恩聚羧酸系减水剂在高性能混凝土中的应用.doc

Xiaoping theory and the important thought of the three represents and the scientific Outlook on development. Such changes were made, is conducive to implementing the innovation of Marxism in China, especially the scientific concept of development the strategic task of arming the whole party, play grass-roots organizations in promoting the scientific Outlook on development into the grass-roots level, and to implement the important role. Third, how to use the contents of the new Constitution guiding party building through studying the essence of the new Constitution, the flexible application of the essence of the Constitution in party building, and I think the key to grasping the following: to catch the discipline, focus on strengthening the partys rules and regulations binding. To strictly observe and carry out the partys political discipline, ensure the centralism and unity of the whole party. Party cadres, especially leading cadres, both doers, but also have a strong sense of political awareness to dry line, line, not lack of ability to work, become a talker; hard work isSkill, political direction, unable to understand when confused. Flag of the CPC Central Committee and the Committees requirements into Departments request, to a holistic and concerted efforts, subject to the overall situation. Second, cadres and strive to play an exemplary role of party members and cadres of hardworking and clean, emphasizes lead, shift, led. Lead is to adhere to set an example, to lead by example, deal with the relationship between individuals and parties, real lead role shift is in order to strengthen the sense of responsibility, creating a fighting force; lead is to adhere to strict requirements, strict management and strict supervision. Three catch basis and strive to enhance the combat effectiveness of the party organization. To according to Constitution on grass-roots party of requirements, to implementation good basic system, for members for, regardless of party positions has more high, administrative terms has more big, any when are to has Organization concept, active participate in organization activities, consciously accept party of supervision; to do based sex work, management good members, service good members, grass-roots party to using members organization received turned, and members thought reported, and party of Conference and dues pay, opportunities, master members of basic situation, care members life. Four to focus and work hard to resolve. Comrades, the above is what I give you guidance in the new Constitution. Hope every Member of the party to pass the tutor, deepen our understanding of the Constitution in the partys guiding ideology advancing with the times, consciously link their own thinking and practice, after careful study, read and carefully understand, think, relate, apply what they have learned. Not only runs through the mass line of the party Constitution to learn the new educational practice all the time, but also to harvest as a good starting point to learn, study and work to do better in the future, and strive to create a new situation for school education contribute their恩聚羧酸系减水剂在高性能混凝土中的应用1、工程概况我单位承建的青岛双积公路高红段工程第一合同段位于青岛市城阳区，本段施工范围为K0+000-K7+650,其中路基长度6.547公里,桥梁1.103公里，其中C35混凝土20238m，C40混凝土10193m，C50混凝土19968m。沿线的地质主要为软土、盐渍土等，路线所经区域主要为滨海地带，地势低平，地层主要为人工填土、海基层软土、淤泥质软粘土。由于受到地形、地质结构、水文、通航、航空条件等因素的制约，施工条件复杂，施工技术难度大。特别是桥梁结构处于北方微冻地区的近海环境，是作用等级从中等程度（C级）至严重程度（D级）的氯盐腐蚀环境，为了确保结构使用寿命达到100年的设计年限，必须根据胶州湾的环境气候特征，设计满足设计与施工技术的海工高性能混凝土。因此，本工程应用了NOF-AS聚羧酸系高性能减水剂，针对该减水剂在应用中遇到的技术问题，笔者进行了分析和总结，供同类工程借鉴和参考。2、聚羧酸系高性能减水剂的发展与应用现状日本于1981年开始研制聚羧酸系高性能减水剂，并于1986年将产品成功打入市场。目前，聚羧酸系高性能减水剂的研究仍以日本发展较快，到2001年为止，聚羧酸系高性能减水剂用量在AE减水剂中已超过了80%，主要生产厂商有日本的花王、竹本油脂、日本制纸、藤泽药品等。美国高效减水剂的发展比日本晚，聚羧酸系高性能减水剂目前美国正从萘系、蜜胺系减水剂向聚羧酸系高性能减水剂发展，主要生产厂家有MASTE公司、GRACE公司等。另外国外还有意大利的MADI公司、瑞士SIKA公司等生产。国内对聚羧酸系高性能减水剂的研究起步较晚，但发展较快，上海磁悬浮铁路高精度轨道梁的制作、东海大桥海工混凝土、洋山深水港集装箱道堆混凝土、宜万铁路宜昌长江大桥以及杭州湾大桥、青岛海湾大桥等工程中已得到成功的应用。3、聚羧酸系高性能减水剂的性能特点混凝土外加剂的研究与生产已趋向朝着高性能、无污染方向发展。具有梳形分子结构的聚羧酸系高性能减水剂因其减水率高、保坍性能好、混凝土早期强度高、保塑性好、水化热温升平稳、收缩小、掺量低、无污染、缓凝时间少、成本低等显著特点，适宜配制高强超高强混凝土、高流动性及自密实混凝土,成为国内外混凝土外加剂研究开发的热点。4、聚羧酸系减水剂在青岛双积公路项目海工高性混凝土中的应用4.1海工高性能混凝土的设计指标青岛双积公路海工高性能混凝土强度及耐久性指标，见表1海工高性混凝土强度等级及耐久性要求指标表1构件类型环境分类混凝土强度等级84d渗透性能28d抗冻性能Cl-扩散系数10-12m2/s电通量C快冻法（循环次数）桩基-CC352.01500/承台-CC401.51000/墩身-CC401.51000/预制箱梁-DC501.510003004.2原材料选择(1)水泥：选用青岛山水P.I52.5硅酸盐水泥，水泥中氯离子含量检测结果为0.018%，低于0.03%的要求。(2)粉煤灰：使用潍坊明华I级粉煤灰。(3)矿粉：使用青岛家樑S95矿粉。(4)细集料：选用颗粒坚硬、强度高、耐风化的青岛大沽河天然河砂。(5)粗集料：选用胶南宝山510mm，1020mm石灰岩碎石，比例为30%：70%。(6)外加剂：NOF-AS聚羧酸系高性能减水剂，减水率达25以上。(7)水：拌和用水为生活用水。4.2配合比设计优化高性能混凝土中因胶凝材料用量大,水灰比小，掺入聚羧酸盐系高性能减水剂等，导致混凝土拌含物粘性过大,出现“抓底”现象,因此，砂率可适当高一些,经试验，确定砂率40%。掺粉煤灰的混凝土早期强度较低,且随粉煤灰掺量的增加而降低辐度增大,但是后期强度增长潜力较大，考虑到预制箱梁需要7天达到张拉强度（45Mpa），故粉煤灰掺量不宜过大。为了保证混凝土早期强度，满足张拉要求，控制混凝土的水化热过高引起开裂，混凝土设计过程中考虑磨细矿粉取代部分水泥。经验证，水泥:粉煤灰:矿粉=60%:15%:25%时，混凝土和易性、使用性及耐久性等均可满足施工和设计要求。小石（510mm）:大石（1020mm）30：70连续级配，容重最大。4.3海工高性能混凝土拌合物检测及施工质量控制为了保证箱梁预制质量,要求混凝土具有良好的流动性、粘聚性和使用性。现场施工过程中,混凝土拌合物有时非常粘稠,干涩,收面后表面像胶一样，这样的混凝土使用性就很差；有时出拌合站后坍落度靠下限,可罐车运到现场后,就接近上限；有时从罐车放到料斗并不稀，可吊送到梁面后异常稀，并且会出现大量浮灰或流浆，这些现象给施工质量造成了一定的困难。因此，采取对坍落度和扩展度双控制，保证坍落度180220mm,同时满足扩展度420520mm。加强原材料质量控制，严格控制砂石料含泥量，保证洗好的碎石有足够的脱水时间，施工过程中根据适时检测的砂石含水量，调整砂石用量，在保证水灰比不变的条件下，只要满足施工、强度和耐久性要求，减水剂掺量也根据实际情况进行动态控制。4.4海工高性能混凝土强度及耐久性混凝土施工质量控制，一方面要保证良好的工作性，满足施工要求；另一方面，硬化后的混凝土要满足设计强度和耐久性要求。青岛双积公路预制箱梁混凝土，硬化后要保证抗压强度和弹性模量满足7天张拉要求，还要保证28天抗压强度和弹性模量。本工程所处的胶州湾在一般年份，12月下旬开始结冰，2月中旬消融，最冷月平均气温为-0.5，属于微冻地区，因而，对混凝土的抗冻性要求高。此外，为了控制海水中氯盐腐蚀，必须要求混凝土有良好的抗氯离子渗透性。混凝土强度及耐久性检测成果见下表(2010年某一时段进行统计)。5、聚羧酸系高性能减水剂在海工高性混凝土应用中的若干技术问题5.1混凝土表面出现浮灰由于聚羧酸系高能减水剂具有不同于萘系减水剂的特性,使掺有级别高的级粉煤灰和这类减水剂的拌合物,尤其是当粉煤灰掺量较小、水胶比变大的拌合物更易于出现泌水、离析分层、大量气泡外冒的现象。致使混凝土表面出现浮灰，影响拉毛收面质量和外观。5.2含气量掺聚羧酸系高能减水剂的拌合物含气量通常较萘系的大,振捣后一段时间内表面还有气泡外冒，气泡孔径也较大,这是由该系列减水剂的组分所决定的。不能说该外加剂混凝土引气效果好，只能说含气量大，保气性差，因为所谓的引气是指引入而不是引出，不能犯了概念错误。5.3难以控制合适的加水量和外加剂掺量掺聚羧酸系高能减水剂的混凝土对温度、用水量、拌和时间、骨料品质级配及细骨料含泥量等较为敏感。控制不好，就会出现混凝土拌合料异常干涩、无法卸料，更甭提浇注使用；混凝土拌合物浇注后,集料与浆体分层严重；混凝土拌合物泌水量和流浆异常惊人。因此，控制合适的用水量和控制外加剂的掺量极为重要。5.4水泥与聚羧酸系减水剂适应性由于水泥矿物组成、细度等对聚羧酸系减水剂的效应，对某些水泥来说，与聚羧酸系减水剂适应性十分明显。工程初期我们做配合比的时候,使用了多个水泥厂家与外加剂厂家来调试,有时候用相同的配合比,只是使用不同厂家的外加剂与水泥，混凝土拌合物非常粘稠，粘的时候用铁锨铲着都非常费力,混凝土拌合出锅后过5分钟就不会流动，显得很“死”。经过多次的试验，最终选取了融合的最好的外加剂与水泥。6、聚羧酸系减水剂在工程应用中必须注意的问题6.1严格控制振捣半径和振捣时间6.2加强初期养护，严防开裂海工高性能混凝土胶材料用量大，尤其当表面出现浮灰和流浆时，加强初期养护，严防混凝土早期收缩开裂是关键。6.3施工管理单位应与混凝土制备者和外加剂供应者密切合作6.4避免聚羧酸系减水剂与铁制材料接触由于聚羧酸高效减水剂产品常呈现酸性与铁制品长期接触会发生缓慢反应，甚至使产品色泽变深、变黑，导致产品性能下降，建议采用聚乙烯塑料桶或不锈钢储存，才能保证产品储存的稳定性。6.5坚决避免其它品种外加剂的混入聚羧酸系高效减水剂严禁与萘系高效减水剂及复配产品混合应用。若混合的话，混凝土拌合物的良好流动性随之消失，也直接影响可泵性和混凝土的强度。6.6聚羧酸系高效减水剂的超掺量和砂石含水量变化影响问题当超量时，会产生离析、泌水、板结及含气量过大等不良现象，所以拌制掺聚羧酸系高效减水剂的混凝土时，其计量设备和计量精度必须准确和灵敏。该外加剂对用水量、砂石级配、环境温湿度等较为敏感，在保证混凝土理论配合比基本不变情况下，根据生产过程中砂石含水量，适时调整砂石用量和拌合用水量。并严格控制外加剂和拌合水计量，动态调整外加剂掺量，防止超掺量，控制浮灰流浆，保证混凝土粘聚性、流动性和可泵性。6.7正确面对聚羧酸系减水剂与水泥/掺合料适应性问题聚羧酸系高性能减水剂依然存在与水泥适应性问题，水泥、粉煤灰和矿粉组合使用与聚羧酸高效减水剂适应性，也应引起重视。聚羧酸系高效减水剂的应用，仅做检验净浆流动度及砂浆减水率是不够的，必须试拌混凝土，混凝土的适应性成功才算是真正的成功。7、结语聚羧酸系高性能减水剂具有减水率高、流动性好、增强性好、保坍性能优良等综合性能，可以减少混凝土的收缩和提高混凝土的耐久性。这些在青岛双积公路海工高性能混凝土应用中得到充分的体现。工程技术人员应正确面对聚羧酸系高性能减水剂在应用中出现技术问题，进行认真的分析和总结，找出解决问题的方法，扬长避短，充分利用聚羧酸外加剂带来的优良性能，这是提高建设工程质量的关键。参建了银河广场、大沽南路、外环辅道、津南污水处理厂、天津大学新校区水处理、北闸口泵站、团泊片区项目等工程，多次被评为集团级二星级岗位能手、技术明星等称号Thank you very much. -The Constitution Party rules address the series really is a qualified party members earlier this year, all party members to the Central series of party rules, and address of the party Constitution, be qualified party members learn education is an important decision. XI Jinping, Secretary General chaired a Politburo meeting in February, were devoted to educational programmes and made an important speech recently personally approved specific programmes, many important instructions. On April 6, 13th, 15th, the Central and autonomous regional party Committee, the municipal party Committee held educational symposium, and related matters For specific deployment, we held on March 4, Hongshan district party working Conference also proposed to carry out this activity. All together this forum today, main purpose is to study and implement in depth General Secretary XI Jinping on two important instructions for learning education, studying and implementing the Central and autonomous region Party Committee and municipal party Committee two spiritual education Symposium, arrangements for district-wide learning education. The following, I would like to stress four points, mainly talk about learning and doing issue, and strive to make people really figure out why, what to learn and how they learn, what to do, how to do it, eventually reached little success, is also leading a lesson in party lecture. After both leaders and the cadres, regardless of Branch Secretary or an ordinary party member, to implement certain boundaries education give a Party lecture requirement, practice speaking, speak much fanfare, innovation way, down to Earth, ensuring educational success. First, you know, pay special attention to education and to resolutely overcome sluggish thinking, and boredom two study and education, possibly quite a few comrades, saying education every year, almost every year fool fool, I feel that with this in mind who may be many. If carrying this idea in mind, what does that tell, how the political consciousness is not strong and not see the pulse of the situation, no, the Rip van Winkle, lost or confused in the end do not know whats going on. To realize two a learning practice activities and education is the education of the partys mass line, three-three special education was another important practice in implementing the requirements of strictly administering the party. Comrade XI Jinping pointed out: the deployment of doing education, is to promote the inner-party education from critical few their expansion into the vast number of party members, extending from the concentrated education to regular education. After 18, Central Committee of the party must handle party, strictly administering the party, and has carried out the partys mass line education practice and three-three special education, but focus on the leading cadres above the county level. The two study and education, is carried out in the whole party and all the party members. This is implemented strictly administering the party, an important measure to