IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308 _______________________________________________________________________________________ Volume: 04 Issue: 06 | June-2015, Available @ http://www.ijret.org 164 PROGRESSIVE COLLAPSE ANALYSIS OF AN RC STRUCTURE SUBJECTED TO SEISMIC LOADS IN SLOPING GROUND Shilpa Shree G C 1 , Syed Ahamed Raza 2 1 Post Graduate student, Ghousia college of engineering, Ramnagaram 2 Assistant professor, Ghousia college of engineering, Ramnaram Abstract Progressive Collapse is the spread of initial failure from element to element leading to entire collapse of an structure. It is due to vehicle impacts, fire,earthquakes and natural or man made hazards. Collapse leads to large proprtions of dispropriate triggers in the structures which makes structures incapable of withstanding loads and it leads to collapse of the structure. In this study special moment resisting frame of G+19 story building is modeled using FEM based software( ETABSV9.7). The analysis is carried as per GSA gudelines in zone V having medium soil by linear dynamic and non linear analysis. The story drift and story shears are calculated to know the potential for progressive collapse of an structure. Keywords: Progressive Collapse,Column Removal ,Dynamic Analysis,Push Over Analysis etc… --------------------------------------------------------------------***---------------------------------------------------------------------- 1. INTRODUCTION Progressive collapse is “the spread of an initial local failure from element to element, eventually resulting in the collapse of an entire structure or a disproportionately large part of it.” In this collapse mechanism a single deformation may lead to entire collapse in the structure, it can be inferred that progressive collapse is triggered more due to the sudden removal of column than the collapse of a structure due to earth quake loads. Once a column is removed or made weak, due to man-made or natural hazards, load carried by column removed is transferred to neighbouring columns in the structure, if the neighbouring column is incapable of withstanding the extra load, leads to the progressive failure of adjoining members and finally to the failure of partial or whole structure. The collapsing system continually seeks alternative load paths in order to survive. 1.1 General Stability of a slope can be affected by seismicity in two ways: earthquake and blasting. These seismic motions are capable of inducing large destabilizing inertial forces. In general, three methods of analysis have been proposed for the evaluation of slopes response under such conditions. 1 Pseudostatic Method: The earthquake’s inertial forces are simulated by the inclusion of static horizontal and vertical forces in limit equilibrium analysis. 2. Newmark’s Displacement Method: This method is based on the concept that the actual slope accelerations may exceed the static yield acceleration at the expense of generating permanent displacements. 3. Dynamic Finite Element Analysis: This is a coupled two or three dimensional analyses using appropriate constitutive material model that will provide details of concerning stresses, strains, and permanent displacement. Fig 1 shows the sloping ground 1.2 Progressive Collapse Mechanism Fig 2 shows the mechanism of progressive collapse Progressive Collapse is “the collapse of multiple bays or floors of a structure resulting from an isolated structural failure due to a chain reaction or domino effect”. Any extreme loading that damages structural components such as support beams and columns are subjected to potential cause for progressive collapse. The mechanics of Progressive Collapse has two phases: “Crush-down, whereby gravity