The Influence of thermal breakage on physio-mechanical behavior of Ghulmet marble north Pakistan

Geotechnical engineering applications comprises high temperature such as deep geological disposal of nuclear waste, exploitation of geothermal process, etc. High temperature and thermal environments can affect the mechanical properties of building materials used in civil engineering (concrete, building rock, steel, etc.). The constant action of regular thermal changes in situations of excess temperature is the main source of the alteration of marble in monumental and artistic buildings. In this study, the effect of both the specimen size and temperature on the physio-mechanical characteristics of dolomitic marble has been investigated. The temperature range selected was 20-600°C. It was observed that the color of samples changes with temperature rise. The Uniaxial compression strength (UCS), P-wave velocity (Vp), and Young’s modulus decreased with temperature rise. While the peak strain increases with temperature. The UCS and the peak strain showed a decreasing trend at the high diameter specimens. In the case of 43mm diameter specimens the peak stress reduced from 60MPa-26MPa with a rise in temperature from 20-600°C. While at the same temperature range the peak strain was observed as 1.7-3.3 and Young’s modulus was 34-8GPa. For 75mm diameter, the peak stress is reduced to 17MPa when the temperature rises to 600°C and Young’s modulus decreased to 4GPa while the peak strain increased from 2.3 to 3.9. The pulse velocity decreased from 2.75 km/s to 0.8km/ and the porosity value increased from 0.9 to 1.5%.