Abstract: The “fixed position”, the “high efficiency” and the “reduced error” are used as the research objectives of this paper. A new displacement monitoring method in the foundation inspection is proposed. By using the repeated observation method, the improved monitoring device can reduce the system error, improve the precision of the monitoring displacement data and improve the monitoring efficiency. Combined with the actual data analysis and the displacement of the beam adjustment method and double system vibration displacement method, can be relatively accurate correction based on top of the vertical displacement, is given priority to with the first set of monitoring system in the process of data collection. A second system is complementary, monitoring at the same time, mutual correction, improve the test accuracy, reduce the influence of the error of the results. The improved monitoring device can accurately and quickly monitored the variation characteristics of the settlement and the fluctuation of the soil surrounding the pile, evaluate and analyze the influence range of the soil changes surrounding the pile on the benchmark pile, and provide a reasonable erection distance for the benchmark beam.

Key words: Monitoring Device, Displacement Correction, Dual System Monitoring, Settlement of Soil Surrounding Pile