Redesigning the foundation of Bangli solar power plant on a former landfill

Abstract

Bangli solar power plant has 5004 solar modules and uses concrete foundations to support those modules. Due to the location of this power plant was a former landfill, after 5 years in operation, 121 foundations have dropped to lower level. The soil under foundation is not enough to support modules sufficiently. In this paper, a new design has been proposed to correct this problem. The first step is to test the carrying capacity of soil through Sondir boring. Using Standard Penetration Test (SPT) obtained that the layer of hard soil is located at a depth of -10m from the original soil surface with type of soil layer above the elevation of hard soil in the form of silt soil. Using a palm foundation, carrying capacity of a foundation with a width of less than 1.2 meters and a depth of foundation of 1 meter. This makes the average carrying capacity is only 0.39 - 1.20 kg/square cm or the value is too small for foundation of solar power plants. The proposed foundation is a 50 x 50 cm palm foundation that is laid on a geotextile bed. The area of the geotextile depends on the area of decreased foundation.