Identification of characteristics soil affected and not affected liquefaction at the north part of Petobo Village

Abstract

On September 28th, 2018, an earthquake measuring 7.4 Mw shook Palu and its surroundings. The effects of this earthquake caused natural disasters, namely liquefaction. One of the areas of Palu City that was affected by liquefaction is located in Petobo Village. With Petobo's position in a relatively sloping area, this situation triggers landslides or landslides along with the liquefaction effect. This study aims to determine the characteristics and bearing capacity of the soil in the affected area and not affected by liquefaction, especially in the central part of the north avalanche. This study consisted of 2 test methods: field testing carried out with the Swedish Weight Sounding at 4 points in the affected area and 2 points in the area unaffected by liquefaction and laboratory testing including sieve analysis, Atterberg limits, direct shear and bulk density. The results of the field research show 3 parameters, namely Nsw, qa and qu. The value of Nsw in the affected area is in the range of 0 n/m-208.33 n/m, the value of qa is in the range of 30 kN/m2-196.67 kN/m2 and the value of qu is in the range of 45 kN/m2-201.25 kN/m2 while the area is not affected, the value of Nsw is in the range of 0 n/m-250 n/m, the value of qa is in the range of 30 kN/m2- 230 kN/m2 and the value of qu is in the range of 45 kN/m2-232.50 kN/m2. Soil classification results from laboratory tests on affected soils are SC (Clayey Sand) and unaffected soil, namely SC (Clayey Sand) and SM (Silty Sand). Based on the SWS parameter, the bearing capacity of the soil in the affected area is 32, 12 t/m2, and the non-affected area is 113, 70 t/m2. Based on the direct shear parameters, the soil bearing capacity in the affected area is 30, 54 t/m2 and the non-affected area is 136, 72 t/m2.