针对深厚土层内部沉降监测方面存在的测点少、量程小、误差大和自动化程度低等不足,研制了一种深厚土层内部沉降监测新装置。该新装置由锚固单元、测量单元和数据采集单元等3部分组成,通过钻孔分节段安装至监测土层内,在监测层的上下界面处设置液压与弹簧组合驱动式新型锚固头,上下锚固头之间串接位移计和位移传递杆,最下端锚固头位于稳定地层内,通过分层测量、逐层累加的方法,得到各监测层的压缩量和地基的沉降量,实现对地层内同一垂直线方向的多测点、大量程、高精度和自动化监测,为深厚土层的内部沉降监测提供了新方法。新装置的性能测试和实际应用结果表明:新装置与周围土体的变形协调性好,测量精度较高,数据稳定性和连续性均较好,适用于地下水位以上、细颗粒土层的分层沉降监测。
A new device for monitoring sub-surface settlement in deep soil layers has been developed to address the shortcomings of limited measurement points, small measurement ranges, large errors, and low automation. The new device consists of anchoring unit, measuring unit and data acquisition unit. It is installed in sections into the monitoring soil layer through drilling. A new type of anchoring head driven by hydraulic pressure and spring is set at the upper and lower interfaces of the monitoring layer. A displacement meter and displacement transmission rod are connected in series between the upper and lower anchoring heads, and the lowest anchoring head is located in the stable stratum. Through layered measurement and layer-by-layer accumulation, the compression of each monitoring layer and the settlement of subsoil can be obtained, so as to realize multi-point, large-scale, high-precision and automatic monitoring of the same vertical direction in the stratum, which provides a new method for sub-surface settlement monitoring of deep soil layers. The performance testing and practical application results show that the new device has good coordination with the surrounding soil deformation, with high measuring precision, good data stability and continuity. It is suitable for layered settlement monitoring of fine-grained soil layers above groundwater level.
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