基于重标极差分析的基坑监测数据处理

Foundation Pit Monitoring Data Processing Based on Rescaled Range Analysis

基坑工程监测是工程施工过程中的重要保证,其中,对监测数据进行分析是很重要的一环。以某工程基坑监测中的坡顶竖向位移监测数据为例,利用重标极差分析方法,按照时滞的变化,逐步计算时间序列一次差分序列的均值。然后,基于均值计算对于不同时滞的极差和标准差,利用标准差对累计离差的极差进行标准化,得到极差和标准差的比值。如果比值序列随时滞呈现幂率分布的趋势,则幂值就是Hurst指数。最后,根据Hurst指数,判断监测数据序列暗示的系统变化趋势。

Foundation pit monitoring is an important guarantee of the construction, to which the analysis of monitoring data is the key. This paper takes the monitoring data of a top vertical displacement in the monitoring of the foundation pit in a project as an example, using the rescaled range analysis method, and calculates the mean of a time differential sequence according to the time-delay variation step by step. The paper further conducts calculation for different delay ranges and standard deviations based on the mean, and standardize the ranges of the accu- mulated deviation ranges utilizing the standard deviations, obtaining the ratio of range and standard deviation. If the ratio sequence at any time lag shows power-law distribution trend, then the power value is the Hurst index. According to the Hurst index system, the system changing trend can be determined as implied by monitoring data series.