The Comparison Between 2-D and 3-D Slope Stability Analysis Based on Reinforcement Requirements

Abstract

The landslides in the field often do not have an infinite length, making 3-dimensional assumptions more appropriate for the design. Meanwhile, they are mostly analyzed in design by assuming the landslides occur infinitely with plane strain in a 2dimensional approach. This assumption becomes less precise due to the consideration of the safety factor based on 2-dimensional conditions while the landslide happens 3-dimensional, and this has further effects on the need for reinforcement. This research was conducted to determine the level of influence 2-dimensional and 3-dimensional landslide safety factors have on the number of reinforcements required. A limit equilibrium method was used in the study. The number of geotextile reinforcement needs with a 3dimensional sliding model is calculated based on existing research results. The results are then compared with the amount of geotextile reinforcement required with a 2-dimensional sliding model. The results showed the possibility of having the same amount of reinforcement under 2-D and 3-D assumptions in the homogeneous soil, while different results were found with heterogeneous soil layers due to the variations in soil conditions. Comparison of the number of geotextile reinforcement requirements between 2 dimensions and three dimensions still needs to be further developed by using more varied soil data. This is done considering that existing studies are only limited to soil, which tends to be homogeneous.

Causes of Landslides in Road Embankment with Retaining Wall and Pile Foundation: A Case Study of National Road Project in Porong-Sidoarjo, Indonesia

“…At the same time, the calculations were made based on a twodimensional (2D) sliding assumption. The 2D slide generates a lower SF than 3D, which requires lesser piles [26], [27]. This means the number of pile foundations for the retaining wall barely matched the requirements for the overall stability of a 10 m pile.…”

Comparison of Embankment Reinforcement Requirements with Geotextile on Soft Soil with 2D and 3D Slope Stability Analysis Methods

“…The researchers developed the basic theory of 2D slope into the 3D slope. Most of the results of previous studies stated that the 3D and 2D factor of safety ratio was more than one (SF 3D > SF 2D) for cohesive soils and less than one (SF 3D < SF 2D) for non-cohesive soils (Sari et al, 2020). Research conducted by Chen and Chameau (1982) stated that the ratio of the 3D and 2D safety factors was between 0.98 -1.5.…”

Comparison of safety factor and geosyntetic reinforcement requirement for slope stability using 2-D and 3-D analysis method

“…Most of the previous results further showed that the values of safety obtained from the 3-D and 2-D methods were different, due to the soil types, landslide area assumptions, and slope dimensions being analyzed. These differences are found to affect the treatment of the embankment when designing the reinforcement requirements [35], [36]. Therefore, this study aims to analyze the effect of the SF differences in conducting the design of reinforcement requirements.…”

“…The ratio of 3-D and 2-D safety numbers in several previous studies is to be used in obtaining different reinforcement requirements. The study is also a continuation of the research conducted by [35]. Based on the background descriptions above, this study aims to obtain a comparison between the 2-D and 3-D slope stability methods.…”