在分析建筑物沉降恢复特点的基础上研究注浆抬升机制,提出地层充填密实、止浆围护形成、抬升力形成及建筑物结构抬升的四阶段作用模式,并相应总结建筑物稳定抬升的施工技术要点。采用数值模拟方法对厦门市成功大道工程隧道穿越104^#,105^#试验楼注浆抬升进行预测分析,得到建筑物单次抬升量为2.1~3.7mm,且不同抬升力和围护刚度对抬升效果具有显著影响,适当增大抬升力和围护刚度对抬升有利,但其作用有限。工程现场试验结果表明,注浆抬升是反复对地层劈裂一充填一再劈裂的过程,当注浆压力达到0.7~1.0MPa时楼房即开始出现明显抬升,且单次最大抬升量为2.2~3.1mm,这与数值分析预测结果基本吻合。所得结论有助于科学认识城市隧道及地下工程安全性控制的内涵,并可为类似工程提供一定的参考和借鉴。
Based on the analysis ofsettlement recovery characteristics ofbuildings, grouting uplift mechanism is analyzed in detail, consisting of four phases, i.e. ground fill and compaction, construction of exterior isolation curtain structure, formation of uplift force and building structure uplift. The key techniques of steady uplift of buildings are then summarized. The grouting uplift during tunnel construction undercrossing experimental buildings #104 and #105 is predicted by numerical simulation. The results indicate that the maximum uplift is 2.1 - 3.7 ram. It is also shown that uplift force and stiffness of exterior isolation curtain will influence the uplift effect significantly; and proper increments of these two factors are favorable to some degree. For comparison, the field test is introduced, showing a repeated process of soil fracturing, filling and fracturing again. Obvious uplift of the buildings begins when grouting pressure reaches 0.7 - 1.0 MPa, and the single maximum uplift is 2.2 - 3.1 mm, which is nearly close to the simulation result. All conclusions are helpful for improving the scientific understanding of safety control of urban tunnel construction and providing references for similar projects.