附建式地下室抗浮稳定性设计研究

发布时间：2018-04-16 18:36

本文选题：附建式地下室 + 上浮失效　；参考：《武汉理工大学》2013年硕士论文

【摘要】：为充分利用城市紧缺的土地资源,大量带有高层建筑的地下室正处于建设的高峰期。地下室越埋越深,由此引发了不少上浮失效事故。对近几年的抗浮失效事故统计发现,附建式地下室上浮失效事故的比例较高,主要集中在下沉庭院、地下广场等上部荷载和刚度较小的部位。国家规范对抗浮设计并没有具体的规定,各行业规范对抗浮设计中的一些问题也不统一。鉴于此,本文展开了系统地研究,主要研究内容和结论如下： 1.对地下室上浮的三种失效形态进行了统计分析,发现上浮破坏事故中局部上浮、整体上浮所占比例较少,绝大多数由局部整体上浮引起。针对三种失效形态,在设计方法上进行了研究。国家规范对局部上浮有对应设计公式,采用极限状态设计法；局部、局部整体抗浮设计多根据地方经验,采用安全系数法。地下水浮力是一种特殊荷载,抗浮设防水位下的浮力有较高的安全储备,在抗浮设计中作为标准值使局部抗浮的安全度高于整体抗浮和局部整体抗浮。 2.通过对中欧规范的比较,提出了采用抗浮桩、锚杆下的稳定性设计公式,并对安全系数的取值进行了讨论,指出我国规范在任何情况下采用同一安全系数不合理。提出当抗浮设防水位的误差较小时,抗浮桩、锚杆的抗浮稳定性安全系数Kf宜取低值,当抗浮设防水位预测较困难时Kf宜取高值,建议取值区间为1.52-1.90。 3.结合实际工程,对将附建地下室分割为若干独立单元再进行局部整体稳定性验算的方法进行了研究。通过有限元分析发现,按此方法进行设计不仅存在安全隐患而且很不经济。下沉庭院是附建式地下室的抗浮薄弱部位,抗浮设计时应加强其刚度。 4.附建式地下室局部整体抗浮稳定性设计宜考虑上部结构与抗浮构件共同作用的影响,考虑这种影响后锚杆所受拉力比按常规方式所计算的拉力减小约20%-30%。 5.对附建式地下室的局部整体抗浮稳定设计从以下两个方面进行了优化：在下沉庭院底板下增加抗浮锚杆的数量加强薄弱部位的刚度,在主楼和地下室外墙周边刚度较大范围内减少抗浮锚杆的数量。通过优化不仅提高了结构在浮力作用下的可靠性,同时减小了锚杆的数量和长度,减小了底板的变形和内力,达到了经济和安全的目的。
[Abstract]:In order to make full use of scarce land resources in the city, with a large number of high-rise building basement is at the peak of construction. The basement deeper, which caused a lot of floating failure accidents found on anti floating. Failure accident statistics in recent years, underground chamber floating failure accident higher proportion, mainly in the sunken garden, underground square upper load and stiffness of smaller parts. The national standard of anti floating design and no specific requirements, the industry norms against some problems in the design of floating is not uniform. In view of this, this paper carried out systematic research, the main research contents and conclusions are as follows:
Three kinds of failure form up 1. to the basement for statistical analysis, found that local floating floating damage accidents, the overall floating proportion is less, the vast majority caused by local integral floating. According to the three kinds of failure form, were studied in the design method. The national standard of local floating corresponding design formula, using the limit state design method; local, local overall anti floating design based on local experience, the safety coefficient method. The water buoyancy is a special load, anti floating waterlevel under the buoyancy of high security reserves, the anti floating design as the standard value of the local anti floating safety degree is higher than the overall and local overall anti floating anti floating.
2. based on the European standard, proposed the use of anti floating pile, the stability design formula under the anchor, and the safety coefficient are discussed, pointed out that China's specification in any case with the same safety factor is not reasonable. The error is smaller when the water level for prevention, anti floating pile, anchor the anti floating stability safety coefficient Kf should be low value, when the anti floating waterlevel forecast is difficult when Kf should be of high value, suggests that the value range of 1.52-1.90.
3. combined with the actual project, conducted the research on the construction of the basement will be attached to several independent unit segmentation method for computing local overall stability. Through the finite element analysis, was designed by this method is not only a security risk and is not economic. The sunken garden underground chamber is the anti floating weak parts, anti floating the design should strengthen its stiffness.
4., the overall anti floating stability design of the attached basement should consider the interaction between the upper structure and the floating members. Considering the influence, the pulling force of the anchor will be reduced by about 20%-30%. compared with the conventional way.
On the 5. part of the whole underground chamber of the anti floating stability design from the following two aspects: optimization to increase the number of anti floating anchor in the sunken garden floor to strengthen the weak parts of the stiffness, the number of anti floating anchor in the main building and the basement wall surrounding the larger stiffness range. By optimizing not only to improve the reliability of the structure under the effect of buoyancy, while reducing the number and length of anchor, reduce the deformation and internal force of the floor, to achieve the economic and security purposes.

【学位授予单位】：武汉理工大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU92

【参考文献】