短肢剪力墙和异形柱的区别.doc

短肢剪力墙和异形柱的区别 摘 要：对异形柱与短肢剪力墙结构设计中的一些问题，如计算方法、异形柱受力性能及其轴压比控制、短肢剪力墙结构中转换层的设置高度及框支柱等进行探讨，提出建议，供结构设计人员参考。 关键词：异形柱；短肢剪力墙；结构设计现代住宅建筑要求大开间，平面及房间布置灵活、方便，室内不出现柱楞、不露梁等。异形柱与短肢剪力墙结构能较好地满足现代住宅建筑的要求，因而逐渐得到了推广应用。目前，现行国家规范或规程中尚未给出有关异形柱与短肢剪力墙结构设计的条款，因此，结构设计人员在设计中常会遇到一些规范或规程尚未论及的问题，需要设计人员积累经验，利用正确的概念进行设计。本文旨在对异形柱与短肢剪力墙结构设计中的一些问题进行探讨，提出个人看法，供结构设计人员参考。1、异形柱结构型式及其计算异形柱结构型式有异形柱框架结构、异形柱框架剪力墙结构和异形柱框架核心筒结构。异形柱结构自身的特点决定了其受力性能、抗震性能与矩形柱结构不同。由于异形柱截面不对称，在水平力作用下产生的双向偏心受压给承载力带来的影响不容忽视。因此，对异形柱结构应按空间体系考虑，宜优先采用具有异形柱单元的计算程序进行内力与位移分析。因异形柱和剪力墙受力不同，所以计算时不应将异形柱按剪力墙建模计算。当采用不具有异形柱单元的空间分析程序（如TBSA 5.0）计算异形柱结构时，可按薄壁杆件模型进行内力分析。对异形柱框架结构，一般宜按刚度等效折算成普通框架进行内力与位移分析。当刚度相等时，矩形柱比异形柱的截面面积大。一般，比值（A矩A异）约在1.10-1.30之间1。因此，用矩形柱替换后计算出的轴压比数值不能直接应用于异形柱，建议用比值（A矩A异）对轴压比计算值加以放大后再用于异形柱。对有剪力墙（或核心筒）的异形柱结构，由于异形柱分担的水平剪力很小，由此产生的翘曲应力基本可以忽略，为简化计算，可按面积等效或刚度等效折算成普通框架剪力墙（或核心筒）结构进行内力与位移分析。按面积等效更能反映异形柱轴压比的情况，且面积等效计算更为简便。但应注意，按面积等效计算时，须同时满足下面两式：（1）A矩=A异；（2）b/h=（Ix异Iy异）1/2式中，A矩、A异分别为矩形柱和异形柱的截面面积；b、h分别为矩形截面的宽和高；Ix异 、Iy异分别为异形柱截面x、y向的主形心惯性矩。一般，按面积等效计算时，矩形柱的惯性矩比异形柱的小。但对有剪力墙（或核心筒）的异形柱结构，计算分析表明2，按面积等效与按刚度等效的计算结果是接近的。异形柱的截面设计，可根据上述方法得出的内力，采用适合异形柱截面受力特性的截面计算方法进行配筋计算。 2、短肢剪力墙结构及其计算短肢剪力墙结构是适应建筑要求而形成的特殊的剪力墙结构。其计算模型、配筋方式和构造要求均同于普通剪力墙结构。在TAT、TBSA中，只需按剪力墙输入即可，而且TAT、TBSA更适合用来计算短肢剪力墙结构。TAT、TBSA所用的计算模型都是杆件、薄壁杆件模型，其中梁、柱为普通空间杆件，每端有6个自由度，墙视为薄壁杆件，每端有7个自由度（多一个截面翘曲角，即扭转角沿纵轴的导数），考虑了墙单元非平面变形的影响，按矩阵位移法由单元刚度矩阵形成总刚度矩阵，引入楼板平面内刚度无限大假定减少部分未知量之后求解，它适用于各种平面布置，未知量少，精度较高。但是，薄壁杆件模型在分析剪力墙较为低宽、结构布置复杂（如有转换层）时，也存在一些不足，主要是薄壁杆件理论没有考虑剪切变形的影响，当结构布置复杂时变形不协调。而短肢剪力墙结构由于肢长较短（一般为墙厚的5-8倍），本身较高细，更接近于杆件性能，所以，用TAT、TBSA计算短肢剪力墙结构能较好地反映结构的受力，精度较高。对设有转换层的短肢剪力墙结构，一般都只是将电梯间、楼梯间、核心筒和一少部分剪力墙落地，其于剪力墙框支。框支剪力墙是受力面向受力点过渡，由于薄壁杆件的连接处是点连接，所以用薄壁杆件模型不能很好地处理位移的连续和力的正确传递。因此，带有转换层的短肢剪力墙结构宜优先采用墙元模型软件（如SATWE）进行计算。当然，从整体上的内力（特别是下部支承柱的内力）分布情况来看，如果将剪力墙加以适当的处理，还是可以用TAT、TBSA对结构进行整体计算的3。3、异形柱的受力性能及其轴压比控制天津大学的试验研究结果表明4：异形柱的延性比普通矩形柱的差。轴压比、高长比（即柱净高与截面肢长之比）是影响异4 短肢剪力墙结构中转换层的设置高度及框支柱在现代高层住宅的地下室和下部几层，由于停车和商业用房需较大空间，就得通过转换层来实现。在短肢剪力墙结构中，一般都只将电梯间、楼梯间、核心筒和一少部分剪力墙落地，其于剪力墙框支。据研究表明5，“框支剪力墙结构当转换层位置较高时，转换层附近层间位移角及内力分布急剧突变，内力的传递仅靠转换层一层楼板的间接传力途径很难实现；转换层下部的框支结构易于开裂和屈服，转换层上部几层墙体易于破坏。这种结构体系不利于抗震。高烈度区（9度及9度以上）不应采用；8度区可以采用，但应限制转换层设置高度，可考虑不宜超过3层；7度区可适当放宽限制。”因此，建议在6度抗震设防区，短肢剪力墙结构中转换层设置高度不宜超过5层，避免高位转换。转换层上下的层刚度比宜接近1，不宜超过2.转换层位置较高时，宜同时控制转换层下部“框支”结构的等效刚度（即考虑弯曲剪切和轴向变形的综合刚度），使EgJg与EcJc接近。EgJg为剪力墙结构的等效刚度，剪力墙结构高度取框支层的总高度，其平面和层高与转换层上部的剪力墙结构相同；EcJc为转换层下部“框支”结构的等效刚度。研究表明5，“控制转换层下部框支结构的等效刚度对于减少转换层附近的层间位移角和内力突变是十分必要的，效果也很显著。”规范对框支柱的内力、轴压比、配筋等的要求都严于普通柱。框支剪力墙结构当转换层位置较高时，如何定义框支柱，涉及到安全与经济的问题。根据圣维南原理，局部处理的影响只限于局部范围，所以当转换层位置较高（如高位转换）时，除转换层附近楼层的内力较复杂外，下面的结构受到的影响很小，应与普通框架结构基本一样，不必按框支柱处理。文献6计算了两个28层的结构，一为内筒外框架结构，一为内筒外框支结构，转换层设在18层。计算结果表明，转换层下二层的内力影响很大，下三层的内力误差最大为15%，下五层的内力已比较接近（最大误差小于10%），下八层的内力已基本一样（最大误差小于5%）。这说明框支柱只需在五层范围内加以考虑，其它层的1柱子按普通框架柱处理即可。因此，建议当转换层位置不超过五层时，转换层下的各层柱均按框支柱处理；当转换层位置超过五层时，转换层下相邻的五层柱按框支柱处理，而其它层的柱按普通框架柱处理。由于高位转换对抗震不利，所以结构设计中应尽量避免高位转换。5 短肢剪力墙结构的抗震薄弱环节及概念设计振动台模拟地震试验结果表明7，建筑平面外边缘及角点处的墙肢、底部外围的小墙肢、连梁等是短肢剪力墙结构的抗震薄弱环节。当有扭转效应，建筑平面外边缘及角点处的墙肢会首先开裂；在地震作用下，高层短肢剪力墙结构将以整体弯曲变形为主，底部外围的小墙肢，截面面积小且承受较大的竖向荷载，破坏严重，尤其“一”字形小墙肢破坏最严重；在短肢剪力墙结构中，由于墙肢刚度相对减小，使连梁受剪破坏的可能性增加。因此，在短肢剪力墙结构设计中，对这些薄弱环节，更应加强概念设计和抗震构造措施。例如，短肢剪力墙在平面上分布要力求均匀，使其刚度中心和建筑物质心尽量接近，以减小扭转效应；适当增加建筑平面外边缘及角点处的墙肢厚度（宜取250mm，对底部外围的小墙肢根据需要可取用300mm），加强墙肢端部的暗柱配筋，严格控制墙肢截面的轴压比不超过0.6，以提高墙肢的承载力和延性；高层结构中连梁是一个耗能构件，连梁的剪切破坏会使结构的延性降低，对抗震不利，设计时应注意对连梁进行“强剪弱弯”的验算，保证连梁的受弯屈服先于剪切破坏；短肢剪力墙宜在两个方向均有梁与之拉结，连梁宜布置在各肢的平面内，避免采用“一”字形墙肢；短肢剪力墙底部加强部位的配筋应符合规范要求；等。</Porganization system and working mode, the selection of a number of municipal strengthening group to build innovation and strengthen the organization 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 city's organizations at various levels. The county committee, directly under the group (work) is under the jurisdiction of grassroots League and group (total) using branch ratio shall not be less than 70%.Three, to further strengthen the group's leadership and team building(a) to strengthen the league's leadership at all levels of construction. Continue to do a good job of municipal Party Committee 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. Improve 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 selection 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 conversation, 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 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 cadres 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 the 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 village 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 elected 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 measures 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 developed 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 branch 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, basic 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 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, standardization 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 recognition 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 "feasible, 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 Youth League), grassroots organizations three young talent information database the relevant information collection system, and gradually establish the city's young people, the Communist Youth League youth talent information network, provide information platform for young talent resource development.Five, 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 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 out 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 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 party's sixteen and the spirit of the the fifth Plenary Session of the 16th CPC Central Committee implementation of the eight plenary session of the two committee, the city's 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 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 group's propaganda and ideological 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 Outlook 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 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 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 and 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 with 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 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 powerful spiritual pillar. To carry out the study and implementation of the party's sixteen session of the five Eight plenary session of the two plenary session of the Central Committee and the party spirit, to the city's Youth League members thinking into the spirit of the meeting, to achieve the goal of 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) 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 generation" theme education activities. Use of holidays and leisure time, youth organizations "three rural areas", "four communities", "four" and moral practice, guid