深基坑开挖诱发临近建筑物地表开裂的机理研究

为了研究郑州市一处深基坑施工中自身结构稳定，但临近建筑物地表严重开裂的工程问题，对其监测数据的分布特征进行研究，对后续数值计算的精度进行验证，由此得到深基坑开挖过程中土体及围护结构的特殊变形分布规律，为进一步研究其破坏机理，以放大效应对模型进行处理。结果表明，由于护坡桩水平变形，引发基坑土体变形，经锚索加固的土体，随着距基坑距离增加而变形，但在锚索锚固端附近变形却急剧增大，远远大于周围土体变形；水平方向变形不均匀进而引发竖直方向不均匀沉降，在土体及上部建筑自重作用下，竖向不均匀沉降继续发展，当不均匀沉降过大，必然出现拉张裂缝。

Deformation Mechanism of Ground Cracking of Adjacent Buildings Induced by Deep Foundation Pit Excavation

In order to analyze the structure stability of a deep foundation pit construction in Zhengzhou and the engineering problems such as adjacent building surface cracks,the monitoring data was adopted to develop a model of the distribution characteristics,which is then verified by numerical calculation,the resulting soil in the process of deep foundation pit excavation and retaining structures of special distribution regularity of deformation.The failure mechanism is further discussed to test the amplification effect of the model.The results show that the horizontal deformation of soils behind the pile is caused by piles,which reduces with the length of founding pit,but it greatly increases near the anchorage end of the anchor cables,because the soils are much strengthened by the cables,while the other soils still keep the same mechanical properties.If the cables were not so long enough that the horizontal deformation would be very much.So the vertical differential settlement will occur.