软土地基沉降规律分析及沉降预测方法改进——以成都天府国际机场为例

曲线拟合法(指数曲线、对数曲线和双曲线)因精确度较高、计算方便经常被用来预测地面沉降量,而对于软土地基,双曲线法的预测效果更好。使用双曲线法对成都天府国际机场某试验段监测点数据进行沉降量预测分析并与实测数据对比发现,在监测周期内不同监测时间段和不同软土厚度时,预测误差规律不同。利用监测日期的时间序列和监测点的软土厚度因素对原有的双曲线法进行了改进,并与3种传统曲线拟合法的预测结果对比分析,发现改进双曲线法和指数法的预测精度均很高,但指数曲线法不适合长时间序列沉降预测。研究成果可为成都天府国际机场和其他类似工程地面沉降预测提供参考。

Analysis of soft soil foundation settlement and improvement of its prediction method: case of Tianfu International Airport

The curve fitting methods including logarithmic, exponential and hyperbolic are usually used to predict settlement due to their high accuracy and easy for calculation, among which hyperbolic method has the best effect for predicting soft soil foundation settlement.The monitored data of one experimental section of Chengdu Tianfu International Airport were used to analyze the settlement law by hyperbolic method. Comparing the prediction data and the actual data, it was found that the prediction error varied with different periods in a monitoring cycle and soil thickness. Therefore, the original method was improved by introducing the time series of monitoring date and the thickness of soft soil. Prediction results of the improved hyperbolic method were compared with that of three traditional curve fitting methods. The fitting and prediction accuracy of the improved hyperbolic method and exponential method are very high, but the exponential method is not suitable for the settlement prediction of long series data. The research results can be used as a reference for the prediction of foundation settlement of Chengdu Tianfu International Airport and other similar projects.