LANDSLIDE POTENTIAL ANALYSIS ON NEW ROAD OF UNDIP-JANGLI CAMPUS, SEMARANG USING MICROTREMOR METHOD

Abstract

Tembalang is one of the sub-districts in the Tembalang District where landslides or landslides often occur (BPS Kota Semarang, 2021). The New Undip-Jangli Semarang Campus Road is a research area which is one of the areas with a medium level of vulnerability to ground motion (PVMBG, 2022). The study was conducted using the HVSR microtremor method with a total distribution of 40 measurement points. This study aims to identify areas prone to ground movement or landslides based on subsurface characteristics from the distribution of seismic susceptibility index (Kg) values, ground shear strain (GSS) values, identify profiles of subsurface characteristics laterally based on the distribution of shear wave velocity values (Vs). , around Jalan Baru Campus Undip-Jangli Semarang. Based on the research results, the distribution value of the seismic vulnerability index (Kg) around Jalan Baru Campus Undip-Jangli is between 0.27-17.27. The distribution value of Ground Shear Strain (GSS) in the study area is between 2.46x10-4-1,39x10-3. The value of the shear wave velocity distribution (Vs) around Jalan Baru Campus Undip-Jangli Semarang is between 179-2,981 m/s. Earth movement vulnerability analysis based on the parameters above indicates several zones of vulnerability to ground movement, namely at points 3, 4, 5, 6, and 7. Points 9, 10, 13, 14 and 16 and between points 16, 24 and 32. Points 22, 30 and 38 are to the east of the New Undip-Jangli Campus Road. The zone between points 3, 4, 5, 6 and 7 is to the south of the New Undip-Jangli Campus Road. At points 9, 10, 13, 14, and 16 the possible ground motions are rotational avalanches moving south.