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Ground vibrations during earthquakes cause deformation and forces in the structures. The earthquake of the late 19th and early 20th centuries triggered several early advancements in science and engineering. The Bhuj earthquake of 2001 was the first instance of engineering causing the collapse of modern multi-storey buildings in India. The main principle used in the seismic design of the structure is capacity design. This principle allows the design of dissipative members, where the energy dissipation will be concentrated during a seismic event, while the non-dissipative members are protected from failure by providing them with a level of over strength such that they can resist the maximum force developed by the plasticization in the dissipative zone. Capacity design principles are; Global plastic mechanism of structure, Identification of dissipative and non-dissipative zones in the structure, and Provision of proper detailing to ensure maximum ductility for dissipative zones. In recent days because of rapid population growth, civil engineering structures like high-rise buildings, long-span bridges, huge industrial buildings, etc., have become more common. These structures are prone to damage during natural disasters and the consequences of failure are catastrophic. Hence some precautions need to be taken during the design of structures. However, these structures cannot be made completely safe against such calamities. Some extraordinary situations may cause damage to the structures or may lead to collapse. So it is important to make the structure safe even after extraordinary situations of natural disasters. Structures can be protected against natural hazards by using a lateral load resisting system or structural damping system or energy dissipating system. Steel LFRS has been used in all forms the structures to resist lateral forces like earthquake and wind forces. This system provides various advantages such as cost reduction, speed of construction, reduced foundation cost, and increased ductility of the structure. Using steel as construction material economic designs can be achieved that provide life safety for the occupants. Commonly used structural typologies for a steel building to resist the lateral forces are, Moment resisting frames (MRF), Braced frames, and Steel plate shear walls.

The ground motions observed at the surface due to artificial source (exploration seismology) or natural source (earthquake seismology) are affected by source characteristics, medium properties and site conditions. The medium properties are related to the attenuation of seismic waves propagating between source and receiver. The attenuation properties of a medium affect the amplitudes of ground motions at various distances from the source. Subsurface factors attributing to the seismic wave attenuation are geometrical spreading, absorption, inter-bed multiples generated by thin layering, diffractions and the focusing or defocusing effects of the reflector curvature or velocity. Among these subsurface factors, absorption reveals geological information, which includes attenuation of both intrinsic and scattering effects. Seismic wave attenuation plays a pivotal role in exploration seismology as well as in earthquake seismology. In exploration, it helps in improving the seismic resolution for reliable interpretation of hydrocarbon prospects and can be used as an attribute for delineation of the reservoirs. In earthquake seismology, it correlates with regional heterogeneities such as major folds, faults or near-surface complexities and helps in categorizing the scale of tectonic activity in the region. Seismic waves undergo attenuation and dispersion attributing to the frictional losses or the scattering while passing through the dissipative earth. The frictional losses are often termed as intrinsic attenuation, which occurs due to the relative movement of grains or fluids in the rock matrix. The intrinsic properties of the medium such as grain type, architecture, porosity, fluid type, viscosity, permeability, saturation and pressure are usually accountable for these losses in sedimentary rocks. Scattering attenuation is because of random heterogeneities in the near surface or weathered basalts and by the layering effects such as stratigraphic filtering. Both intrinsic and scattering losses eventually lead to phase distortion, degradation of seismic resolution and poor imaging below absorptive zones.

Building with earthquakes is a familiar yet persistent design problem for resilient construction on all continents. This book elaborates on various factors for earthquake-resilient architecture in six thematic chapters that explore the design strategies of lightness, quickness, exactitude, visibility, multiplicity and consistency. These factors allow designers to develop contextual solutions that marry technical know-how with social and cultural understanding, ranging in scale from buildings to furniture and urban master plans. 120 case studies from roughly 30 countries, including some highly prestigious buildings, provide a comprehensive overview of the different design strategies.

The unique compendium teaches beginners how to perform nonlinear finite element (FE) analysis by following a series of step-by-step examples and basic programming method using OpenSees. The scope of the book includes nonlinear FE analyses of reinforced concrete frame shear wall structures, liquefiable soils, soil-structure interaction systems, fluid-solid coupling systems, high-speed railway systems, as well as introduces the sensitivity, reliability, optimization, peridynamic (PD) analysis, and the integration of OpenSees with other softwares. This must-have reference also teaches users how to program by adding simple material and element models, as well as PD algorithms in OpenSees.

With the increased rate of socio-economic activities due to fast-growing population and urbanization, disasters especially earthquakes, even today lead to large-scale destruction and loss of life. Urbanisation and rapid development of cities depend upon their location in regard to ecology, geology, demographic structure, economic opportunities and land use pattern. Thus, with people moving towards urban centers, the scale of risk and vulnerability is ever increasing. In developing countries like India, the socio-economic setup of cities becomes imbalanced mainly due to unauthorised construction taking place, lack in the enforcement of guidelines and forcing the poor to live in the most vulnerable areas within it.

Master's Thesis from the year 2015 in the subject Engineering - Geotechnology, grade: 9.44, , course: Masters (Structural Engineering), language: English, abstract: The present study investigates the seismic behavior of multi-story building using damping devices strategically located within the lateral load resisting elements. It concentrates on a retrofitting strategy with passive energy dissipation device known as Fluid Viscous Damper (FVD) which will be applicable to new design as well as retrofitting existing buildings to ensure seismic safety by fitting damping devices which can transform a wall panel into a damping element. The first study involves analysis of a nine-story model having cut-outs and the use of the dampers of different configuration in these structures. The second study involves the use the diagonal brace configuration dampers provided in the cutout sections of 2D 9, 18, 27 storey structures and 3D 27 storey with core wall structure at three consecutive story levels each. For the second study, the cut out locations is varied depending on their relative positions. The relative position is the ratio of the total height of the structure to the upper edge of the topmost cut-out.These structures were initially modeled and time history analysis was performed on the structure without FVD and the structure retrofitted with FVD. Three different ground motions were used for the analysis. Results of the un- retrofitted structures are then compared with a retrofitted structure in terms of peak story displacements, roof accelerations, and pseudo-spectral accelerations. Study shows that there has been a significant reduction in seismic demands for a structure retrofitted with FVD in terms of peak storey displacements, pseudo-spectral accelerations and roof accelerations when the dampers are placed at lower three cut outs i.e. with high relative position. It is also observed that damping coefficient value obtained is least for upper toggle-brace configuration out of the four different damper configurations and with maximum reduction compared to other configurations. For modeling and analysis purpose the software SAP2000® is used.Through the study it could be concluded that FVD significantly reduces the seismic demands of the structure in terms of peak storey displacements, pseudo-spectral accelerations and roof accelerations. This suggests that FVDs can be efficiently used in retrofitting. Also damping coefficient value obtained is least for upper toggle-brace configuration out of the four different damper configurations suggesting this is the most efficient configuration for retrofitting.

Seismic Evaluation, Damage, and Mitigation in Structures covers recent developments in the area of seismic performance assessment of structures. Earthquakes are one of the main natural hazards that could directly cause damages to or collapse of structures, resulting in significant economic and human life losses. In the event of an earthquake where many buildings and infrastructure components are not able to function afterward, or if extensive repair and associated disruption are needed, it can be very costly and take a long time to resolve. Divided into three parts, the book reviews and discusses earthquake-induced damage evaluation in structures, repair of structural and non-structural components, and seismic damage mitigation strategies. With contributions from the leading experts in the field, this book is for earthquake and structural engineers and PhD students studying civil engineering and for those who understand that design and damage mitigation of structures that have limited structural or non-structural damage in a seismic event can be easy to inspect and repair for quick reoccupation.

An earthquake is the shaking of the surface of the Earth, resulting from the sudden release of energy in the Earth's lithosphere that creates seismic waves. Earthquakes can range in size from those that are so weak that they cannot be felt to those violent enough to toss people around and destroy the whole cities. At the Earth's surface, earthquakes manifest themselves by shaking and sometimes displacement of the ground. When the epicenter of a large earthquake is located offshore, the seabed may be displaced sufficiently to cause a tsunami. Earthquakes can also trigger landslides and occasionally volcanic activity. Earthquakes are caused not only by rupture of geological faults but also by other events such as volcanic activity, landslides, mine blasts, and nuclear tests. This book addresses the multidisciplinary topic of earthquake hazards and risk, one of the fastest growing, relevant, and applied fields of research and study practiced within the geosciences and environment. This book addresses principles, concepts, and paradigms of earthquakes, as well as operational terms, materials, tools, techniques, and methods including processes, procedures, and implications.