Abstract The input parameters for the hardening law for the elasto-plastic constitutive model of unsaturated soils are generally fitting parameters that control the degree of hardening response and cannot easily be determined without the results of experimental tests in which the changes in suction, water content, and volume are measured or controlled. However, it is next to impossible to complete such precise experimental tests on all the geomaterials comprising the earth structure to be analysed, such as an embankment. It is important, therefore, to establish a method for determining these parameters from more easily attainable data on the material. This paper presents a practical method for estimating the input parameters related to hardening/softening due to desaturation/saturation in the elasto-plastic constitutive model proposed by Ohno et al. (2007a) from a compaction curve, which is frequently obtained and widely used in engineering practice. In the proposed method, the input parameters are estimated by simultaneously solving three theoretical equations, each of which holds for a different point, indicating the statically compacted state on the dry side of the compaction curve, while the approximately represented compaction curve is used instead of a hand-drawn one. The paper demonstrates that the proposed method enables the estimation of the input parameter values within a range small enough so as not to affect the results of the simulation, irrespective of the way in which the points on the represented compaction curve are selected. The validity of the estimated parameters is verified and then discussed through a series of static compaction test simulations.

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从压实曲线估算非饱和土弹塑性本构模型参数的实用方法

摘要 非饱和土弹塑性本构模型硬化规律的输入参数一般是控制硬化反应程度的拟合参数，如果没有实验测试的结果，吸力、含水量、和体积被测量或控制。然而，几乎不可能对构成待分析的地球结构的所有地质材料（例如堤防）完成如此精确的实验测试。因此，重要的是要建立一种从更容易获得的材料数据中确定这些参数的方法。本文提出了一种实用的方法，用于估计与 Ohno 等人提出的弹塑性本构模型中由于去饱和/饱和引起的硬化/软化相关的输入参数。(2007a) 来自压实曲线，该曲线在工程实践中经常获得并广泛使用。在所提出的方法中，通过同时求解三个理论方程来估计输入参数，每个方程都适用于不同的点，表明压实曲线干侧的静态压实状态，而使用近似表示的压实曲线代替一张手绘的。论文证明，所提出的方法能够在足够小的范围内估计输入参数值，以免影响模拟结果，无论选择表示的压实曲线上的点的方式如何。验证了估计参数的有效性，然后通过一系列静压试验模拟进行了讨论。