Many natural slopes were subjected to change in geometry in order to make room for construction of infrastructures. This paper presents stability analysis of a natural slope subjected to cutting to make room for the development of factories in an industrial site. The analysis was performed for the most critical slope section and analysis was made in comparison to the case presented in literature. Data required for slope stability analysis were retrieved from relevant project report. The result shows that the stability\ud of the slope decreases due to slope excavation and stabilization should be done in order to limit further reduction of shear strength due to yielding of soil mass. Analysis using circular failure surface such as Simplified Bishop is simple and is usually suitable for analysis of existing slope where there is no indication of incipient failure. However, pre-defined failure surface in\ud Morgensten Price method is more useful if failure surface could be predicted based on slope assessment or when rectification work has been applied

Seventeen percentages of Sumatra is covered with peat deposits. Some 1.6 million Ha is deposited in the East coast of South Sumatra. More over, 63.503 Ha is found in Ogan Ilir Regency. Laboratory soil tests are performed to determine the engineering properties of the peat. Generally the tests use undisturbed samples obtained with a block sampling from sites in Ogan Ilir Regency, but the physical tests for specific gravity, water content, and ignition loss occasionally employ disturbed samples. The tests for the determination of the engineering characteristics involve shear strength, consolidation, and permeability tests. The test results show that the peat soil in Ogan Ilir can be classified as fibrous peat with degree of decomposition (H4–H5 in von Post scale) and fiber content > 20 %. The average natural moisture content of the peat is 441,933 %. The average results of direct shear test showed the effective cohesion (c’) and the effective angle of internal friction (’) are 7.62 kPa and 19.930. The average coefficient of rate of consolidation (cv) obtained from Oedometer test ranged from 3.20 from 0.93 for pressure range of 25 to 400 kPa. In general, the results show similar values with the reference data of other peat soils.

Finite element analysis of composite beam-to-column connection with cold-formed steel section AIP Conference Proceedings 1903, 020024 (2017)

Expansive clay has a high potential to swell if compared to other types of clay. Expansive clay also has very low bearing capacity so that a method of soil improvement was needed to improve the soil. This type of soil can be found in Gasing village, Tanjung Api-Api Km. 11 Banyuasin regency of South Sumatra Province. This research aims to study the mixture of gypsum plafond waste as additives in the process of stabilizing expansive soil clay. It can be made according to the needs of the mixture. In this study, the percentage of mixture of gypsum plafond waste are 5 %, 10 % and 15%. The test used an Oedometer (SNI 2812: 2011/ASTM D2435) equipment. By giving the pressure of 2.5 kN/m 2 ; 5 kN/m 2 ; 10 kN/m 2 ; 20 kN/m 2 ; and 40 kN/m 2. The test results of the clay without mixture with gypsum plafond obtained were liquid limit value (LL) = 67%, plastic limit (PL) = 26.38% and plastic index value (PI) of 40.62%. Spesific Gravity (Gs) = 2.696, optimal water content (opt) = 21.55 % and optimal dry weight (opt) = 1.55 gr/cm 3. Therefore, the soil sample was an expansive clay type and classified as A-7-6 (AASHTO classification). Consolidated test results show that soil compression index (Cc) = 0.190. After mixed with gypsum plafond waste of 15 %, the compression index value (cc) = 0.080. This indicates that the compression index value (cc) has decreased. Based on the above, it can be concluded that the mixture of gypsum waste in expansive clay causes soil settlement.

The design of a foundation is inseparable from the type and strength of the soil, for example, clay soils have poor properties for structures due to their low bearing capacity. Therefore, it is necessary to modify the model of a foundation to increase its bearing capacity and one of the popular methods is the application of folded plate on a flat foundation with angles and flange lengths on both sides. Therefore, this research presented its application at different flange lengths of 0.5B, 0.75B, 1B, 1.25B, and 1.5B where B is the width of the flat plate and the results showed the bearing capacity of the folded plate was higher than the flat foundation. Moreover, an increment in the folded length led to a bigger ultimate load and smaller settlement but the ultimate load and settlement were observed to be almost constant at over 1B. This means the optimum variation where the flange length is equal to the foundation width is 1B and it was observed to have increased by 129.52 % using the Tangent Method and 148.4 7% with Butler Hoy Method. Meanwhile, the lowest settlement factor for the folded plate foundation was 0.22 with the highest bearing capacity of 61.19 kN/m2