PHYSICAL AND NUMERICAL MODEL STUDY ON COMPRESSIVE STRENGTH TESTS OF LIMESTONE AT TEMPERATURE VARIATIONS 25 °C TO 400 °C

• Main Author: Hasan, Uswath
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/80440
• Institution: Institut Teknologi Bandung

The increase in temperature during Underground Coal Gasification (UCG) activities can affect the interburden of the coal that has been left behind after the gasification process, so that the voids created after Underground Coal Gasification (UCG) activities can cause the interburden which previously had the strength to withstand the load above it to experience subsidence. This is caused by the weakening of the interburden due to exposure to high temperatures, so it is necessary to test the physical and mechanical properties of the coal interburden and the layers above it. This study used limestone rock as the sample and then tested it by testing its physical and mechanical properties (compressive strength, elastic limit, Young's modulus, poison ratio, ultrasonik velocity and point load index) against the temperature variations. Comparison of test results at room temperature (25 ? C) with tests at 400 ? C showed that density (?) decreased by 0,35%, porosity (n) increased by 193,38%, void ratio (e) increased by 195,54%, Compressive Strength (?c) decreased by 30.36%, Young's Modulus (E) decreased by 9.97%, Poisson's Ratio (????) 8.62%, numerical modeling of uniaxial compressive strength tests with the influence of temperature variations was carried out for detailed reverse analysis of Young's Modulus in limestone rocks caused by temperature variations experienced by the rock when subjected to pressure. To find out changes of the type of composition and minerals as well as cracks from rocks that had experienced varying temperatures, XRD, XRF and SEM tests were carried out to detect them.