Calculation Of Earth Pressure And Retaining Structure Based On In-situ Monitoring

For earth pressure and deformation of the pile-anchor retaining structure in the construction process is dynamic, the paper describes the present calculation theory research of retaining structure and earth pressure; to Mu Lianchong-road slope supporting project for the background, analyzes internal forces and deformation of the measured data on the retaining structure in different construction conditions, and based on the method of retaining structure calculating, combining of bending moment and deep displacement monitoring data, back-analyzes the value of the resistance coefficient of earth pressure distribution and earth pressure, achieving monitoring technology in the theoretical analysis application. Specific content and conclusions are as follows:The data analysis of situ-monitoring showed that the internal forces and deformation of the pile was affected by the earth excavation and prestressed anchors. With the increase in excavation depth, the bending moment and horizontal displacement increases gradually to the development of deep at the cantilever stage. Anchor in tension changes the stress state of the pile, and pile displacement under the action of the prestressed anchor cable will have to reverse the deformation, the more recent prestressed anchor cable from the top of the pile,the more obvious deformation control.Combined with the bending moment measured data, and based on the equivalent beam method and1/2sharing method, the paper anti-imposed analyzed the law of the distribution of earth pressure with the soil excavation and prestressed anchors, and obtained the active earth pressure coeffient was smaller and smaller as earth excavation, and the anchor cable tension led to the local increase of earth pressure coefficient. The paper also came to the proportional relationship between soil pressure coefficient under different conditions and the coefficient of earth pressure on the classic method.By a numerical example of considering displacement of earth pressure formula comparative analysis, the paper selected Mei Guoxiong earth pressure formula of considering the displacement, and calculation of earth pressure be as the role of elastic foundation beam load in the supporting structure. Based on the principle of equal effective internal friction angle of the equivalent stress method, equivalent effective stress method, and the total earth pressure equal moment; A numerical example to determine the angle of internal friction in the silty clay layer is equivalent to computing model.According to earth pressure formula of considering displacement, and based on elastic foundation beam method, by constantly adjusting the m value analysis of the value of m impact on pile internal forces and deformation of the law. And combined with the shaft displacement measured data, the paper anti-imposed analyzed m value of the soil in the excavation, and came to m value of soil in accordance with the specification formula cohesive soil was significantly less than the inversion of the value of m. And with the earthworks unloaded, the m value of the soil have varying degrees of attenuation.