照T形梁的規(guī)定處理。從眾多箱梁的設(shè)計(jì)來(lái)看,大部分設(shè)計(jì)者對(duì)箱梁構(gòu)件是按T形梁進(jìn)行處理的。而箱梁的實(shí)際受力雖有近于T梁的一面,又有異于T梁的一面,對(duì)于連續(xù)箱梁差別更大。橋梁施工過程易發(fā)生安全事故的主要原因在于以下四個(gè)方面：其一，開挖基坑時(shí)由于護(hù)壁處理不到位，造成基坑坍塌，孔內(nèi)爆破未采用電引起爆施工，裸露藥包且沒有打眼放炮，在孔深大于12m時(shí)沒有檢測(cè)有毒氣體含量等；在清孔排水時(shí)未注意保持孔內(nèi)水頭而

4、造成內(nèi)外壓力差過大，從而導(dǎo)致護(hù)筒坍塌，井口周圍缺少圍護(hù)設(shè)施和安全標(biāo)示；其二，由于架橋設(shè)備或支架承載能力以及安全寬度不夠，導(dǎo)致墩柱施工過程中坍塌或墜落現(xiàn)象，構(gòu)建運(yùn)輸過程速度超過3km/h；其三，在需要放置安全網(wǎng)和防墜網(wǎng)的施工位置，沒有按照規(guī)定實(shí)行梁體制安，導(dǎo)致人員和機(jī)械設(shè)備墜落事故；最后，由于員工缺乏安全意識(shí)，出現(xiàn)未配備安保設(shè)備，不文明生產(chǎn)等現(xiàn)象，如10m以上作業(yè)時(shí)未加設(shè)安全網(wǎng)，導(dǎo)致附屬設(shè)施施工出現(xiàn)一系列安全事故。尤其是近年來(lái)箱梁的橋面越來(lái)越寬,橋跨與橋?qū)捴仍絹?lái)越小,箱梁仍按T梁那種長(zhǎng)細(xì)桿件設(shè)計(jì)配筋,就越來(lái)越不適宜了,導(dǎo)致按梁設(shè)計(jì)的箱骨架鋼筋在實(shí)際受力狀態(tài)下難以像T梁主筋那樣發(fā)揮應(yīng)有的作用。所

5、以,設(shè)計(jì)的假設(shè)狀態(tài)與箱梁的實(shí)際受力狀態(tài)不一致。采用取孔壁支護(hù)等措施防止挖孔較深時(shí)坍塌現(xiàn)象，配備專人定期檢查孔口防護(hù)設(shè)施是否完好，以及施工現(xiàn)場(chǎng)的作業(yè)設(shè)備和流程以及警示標(biāo)志是否規(guī)范到位；挖孔前檢測(cè)二氧化碳等氣體是否超標(biāo)，孔深超過10m時(shí)應(yīng)當(dāng)強(qiáng)制通風(fēng)。高處作業(yè)之前需進(jìn)行安全技術(shù)教育，檢查投入使用的設(shè)備是否完好，如未經(jīng)上級(jí)許可不得擅自拆除高處作業(yè)防護(hù)設(shè)施；高處施工人員需按規(guī)定著裝，穿軟底防滑鞋，系上安全帶，與架空輸電線路保持規(guī)定的安全距離，遇惡劣氣候不得進(jìn)行露天攀登或懸空高處作業(yè)；高處作業(yè)使用物料應(yīng)堆放平穩(wěn)，對(duì)于存在安全隱患的物件一律先行撤除或固定，存在人身安全時(shí)應(yīng)立即停止作業(yè)。隨著材料工業(yè)的發(fā)展,橋

6、梁承重結(jié)構(gòu)的改進(jìn),使橋梁主梁能以較柔的結(jié)構(gòu)達(dá)到受力的要求,高等級(jí)公路大跨橋梁的橫向越來(lái)越寬。無(wú)論是陸地橋梁還是海上橋梁基坑開挖時(shí)都需要根據(jù)相關(guān)規(guī)范先編制施工方案，提出設(shè)計(jì)計(jì)算書；采取安全防護(hù)如保持與挖掘機(jī)和吊斗升降作業(yè)安全距離范圍內(nèi)，檢查吊斗繩索、掛鉤等是否完好；拆除基坑支撐等作業(yè)需在負(fù)責(zé)人指導(dǎo)下進(jìn)行，海上橋梁施工安全管理與陸地施工相比主要不同在于存在更多的危險(xiǎn)性，因此安全管理工作應(yīng)該從創(chuàng)造施工安全的工作環(huán)境，保證設(shè)備設(shè)施齊全完好，及時(shí)準(zhǔn)確收集發(fā)布?xì)庀笏男畔⒑烷_展海上施工安全教育四個(gè)方面入手。具體說(shuō)來(lái)，應(yīng)盡量減少海上作業(yè)人員流動(dòng)的頻率，保證海上工作平臺(tái)和通道等安防設(shè)施齊全完好；掌握及時(shí)可靠的

7、氣象水文信息，盡量避免惡劣氣象和水文條件下作業(yè)；印發(fā)安全施工資料，組織開展安全系列教育工作，并進(jìn)行現(xiàn)場(chǎng)安全技術(shù)交底檢驗(yàn)；各個(gè)作業(yè)面加強(qiáng)日常現(xiàn)場(chǎng)安全檢查，嚴(yán)抓高處作業(yè)、大型構(gòu)件裝載等危險(xiǎn)系數(shù)大的關(guān)鍵工。由于山區(qū)地形復(fù)雜給橋梁施工帶來(lái)了很多不便，因此將安全人機(jī)工程技術(shù)融入施工安全管理中，有利于減少橋梁施工事故的發(fā)生幾率并保障施工安全順利進(jìn)行。山區(qū)橋梁施工安全管理主要從合理利用橋梁施工人員心理特征和防止過度疲勞入手，因?yàn)樵谏絽^(qū)橋梁施工工程中，人為不安全心理與環(huán)境條件限制產(chǎn)生的復(fù)合作用是主要不良因素，充分保證安全防護(hù)系統(tǒng)柔性防護(hù)系統(tǒng)的實(shí)施到位，加強(qiáng)不安全心理的綜合管理，以劃分若干個(gè)小群體針對(duì)性的培養(yǎng)安

8、全骨干，通過群體心理引導(dǎo)養(yǎng)成安全生產(chǎn)習(xí)慣，使得每位作業(yè)人員具備良好的心理狀態(tài)；合理安排作息時(shí)間，減輕施工勞動(dòng)強(qiáng)度，提高施工技術(shù)熟練程度的同時(shí)開展有益身心健康的文體活動(dòng)。公路橋梁施工受環(huán)境的限制和人為因素的復(fù)合影響，應(yīng)充分利用群體心理，通過培養(yǎng)安全骨干提高整體安全意識(shí)，養(yǎng)成安全生產(chǎn)的習(xí)慣；通過提高機(jī)械自動(dòng)化水平和員工技能，合理安排勞動(dòng)強(qiáng)度，杜絕過勞現(xiàn)象，對(duì)工作人員進(jìn)行定期部署有針對(duì)性的技能考核；采用不同的色彩標(biāo)志預(yù)防事故發(fā)生，堅(jiān)決淘汰高耗能，污染嚴(yán)重，技術(shù)改造不經(jīng)濟(jì)的設(shè)備，定期正確保養(yǎng)機(jī)械設(shè)備，特種設(shè)備需經(jīng)過安全檢測(cè)后才能投入使用。出現(xiàn)坑塌或洪水時(shí)應(yīng)當(dāng)及時(shí)采用加固措施并及時(shí)撤離現(xiàn)場(chǎng)。 特別在設(shè)計(jì)

9、計(jì)算中側(cè)重于主梁縱向的計(jì)算分析,對(duì)橋梁橫向剛度重視不足,橫向構(gòu)造措施不利使橋面鋪裝分擔(dān)了過多的次內(nèi)力。鋼筋加工的質(zhì)量問題存在于多個(gè)方面，在材料選擇方面，如果鋼筋品種的規(guī)格、形狀、尺寸不符合要求，或者鋼筋有嚴(yán)重的腐蝕問題，都會(huì)影響到工程質(zhì)量。在鋼筋加工方面，鋼筋的下料和成型尺寸的準(zhǔn)確度差、鋼筋骨架變形或者鋼盤網(wǎng)變形都會(huì)造成結(jié)構(gòu)構(gòu)件的性能下降；在鋼筋安裝方面，安裝位置偏差過大、鋼筋少放或漏放、墊塊位置固定方法不當(dāng)、鋼筋綁扎接頭不正確等都會(huì)引起鋼筋的嚴(yán)重錯(cuò)位；在鋼筋焊接方面，鋼筋焊接頭的機(jī)械性能達(dá)不到施工規(guī)范的要求、焊條品種存在質(zhì)量問題，性能不符合要求等都會(huì)存在問題。焊接過程中如果焊縫尺寸偏差過大、

10、咬邊焊縫與鋼筋交接處有缺口、咬邊焊縫與鋼筋交接處有缺口、電弧燒傷鋼筋表面等都會(huì)造成鋼筋斷面局部削弱，或?qū)︿摻町a(chǎn)生脆化作用，都會(huì)對(duì)鋼筋的使用性能造成影響。要對(duì)有可能出現(xiàn)斷樁情況的樁進(jìn)行重點(diǎn)監(jiān)測(cè)，對(duì)于進(jìn)行過故障處理的樁也要重點(diǎn)監(jiān)測(cè)，對(duì)于所有樁都要進(jìn)行無(wú)破壞檢測(cè)，使所有樁最終都要達(dá)到無(wú)斷層、無(wú)夾層，并且強(qiáng)度要符合設(shè)計(jì)要求。樁頭混凝土要鑿出密實(shí)的層面，并進(jìn)行大面平整，要求達(dá)到無(wú)殘留混凝土以及其他雜物，另外標(biāo)高必須符合施工設(shè)計(jì)要求。需嵌入承臺(tái)或系梁內(nèi)的樁頭及錨固鋼筋長(zhǎng)度要符合設(shè)計(jì)要求，在驗(yàn)收鋼筋時(shí)，要注意重點(diǎn)驗(yàn)收鋼筋骨架以及樁柱鋼筋的焊接質(zhì)量，樁頂錨固筋要與設(shè)計(jì)角度保持一致，并采用螺旋筋進(jìn)行纏繞固定。砂

11、漿墊層在平整度方面以及標(biāo)高方面要符合要求，其尺寸必須滿足支立承臺(tái)、系梁模板的要求，模板板面之間要求不漏漿、接縫嚴(yán)密、支撐牢靠，其各項(xiàng)指標(biāo)比如位置、幾何尺寸、保護(hù)層厚度等數(shù)據(jù)都要符合設(shè)計(jì)要求。在澆筑混凝土之前，應(yīng)該為模板涂刷脫模劑，外露面混凝土模板的脫模劑應(yīng)采用同一品種，在涂刷過程中不能污染鋼筋及混凝土的施工縫，這樣才能夠保證外露面美觀，線條流暢。對(duì)于連續(xù)梁橋、拱橋及懸臂梁橋等橋型結(jié)構(gòu),由于荷載的作用而產(chǎn)生負(fù)彎矩或拉力,使橋面鋪裝層受到拉力的作用而產(chǎn)生負(fù)彎矩區(qū)裂縫,從而造成橋面鋪裝的損壞。橋梁工程建設(shè)周期長(zhǎng)、投資規(guī)模大,施工過程為露天和高空作業(yè),是一項(xiàng)復(fù)雜的系統(tǒng)工作.橋梁建設(shè)從施工準(zhǔn)備到工程竣工

12、時(shí)時(shí)刻刻存在著危險(xiǎn).工程建設(shè)中的不安全因素及危險(xiǎn)源眾多,涉及面廣,各因素交叉,層監(jiān)管不力容易導(dǎo)致安全事故的發(fā)生,則帶來(lái)重大的經(jīng)濟(jì)損失和負(fù)面的社會(huì)影響.在橋梁建設(shè)施工過程中,對(duì)不安全因素和危險(xiǎn)源進(jìn)行有效地分析和監(jiān)測(cè),認(rèn)清關(guān)鍵要素,構(gòu)建安全監(jiān)測(cè)指標(biāo)體礎(chǔ)上,開發(fā)出危險(xiǎn)源無(wú)線采集系統(tǒng)和安全監(jiān)測(cè)應(yīng)急救援系統(tǒng),有利于提高對(duì)危險(xiǎn)源的監(jiān)管能力,以達(dá)到減少或降低施的目的. 本文以橋梁重大工程為依托,根據(jù)橋梁施工危險(xiǎn)源清單,通過層次分析法進(jìn)行歸一化處理后確定危險(xiǎn)源的等級(jí),并利用綜合變權(quán)原理實(shí)現(xiàn)橋梁整體的安全性評(píng)價(jià),為后續(xù)安全監(jiān)測(cè)和應(yīng)急救援方案做準(zhǔn)備、GRPS無(wú)線傳輸、GIS數(shù)據(jù)處理的基礎(chǔ)上,編程研發(fā)出無(wú)線采集與智

13、能應(yīng)急救援系統(tǒng),為應(yīng)急決策的制定提供數(shù)據(jù)支持與支持.為了及時(shí)準(zhǔn)確地掌握事故信息以及快速處理和決策,利用通信技術(shù)和計(jì)算機(jī)軟件技術(shù),開發(fā)出針對(duì)施工事故的實(shí)時(shí)GSM短信發(fā)布移動(dòng)告警信息發(fā)布平臺(tái),可以實(shí)現(xiàn)更快、更廣泛以及更有效的應(yīng)對(duì)安全事故所能夠達(dá)到的救援.在對(duì)高速公路進(jìn)行交通組織管理中,由于車道功能的不同,人為強(qiáng)制地使橋梁結(jié)構(gòu)運(yùn)營(yíng)始終處于偏載狀態(tài),使主車道的鋪裝承擔(dān)了比超車道高得多（量值可達(dá)三至四倍）的運(yùn)營(yíng)應(yīng)力水平,因此加快了主車道鋪裝層的疲勞。橋梁施工的安全控制要兼顧人員和物兩個(gè)方面，秉承墩柱的質(zhì)量控制重點(diǎn)要做好以下工作：首先要檢查柱中心位置施工放樣，驗(yàn)收墩柱鋼筋籠，使其符合設(shè)計(jì)標(biāo)準(zhǔn)；然后對(duì)支模前

14、接觸面的松散混凝土進(jìn)行鑿除處理，如果有其他雜物則一并沖洗干凈；接下來(lái)對(duì)立柱模板進(jìn)行質(zhì)量檢查，要求接縫處必須圓滑平整，拼接嚴(yán)密，模板的定位精度、豎直度以及鋼筋保護(hù)層厚度必須符合質(zhì)量要求指標(biāo)。脫模劑的涂刷一定要均勻，并且定位鋼絲繩要求拉緊，以達(dá)到受力一致的要求；對(duì)混凝土施工的基本要求與承臺(tái)或系梁施工要求相同，要求用串筒下料，串筒底部距澆筑的混凝土面不超過2米，澆筑完畢將柱頂混凝土面拉毛。臺(tái)帽的質(zhì)量控制重點(diǎn)有兩個(gè)方面，分別是立模工序質(zhì)量控制和混凝土澆筑工序質(zhì)量控制，在檢驗(yàn)?zāi)０鍟r(shí)，要對(duì)模板的平整性、剛度、尺寸和角度進(jìn)行重點(diǎn)檢測(cè)，同時(shí)要看模板的支撐是否符合要求，另外還要觀察模板接頭處的處理情況。混凝土澆

15、筑要求控制好混凝土的制作質(zhì)量，主要包括原材料質(zhì)量、混凝土配合比等，另外還要控制好振搗施工工藝，如果振搗時(shí)間太長(zhǎng)則有可能出現(xiàn)混凝土分層與走模，而振搗時(shí)間不足則會(huì)出現(xiàn)混凝土的氣泡不能完全排出，從而導(dǎo)致形成蜂窩、麻面等病害。蓋梁要檢查柱頂中心及蓋梁軸線，以及鋼筋骨架放樣，蓋梁鋼筋骨架在成型后要進(jìn)行驗(yàn)收，驗(yàn)收時(shí)要特別注意檢查焊縫質(zhì)量及彎起筋位置，在安裝蓋梁鋼筋后要對(duì)骨架定位進(jìn)行檢查，按設(shè)計(jì)角度調(diào)整柱頂錨固筋，好箍筋。另外還要檢查查鋼筋保護(hù)層厚度，預(yù)埋件、預(yù)埋筋位置是否正確，模板是否采取措施已加固牢靠，箱梁要檢查底板是否清洗干凈，接縫處是否用膩?zhàn)哟蚱剑捎盟芰习鍟r(shí)，要求粘貼緊密、無(wú)破洞、無(wú)鼓包以及無(wú)皺折

16、，伸縮縫梁端要注意設(shè)置楔形塊，預(yù)埋支座鋼板，腹板、底板鋼筋重點(diǎn)檢查正彎矩波紋管定位，確保混凝土澆筑過程中不移位，鋼絞線須事先進(jìn)行編束，整束穿過波紋管，并保證在管內(nèi)不纏繞。不僅要提高安全管理的理論水平，更應(yīng)當(dāng)將理論措施付諸實(shí)踐，結(jié)合法律、經(jīng)濟(jì)、文化和科技手段進(jìn)行安全管理，有利于真正在工程實(shí)踐中取得實(shí)效，為企業(yè)創(chuàng)造出更好的經(jīng)濟(jì)和社會(huì)效益。特別是隨著私營(yíng)運(yùn)輸業(yè)的發(fā)展,貨運(yùn)業(yè)主為追求短期經(jīng)濟(jì)利益,通過改變車廂結(jié)構(gòu)如加長(zhǎng)車廂和加高車軸彈簧等使汽車的載重、軸重及輪載成倍增加。這些車輛對(duì)鋪裝層具有嚴(yán)重的毀壞作用,并使橋梁結(jié)構(gòu)局部超載,加快了主車道鋪裝層的病害發(fā)展。因此,在設(shè)計(jì)中應(yīng)根據(jù)運(yùn)營(yíng)中車輛荷載的實(shí)際分布

17、情況,在明確了橋梁結(jié)構(gòu)受力的基礎(chǔ)上,對(duì)橋面鋪裝層進(jìn)行受力計(jì)算。文獻(xiàn)原文 on bridge Structure theory and design In recent years, our country from the major briering cn to theion of the powerful country move forward. The sustainable development hase international field of structureing, environmental and economic development is the import

18、ant question to promote the bridge engineering construction for sustainable development, meanwhile,depend on the analysis of environmental problems from the bridge engineering construction, the bridge engineering life cycle cost of the .bridge structure holds tier of calculation with in theory to br

19、idge floor shop , gives the recommendation value having fixed thickness ,The project boundary has applied several tens years to every grade highway always middle. Already be out of keeping with the fact that the volume of traffic enhancing, active shop hold increasing with the heavy type, increasing

20、 by and speed of a vehicle surpassing the heavy type automobile with quickly. The bridge floor lays the impingement pretending to bear carriage wheel load tier directly , the bridge floor lays the deformation having loaded the part or all participation betokening girder construction , bridge floor s

21、hop pretends to be a main beam accepting the strenuously complicated driving force system , various form and the distribution laying the structure pretending to be self affect whose strain equally therefore. Bridges currently in effect: The regulation also may consult the T shape beam if there being

22、 no accurate reckoning; the box shape beam handles. Judging from a lot of box beams design, the most designer is to handle to box beam component be in progress according to shape beam. Box beam reality accepts but a force though having one aspect bordering on the T beam, one aspect having being diff

23、erent from the T beam, the with regard to continuous box beam difference are bigger.much influenced by his teacher and the Taoism, saw the political corruption in his country and put forward much useful advice to carry out reform. Unfortunately the emperor of Han would not like to adopt his ideas an

24、d let his country wither away. However the emperor of admired the talent wanted to give him a position in state. Although finally killed owing to listening to the unfaithful advice of , he ruled his country on the principles advocated by . Until that time did the situation come to an end and the uni

25、ted central right come out. Especially box beam bridge floor is in recent years more and more broad, ratio of bay and bridge width is more and more small , does that long thin member still design the box beam according to T beam matching tendon , push down with regard to more and more no proper , le

26、ading to? The box beam framework reinforced bar that the beam designs is difficult to bring the due effect into play like T beam host tendon under actual strenuously circumstances. Therefore, the hypothesis states designing that and box beam reality accept force state disaccords. With material, deve

27、lopment of industry, architectural bearing bridge improvement, make bridge host Liang more and more broad reaching the request accepting a force, big advanced level highway transverse direction across bridge with softer structure. Stiffness attaches importance to bridge transverse direction deficien

28、cy , disadvantageous messenger of transverse direction structure measure bridge floor shop pretends to have shared more than the correct or required number time of internal forces especially in the analysis designing that the middle secretly scheming against puts particular emphasis on the calculati

29、on in main beam direction.When the Medici family regained power in 1512 with the help of Spanish troops, Machiavelli was tortured and removed from public life. For the next 10 years he devoted himself to writing history, political philosophy, and even plays. He ultimately gained favor with the Medic

30、i family and was called back to public duty for the last two years of his life. Machiavelli's greatest work is The Prince, written in 1513 and published after his death in 1532. The work immediately provoked controversy and was soon condemned by Pope Clement VIII. Its main theme is that princes

31、should retain absolute control of their territories, and they should use any means of expediency to accomplish this end, including deceit. Scholars struggle over interpreting Machiavelli's precise point. In several section Machiavelli praises Caesar Borgia, a Spanish aristocrat who became a noto

32、rious and much despised tyrant of the Romagna region of northern Italy. During Machiavelli's early years as a diplomat, he was in contact with Borgia and witnessed rule first hand. Does Machiavelli hold up Borgia as the model prince? Some readers initially saw The Prince as a satire on absolute

33、rulers such as Borgia, which showed the repugnance of arbitrary power (thereby implying the importance of liberty). However, this theory fell apart when, in 1810, a letter by Machiavelli was discovered in which he reveals that he wrote The Prince to endear himself to the ruling Medici family in Flor

34、ence. To liberate Italy from the influence of foreign governments, Machiavelli explains that strong indigenous governments are important, even if they are absolutist.To bridge type structure such as continuous beam bridge , arch bridge and cantilever beam bridge, effect because of load but produce n

35、egative curved regulation or pulling force , make the bridge floor lay the effect pretending to accept pulling force tier but produce the breakdown shouldering the curved regulation area rift , bringing about bridge floor shop dress thereby.experience Machiavelli learned that weak countries had no d

36、iplomatic relationship with other counties. In his work he put forward that the weakest thing in the world was the power that was exaggerated. He tried to persuade the emperor to make a strong army, which would become the solid foundation of any course. While held the same opinion with Machiavelli,

37、he said that the most important task for an emperor was to develop his country in many ways such as increasing the production of agriculture, establish clear encouragement and punishment laws, have a forceful army under his control.Under the influence of his teacher,adhered to the principle that hum

38、an nature was bad. And his developed his ideas to the enumerated kingdom which he thought was the heaven of the earth. He believed that human beings were driven by the greed for profit. We can see some trace in his famous saying: strict mother has kind children, while kind mother has brute children.

39、Both of them believed that the relationship among human beings was a kind of naked interest_oriented relationship. They make use of each other, not believe in others, and would try every means to reach ones aims. Bridge project is a complicated（omitted） its construction has characteristics of long c

40、ycle and huge investmet. Bridge construction process is an open（omitted） working, accompanied by dangers from construction preparing to project completion. The unsafe factors and（omitted）uring project construction involve a wide range of issuses and also w（omitted）ate relationships with each other.

41、Slack regulation（omitted）e hazards can cause accidents, which can bring in major economic loss and negative sociali. manages middle in the organization who carries out traffic on the express highway , different since the lane is functional, person has been to compel a field to make bridge structure be in motion and do business all the time in insisting