【摘要】 【目的】研究将EVP模型应用于预压荷载作用下软土路基水平位移计算的可行性,为软土路基稳定性的评价与控制提供支持。【方法】通过绘制应力和应变增长路径变化的图形,分析了真空预压、堆载预压以及真空-堆载联合预压法加固软土路基时土体的应力和应变变化,介绍了EVP模型的基本公式和计算过程,提出了用该模型表示软黏土的应力-应变关系,结合经典比奥固结理论,推导了考虑蠕变的预压荷载作用下软土固结变形的有限单元计算方法,并进行了工程实例计算。【结果】1)不同预压方法的应力路径和应变路径均不相同;2)用EVP模型描述不同预压荷载作用下软黏土的应力-应变关系时,其具有不考虑应力路径和不划分主、次固结的优越性;3)在比奥固结理论中,用EVP模型反映软土的物理方程时,能全面描述考虑弹黏塑性质的软土路基的固结变形,可准确计算软土路基的水平位移;4)EVP模型的软土土体黏性参数ψ/V和塑性参数λ/V对水平位移都有比较明显的影响。【结论】用EVP模型反映软土的弹黏塑性的本构关系时,可相对准确地计算预压荷载作用下软土路基的水平位移。更多还原

【Abstract】 【Objective】EVP model was applied to calculate horizontal displacement of preloaded soft soil subgrade,which could support the stability evaluation and control of soft soil subgrade.【Method】Stress and strain changes of soft soil foundation reinforced by different preloading methods were analyzed by drawing graphics of stress and strain growth path.Using EVP model to represent the stress-strain relationship of soft soil was then proposed.Combined with classical Biot consolidation theory,the finite element calculation method considering the creep deformation to calculate the horizontal displacement of preloaded soft clayey soil was deduced.Calculation based on practical example was also carried out.【Result】1)Strain and stress paths were different for different preloading methods.2)Neither stress path nor the division ofprimary and secondary consolidations should be considered when applying EVP model to describe the stress-strain relationship of preloaded soft clay soils.3)With the Biot consolidation theory,using EVP model to represent the physical equations of soft soil could comprehensively describe the consolidation deformation with the consideration of elastic-visco-plasticity deformation properties and accurately calculate the horizontal displacement of soft soil foundation.4)Viscosity parameter and plasticity parameter had significant effects on results of EVP model.【Conclusion】Using EVP model to represent the elastic visco-plastic constitutive relationship of soft soil could accurately calculate the horizontal displacement of preloaded soft soil subgrade.更多还原