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1、 底拱翻模施工技术摘要：三峡永久船闸地下输水系统隧洞体形结构复杂，表面质量要求高，平洞底拱按常规方法施工，混凝土表面缺陷无法消除。底拱翻模抹面技术成功地解决了这一难题，施工后混凝土表面光滑平整，消除了水汽泡、麻面等混凝土施工中的“顽症”，满足了设计需要。 关键词：地下隧洞 混凝土施工 底拱翻模 三峡工程 1 概况 三峡永久船闸地下输水系统由3条（衬后为4条）输水隧洞和36口竖井组成，其中包括16口斜井及72个渐变段，隧洞总长约5 500m。隧洞结构设计复杂，洞洞交叉，洞井相贯，断面多变，其中平洞标准段衬砌断面为11种之多
2、，最长一段直洞长度仅约为128 m。标准段除有少部平洞外，其余均为坡比17或18的斜坡段，斜坡升降处均为圆弧过渡，进出口处还设有平弯，72个渐变段共有19种不同的尺寸。 1.1 结构特点 平洞底拱除闸室段为方形、渐变段为两条小圆变方或方变小圆、T型管及十字管为两条45倒角外，其余标准段底拱均为宽5 m，两侧为R50 cm的反圆弧，南北坡衬砌厚60 cm，中隔墩衬砌厚100 cm。标准段底拱断面结构见图1。 1.2 施工步骤 平洞混凝土施工程序分为两步：先浇底拱，后浇边顶拱。底拱浇高7090 cm，圆弧上去2040&
3、nbsp;cm，以便边顶模板搭接。浇筑长度南北坡为8 m，中隔墩为12 m。 1.3 表面平整度要求 由于通航后隧洞表面要承受高达30 m/s水流的冲刷，为提高混凝土表面的耐久性，浇筑后混凝土表面平整度质量要求高。表面平整度用3 m直尺检查，类区垂直水流方向的起伏差小于3 mm，平行水流方向的起伏差小于5 mm，纵坡1/50，不允许在混凝土表面出现蜂窝、麻面、水汽泡及直径或深度大于5 mm的气孔洞。 2 初期施工及试验情况 永久船闸地下输水隧洞从1999年9月29日第1块底拱结构混凝土开始浇筑。底拱模板结
4、构反弧部分R50 cm及边墙采用定型钢模板，两边用桁架相连，底板3 m段采用人工刮平抹面。底拱定型模板结构见图2。 由于混凝土浇筑时，反弧部分汽泡难以排出，聚积吸附在模板表面，脱模后在混凝土表面出现大量的水汽泡、麻面；同时中部桁架密集，人工刮平抹面困难，致使底板平整度较差，极大地影响了混凝土表面质量。 针对初期底拱浇筑中出现的表面质量问题，进行了各种相关试验，包括不同的振捣时间，模板开孔，木模板和在钢模板加内衬等几种条件的试验。 为了保证试验效果，还在钢模板及木模表面铺定吸湿性好的土工织物和生白布，但土工织物和生白布只能周转23次，成本高，且无法彻底解决表面平整度及水汽泡。
5、经多次试验，我们认为，只有改变常规的施工方案改善工艺措施才能消除底拱混凝土表面水汽泡，因此，我们采用新的施工方法底拱翻模抹面技术。 3 底拱翻模 底拱翻模抹面技术投入使用后，在施工中得到了不断完善和发展。目前，底拱翻模主要分为底拱翻模台车和底拱小翻模两种结构形式。 3.1 底拱翻模台车结构 底拱翻模台车为整体结构，主要由模板、台车架、拖板、撑杆、行走轮、支架及轨道等组成，见图3。 模板包括R50 cm反弧段、高40 cm边墙及50 cm底板直段，面板厚6 mm。模板每块长2 m，模板间用螺栓连接。 台车架主要由型钢组成，分为
6、4 m一段，底部拖板导轨固定于台车架上。行走轮移动时固定于台车架上；浇筑时在台车架两端用钢凳支撑住。 手动撑杆用于模板支撑及脱立模，当用手动撑杆把模板脱空后，换用12 t手拉葫芦把模板拉拢台车架，并用挂钩把模板固定于台车架上。 拖板长约2.7 m，宽50 cm，上置2只1.1 kW平板振捣器。刮板前后往返运行时用1 t手拉葫芦进行牵引。 轨道采用12槽钢。后部轨道置于底板混凝土上，前部轨道置于已绑扎的底板钢筋上。轨道前后循环，重复使用。 3.2 底拱小翻模结构 底拱小翻模主要由模板、背肋、拉筋、样架、刮轨及支架等组成，见图4
7、。 模板同样包括R50 cm反弧段、高10 cm边墙及底板。模板面板厚3 mm，高55 mm，每块模板长1.2 m，模板相互间用形卡相连。 背肋紧贴模板内肋，以便通过拉筋把模板拉紧固定。背肋分为横、纵向，均用1.5钢管，纵肋弯制而成，间距60 cm。 刮板用方钢或槽钢制成。刮板导轨用25圆钢通过尼龙锥套与底板钢筋固定，混凝土平整后把导轨及锥套取出，人工抹平。 支架由1.5钢管通过用碗扣连接而成。支架主要用于模板拆翻、振捣、抹面及混凝土输送泵管架设。 3.3 底拱翻模技术参数及施工程序 底拱翻模主要技术参数如下。 序相同：扎筋
8、立模校正浇筑平仓振捣翻模抹面模板移装。不同之处主要为：一是底拱台车整体移装，拖板导轨固定于台车架上；而底拱小翻模分块移装，刮板导轨固定于底板钢筋上；二是底拱台车车架可作施工平台及混凝土输送导管架，而底拱小翻模需另搭设施工平台。 平洞底拱用翻模施工，只要根据混凝土初凝强度，掌握好翻模时间，把混凝土表面抹平、压光，便可彻底消除混凝土表面水汽泡、麻面及错台。 3.4 底拱翻模工艺措施 （1）塌落度控，制混凝土浇筑采用泵送分层平铺入仓，浇筑层厚50 cm，塌落度严格控制在1216 cm之间。 （2）浇筑顺序，先将混凝土浇筑至底板内层钢筋以下，然后改由边墙下料，当混凝土由边
9、墙圆弧模板底部溢出后，再从中间底板下料至底板高程，最后再把边墙浇满。 （3）平仓振捣，混凝土入仓后，骨料有堆积的地方采用人工及时平仓分料及振捣；振捣棒作业时要求“快插慢退”，振捣时间控制在4050 s，以混凝土不再冒气泡且表面泛浆为止。 （4）底板平整，收仓后，底板混凝土略高于设计高程，初步用拖板或刮板进行平整处理，最后用抹铲人工找平、压光。 （5）翻模、抹面，混凝土初凝强度达到0.10.3 MPa时，按浇筑顺序逐块翻起模板，用泥铲抹平、压光残留于反弧段混凝土表面的水汽泡、麻面及错台等，消除表面缺陷。 4 施工应用与拓展4.1 底拱翻模台车施工底拱翻
10、模台车于1999年5月18日首次用于南-平洞S4块底拱浇筑1。底拱翻模台车整体进行脱立模、移位；混凝土浇筑后，按混凝土浇筑顺序逐块翻转模板，对反圆弧面等存在水汽泡、麻面的部位进行人工抹面、压光，较好地解决了混凝土表面缺陷。但由于台车重量大，移位、翻转较困难，翻模时间较长，易错失最佳抹面时机；模板翻转时易对相邻块产生扰动，在混凝土表面产生裂纹；同时，由于台车架空间较小，不利于进行拖板、抹面作业。4.2 底拱小翻模施工底拱小翻模于2001年7月20日首次投入北-N16平洞底拱施工。虽然模板小块拼装，需设置较多拉筋、搭架等，工序较繁杂，但模板重量轻，装拆、转移方便，时间短，易于把握住最佳抹面时机；底
11、拱刮平、抹面施工空间大，模板翻拆时不易扰动相邻块，混凝土表面无裂纹；在与边顶拱同步施工中，利于边顶台车的安装、材料运输及混凝土输送，而且适用于弯道施工，所以底拱小翻模在平洞施工中显示出较强的适用性。4.3 底拱翻模的拓展底拱小翻模结构简单，适合于地下洞室施工，所以在后来的施工中，底拱小翻模又发展应用到平洞旁弯、升坎溢流面、渐变段、闸室段、T型管、十字管、56.9的斜井上、下弯段及直段部分底板等。断面形式多样，有圆弧形、45倒角及圆变方或方变圆等；模板既有钢模，亦有木模。为底拱混凝土的优质施工奠定了坚实的基础。另外，底拱小翻模除在三峡永久船闸地下输水隧洞中广泛使用外，还在三峡右岸地下电站厂房引水
12、隧洞中得到了成功应用。引水隧洞直径为13.5 m，底拱翻模结构见图5。用底拱翻模抹面技术施工，混凝土表面光滑平整，彻底消除了表面水汽泡、麻面等，满足了设计质量要求，还可节省大量的缺陷处理费用和时间，减少了三峡电站通航发电后，隧洞混凝土表面在高速水流冲刷下发生气蚀的可能性及维修的机率，具有较大的经济效益和社会效益。/Porganization system and working mode, the selection of a number of municipal strengthening group to build innovation and strengthen the organ
13、ization of the basic level organizations advanced model.(seven) the manual work of the Communist Youth League Organization published and League branch of manual work, to promote the use of two manuals in the citys organizations at various levels. The county committee, directly under the group (work)
14、 is under the jurisdiction of grassroots League and group (total) using branch ratio shall not be less than 70%.Three, to further strengthen the groups leadership and team building(a) to strengthen the leagues leadership at all levels of construction. Continue to do a good job of municipal Party Com
15、mittee Organization Department on the strengthening of the Communist Youth League cadres management opinions implementation. To promote the group counties (autonomous counties, cities) Commission and city directly under the group (workers) appointed to carry out the Five team building activities. Im
16、prove the League Association Department working mechanism. Conscientiously fulfill the duties of CO, combined with the city group directly under (the) Committee of the general election and the adjustment, actively jointly with the unit where the party organization department good group leadership se
17、lection with the work. Do a good job in municipal Party committee assistant committee leadership and leading cadres of the annual assessment work, adhere to and improve the assistant secretary of the Communist Youth League talk system group To weave individual conversation and collective conversatio
18、n, to strengthen the committees of all levels, the Standing Committee of the Standing Committee, the establishment of a sound system of central group learning, the system of investigation and study, the system of important issues and the reporting system.(two) to strengthen the work of education and
19、 training of cadres to conscientiously implement the Central Committee. On the implementation of grassroots cadres training project and opinions on carrying out the mission municipal CYL Cadres training project implementation opinions, full implementation of the project of the City Youth League cadr
20、es training education. Focus on the county grassroots cadres and workers focused on training, the new school system vocational training League cadres, for the Municipal Organization Department jointly held the third session of the Communist Youth League system training cadres in party. Focusing on t
21、he construction of new socialist countryside, strengthening village cadres and rural construction team group member of the young team, the county organizations at various levels throughout the year is expected to train 100 00 rural grassroots cadres, plans to train 1000 village secretary of the vill
22、age Party branch.(three) actively promote grassroots cadres election work. Under the unified leadership of the party organization, to strengthen grassroots organizations direct work, standardize the election work rules and procedures, in the designated candidate, open competition to democratically e
23、lected branch secretary at the same time, actively and steadily the development of Township, streets and other grassroots organizations in the direct election of the pilot work, on the basis of summarizing the experience and gradually expand the scope of the pilot, and gradually formed a set of meas
24、ures and cadres election system.(four) to strengthen the cadres testing exercise. To study the development of XX city from 2006 to 2008 cadres testing exercise planning. To select outstanding cadres to the central mission in Beijing, Shanghai, Guangzhou and other central organs and sending work in d
25、eveloped areas. With the Central Committee the implementation of the western region and ethnic minorities cadres training plan . To carry out the eighth batch of municipal organs attachment cadre management, selection, training work. The outstanding cadres to start the National Development Bank XX b
26、ranch testing exercise.(five) to strengthen the group construction. The main position to play the role of Youth League cadre education and training as the city, in accordance with the requirements of post training, further curriculum scientifically and rationally, adopt arrangement menu course, basi
27、c theory includes group work, focus, hot and difficult issues, to enhance the content and practice; to strengthen the construction of teaching staff, the integration of teachers, establish a quality teacher training team, establish and implement course evaluation system; take delivery of training to
28、 the countryside, on-site training, and increase the rural grassroots cadres training efforts.Four, efforts to strengthen the work of young talent(a) to tenth XX young 54 medal in recognition of the publicity, and actively explore the XX youth service. 54 Medal of institutionalization, standardizati
29、on and socialization mechanism. Give full play to the XX award in recognition of 54 youth medal Association, Youth Award winner in the 54 chapter, investigation activities. Who won the Youth Service medal, dedication to the society to create conditions, build the stage. During the 54, named in recog
30、nition of the tenth XX young 54 medal. The association of XX editing of young talent , the exchange of information and communication platform for the XX of outstanding young talents.(two) the establishment of municipal Party committee of young talent information database. In accordance with the feas
31、ible, effective, classification management, implement step by step principle, the establishment of municipal Party committee of youth talent database; guiding organizations at various levels generally established the young talent database, construction of city, county (directly under the Communist Y
32、outh League), grassroots organizations three young talent information database the relevant information collection system, and gradually establish the citys young people, the Communist Youth League youth talent information network, provide information platform for young talent resource development.F
33、ive, take effective measures to strengthen the mission management(a) to strengthen the mission management work. Strengthen the dues collection and management, continue to adhere to the dues collection regularly reporting system, the annual comprehensive award in recognition of the tour and the tour
34、one vote veto system audit system. Do statistical work in the group. The group service award in recognition of the advanced units, standardization, promoting group management work institutionalized.(two) to strengthen the organization of research and information exchange efforts. Grassroots carry ou
35、t research, efforts to form a number of theoretical results. Make full use of the network carrier, to explore the establishment of electronic group service system, promote the work of Communist Youth League information.Attachment 4:XX municipal Party Committee Propaganda Department of the Communist
36、Youth League work pointsIn 2006, the Communist Youth League propaganda ideological work XX to Deng Xiaoping theory and the important thought of Three Represents as guidance, study and implement the partys sixteen and the spirit of the the fifth Plenary Session of the 16th CPC Central Committee imple
37、mentation of the eight plenary session of the two committee, the citys cultural work conference, the Propaganda Department of the meeting and the the fourth Plenary Session of the 15th CPC Central Committee permanent mission spirit, closely around 11th Five-Year XX the goal of full implementation of
38、 Scientific Outlook on Development, emancipating the mind, seeking truth from facts, keep pace with the times, close to reality, close to life, close to the young, persevere grasp orientation, grasping deepening, grasping construction innovation, further improve the groups propaganda and ideological
39、 work ability, unity To guide the majority of members of the youth to achieve the 11th Five-Year planning tasks, the overall construction of a well-off society, building a socialist harmonious society to make new contributions.One, adhere to the Three Represents important thought and Scientific Outl
40、ook on Development education to guide the youth, to further strengthen the ideological and political education of youth(a) armed with youth science theory. Unremittingly with Deng Xiaoping theory and the important thought of Three Represents armed members of youth education, to promote the study and
41、 implement to expand the depth and breadth. To study and implement the important thought of Three Represents with the establishment and implementation of Scientific Outlook on Development combine with the implementation of the requirements of constructing socialist harmonious society with Scientific
42、 Outlook on Development, carry out education as an important part of the theory of armed youth in the new period, strengthen the establishment and implementation of Scientific Outlook on Development education, educate and guide the youth to fully understand the great significance of establishment an
43、d implementation of Scientific Outlook on Development, in-depth understanding of the Scientific Outlook on Development era back The king, the practice foundation, basic connotation, historical status, spirit and practice requirements, a profound understanding of Scientific Outlook on Development wit
44、h Marxism Leninism, Mao Zedong thought, inheriting and developing relationship between Deng Xiaoping theory and the important thought of Three Represents, to help young people establish and consciously practice Scientific Outlook on Development. Persist in learning, grasping the backbone, grasp the
45、practice, grasp the opportunity. Catch club, effective way to grasp the network, with the group of cadres, young students and young backbone fronts as the focus, to promote the work of the armed youth theory to develop in depth, to help the youth continue to firm ideals and beliefs, to build a power
46、ful spiritual pillar. To carry out the study and implementation of the partys sixteen session of the five Eight plenary session of the two plenary session of the Central Committee and the party spirit, to the citys Youth League members thinking into the spirit of the meeting, to achieve the goal of
47、national consciousness and XX economic and social development in 11th Five-Year period. Contribute to help and guide the youth to a profound understanding of the significance and main task of building a socialist harmonious society, actively join the construction of socialist harmonious society.(two
48、) to strengthen the ideological and moral construction of teenagers. Thoroughly implement the central spirit of the document No. 8, No. 16 and the program for Improving Civic Morality to minors and students as focus groups, to strengthen and improve the ideological and moral construction of minors and the ideological and political education of college students. Make full use of the spirit and the spirit of the Three Gorges migrants Hongyan XX unique the use of educational resources, school, into the team, the league, to join the party, adult occasions, extensive Hongyan spirit gene