Abstract:
Construction of tall and massive structures has become present need in overcrowded urban areas in order to fulfill the requirements of modern society. In India with the rapid urbanization, deep excavation for structures surrounded by congested area and their effect on adjacent buildings has been a critical issue, mainly related to the soil displacements. It is common to construct underground structure nearby existing buildings in urban areas. The appropriate support system to the deep excavation area in urban locality always depends upon the geotechnical conditions of the works site and safety of the excavation surroundings and neighboring structures. The rapid mass transportation system in urban area widely referred to as Metro Rail, has seen significant growth in India in the recent years. Nowadays, many metropolitan cities are experiencing the need for rapid transport system like metro rail for meeting their routine mobility requirements. Metro rail project includes construction of elevated and at grade viaduct and Metro Stations as well as underground. The metro structures involved deep excavation for foundations which induces the stresses and thereby alters the existing equilibrium and thus may affect stability of neighboring structures which needs to be protected considering safety point of view. Many factors affect the stability of excavation such as soil strength, ground-water, building surcharges, construction methods and also construction techniques. Hence, design and execution of deep excavations become one of the important challenging tasks of any geotechnical engineer in the modern era. Further, it is important to control the ground movement in order to prevent the failure of excavations. This involves specialized foundation technologies, usage of new methodologies in underground construction, safety and monitoring systems. In this paper the methodology used for protecting adjoining structures due to deep excavation and type of construction provided for Nagpur Metro station is studied.
Abstract: Theme 1