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Copyright of Irrigation & Drainage is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Irrigation & Drainage is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Utilization of rubber-sand mixtures as construction materials, such as lightweight filling materials, embankment construction, seismic isolation materials, ... etc., provides significant advantages, as scrap tires induce environmental issues. In this study, unconsolidated undrained triaxial tests were performed to examine the shear-strength characteristics of geogrid-reinforced sand-rubber mixtures. The rubber percent (10%, 20%, 30%, 40%, 50% and 60%), the confining pressure of the cell (19.6 kPa, 49 kPa and 98 kPa) and the number of geogrid reinforcements (1 to 4) were varied for investigating the impact of these parameters. The relative density of sand remained constant (80%) during the test. The test results were evaluated in terms of the stress-strain characteristics of rubber-sand mixtures. The test findings demonstrated that by increasing the confining pressure of the cell, the same rubber-sand mixtures with the same relative density and rubber content take more loads. The peak stress of unreinforced rubber-sand mixtures increased with the increasing proportion of rubber content up to 30%, beyond which it decreased as rubber content increased. Maximum peak stress and axial strain have been achieved with 50% of the rubber content and four layers of geogrid reinforcement. The brittleness index of the rubber-sand mixture reduces when geogrid reinforcement is added. The minimum brittleness was found to be 0.042 at 50% rubber content with three layers of geogrid reinforcement. [ABSTRACT FROM AUTHOR]

Rainfall has become a main trigger of slope failure for embankments in most coastal areas. The common slope stability analysis is incapable of accurately forecasting slides where suction pressures play a critical role. This realization is used for elaborate stability analyses, which include mesh and suction to better predict rainfall-induced slides at effective slopes. Jute fibre is one of the reinforced materials which is utilized to improve soil strength. Accordingly, the present study explores to study the effects of slope inclination on soil stability and the collected soil samples using jute fibre in artificial rainfalls. Therefore, this article presented various assessments for soil sample testing. Different tests like sieve analysis, permeability test, direct shear test (DST), liquid limit, plasticity limit, and numerical modelling were conducted in the laboratory. Geo-studio 2021 is the software utilized for numerical and experimental modelling. The findings of the research revealed that the failure is caused by a soil suction loss when the inclination of the slope is higher than the soil friction angle. Subsequently, when the inclination of the slope is lower than the soil's friction angle, the collapse is caused at the slope's toe due to the improvement of the positive water pressure. Furthermore, when the slope angle increases, slopes are becoming increasingly vulnerable to rapid collapse under rainfall. Consequently, the article studies the jute fibre which is combined with soil to improve its soil performance while using two rows, three rows, and four rows of jute. This estimation results that the jute fibre performs better than the without using jute fibre under different rainfall conditions. According to the findings, the random distribution of jute fibres had a favourable influence on both strength measurements and safety aspects. Utilizing the factor of safety and matric suction, the performance of jute fibre is superior to those without using jute fibres. Consequently, the proposed work improves the stabilization of soil, and factor of safety with jute fibre in rainfall conditions. [ABSTRACT FROM AUTHOR]

Many geotechnical sites are unsuitable for construction due to their low bearing capacity. In the present study, stone column technique has been analyzed for the ground improvement of soft clayey soil. The change in bearing capacity of stone columns with variation in static parameters has been estimated using Indian Standard Code 15284 (IS Code) - 2003, Bouassida's method (1994), and Afshar's and Ghazavi's method (2014). From the analytical solution of the expression by the IS Code method for bearing capacity of the stone column, it is found that with the increase in diameter of the column, the bearing capacity of the stone column increases. Comparison of the results from the three methods has been conducted and it was found that values obtained from IS Code are very close to those obtained by the other two analytical methods. Also, the critical interpretation of the results shows that the IS Code gives safer design values for a wide range of the static parameters. The results of the IS Code were compared with the experimental findings to evaluate the ability of the method to design the actual load carrying capacity of the stone column. [ABSTRACT FROM AUTHOR]

Stone columns are usually provided in groups to support various geotechnical structures, such as embankments, storage tanks, etc. Several experimental and numerical studies have been performed to study the response of stone columns as soil reinforcement. For relatively moderate loading of a structure, application of stone columns either singly or in groups is widely used. The enhancement of strength of the soil is governed by the type of original subsoil and the properties of the coarse aggregate materials used for the stone columns. Several researchers have analyzed different coarse-grained materials using various plane strain approaches to model the stone columns. This article deals with the non-linear analysis of an isolated stone column embedded in a semi-infinite medium of sandy soil. The parameters which crucially affect the settlement characteristics and the bulging failure of stone columns have been determined. The suitabilities of two different natural aggregates, pebble gravels, and crushed pebble gravels as materials for the stone column have been compared on the basis of their settlement behavior using 2D numerical modeling with the PLAXIS software. [ABSTRACT FROM AUTHOR]

Soil uncertainties play an important part in the analysis and design of geotechnical structures. The effect of uncertainties on the geotechnical structures and their influence on the probability of failure or reliability of the structure is of great interest for geotechnical researchers. Probabilistic-based slope stability analysis incorporates the uncertainties present in the soil, as expressed in terms of mean, variance, and autocorrelation. In this paper, reliability analysis of a finite cohesive soil slope based on the probabilistic approach is presented using the First Order Second Moment (FOSM) method, First Order Reliability Method (FORM), and Monte Carlo Simulation (MCS) method. Stability analysis has been performed using the ordinary method of slices to calculate the Factor Of Safety (FOS) of the slope under undrained conditions. The reliability analysis has been implemented in the MS-excel spreadsheet environment and was mainly focused on the two models, namely the deterministic model for calculating the FOS of the slope and the uncertainty model for generating the random variables of uncertain soil parameters. The reliability index (β) of the soil slope and its corresponding probability of failure (Pf) was calculated using the above methods. The obtained result shows that the MCS method has significantly shown better performance than FOSM and FORM because of its robustness and simple approach to calculate Pf and β of the slope. [ABSTRACT FROM AUTHOR]

Soil slope stability is an important concern for constructing any structure on a soil slope. As soil is heterogeneous in nature due to its formation process, soil slope stability analysis cannot be done without considering the variability in the properties of soil. To consider the variability in soil properties, the research approach has shifted towards a probabilistic approach. In this paper, two soft computing techniques i.e., Adaptive Network based Fuzzy Inference System (ANFIS) and Multivariate Adaptive Regression Spline (MARS), are used for reliability analysis of layered soil slope stability. As the soil slope stability mainly depends on three properties of soil i.e., unit weight (?), cohesion (c) and angle of shear resistance (?), these are taken as input variables for the models and factor of safety of slope was taken as output. The stability analysis is carried out using the Morgenstern-Price method. The models were accessed using statistical parameters like NS, RPD, RMSE, R2, PI, GPI. The results showed that although both models performed well, the model MARS outperformed the other. Therefore, MARS can be used as a reliable soft computing technique for analyzing soil slope stability. [ABSTRACT FROM AUTHOR]

Soil uncertainty plays a crucial role in the analysis and design of any geotechnical structure. Reliability based probabilistic method of analysis is particularly suitable to address the situation arising due to soil uncertainties. This paper presents a reliability based probabilistic method of analysis of a finite slope by considering the uncertainty in the cohesion and angle of internal friction of the soil. The reliability index (β) and its corresponding probability of failure (Pf) of the slope are determined using different methods namely Monte-Carlo simulation (MCS) method, First order second moment (FOSM) method and Subset simulation (SS) method. The reliability based probabilistic slope stability analysis has been developed and carried out in a MS-Excel spreadsheet. This spreadsheet mainly analyzes three different models i.e. deterministic model for calculating the factor of safety of the slope, uncertainty model for generating random samples of uncertain parameter of the soil and uncertainty propagation using subset simulation. The stability analysis is carried out using the ordinary method of slices. It is found that the SS method has shown better performance in terms of efficiency and accuracy as compared to the MCS method and FOSM method. Moreover, the study also demonstrate that the SS method can help in understanding the problem and can better assess the risk involved. [ABSTRACT FROM AUTHOR]