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Compression behavior of sediments is crucial to geological engineering applications for ascertaining the deformation characteristics of the particular depositional environments. Unfortunately, obtaining the geotechnical parameters required to assess the compression behavior of sediments can be a costly and time-consuming undertaking. This study dev...
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... for the consolidation process Figure 1 is a typical consolidation curve [eÀlog (p 0 )] taken from preliminary data associated with this study. From the initial investigation, it was observed that the best model fitting the preliminary data was an exponential decline model. ...
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... describing the consolidation process, compression change is replaced with volumetric change where, the void ratio, e, exponentially experiences a reduction at a rate proportional to the increase in mean effective stress. Equation (2) is the expression of an exponential model in terms of elog (p 0 ) space (Figure 1): ...
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... A 1 and A 2 represent intercept and initial decline rate of the equation, respectively. The A 1 factor (the intercept) has an explicit physical meaning that indicates the initial void ratio of sediment, e 0 , at the beginning of consolidation processes (Figure 1), and the A 2 factor is a rate-of-void ratio change with respect to the mean effective stress. The A 2 term reflects the volumetric compressibility of the material over the range of stresses. ...
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... consolidation phase of the isotropically consolidated undrained (CIU) triaxial standard method (ASTM D4767 2004) was used to determine consolidation properties of the mixtures. Typical results were shown previously in Figure 1. In general, resultant consolidation curves reflect the capability of volumetric change of the samples in saturated conditions. ...
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... performance of the proposed prediction equation was compared with measured data for verification. Figure 10 shows predicted and measured results of the [eÀ log ðp 0 Þ] relations characterizing the consolidation behavior of the samples. The predicted curves show good agreement with the measured data. ...
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... of the continuous function Figure 11 demonstrates the performance of the presented continuous function (Equation 5) in simulating experimental consolidation data from the literature (Fam and Santhamarian 1997;Chang, Kwon, and Cho 2011;Ahmad 2016;Oh et al. 2017). The figure also shows a comparison between Equation (5) and the prediction methodology presented by Oh et al. 2016), were not addressed in this comparison since they do not explicitly used shear-waves velocities in the eÀ log ðp 0 Þ prediction. ...
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... figure also shows a comparison between Equation (5) and the prediction methodology presented by Oh et al. 2016), were not addressed in this comparison since they do not explicitly used shear-waves velocities in the eÀ log ðp 0 Þ prediction. As seen in Figure 11, the proposed prediction methodology provides a continuous function that does well in capturing both the recompression and virgin compression portions of the consolidation curves. The proposed function also gives a good indication of the effective preconsolidation stress, p 0 c even though the preconsolidation stress is very sensitive to the compressibility. ...
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... this study, analysis of the CIU triaxial tests showed an agreement with these previous studies. Figure 12 shows a negative linear correlation between the normalized undrained shear strength ðS u =p 0 c Þ, and the void ratio, with a strong correlation coefficient (R 2 ¼ 0.875). This relation is given in Equation (10) ...
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... (11) was applied to field data reported by Tong et al. (2018). Figure 13 shows the estimated undrained shear strength profile of the upper part of fine-grained Quaternary sediment in Yangtze Delta deposits. The figure shows the two approaches used to infer undrained shear strength, S u . ...
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... equation used the initial physical properties, initial void ratio, grainsize percentages, and liquid limit that were provided in Tong et al. (2018). Figure 13 also shows an outlier appeared and was accounted for as a possible error might be in the original tested data that caused the overestimation of S u . In general, the results agree well with the general trend of the profile and increasing shear strength with depth. ...
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... this association, the experimental constants a s and b s were found to correlate well with the depositional factors, specifically percent fines, silt percent, and LL. The a s factor and b s exponent are prominent enough to measure capacity Figure 13. Undrained shear strength profile with depth. ...
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The mechanical response of a sediment to an applied stress is significantly affected by variations of material properties, state conditions, and stress states. These stress state and conditions are utilized to infer input parameters for advanced soil constitutive models. Parameters such as void ratio and effective stresses have been readily inferred from shear-wave velocities under low-strain conditions. Thus, this research aimed to develop a shear-wave velocity-based constitutive model within a critical state soil mechanics framework to predict the undrained triaxial behavior of fine-grained sediments. Laboratory tests were performed for sediment samples ranging from silt-predominant to clay-predominant sediments. As result, a new two-term power function was developed that determined mean effective stress as a function of shear-wave velocity. By virtue of this new power function, the Original Cam Clay and Modified Cam Clay critical state models were adapted to estimate the stress-strain behavior and stress paths under undrained conditions, in terms of shear velocity. In addition, correlations were developed using the state and material properties to predict the input model parameters. The developed correlations allow broad application of the proposed framework to different sediment types in which clay and silt are the dominant deposits.
