## 6 Conclusions  
This article presents the first measurements of the shear modulus at small strains of the soft lacustrine sediments of the Ljubljana Marsh. The extensive laboratory program included 45 bender element (BE) and 89 resonant column (RC) tests on cohesive soils with \(PI\) between 11% and 35%. This study not only compared these measurements with widely used empirical relationships, but also investigated the effects of stress anisotropy on soil stiffness at small strains. In addition, the influence of soil sample softness and/or equipment limitations was also investigated in this study. For effective soil modeling, it is important to know the limitations of the equipment used. This knowledge is crucial for determining the necessary parameters for the implementation of the HSS model. These measurements play an important role in the development of the built environment in the Ljubljana Marsh. The main conclusions of this study are summarized below:  
1. \(G_{0}\), measured with BE, is slightly higher than \(G_{max}\), measured with RC. The reason for this is that RC was not able to measure \(G\) at \(\gamma=10^{-6}\), which is also in agreement with [PERSON] et al. (2018). When the measurements were extended according to the modified Hardin-Drnevich model, both \(G_{0}\) (BE) and \(G_{0}\) (model) were within 10% of each other. In addition, the integration of the BE into the RC device facilitates the quality control of the measurements and thus increases the confidence in the measurement results. 2. For the BE test, no significant influence of specimen height on the \(v_{s}\) was found in this study. It was also found that for the RC test, shortening the specimen height to 1.4 times the diameter had no significant effect on the measured \(G_{0}\) and the \(G-\gamma\) curve. 3. Corrections of \(G\) due to \(\Delta u\) for these soft soils are not absolutely necessary. The range of \(\gamma\) in which \(\Delta u\) developed in our experiments is similar to the results of [PERSON] and [PERSON] (2018). 4. It was found that \(\gamma_{0.7}\) was dependent on \(PI\) and \(p^{\prime}\). Trends similar to those of the empirical models were observed, with the exception that \(\gamma_{0.7}\) was lower than the value reported by other authors. However, large differences were also found between the empirical models. Apparently, there is no universally valid empirical model for  
Figure 14: The comparison of increase in \(\gamma_{0.7}\) with \(p^{\prime}\) between the empirical models and the measurements (2018,2018). the prediction of the \(G/G_{0}\) curve, as reported by [PERSON] et al. [19]. It is, therefore, recommended to perform measurements on local soils, especially in cases where the validity of the empirical relationships has not yet been confirmed. * \(G_{0}\) and \(\gamma_{0.7}\) at the same \(p^{\prime}\) were comparable for isotropic and anisotropic stress conditions, indicating that there is no significant influence of the anisotropic stress conditions on the \(G/G_{0}\) curve for this cohesive soil. * It can be seen that both isotropic and anisotropic tests led to an approximately equal \(G/G_{0}\) curve if the test was performed at a stress state close to the field value of \(p^{\prime}\). Testing at significantly higher or lower \(p^{\prime}\) led to different \(\gamma_{0.7}\). To obtain reliable shear modulus values at small strains, the tests should, therefore, be performed close to the field conditions. Conceptualization, T.J., B.P. and M.M. ; methodology T.J., B.P. and M.M. ; investigation T.J.; writing--original draft preparation T.J.; writing--review and editing T.J., B.P. and M.M. ; visualization T.J. and M.M. ; supervision B.P. and M.M. All authors have read and agreed to the published version of the manuscript. This research was funded by the Slovenian Research Agency (research core funding No. P2-0180) within Young Researcher program. Not applicable. Data Availability Statement: Data is contained within the article.