Slope stability analysis is very important in slope design so it can manage and maintain the infrastructure assets. If the slope is unstable, it can damage the infrastructure around the slope. The method commonly used in slope stability analysis is 2D modeling which assumes the length of the landslide area is not limited or continuous. Landslides that occur in the field are limited and not continuous, so 3D modeling is more suitable than 2D modeling. 3D slope stability analysis has been developed by various researchers. Most of the results of previous studies stated that the 3D and 2D factor of safety ratio were more than one for cohesive soils and less than one for non-cohesive soils. This safety factor affects the amount of reinforcement needed. Differences in 2D and 3D safety factors will cause differences in the amount of reinforcement needed. Therefore, this study was conducted to determine the differences in the 2D and 3D slope stability analysis result. Slope stability analysis was carried out using LEM, where the 2D slope stability used the Fellenius method while the 3D slope stability used the Hovland method. Calculate the required reinforcement amount using geotextiles with Tilt = 250 kN/m. The results obtained from this study are the 2D safety factor is smaller than the 3D safety factor. The 3D and 2D safety factor ratios range from 1.09 -1.397. While the amount of reinforcement required in the 3D analysis is less than in the 2D analysis with the ratio of 3D and 2D reinforcement requirements ranging from 0.5 to 0.955 depending on the width and height of the embankment.

Settlement of embankments on soft soils is a significant problem in geotechnical engineering to maintain pavements, buildings, and other facilities on them. The problem that often arises is not being able to predict the magnitude of consolidation compression accurately, this occurs due to uncertainty in field conditions, laboratory testing, and data interpretation, as well as assumptions made in the development of 1-D consolidation theory. Based on the causes of inaccurate settlements predictions, it is necessary to carry out research on a better method for predicting embankment's settlement on soft soil. To obtain the correct method, a study was conducted by comparing and examining the consolidation settlement of embankments built on soft soil using theoretical calculations and field measurement results. The process involved monitoring the settlements using 25 plate measurement data in embankment preloading for housing and building construction over the very soft clay. The results showed the compression parameter, especially Cc, is very influential on the compression ratio, and the Cc value based on the empirical formula of Bowles (1989) turned out to be the most suitable for the actual compression results in the field with a compression ratio between 0.6-1.1 and confidence of level 90%.

None of numerous previous methods for predicting pile capacity is known how accurate any of them are when compared with the actual ultimate capacity of piles tested to failure. The author's of the present paper have conducted such an analysis, based on 130 data sets of field loading tests. Out of these 130 data sets, only 44 could be analysed, of which 15 were conducted until the piles actually reached failure. The pile prediction methods used were: Brinch Hansen's method (1963), Chin's method (1970), Decourt's Extrapolation Method (1999), Mazurkiewicz's method (1972), Van der Veen's method (1953), and the Quadratic Hyperbolic Method proposed by Lastiasih, et al. (2012). It was obtained that all the above methods were sufficiently reliable when applied to data from pile loading tests that loaded to reach failure. However, when applied to data from pile loading tests that loaded without reaching failure, the methods that yielded lower values for correction factor N are more recommended. Finally, the empirical method of Reese and O'Neill (1988) was found to be reliable enough to be used to estimate the Q ult of a pile foundation based on soil data only.

Civil Engineers in designing the ultimate brearing capacity of the pile usually uses several empirical methods. Then usually the loading pile test will be conducted to confirm the ultimate carrying capcity in the field. Based on conditions that often occurs in the field, an empirical method of research is carried out to find out which method is closest to results of the field test. So that in designing the ultimate bearing capacity of the deep foundation will be closer to the field conditions. The empirical methods used in this case are the method of Bazara and Luciano Decourt, while the interpretation pf filed results uses the methods of Chin, Mazurkiewiz and Lastiasih. Based on the results of empirical methods and interpretation of the ultimate bearing capacity of the field test, the results of the pile loading test will be analysed using finite element. The result of this research shows Finite Elemet method, Luciono Decourt and Lastiasih are the closest produce produce ultimate bearing capacity with loading pile test until failure.

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