深基坑桩锚支护结构锚索轴力监测分析

Analysis on Monitoring of Anchor’s Axial Force of Piles and Anchor Support System in Deep Foundation Pit

摘要:

为了解深基坑桩锚支护结构锚索的工作状态，对石家庄市鸣鹿大厦深基坑桩锚支护结构中预应力锚索轴力进行了锁定及基坑开挖回填过程中的监测。监测成果的分析表明：锚索锁定时穿心千斤顶油压表读数与锚索实际轴力存在较大差别，究其原因是张拉设备与锚具的不匹配；下道锚索张拉锁定会使上道锚索轴力减小，但影响不大；基坑回填后锚索轴力有所下降，但降幅不大；实测最大锚索轴力为锚索设计值的17.9%～50.7%。

关键词:深基坑;桩锚支护;锚索;轴力;监测

Abstract:

In order to understand anchor’s working state of pile and anchor support system in deep foundation pit, the axial force of pre-stressed anchor cable was monitored in the whole process of deep foundation pit excavating and backfilling in Shijiazhuang City. Some conclusions were got by analyzing monitoring results. It was proved that a big difference exists between oil pressure gauge reading of jack and practical axial force of anchor because of the mismatch of stretching equipment and anchorage. Axial force of former anchor was decreased due to latter anchor tension with little effect and axial force of anchor was decreased slightly when deep foundation pit was backfilled. It was monitored that the measured values had 17.9% to 50.7% of designed values.

Key words:深基坑;桩锚支护;锚索;轴力;监测