深基坑变形观测常见问题分析.rar

 深基坑变形观测

    5．1  变形观测的基准点、观测点设定时间不当
    1．现象
基准点、观测点在支护结构和降水井施工未完成前或基坑开挖后设定，不能反映基坑边坡的实际变形情况。
    2．原因分析
    (1)操作者未掌握基坑变形观测知识。
    (2)对沉降和水平位移观测质量不重视。
    (3)基准点、观测点受支护结构、降水井和土方开挖施工的扰动。
    3．防治措施
变形观测所用的基准点、观测点应在支护结构或降水井施工完成后，基坑开挖之前设定，使所观测成果更能切合实际。

5．2  水平位移观测点、沉降观测点和基准点布设位置不当
    1．现象
Deformation Monitoring of Deep Foundation

    5.1 The deformation of the reference points, observation points set the time wrong
    1. Phenomenon
Reference point, observation point in the support structure and precipitation well before the completion of construction or excavation, after setting, can not reflect the actual excavation slope deformation.
    2. Analysis
    (1) the operator does not grasp the foundation deformation of knowledge.
    (2) of the settlement and horizontal displacement observation quality attention.
    (3) reference point, observation point by the support structure, dewatering well, and Earth Excavation disturbance.
    3. Control measures
Deformation of the reference point used, observation points should be in supporting structure or dewatering well construction is completed, set before the excavation so that the observed results more realistic.

5.2 horizontal displacement observation points, observation points and settlement layout is poorly located reference points
    1. Phenomenon