Study On Deformation Monitoring And Warning Of Soft Roadbed In Yue-Chang Expressway

Expressway soft roadbed treatment is a difficult point of engineering,to study the results of settlement changes also is more,but because of the type and thickness of the soft soil,moisture content,such as difference is bigger,many results apply only to particular entity project,results of general guiding significance is not strong.Bid for a specific Yue-Chang expressway soft roadbed of actual situation,this paper has carried out the analysis of the basic geotechnical parameters,the settlement observation and data analysis of typical sections,the analysis of settlement prediction models,and the improvement of the new model's calculation and analysis and accuracy inspection,get the following conclusion:(1)Study on the part of Yue-Chang expressway construction in the soft roadbed,the thickness of crust layer and soft soil thickness difference is bigger,so need to encrypt selected monitoring stations is monitored and analyzed.(2)The stability of soft roadbed depends not only on the subsidence and settlement rate of the vertical direction,but also the horizontal displacement and velocity,and there may even be the danger of slipping into a single slide.By establishing the relationship between the settlement and horizontal displacement of the monitoring stations,the concept of"acceleration" is put forward to better analyze and animated the stability of soft roadbed.(3)After analyzing the shortcomings of the existing Grey GM(1,1)model in the data processing,the modified Grey model is put forward to predict the subsidence of the typical sections.The calculating process of the improved model is less,its expression curve trend more in line with the curve of settlement deformation law of development,and in the application results show that the optimized GM(1,1)model to the compatible ability is stronger.GM(1,1)model fitting accuracy and simulation precision had improved more,calculation process is simplified,can be used as the settlement of soft soil ground prediction model.(4)The optimization model is used to predict the selection of a number of typical monitoring sections,and the analysis and deformation warning are carried out in combination with the measured data and prediction.In this research,set way of settling the acceleration 2 mm/d for the early warning value of degrade construction,when more than the threshold should be launched the emergency response plan in a timely manner,and according to the actual situation of the monitoring cross section,the corresponding treatment measures are put forward and the improved methods,to provide data support for the subsequent construction quality and safety.