止倾迫降综合纠倾法机理分析及在高层建筑纠偏中的应用

Mechanism analysis of integrated incline-rectifying and forced settlement rectification method and its application to high-rise building rectification

对一高层建筑的倾斜原因予以分析,为确保其倾斜率安全、平稳、线性地恢复到允许值,保证其沉降的长期稳定,减少纠倾过程中给多沉侧带来的拖带沉降,提高纠倾效率,提出了止倾迫降的综合纠倾方法。对用应力控制掏土量、锚索加压调控、将石灰桩与钢管桩组合使用等多重纠倾加固控制技术机理进行研究。基于摩尔库伦准则确定出塑性区范围,将掏土区划分为全塑性区和半塑性区,并得出对应的宽度,为掏土孔参数设计提供依据。通过制定科学合理的施工工序,最终保证了该高层建筑物纠倾加固工程的成功实施,使其倾斜率由纠倾前的5.52‰减小到2.54‰,满足规范及正常使用要求。采取的石灰桩与钢管桩组合桩型加固措施有效减少了纠倾带来的拖带沉降问题。提出的用应力控制掏土量的方法填补了在湿陷性黄土复合地基、复杂结构纠倾加固掏土计算方法方面的空白,对于类似建筑物纠偏设计与施工具有较强的指导意义。

Based on the analysis of the reasons which lead to building incline, in order to ensure a safe, smooth and linear regression of the incline building, and long-term stability of the building settlement, reduce towing setdement of that side having more setdement in the process, improve the efficiency of rectifying inclination, this paper provided a integrated rectification method based on incline-rectifying and forced setdement. The mechanism of multiple incline- rectifying reinforcement controlling technologies was studied, such as soil quantity control by stress, anchor cable press- ure regulation, and application of steel and lime pile. The plastic zone was determined based on the Mohr Coulomb criterion. Soil excavation zone was divided into full-plastic zone and semi-plastic zone, their corresponding width was obtained. That provided the basis for soil excavation hole parameter design. By formulating a scientific and reasonable construction process to ensure the successful implementation of the incline-rectifying reinforcement of the high-rise building,building incline rate was reduced from 5.52%0 to 2.54%0, satisfying the requirements of relevant national standards and normal service. The application of composite pile, which consists of lime pile and steel pile, effectively reduced the towing settlement problems caused by rectification. The soil excavation quantity control technology by stress filled the blank of soil excarvation quantity calculation method of collapsible loess composite foundation and complex structure. It has strong guiding significance in rectification design and construction for similar buildings.