Influencing Factors Sensitivity Analysis Of High-Speed Railway Embankment Stability And Foundation Settlement

The embankment stability and settlement need to be control strictly in the design of embankment for high speed railway. At the same time the embankment part of settlement after excessive in operating high-speed railway make a reinforcement to control the settlement further develop is also very necessary. Influencing factors analysis based on the high-speed railway embankment stability and settlement are carried out to establish its controlling factors in order to parameter optimization and optimize the existing programs of local foundation reinforcement for disease treatment of high-speed railway foundation settlement overrun have an important project significance.With orthogonal design theory, the sensitivity factors of the embankment stability were analyzed by limit equilibrium analysis software Slope/W and Study the key influencing factors of foundation settlement using ABAQUS finite element software, moreover, explores the relationship between the foundation plastic deformation and embankment stability, in addition, optimization study at the toe of the embankment foundation reinforcement by drilling program is carried out in regard to the existing high-speed rail subgrade occurs a larger plastic deformation. The main work is as follows:(1)Towards to two kinds of stability control conditions about embankment slope and foundation, establish stability analysis model of embankment slope and stability analysis model of embankment foundation based on the limit equilibrium analysis, and research primary and secondary order of each factor to the corresponding calculation model by orthogonal design, moreover, have a depth analysis to the interaction among influencing factors on uniform slope conditions. The main influencing factor of embankment slope stability under good foundation conditions is the internal friction angle of embankment filler, and there is a significant interaction between slope ratio and internal friction angle, so as slope height and cohesion, besides the improper value of each factor will affect the sort by sensitivity, moreover the stability of embankment is mainly controlled by foundation state under weak foundation and surface tilted conditions, furthermore the foundation soil strength and ground surface slope are the main factors of slope stability.(2)Using the ABAQUS finite element software establish an finite element model for integrated of embankment and foundation, respectively analyze the primary and secondary order of embankment settlement and foundation settlement influencing factors using orthogonal design under good foundation conditions. The analysis of embankment settlement influencing factors show that the main influencing factors are embankment filler modulus and embankment height. Foundation settlement are calculated by linear elastic model and Mohr-Coulomb elastic-plastic model, The results of key influencing factors by foundation settlement influencing factors sensitivity analysis based on different calculated models are consistent and the key influencing factors are foundation soil modulus and embankment height.(3)The plastic deformation of the foundation were analyzed by Mohr-Coulomb ideal elastic-plastic model based on the low-intensity foundation conditions and the results show that the embankment stability is reduced with the foundation strength decreases and the increasing trend of foundation plastic deformation is significantly. The correspondence between the foundation plastic deformation y and embankment stability safety factor x under different embankment height conditions are fitted by negative power functions y=axh, Embankment height of12m,16m,20m corresponds to the a values are followed by0.1169,0.1768,0.2951, b values are-6.875,-7.008,-7.052. The influencing factors sensitivity of foundation settlement and foundation plastic deformation are discussed by orthogonal design under the soft foundation conditions. The results show that the main influencing factors of foundation settlement are embankment height and foundation soil modulus and the influencing factors primary and secondary order of foundation plastic deformation are embankment height, internal friction angle of foundation, foundation modulus, cohesion foundation, while the range of the four factors have no significant difference and the four factors all have a greater impact on the foundation plastic deformation.(4)Towards to the disease treatment of high-speed railway foundation settlement overrun launch a optimization analysis of foundation reinforcement program at the toe of the embankment and have a finite element analysis based on optimized reinforcement scheme of locally foundation. The results show that the proposed four reinforcement scheme can effectively limit the plastic deformation of foundation and the reinforcement effect is obvious. And have a comprehensive analysis of the influence on the reinforcement effect while the reinforcement area and reinforcement area modulus change by orthogonal design. The results show that the reinforcement area inside the border impact greatest and oblique grouting reinforcement make the reinforcement area so close to the centerline of foundation have the best reinforcement effect.