Finite Element Computational Analysis Of Deformation On Composite Soil-Nailing Retaining Structure For Excavation

The technology of the excavated retaining is a hot topic in the geotechnical engineering, but its theory research often lagging behind the project practice. This article carries on the two-dimensional model analysis based on ANSYS finite element software to the excavation for composite soil-nailing retaining structure, and confirmed the accuracy and the rationality of ANSYS through a concrete project example to apply to the deformation analysis of composite soil-nailing retaining structure. At present, the excavation retaining structural design way already has developed taking the intensity control as deformation control, In this article deformation rule of the excavation was analyzed mainly, as well as the corresponding the influence analysis of the deformation. The main work includes:1. The ordinary soil-nailing retaining structure the deformation rule was analyzed and summarized. The horizontal displacement and the earth's surface deformation assumes the shape distribution liking" the drum" and "the saddle" separately, the apophysis of the pit bottom sticks out the deformation to the pit bottom above the bulge; The plastic area and the shearing stress distribute in the slope bottom, the protection of the slope bottom should be strengthened in the construction.2. Based on selecting reasonable parameter according to the criterion, The article carries on the influence analysis to ordinary soil-nailing retaining each parameter. It has studied the influence rules of the ordinary soil-nailing retaining structure's maximum deformation separately, and the parameter includes the soil-nailing length, the soil-nailing horizontal spacing, the soil-nailing inclination angle, the soil-nailing diameter, the retaining wall thickness and the top of slope overload, and has produced the reasonable suggestion value of each parameter relatively.3. Selecting a representative composite soil-nailing retaining structure (mixing pile + soil-nailing), which carries on the model analysis. The article summarized the composite soil-nailing retaining structure the deformation rule, And carries on the contrast analysis with the ordinary soil-nailing retaining corresponding deformation, it discovered the control of the composite soil-nailing retaining is stronger than the ordinary soil-nailing; the plastic area and the shearing stress distribution is centralized in the slope bottom place, the protection of the slope bottom should be strengthened in the construction, which can prevent the mixing pile in the slope bottom place to shear. 4. Selecting the reasonable parameter to carry on the influence analysis to the each parameter of the composite soil-nailing retaining separately , the parameters include the pile depth, the pile width, the width and the depth of the pit bottom reinforcement area. It has studied the influence rules of the composite soil-nailing retaining structure's maximum deformation separately, and has produced the reasonable each parameter suggestion value relatively; Through the analysis of each item of soil parameter, it thought the composite soil-nailing retaining displays the more stronger control of the deformation in the soft soil. So the composite soil-nailing retaining is worth promoting.