UH模型在双层地基受力变形分析中的应用

基于姚仰平等提出的 UH 模型，将土层的初始超固结比 OCR 引入到 UH 模型的有限元程序中，通过设置不同土层的 OCR 来控制土层的软硬程度，采用 UH 模型的有限元程序对上硬下软双层地基进行了有限元分析。首先将 UH 模型与简化双层地基应力系数法、 Boussinesq 弹性理论计算的附加应力进行了比较，从而证明 UH 模型在分析上硬下软双层地基应力特性方面的优越性，它能够反映上硬下软地基的应力扩散现象；然后用 UH 模型有限元程序计算了土层为不同 OCR 的上硬下软双层地基的附加应力，研究了土层 OCR 对双层地基应力状态的影响；最后对上硬下软双层地基的固结沉降进行了有限元分析，研究了地基沉降、土体应力应变特性和孔压变化规律。

Application of UH model to analysis of deformation of double-layer subgrade

Based on the UH model proposed by Yao et al,the initial over-consolidation ratio(OCR) is introduced to the finite element program of UH model.By setting different OCRs for different soil layers,the soft and hard degrees of soils are controlled.The finite element analysis of strong-over-soft double-layer subgrade is performed by using the finite element program of UH model.Firstly,the additional stress calculated by using the UH model,the simplified double-layer subgrade stress coefficient method and the Boussinesq elastic theory are compared.The comparisons indicate that the UH model has superiority in the analysis of the stress characteristics of double-layer subgrade,and it can reflect the stress diffusion phenomenon of strong-over-soft double-layer subgrade.Then the additional stress of strong-over-soft double-layer subgrade with different OCRs is calculated by the finite element program of UH model,and the effect of OCR on the stress state of double-layer subgrade is studied.Finally,the finite element analysis of the consolidation settlement in the strong-over-soft double-layer subgrade is performed.The subgrade settlement,stress-strain behavior and change of pore pressure in double-layer subgrade are studied.