摘要：
In order to evaluate the co-line high-speed railway settlement, and avoid the uncertainty of numerical model parameters as well as the limit of theoretical model, a new method is proposed with the additive stress obtained by numerical model and the settlement obtained by layer-summation theory.In this study, factors which influence the additive stress distribution are analyzed in detail, and the general rule for numerical model establishment is suggested.The soil constitutive model, modulus, Poisson ratio, layered soil and so on can be ignored in the numerical simulation analysis, and the vertical and horizontal model boundary should be 1.5～2.0 times of the railway base width.As the groundwater level influences the additive stress distribution significantly, it is more reasonable to ignore generally the groundwater effect.For engineering verification, a high-speed railway station on Beijing-Shanghai line is chosen, and the additive settlement evaluation is conducted accordingly.The results show that the proposed method is effective practically and theoretically.%为研究复杂工况下的既有高铁沉降评估问题,避免数值模型参数难以确定以及理论分析相对简单的缺陷,采用数值仿真模型确定地基附加应力,应用分层总和法实现对既有并线高铁附加沉降的精准评价.研究中,具体分析影响数值仿真模型附加应力分布的多个因素,并基于数值仿真和Boussinesq理论对比,提出高铁路基数值仿真模型建立的一般准则.数值仿真分析中,可不考虑土体本构、模量、泊松比、层状地基等因素的影响,数值模型水平与深度边界应为1.5倍～2.0倍的路基底宽,地下水对附加应力分布影响较大,提取应力过程中统一不考虑地下水.工程验证中,以并行京沪高铁的某高铁站为分析对象,完成并线高铁的数值仿真分析和附加沉降评估,评估结果证明:应用基于数值仿真模型附加应力提取进行既有高铁附加沉降评估,在理论上和工程实践上均可行有效.
