128m提篮拱先梁后拱支架设计与施工.docx

跨沪宁高速公路128m提篮拱先梁后拱支架设计及施工摘要：上跨沪宁高速公路提篮拱桥，全长132m，计算跨长128m，拱肋平面内矢高25.6m的下承式钢管混凝土提篮式系杆拱桥，本文着重介绍该桥在上跨沪宁高速公路高架桥的支架设计及施工措施。 关键词： 128m提篮拱支架施工设计 abstract: the cross on the shanghai-nanjing expressway basket handle arch, the total length is 132m, calculation span length is 128m, arch vector high 25.6m basket cfst arch bridge, this article focuses on the stent design and construction measures of the bridge in the cross-shanghai-nanjing high-speed highway viaduct.key words: 128m x arch bracket construction design 1引言 沪宁高速公路高架桥，为四座并线高架桥，该桥高约12m，为t型预应力钢筋砼梁，其上跨沪昆铁路。而京沪高铁128m提篮拱上跨该四座高架桥，且紧邻沪昆铁路，桥位处下有通信光缆，铁路专用电缆，上海市西气东输主管道，施工条件相当复杂。作为该桥的支架设计受特殊条件制约明显，故如何因地制宜采用合理地解决方案为该桥施工支架设计的重点所在。 2概述 京沪高速铁路上跨沪宁高速公路提篮拱桥，全长132m，计算跨长128m，矢跨比为f/l=1/5，拱肋平面内矢高25.6m，拱肋采用悬链线线形，上部为1-128m钢管混凝土拱简支梁。拱桥系梁按整体箱形梁布置，采用单箱三室预应力混凝土箱形截面，桥面箱宽17.8m，梁高2.5m。128m跨径钢管拱肋在横桥向内倾，形成提篮拱，吊杆布置成斜吊杆，两拱肋之间设钢管横撑，锚固于箱梁边腹板。拱肋管内压注c55级微膨胀混凝土。 3工艺特点 （1）、本方案采用的临时墩刚性支撑结合贝雷梁作为跨越高速公路支架形式，对于跨越既有通车高架桥，工艺相对可靠和成熟。 （2）、贝雷片采用分组吊装方式，可缩短吊装和占道时间，能最大程度减小对高速公路通车的影响。 （3）、临时支墩跨度大，最大跨度16m，跨中无任何支撑，采用单排贝雷，不影响车辆通行，对于交通量大，且较难进行持续封闭的高速公路来讲，具有显著的社会经济效益。 （4）、由于桥梁间隙仅为34cm，按照常规传统施工工艺，钢管立柱满足不了施工和设计要求，采取型钢立柱解决该难题。 4 现浇支架比较 按照传统施工工艺来讲，跨桥部分施工支架由于受场地空间条件限制，只能采用临时刚性支墩结合贝雷架的方式进行设计，而此刚性支墩采用何种形式，应值得重点考虑，笔者在施工支架设计过程中，也做了一系列比选，包括对高架桥部分t梁翼板进行局部破除，以提供钢管立柱架立的空间，但该方案须经相关产权、设计、交管、路政等各部门积极配合和审批后方能进行，所需时限太长，且破除施工、交通维护、及桥梁恢复的费用较大，经济性较差。 在此基础上，需要重新在结构设计角度减小施工难度，降低施工成本。后经理论计算，最终确定利用型钢作为临时墩支撑，上设型钢分配梁及贝雷梁进行纵向跨越。 5施工支架设计及施工 5.1 现浇梁支架结构 现浇梁施工采用落地式钢管支架体系，基础采用钻孔桩，根据现场空间及地质条件选用恰当桩径及桩长，并设置地系梁，加强基础的整体稳定性，地系梁适当配筋设计，通过预埋钢板与立柱连接，立柱共分为两部分，不受桥梁空间限制的采用钢管立柱（800 12mm无缝钢管），受桥梁间隙影响较大的采用hw350型钢立柱；平联剪刀撑采用20，16；平联剪刀撑与钢管立柱进行现场焊接。 柱顶设置2i50a型钢作为横梁，其上方布置贝雷梁，考虑到标准支撑架的尺寸，成组布设间距为0.45m，人行通道处所承受荷载较小，间距为90cm，自制联系角钢撑杆，横向共44排贝雷片。贝雷梁上方铺设间距0.5m的i10工字钢作为分配梁，横梁底模板面板采用15mm的竹胶板，系梁横向两侧各设置1.5m宽操作平台。 施工支架横桥向布置9根钢管立柱，柱顶标高由桥面标高反推算求得，柱底高程根据原地面情况，统一设置为2.4m，高度方向布置两排平联剪刀撑，间距6.0m，第一道剪刀撑中心距贝雷架底面1.5m。 考虑到该支架高度较高，近20m，且部分排架跨径相对较大，部分为型钢立柱支撑，对其稳定性要求较高，故采用300mm钢管作为支架纵向联系。 现浇支架横断面布置图如下。 5.2 支架检算 按照施工工序考虑，该支架施工设计分析存在两种工况： 工况1：系梁砼浇筑时，支架承受梁体自重、贝雷及型钢自重、模板自重、施工荷载、浇筑混凝土时的冲击荷载。 工况2：拱肋砼压注时，按照最不利条件考虑，支架承受拱管及拱肋砼自重、拱肋支架自重，及工况1包括的各种荷载，不考虑砼梁的抗弯和抗压能力。 由于该支架跨越国内公路运输最为繁忙的沪宁高速，支架设计不能单纯考虑其经济性，更应注重其安全性，排除影响支架稳定的不确定因素，支架设计时，还应加大支架的安全储备。 强度检算：包括面层分配梁、贝雷片、工字钢横梁、钢管立柱以及地系梁的强度检算； 挠度检算：包括分配梁、贝雷片、工字钢横梁的挠度验算。 整体稳定检算：大型支架的整体稳定性检算，计算相对复杂，可采用sap2000或midas软件进行建模和计算，但建模过程相对繁琐，涉及的单元和节点数量庞大，对计算机的要求相对很高。采用传统手算时，都是通过单桩轴压稳定来确保整体稳定，故单桩稳定满足要求时，整体稳定相对较为安全，安全储备也较大。 由于桥位所处上海，支架对台风的抵抗能力要有所考虑。模板和支架的迎风面积、支架高度、计算风压、风力系数对支架的影响，应予以计算。另外受外界因素影响以及工人操作水平的制约，钢管轴压稳定问题以及抗偏心问题也应重点考虑和详细计算。 5.3 立柱施工 该支架施工重点及难点为跨桥部分型钢立柱的吊装，桥梁进行依次封闭，型钢立柱通过挂车运至桥上指定位置，吊装施工采用25t汽车吊于高架桥上进行整体吊装，一次就位。施工时，采用吊垂球的方式控制其垂直度，并且严格控制平面位置，防止立柱与既有高架桥贴连，以避免车辆通过引起梁体震动冲击现浇支架。 由于该立柱结构安装采用限时封闭高速公路，因此人员、机械、材料以及小型机具的准备必须要充分考虑周全，施工组织管理统一。 5.4 贝雷梁安装施工 贝雷片于空阔场地拼装完成，转运至桥位处，采用2片一组进行吊装，减少现场安装时间和安全隐患。 5.5 支架整体预压 （1）支架预压 支架预压在系梁底模板下设方木铺设完毕后进行，预压材料采用砼预制块作为预压体，均布在方木上，预压重量等于梁体重量的1.1倍，加压顺序与浇筑混凝土顺序一致。从理论角度出发，预压时，可选取有代表性的、最不利区域的方式预压，即支架最大跨度范围进行预压，能够满足施工要求。 （2）支架变形观测 支架稳定及变形测设主要分为两个位置进行，一是箱梁底方木上，二是地系梁顶面。通过两个位置的沉降变形来进行综合分析，由于支架基础设计采用钻孔桩，从观测数据来看，基础基本无沉降。 方木上方点位测设时，沿梁纵向范围内，每隔5.0m 设置一排测点，横向断面设三个测点，并做编号。第一次观测在预压前进行，记录好标高，作为沉降观测的基准。加载过程中，宜分四级进行，即25%、50%、75%和100%的加载总重，每级加载后均静载1小时，测量各阶段的支架沉陷量，堆载完成后再测量一次，其余为每隔3小时测量一次，连续观测3天，若观测数据基本不变，即绘制沉降曲线，计算出支架沉降量，作为调整模板标高的有效数据。 （3）支架压重的卸载 支架沉降稳定后，不再有沉降，然后开始卸载。 （4）调整支架标高调整 预压后，支架已基本消除预压荷载作用支架部位及各钢构件的间隙及非弹性变形。预压卸载后的回弹量即是箱梁在混凝土浇注过程的下沉量，因此，模板顶的标高值最后调整为设计标高值加预拱值加预压回弹量。由于本桥支架为刚性支架，采用加塞木条及木块的方式调整底模板标高。 （5）预拱度设置 由于箱梁在浇筑施工和卸架后，会发生一定的下沉和产生一定变形，因此，为使箱梁在卸架后能获得满意的设计线形，须在模板安装的时候，按设计要求设置一定数值的预拱度。预拱度设在箱梁跨径的中点，以中点预拱度为最大值，以梁的两端为零(即墩支承点为零)。预拱计算公式为:f=f1+f2，其中，f:支架弹性变形，f2:梁体挠度。 5.6 拆除临时墩支架、贝雷架 拆除钢管桩临时支架，同时进入桥面附属设施安装阶段。贝雷片拆除时，首先于钢管顶端割出槽口千斤顶配合进行落架，后通过卷扬机将其成组顶拖至系梁外侧，利用25t吊车以及塔吊吊落，运出施工现场。 6 结束语 （1）钢管和型钢的连接与拆除，需要现场电焊、气割工作量较大，对操作工人的素质要求较高，由于支架高度较高，施工及检查难度较大。 （2）由于通车净空受限，该支架在贝雷上方并未设置碗扣架，若条件允许，建议临时墩贝雷上方还应尽量设置碗扣架。一方面可以方便有效地调整底模板预拱度，另一方面可大大降低卸架难度。 （3）对于跨路现浇梁支架来讲，若地质情况满足，可尽量采用钢管柱排架与碗扣支架结合的方式实施，相对来讲，钢管柱排架属刚性支架，而碗扣架属柔性支架，如何有效地采取恰当措施避免两者结合部位沉降变形不一致现象，是值得进一步探讨的问题。 （4）由于该拱桥系梁需要上跨高架桥，支架主体采用钢管桩及型钢排架墩结合贝雷承重主梁形式，梁体受力均匀，形式相对简单，承重效果明显，设备通用性好。 （5）由于本桥施工工期较紧，受邻近沪杭铁路影响，吊装条件受到极大限制，因此，采用了分段吊装方案。在一般工地，以推广采用大型吊机上桥进行分段吊装的方案，藉以减少大型设备及场地需要量，并降低施工成本。 注：文章内所有公式及图表请以pdf形式查看。 （英文版 ） Two regulations promulgated for implementation is in the party in power for a long time and the rule of law conditions, the implementation of comprehensive strictly strategic plan, implementation in accordance with the rules and discipline to manage the party, strengthen inner-party supervision of major initiatives. The two regulations supporting each other, the adhere to a positive advocate, focusing on morality is of Party members and Party leading cadres can see, enough to get a high standard; around the party discipline, disciplinary ruler requirements, listed as negative list, focusing on vertical gauge, draw the party organizations and Party members do not touch the bottom line . Here, the main from four square face two party rules of interpretation: the first part introduces two party Revised regulations the necessity and the revision process; the second part is the interpretation of the two fundamental principles of the revision of laws and regulations in the party; the third part introduces two party regulations modified the main changes and needs to grasp several key problems; the fourth part on how to grasp the implementation of the two regulations of the party. and revised the necessity and revised history of the CPC Central Committee the amendment to the Chinese Communist Party members and leading cadres honest politics several guidelines and column 1 by 2015 to strengthen party laws and regulations focus. Two party regulations revision work lasted a Years, pooling the wisdom of the whole party, ideological consensus, draw historical experience, respect for the wisdom of our predecessors, which reflects the unity of inheritance and innovation; follow the correct direction, grasp the limited goals, adhere to the partys leadership, to solve the masses of the people reflect a focus on the problem. The new revision of the and , reflects the partys 18 and the eighth session of the third, the spirit of the fourth plenary session, reflecting the experience of studying and implementing the General Secretary Xi Jinping series of important speech, reflects the partys eighteen years comprehensive strictly practice. (a) revised two regulations of the party need of in based on revised, the promulgation and implementation of January 2010, to strengthen the construction of the contingent of leading cadres play an important role. But with the party to manage the party strictly administering the deepening, has not been able to fully meet the actual needs. Content is too complicated, eight prohibition, 52 are not allowed to hard to remember, and also difficult to put into practice; the second is concisely positive advocated by the lack of prohibited provisions excessive, no autonomy requirements; the third is banned terms and discipline law, both with the party discipline, disciplinary regulations repeat and Criminal law and other laws and regulations repeat; the fourth is to clean the theme is not prominent, not for the existing problems, and is narrow, only needle of county-level leading cadres above. is in 1997 based on revision, in December 2003 the promulgation and implementation, to strengthen the construction of the party play very important role. Along with the development of the situation, which many provisions have been unable to fully meet the comprehensive strictly administering the practice needs. One is Ji law, more than half of the provisions and criminal law and other countries laws and regulations Repetition; two is the political discipline regulations is not prominent, not specific, for violation of the party constitution, damage the authority of Party Constitution of misconduct lack necessary and serious responsibility to pursue; third is the main discipline for the leading cadres, does not cover all Party members. Based on the above situation, need to and the two is likely to be more relevant regulations first amendment. By revising, really put the authority of Party discipline, the seriousness in the party tree and call up the majority of Party members and cadres of the party constitution of party compasses party consciousness. (II) two party regulations revision process the Central Committee of the Communist Party of China attaches great importance to two regulations revision . Xi Jinping, general books recorded in the Fifth Plenary Session of the eighth session of the Central Commission for Discipline Inspection, on the revised regulations made clear instructions. According to the central deployment, the Central Commission for Discipline Inspection from 2014 under six months begin study two regulations revision. The Standing Committee of the Central Commission for Discipline Inspection 4 review revised. Comrade Wang Qishan 14 times held a special meeting to study two regulations revision, amendment clarifies the direction, major issues of principle, path and target, respectively held a forum will listen to part of the province (area) secretary of the Party committee, Secretary of the Discipline Inspection Commission, part of the central ministries and state organs Department The first party committee is mainly responsible for people, views of experts and scholars and grassroots party organizations and Party members. Approved by the Central Committee of the Communist Party of China, on 7 September 2015, the general office of the Central Committee of the Party issued a notice to solicit the provinces (autonomous regions, municipalities) Party, the central ministries and commissions, state ministries and commissions of the Party (party), the General Political Department of the military, every 3 people organization of Party of two regulations revision opinion. Central Commission for Discipline Inspection of extensive solicitation of opinions, careful study, attracting, formed a revised sent reviewers. In October 8 and October 12, Central Committee Political Bureau Standing Committee and the Political Bureau of the Central Committee After consideration of the two regulations revised draft. On October 18, the Central Committee of the Communist Party of China formally issued two regulations. Can say, two laws amendment concentrated the wisdom of the whole party, embodies the party. Second, and revision of the basic principles of two party regulations revision work and implement the partys eighteen, ten eight plenary, the spirit of the Fourth Plenary Session of the Eleventh Central Committee and General Secretary Xi Jinping important instructions on the revised and , highlighting the ruling party characteristics, serious discipline, the discipline quite in front of the law, based on the current, a long-term, advance as a whole, with Bu Xiuding independent and . Main principle is: first, adhere to the party constitution to follow. The constitution about discipline and self-discipline required specific, awaken the party constitution of party compasses party consciousness, maintaining the authority of the constitution. General Secretary Xi Jinping pointed out that no rules, no side round. Party constitution is the fundamental law, the party must follow the general rules. In early 2015 held the eighth session of the Central Commission for Discipline Inspection Fifth Plenary Session of the 16th Central Committee, Xi Jinping again pointed out that constitution is the party must follow the general rules, but also the general rules. the revision of the and is Method in adhere to the regulations established for the purpose of combining rule of virtue is to adhere to the party constitution as a fundamental to follow, the constitution authority set up, wake up the party constitution and party rules the sense of discipline, the party constitution about discipline and self-discipline specific requirements. 4 second is to adhere to in accordance with the regulations governing the party and the party. The Party of rule of virtue de, mainly refers to the partys ideals and beliefs, excellent traditional style. The revised the closely linked to the self-discipline, insisting on the positive initiative, for all members, highlight the vital few, emphasized self-discipline, focusing on the morality, and the majority of Party members and the ideological and moral standards. The revised Ji method separately, Ji, Ji Yan to Method, as a negative list, emphasizing the heteronomy, focusing on vertical gauge. Is this one high and one low, a positive reaction, the strict party discipline and practice results transformation for the integration of the whole party to observe moral and discipline requirements, for the majority of Party members and cadres provides benchmarking and ruler. Third, insist on to. In view of the problems existing in the party at the present stage, the main problems of Party members and cadres in the aspect of self-discipline and abide by the discipline to make clearly defined, especially the partys eighteen years strict political discipline and political rules, organization and discipline and to implement the central eight provisions of the spirit against the four winds and other requirements into Disciplinary provisions. Not one pace reachs the designated position, focusing on in line with reality, pragmatic and effective. After the revision of major changes, major changes in the and modified and needs to grasp several key problems (a) adhere to according to regulations governing the party and party with morals in combination, for at the present stage, the leadership of the party members and cadres and Party members in existing main problems of self-discipline, put forward principles, requirements and specifications, showing Communists noble moral pursuit, reflected at all times and in all over the world ethics from high from low 5 common requirements. One is closely linked to the self-discipline, removal and no direct relation to the provisions of . the second is adhere to a positive advocate, eight prohibition 52 are not allowed to about the content of the negative list moved into synchronization amendment . Three is for all the party members, will apply object from the leadership of the party members and cadres to expand to all Party members, fully embodies the comprehensive strictly