Deformation prediction of double-row pile foundation pit based on dynamic neural network NARX time series
In view that the traditional soil mechanics calculation method based on basic assumptions or empirical formulas usually cannot effectively reflect the deformation law of the foundation pit with multi-factor intersection and spatial and temporal characteristics,and then the time series of the monitoring data can truly express the evolution of the deformation of the foundation pit soil body,in this paper,based on the double-row pile foundation pit project of residential distric renovation of dilapidated buidings of Henan Water Plant,which is located in No.72 Tinghong Road,Nanning,Guangxi,considering the influence of two factors,excavation progress and soil exposure time on the monitoring time series,we propose a nonlinear-auto-regressive model with exogenous inputs(NARX)time series dynamic neural network model,which predicts the vertical and horizontal displacements of the key points in key sections in multiple directions.The results show that the trend of the predicted values and the actual monitoring data have good consistency and the residual difference between the predicted one and the practical one is less than 1 mm.Moreover,the residual difference between the horizontal displacement and the predicted value is less than 0.3 mm.The model has good prediction effect,and it also verifies the feasibility of this model applied in the dynamic analysis of the deformation of the double-row pile pit.