Geomechanical properties of volcanic rocks from Deccan Traps
Endalu Tadele Chala1; K. Seshagiri Rao2; Swapnil Mishra2; Ankesh Kumar2
1 Indian Institute of Technology Delhi, India; 2 Indian Institute of Technology Delhi
Resumo
The Deccan traps are a large volcanic province located on the Deccan plateau of west-central India between 17-24 N, 73-74 E and one of the largest volcanic features on earth surface erupting from large fissures. In the pre-historic era huge construction of forts, caves took place over Deccan traps whose traces still continues to exist. The famous Ajanta Caves in Maharashtra built in 2nd Century B.C. by carvings on the basalt. Many major projects like dams, communication tunnels (railway and highways), and high rise buildings of Bombay and Pune cities have been built in and on Deccan traps in the past century. Between Mumbai-Pune cities alone 10 communication tunnels are there, and more than a dozen sites where excavation, quarrying and construction were ongoing. Deccan Trap still continues to be an important site for many construction projects and Basalt as an important construction material. Recently many construction activities are going on and the scale and scope of construction is going to increase in future. Not only with respect to construction activities the study of Deccan traps is also important to understand various problems like landslides, slope failures, earthquakes etc that are arising causing danger and damage to life and property. This reveals the importance of the geotechnical studies and investigations to evaluate the geotechnical properties of rocks. However, geotechnical properties of Deccan trap rocks are very scarce. In the present study, Deccan trap volcanic rocks namely compacted basalt, volcanic breccia and tuff are extensively studied through field survey and laboratory experiments. Scanning Electron Microscope (SEM) with energy dispersive X-ray (EDX) analyses were employed to measure the microstructure and material composition of these rocks. Index properties example density, porosity, sonic wave velocity, slake durability were determined as per relevant using international society of rock mechanics (ISRM) codes. The mechanical behavior including point load, compressive, tensile and
Palavras-chave: Volcanic rocks; Deccan trap India; SEM; Geotechnical Property; EDX