r用鋼管樁和貝雷片做現(xiàn)澆箱梁施等工支架施工實(shí)踐

1、management systems and measures established by, and a number of pragmatic, combined part-time workforce education information, the protection of the digital campus construction and sustainable development. six bureau attaches great importance to information technology security, information technolog

2、y security, entrust xx city center for educational information and equipment dedicated to the work. network security leading group was set up, chaired by the education bureau chief, head, for xx education metro-network and information security emergency response leadership. deputy group leader for x

3、x educational metropolitan area network and information security emergency response coordination, command. the team assist leader and deputy leader, responsible for network xx network security and information . team. information security work conference held each semester, and deployment of informat

4、ion security of documents issued on a regular basis. information security assessment is included in the annual index. strictly implement the information security budget to ensure information security of investment. by xx, education information and equipment centre xx network network security and inf

5、ormation security. according to the information technology security requirements, issued a document requires schools (units) implement, defined the information security guidelines, specific work practices, procedures, and requirements. clear industry information security incidents (accidents) to det

6、ect, report and disposal processes. according to self-examination, the school (units) basic established has network security management system; the school (units) according to this units actual, established has units personnel management, information system room management, and equipment management,

7、 and media management, and network security construction management, and shipped dimension management, and service outsourcing, management system; developed has computer and the network of network security responsibility held system, signed has network security responsibility; website of information

8、 management personnel is responsible for confidential management, password management, on computer enjoys independent right, user name and password of the computer for its proprietary, and release of provisions is prohibited, such as leaks, investigated for responsibility. according to who is in cha

9、rge of whos in charge, who is running and who is responsible for, who uses principles of who is in charge of management schools (units) defined the roles and responsibilities of information security, assurance responsibilities to schools. xx city schools (units) total site 20, 19 of which were not c

10、lassified security protection assessment, of which 1 (xx education and resource network) for classified security protection levels, without third-level information systems. total education information systems 1 (xx education cloud platform), contains features with e-government, resource library, tes

11、t database, mail services, such as e-books, all intranet services. no for grade protection grading record and evaluation of school (units), requirements the school (units) according to information security grade protection about policy and standard, organization carried out information security grad

12、e protection security management system construction, and technology measures construction and grade evaluation, implementation grade protection system of the requirements, makes information system security management level obviouslyfacility up to 160 million yuan, according to the standard, high qu

13、ality planning xx educational metropolitan area network realizes wan zhaokuan to schools, hundreds of megabytes of broadband to the table, wire (ie: web, video, audio) to the target, electronic whiteboards, multimedia classrooms, remote interactive video teaching system of modern educational equipme

14、nt in the classroom. . with intel company on xx education city domain network of topic case design, relies on cisco company thought shu aid chuan project staff free provides has three years technology support, from 2009 began, according to high standards, and high of work thought, and manpower plann

15、ing, and points step implementation, using school earthquake hou reconstruction of opportunities, again planning elementary and middle schools campus network and education city domain network, and local broadcasting network company cooperation, using broadcast tv network, will physical fiber laying

16、to each school, to minimum of cost achieved has physical fiber school school pass; each school construction standards of campus network and network access to all rooms; xx education metropolitan area network center machine room equipment in the ministry of education standardization management platfo

17、rm, the central library of audio-visual education resources, set up a chinese teacher education cloud platform, implemented links the two platforms. at present, the citys primary and middle school students to computer 3198, vitality than 10:1; 809 equipment classes through the classroom (primary and

18、 secondary); 36 of the campus network. the establishment of an advanced, practical gigabit educational metropolitan area network, the citys schools have access to educational metropolitan area network, schools have computer networks, closed-circuit television network, broadcast networks into the cla

19、ssrooms, realize the triple play. schools share internet bandwidth, can meet the needs of teaching of the school office and at any time. according to ministry of education on full started implementation teaching points digital education resources full cover project of notification (taught technical

20、letter (2012) 74th,) and xx province department of education on issued xx province teaching points digital education resources full cover project implementation views of notification (chuan taught letter (2013) 18th,) requirements, i city 6 a teaching points implementation teaching points digital ed

21、ucation resources full cover project, combined i city specific situation, developed issued has xx city bureau on teaching points digital resources full cover project of implementation programme, established xx, full coverage of digital resources in modern distance education teaching project leading

22、group, xx, chaired the secretary for education. established, digital resources in modern distance education teaching, xx full coverage project group, xx, director of the center for educational information and equipment chaired zhu guiyan, responsible for distance education digital resources covering

23、 project work. projects in xx city school digital resources in modern distance education teaching full-coverage project leading group, digital resources in modern distance education teaching, and xx full coverage project group leadership and organization, in accordance with the unified arrangement o

24、f the whole province, responsible for university education digital resources covering project management and implementation. according to provinces arrangements, i center has arrangements gong鋼管樁和貝雷片做現(xiàn)澆箱梁支架施工實(shí)踐 鐘本鋒畢業(yè)論文畢 業(yè) 論 文鋼管樁和貝雷片做現(xiàn)澆箱梁支架施工實(shí)踐中鐵二十三局集團(tuán)第一工程有限公司鐘本鋒目 錄1.引言32.現(xiàn)澆支架比較32.1軍用墩與軍用梁組合現(xiàn)澆支架32.2貝

25、雷片和抱箍構(gòu)成移動(dòng)式支架32.3腳手架、萬(wàn)能桿件或軍用墩與型鋼支架42.4鋼管樁、貝雷片和碗扣件支架42.5鋼管樁與貝雷片支架 43.工程實(shí)例43.1工程概況43.2支架的設(shè)計(jì)和施工43.2.1貝雷桁架的設(shè)計(jì)53.2.1.1貝雷片的布置53.2.1.2貝雷桁架的設(shè)計(jì)檢算63.2.2貝雷片的安裝和拆除63.2.2.1鋼管樁支墩的設(shè)計(jì)63.2.2.2鋼管的布置63.2.2.3鋼管排架的設(shè)計(jì)檢算73.2.2.4鋼管排架的拆除83.3支架預(yù)壓83.3.1預(yù)壓施工及成果分析83.3.2對(duì)桁架的改進(jìn)措施83.3.3預(yù)拱度設(shè)置93.4混凝土的澆注103.4.1混凝土的澆注順序103.4.2沉降觀測(cè)結(jié)果分析1

26、04.體會(huì)104.1主要優(yōu)點(diǎn)104.2存在的不足和需進(jìn)一步改進(jìn)的問(wèn)題11鋼管樁和貝雷片做現(xiàn)澆箱梁支架施工實(shí)踐中鐵二十三局集團(tuán)第一工程有限公司 鐘本鋒內(nèi)容提要：在軟弱地基上使用鋼管樁和貝雷片做為現(xiàn)澆支架，避免了處理軟基，克服了地基沉降對(duì)現(xiàn)澆箱梁施工線形的影響；結(jié)合支架施工實(shí)例，著重介紹鋼管排架和貝雷片組成的支架構(gòu)造和施工。關(guān)鍵詞：鋼管樁和貝雷片 支架 實(shí)踐1.引言在軟弱地基上施工橋梁上部現(xiàn)澆梁、板，一般的施工方法是對(duì)軟基進(jìn)行加固處理，然后搭設(shè)滿堂支架施工。由于軟弱地基特殊的地質(zhì)條件，地基處理難度較大；同時(shí)由于處理厚度的不均勻性，當(dāng)填加施工荷載時(shí)，地基將可能出現(xiàn)不均勻的沉降，從而可能對(duì)混凝土的質(zhì)量

27、造成不同程度的損傷，對(duì)工程質(zhì)量留下隱患。且地基處理為一次性投入，處理費(fèi)用高，周轉(zhuǎn)利用率低。隨著工程技術(shù)的發(fā)展，人們?cè)诠こ虒?shí)踐中摸索出減少或避免處理地基的施工方法，使支架越發(fā)安全可靠。2.現(xiàn)澆支架比較盡可能地利用既有墩臺(tái)基礎(chǔ)，以避免或減少處理地基，根據(jù)使用器材的不同，在實(shí)踐中逐步摸索出幾種現(xiàn)澆支架模式，可用在軟地基基礎(chǔ)上。列舉其中的部分結(jié)構(gòu)形式如下。2.1軍用墩與軍用梁組合現(xiàn)澆支架支架基本形式見(jiàn)圖1。軍用梁承載力強(qiáng)，根據(jù)不同跨度在孔間設(shè)置支墩，可拼裝出不同跨度的支架，但由于為制式器材，在器材型號(hào)不全時(shí)，跨度拼裝將受到很大限制；軍用梁自重大、對(duì)支撐墩和基礎(chǔ)要求較高。該支架在青島流亭立交橋、濟(jì)青高速

28、公路后劉立交橋等橋梁現(xiàn)澆梁施工中先后得到應(yīng)用。2.2貝雷片和抱箍構(gòu)成移動(dòng)式支架利用貝雷片拼裝成支撐橫梁和縱梁，抱箍固定在橋梁墩身上，作為體系的承重構(gòu)件，利用卷?yè)P(yáng)機(jī)拖動(dòng)縱梁前移，實(shí)現(xiàn)可移動(dòng)式現(xiàn)澆支架。見(jiàn)圖2。該支架形式在廣東肇慶大橋北岸連續(xù)箱梁施工中得到應(yīng)用。支架結(jié)構(gòu)簡(jiǎn)單，受力明確，操作簡(jiǎn)便；缺點(diǎn)是適用跨度較小，適用于圓柱形墩，混凝土施工過(guò)程較復(fù)雜。2.3腳手架、萬(wàn)能桿件或軍用墩與型鋼支架用腳手架或萬(wàn)能桿件搭設(shè)支墩，采用型鋼組成作為現(xiàn)澆支架，根據(jù)型鋼的不同型號(hào)可根據(jù)要求做成不同跨度的支架。較常用的支架跨度一般在6m左右，跨度較大的可用至9m。結(jié)構(gòu)形式見(jiàn)圖3。使用較靈活，但支墩基礎(chǔ)較密，處理費(fèi)用相

29、對(duì)較高。2.4鋼管樁、貝雷片和碗扣件支架利用鋼管將貝雷片架立地面，然后在貝雷架上支立碗扣件，構(gòu)成支架。該種支架利用貝雷片代替地基處理，材料周轉(zhuǎn)利用率高，適用性強(qiáng)，安全可靠，但材料投入較大。結(jié)構(gòu)形式見(jiàn)圖4。2.5鋼管樁與貝雷片支架 圖 4根據(jù)現(xiàn)澆構(gòu)造物的高度，將鋼管樁制作成排架形式，做為支架的支撐墩，上部用貝雷片拼裝成連續(xù)梁式桁架。用固定在貝雷片主弦桿上的方木做標(biāo)高調(diào)整構(gòu)件。該支架的特點(diǎn)是：支架材料投入少，重量輕，施工機(jī)械化程度高，適用的跨度相對(duì)較大。結(jié)合工程實(shí)例對(duì)該種支架重點(diǎn)介紹。3.工程實(shí)例3.1工程概況通啟高速公路陳橋互通立交主線橋，位于江蘇省南通市，地處長(zhǎng)江三角洲沖積平原，地層為第四系全

30、新系統(tǒng)及上更新系統(tǒng)，表層分布1.56.5m厚的軟塑狀亞粘土，下臥軟塑狀亞砂土，軟土地基多埋藏在地表下10m以?xún)?nèi)，地基承載力較差。大橋上部結(jié)構(gòu)為現(xiàn)澆連續(xù)箱梁，分左右兩個(gè)半幅。箱梁為單箱雙室斷面，標(biāo)準(zhǔn)斷面尺寸見(jiàn)圖5。橋墩高度為611m?？鐝?0m， 基礎(chǔ)為樁柱式柔性墩。 3.2支架的設(shè)計(jì)和施工 鋼管支架設(shè)計(jì)主要要解決兩方面的問(wèn)題：一是臨時(shí)支墩的結(jié)構(gòu)形式，二是由貝雷片組成的桁架整體強(qiáng)度、剛度和穩(wěn)定性。下面著重就這兩方面的問(wèn)題進(jìn)行分析探討。使用的主要材料為：直徑273 mm，壁厚6mm的鋼管；321型的貝雷片（高1.5m，每節(jié)長(zhǎng)3.0m）。3.2.1貝雷桁架的設(shè)計(jì)現(xiàn)澆支架的整體布置形式見(jiàn)圖6。圖63.

31、2.1.1貝雷片的布置貝雷片的結(jié)構(gòu)布置形式見(jiàn)圖7。沿箱梁橫斷面方向設(shè)置9道貝雷片，均勻布置。桁架頂部橫向布設(shè)1012cm的方木，間距30cm，用鐵絲或鐵釘與貝雷片主弦桿綁扎牢靠（預(yù)先在貝雷片主弦桿上綁扎調(diào)整方木）；方木在箱室肋部加密一半，間距為15cm；方木長(zhǎng)度為3m交錯(cuò)布置，并使位于同一貝雷片上的方木接頭不超過(guò)通過(guò)該貝雷片方木總面積的50%，做為底模板橫肋，兼做貝雷片的上水平聯(lián)；沿支架縱向每2.8m設(shè)置橫向鋼結(jié)構(gòu)連接系一道，以保證9道貝雷片整體受力。為保證貝雷片的整體穩(wěn)定，在位于箱梁兩外側(cè)豎肋的三片桁架底部用758角鋼與橫向連接系焊接，組成下水平聯(lián)。見(jiàn)圖8。3.2.1.2貝雷桁架的設(shè)計(jì)檢算施

32、工荷載主要由鋼筋砼自重q1、模板自重q2、貝雷桁架自重q3、施工荷載q4構(gòu)成。支架承受的總荷載為：q=q1+q2+q3+q4 =229.5kn/m。強(qiáng)度檢算 貝雷架縱向布置形式為間距6米和14米間隔布置的連續(xù)梁，最不利情況發(fā)生在14米跨度內(nèi)混凝土全部澆注完成，其它跨徑內(nèi)沒(méi)有荷載時(shí)。按簡(jiǎn)支梁計(jì)算。則最大彎距：mmax=ql2/8=229.5142/8=5621.5knm，單片貝雷架承受最大彎距（按荷載橫向均勻分布計(jì)算，不考慮不均勻分布系數(shù)）：m=mmax/9 =5621.5/9=624.6 m=975 knm,滿足要。撓度檢算因貝雷片每節(jié)結(jié)構(gòu)形式相同，可看作勻質(zhì)梁，并以簡(jiǎn)支梁模型檢算，最大撓度為

33、：f=（5/384）ql4/（eiix）=(5/384)229.514004/（2.11062505009）=2.4cml/400=1400/400=3.5cm滿足施工要求（其中貝雷架的慣性矩ix=250500cm4）。3.2.2貝雷片的安裝和拆除將每5片貝雷片拼裝成整體桁架，用16t吊車(chē)起吊就位；一聯(lián)全部貝雷片安裝完畢，加設(shè)橫向支撐、上平聯(lián)和下平聯(lián)。貝雷桁架采用整體落架法拆除。在貝雷桁架的底部（近支墩處）各設(shè)一根橫梁，橫梁用20t手拉葫蘆懸吊在箱梁翼緣板承托上（在承托上預(yù)留懸吊孔），落架時(shí)先拆除支墩，再拆除桁架的平聯(lián)，拔掉貝雷片間的連接銷(xiāo)子，松動(dòng)手動(dòng)葫蘆貝雷桁架脫模下落。3.2.2.1鋼管樁

34、支墩的設(shè)計(jì)支墩排架的基本結(jié)構(gòu)形式見(jiàn)圖9。3.2.2.2鋼管的布置主要解決的問(wèn)題是：在保證每排排架承載能力的前提下，保證鋼管樁的整體穩(wěn)定性和抗傾覆能力。具體措施：鋼管樁頂部與工字鋼焊接牢靠，底部與預(yù)埋鋼板焊接，沿鋼管高度方向每4m用14焊接一道橫向連接撐，構(gòu)成一個(gè)排架；將同一個(gè)承臺(tái)上的兩個(gè)排架頂部用14連接，形成上平聯(lián)，兩排間用3道14連接成人字撐。使兩個(gè)排架形成一個(gè)受力整體，增強(qiáng)抗傾覆能力。3.2.2.3鋼管排架的設(shè)計(jì)檢算9.003.381.6943.381.11.1按如下不利條件假定荷載:每?jī)蓚€(gè)排架承受跨度為23m的箱梁鋼筋砼重量,并按簡(jiǎn)支梁模型計(jì)算支反力。作用在排架上的荷載構(gòu)成如下：鋼筋砼

35、重力q1、工字鋼自重q2、其他荷載q3，則每個(gè)排架承受的總荷載為：p= q1q2q3=2645.5kn由于每個(gè)排架承受的總荷載由9道貝雷片均勻分部在工字鋼上，每處荷載為：q=p/9=294kn。荷載布置如圖10。將每個(gè)排架看作剛架計(jì)算,并按鋼管最大高度9.0m計(jì)算。上述剛架為對(duì)稱(chēng)剛架,取一半研究，采用力矩分配法計(jì)算。 圖10。cdcgcbbcbfba14.9 -33.3 0.7 32.5 129.2 -3.3 -125.97.3 -7.3-0.5-0.5 0 -0.90.1 2.7.-2.8-0.4 0 -0.91561.5 31.1-2.5-4.9 0.2 9.8-30.129.7 0.7

36、29.7-60.1-60.1 -2.9 -120.259.25.7 118.3124-124gfedcbaaeab0.0460.9540.3280.0160.6560.4940.0120.494-5.1 -0.2 -10.3-5.21.32.6 0 2.61.31.414.916.2i45b工字鋼轉(zhuǎn)動(dòng)慣量為:i1=33.7591074; 273,壁厚6鋼管轉(zhuǎn)動(dòng)慣量為:i2=44.848106,材料相同為a3鋼,彈性模量相同。計(jì)算各節(jié)點(diǎn)的分配系數(shù)、計(jì)算過(guò)程見(jiàn)圖11。圖11固端彎矩mab=-ql/8=2943.375/8=-124knm,mba=-mab=124knm由各節(jié)點(diǎn)的彎矩和外力,根據(jù)力矩

37、平衡可得節(jié)點(diǎn)剪力;由計(jì)算出的剪力,根據(jù)節(jié)點(diǎn)力的平衡原理可得各桿的軸力（壓力）如下:nae=405.6kn, nbf=571.4kn,ncg=170.8kn, n中=351.8kn鋼管強(qiáng)度檢算：取壓力最大桿件bf,桿件自由長(zhǎng)度為4m，視為兩端鉸接桿，其柔度=l/r=14000/94.4=42.4 查表可得=0.89，則鋼管樁的穩(wěn)定強(qiáng)度為：= n/(a)=571.4103（5030 0.89）=127.6mpa=170 mpa滿足要求。鋼橫梁檢算：鋼橫梁實(shí)際有7個(gè)支點(diǎn)，按5個(gè)支點(diǎn)計(jì)算。其中5道貝雷架架設(shè)在鋼管樁樁頂，其余4道架設(shè)在跨中，鋼橫梁為4跨連續(xù)梁,查表得:mmax=(0.1998-0.03

38、68+0.0101-0.003)pl=168.8knmw=m/w=1206cm3 w i45b= 1500.4cm,故選用45b工字鋼滿足施工要求。3.2.2.4鋼管排架的拆除為保證排架受力的整體性，不使用砂箱等落架構(gòu)件，采用直接割除鋼管落架。具體做法是：將排架頂部的工字鋼用鋼絲繩和手拉葫蘆吊在桁架上，用氣割將鋼管根部與預(yù)埋件割開(kāi)，慢慢放松手拉葫蘆將排架拆除，整體移至另半幅。3.3支架預(yù)壓3.3.1預(yù)壓施工及成果分析加載采用周?chē)鷩按虚g裝散砂的方法，模擬施工荷載。因砼分兩次施工，預(yù)拱度參照支架在箱梁80%自重時(shí)產(chǎn)生的變形設(shè)置。加載前，沿模板縱橫向每5m開(kāi)設(shè)4040cm活動(dòng)孔一個(gè)，預(yù)壓結(jié)束時(shí)將

39、運(yùn)輸車(chē)開(kāi)到活動(dòng)孔處，將砂子直接泄至車(chē)內(nèi)。加載總重量為23m跨度箱梁自重。沉降觀測(cè)結(jié)果見(jiàn)表1。可以看出實(shí)測(cè)彈性變形與計(jì)算值基本相符，但在支架跨中出現(xiàn)了不均勻沉降，需進(jìn)一步采取加固措施。3.3.2對(duì)桁架的改進(jìn)措施通過(guò)預(yù)壓觀測(cè)成果分析，跨中出現(xiàn)了橫向不均勻沉降。由于貝雷片跨中所受的彎矩較大，荷載出現(xiàn)了橫向不均勻分布，原設(shè)計(jì)的橫向加固結(jié)構(gòu)未達(dá)到預(yù)想效果。為保證箱梁的線形，防止混凝土開(kāi)裂，在桁架的中部增設(shè)4根16的型鋼，間距1.0m，以加強(qiáng)跨中的橫向分布剛度。見(jiàn)圖七。3.3.3預(yù)拱度設(shè)置根據(jù)支架實(shí)際情況和預(yù)壓成果，預(yù)拱度設(shè)置分為6m和14m跨兩部分，考慮不可預(yù)料的因素及箱梁的外形美觀，將預(yù)拱值提高35m

40、m，跨中最大值設(shè)置為25mm。并按拋物線分配，見(jiàn)圖12： 沉降觀測(cè)結(jié)果 表1觀測(cè)點(diǎn)編號(hào)荷重0荷重80%沉降量卸載后非彈性變形彈性變形觀測(cè)值觀測(cè)值觀測(cè)值0左12.78212.778412.78022中12.87212.868412.87113右12.97112.967412.967400.25l左12.70512.6852012.701416中12.78612.7662012.781515右12.89912.8801912.8936130.5l左12.63312.6102312.628518中12.73912.7083112.731823右12.83712.8162112.8325160.75l

41、左12.53312.5181512.530312中12.62312.6081512.624015右12.73512.7201512.730510l左12.44712.442511.44705中12.53712.530712.53434右12.64012.635512.63732l+3米左12.40112.399212.40011中12.49612.492412.49422右12.59312.587612.591243.4混凝土的澆注3.4.1混凝土的澆注順序現(xiàn)澆箱梁分段施工，每段分兩次澆注。為有利于支架的受力、減小支架變形，每段混凝土澆注順序?yàn)椋嚎v向從每段的起點(diǎn)向終點(diǎn)澆注；橫向從起始跨的中間腹

42、板和底板向兩側(cè)對(duì)稱(chēng)澆注。3.4.2沉降觀測(cè)結(jié)果分析 在混凝土澆注過(guò)程中，觀測(cè)支架變形，測(cè)量成果見(jiàn)表2?？梢钥闯隹缰凶畲蟪两盗繛?2mm，小于預(yù)拱值3mm，橫向不均勻沉降最大為3mm。從拆模后的箱梁底板外觀看，線形順暢、美觀，達(dá)到預(yù)期要求。按預(yù)拱值25mm設(shè)置正確、可靠。 支架變形觀測(cè)成果 表2觀測(cè)點(diǎn)編號(hào)澆筑一次砼前第一次砼澆筑后沉降量（）第二次砼澆筑前第二次砼澆筑后沉降量（）最終沉降量（）觀測(cè)值觀測(cè)值觀測(cè)值觀測(cè)值0.25l左136921368661368613678814中135941358771358013571916右1350713501613498134908140.5l左1378213

43、774813774137631119中13694136841013682136711121右135961358610135841357212220.75l左1386013855513854138441015中134411343561343513427814右1365913655413656136451115l左13726137233137231372036中13689136872136881368446右137111370921371013707354.體會(huì)4.1主要優(yōu)點(diǎn)利用鋼管樁和貝雷片做現(xiàn)澆支架，直接利用既有承臺(tái)作為支架的支撐基礎(chǔ)，不需處理地基，避免地基沉降帶來(lái)的影響，節(jié)約了投資，提高了材

44、料的回收利用率。將主要受力構(gòu)件加工成大塊，用機(jī)械吊裝，提高了機(jī)械化作業(yè)程度和工效，節(jié)省了時(shí)間。整體落架法拆除桁架，不僅減少了高空作業(yè)量，保障了施工安全，而且提高了工效。直接利用固定在貝雷片主弦桿上的方木代替鋼管調(diào)整高程，節(jié)約了投入。4.2存在的不足和需進(jìn)一步改進(jìn)的問(wèn)題鋼管的接長(zhǎng)和拆除，全部采用電焊、氣割，現(xiàn)場(chǎng)焊接工作量大，對(duì)操作工人的要求高，且對(duì)鋼管質(zhì)量有損傷。改進(jìn)措施：將鋼管分段加工成型，根據(jù)需要組拼。由于貝雷片采用非標(biāo)準(zhǔn)間距布設(shè)，橫向及底水平連接主要采用了焊接方式，現(xiàn)場(chǎng)焊接量大，工效低。改進(jìn)措施：改焊接為栓接。參考文獻(xiàn)：劉宗祿.流亭立交橋連續(xù)箱梁施工技術(shù)總結(jié).鐵道建設(shè)優(yōu)秀論文選編.中國(guó)鐵道

45、建筑總公司1991-1993.黃紹金.劉陌生.裝配式公路鋼橋多用途使用手冊(cè).張克治.后張預(yù)應(yīng)力連續(xù)箱梁施工.京福高速公路論文集.improve, security prevention capacity obviously enhanced, security hidden and security accident obviously reduced, effective guarantees information health development. xx education centre regularly carry out day-to-day network security

46、monitoring information and equipment. by the appropriate technical staff, xx network engine room maintenance staff on site management and maintenance on a regular basis, scheduled viewing of networks, systems, databases and associated equipment operating conditions, and make a record. computer lab m

47、aintenance managers regularly run a variety of devices in the school information system parameters, server systems and various data backup, so that there was a hardware failure in a system crash can resume quickly and efficiently. computer lab maintenance managers establish a network antivirus syste

48、m, avira virus system on a regular basis, and anti-virus software security assessment, time to upgrade. computer lab maintenance management for all equipment in the room a regular dust, replace the old label. regularly host servers, network switches, core routing, firewalls, hardware maintenance, su

49、ch as equipment failure, should be processed in a timely manner in order to ensure safe and reliable operation of the system. in xx city information and equipment was established within the centre, educational metropolitan area network center machine room xx. servers and data stores and applications

50、 to set up in xx city metropolitan area network center machine room. windowsserver2003, windowsserver2008, windowsserver2012, linux, the operating system, the database for sql server2008, office software, such as microsoft office software. schools (units) of computer, information system security pro

51、ducts for domestic products, including the use of 360 and kingsoft internet security software. xx education metropolitan area network used by the server for hp, firewall and information security product for huawei and cisco products. in their daily work, to publicize related knowledge and informatio

52、n security considerations. enhanced global awareness of network and information security, and strive to achieve network everyone knows security and virus before the guard, to improve network and information security, ensure that the xx education system network and information system security. tracki

53、ng reporting system requires all parties to strengthen collaboration, work closely with emergency safety plan developed xx education metropolitan area network, regularly carry out emergency drills, and carried out special funds every year to protect the security of information. annual 2-3 profession

54、al training for network managers in the city, forming technology with a strong professional and technical team, school network managers on common network failures and be capable of solving security issues. issues that cannot be resolved, timely forms of meetings, such as meetings, analysis, and solu

55、tions through a meeting, without rolling up the ability to solve problems, and feedback to superiors in writing departments to resolve. through self-examination, we are well aware, relative lack of investment in education, facilities and equipment for further updates, education development is still uneven, new education concepts need to be further enhanced to some extent and restricting the development of city education