Analisis Hubungan Antara Indeks Plastisitas terhadap Kekuatan (Strength) dan Ketahanan (Durability) Pada Batulempung Formasi Kerek, Kabupaten Semarang

Abstract

Trans-Java toll construction was carried out several years ago. One of them is Bawen Semarang toll, which is located in Semarang Regency, Central Java Province. Geologically, Bawen toll crosses Kerek Formation, generally an interbed between mudstone and marl lithologies. Technically, claystone have the character of being easily degraded (slaking), so technically it can become an obstacle during infrastructure development in the future. This research use 8 samples of the Kerek Formation, which will tested for rock physical properties, Atterberg limits, slake durability test, point load index, direct shear, and X-ray diffraction (XRD). The results are the correlation between the plasticity index against the durability and strength of rocks, then the correlation between durability and rock properties, and mineral content. Correlation analysis uses regression method that includes deterministic coefficient data (R2), correlation coefficient (R) and a regression coefficient. Plasticity index, physical property and clay minerals reduce the level of strength and durability. Cohesion, quartz minerals and calcite increase the strength and durability of the Kerek Formation claystone.