Behaviour Of Masonry Wall At Corners Under Earthquake

Building structures using masonry is one of the most widely adopted construction practices. However, its seismic performance in earthquake prone regions is a major concern. Majority of the research work which has been carried out for studying the failure pattern of masonry, either targets in-plane failure or out-of-plane failure of walls. However, various survey reports on the damage caused by earthquakes mention about failure of the corner walls of masonry structures such as those situated at the end of a row of structures, in a peculiar manner. Failure in such walls is characterized by the simultaneous overturning of a portion of orthogonal walls which is possible only if lateral loads act along the corners, implying each corner wall is subjected to bidirectional loading. Since the literature addressing such failure, are limited, therefore this study has been carried out to explore the reasons leading to corner failure of masonry structures.In this study, in order to examine the failure pattern at corner in dry masonry structures, finite element (FE) technique was adopted. Various masonry models with varying vertical load were subjected to dynamic loading along the corner to observe their combined effect on failure pattern. This analysis showed the pattern of propagation of crack through the bed joint along under varying dead load conditions. Since it is not possible to perform FE analysis for all the masonry structures, mathematical relations were derived to calculate the limiting acceleration at which corner failure can occur. These relations were obtained by assuming feasible failure mechanisms and applying the concept of limit state analysis. For studying the failure pattern of corner in mortar bonded masonry, the FE approach adopted for dry masonry was extended. Micro-modelling which is mostly adopted for modelling mortar bonded masonry was modified by introducing the concept of equivalent friction to simulate the behaviour of mortar in shear. Cracks were observed to pass through the bricks along with the bed joints which lead to toe crushing due to overturning of failure portion. Through this study an understanding of failure of the corner has been developed.

In the last few decades, a considerable amount of experimental and analytical research on the seismic behaviour of masonry walls and buildings has been carried out. The investigations resulted in the development of methods for seismic analysis and design, as well as new technologies and construction systems. After many centuries of traditional use and decades of allowable stress design, clear concepts for limit state verification of masonry buildings under earthquake loading have recently been introduced in codes of practice. Although this book is not a review of the state-of-the-art of masonry structures in earthquake zones, an attempt has been made to balance the discussion on recent code requirements, state-of-the-art methods of earthquake-resistant design and the author's research work, in order to render the book useful for a broader application in design practice. An attempt has also been made to present, in a condensed but easy to understand way, all the information needed for earthquake-resistant design of masonry buildings constructed using traditional systems. The basic concepts of limit state verification are presented and equations for seismic resistance verification of masonry walls of all types of construction, (unreinforced, confined and reinforced) as well as masonry-infilled reinforced concrete frames, are addressed. A method for seismic resistance verification, compatible with recent code requirements, is also discussed. In all cases, experimental results are used to explain the proposed methods and equations. An important part of this book is dedicated to the discussion of the problems of repair, retrofit and rehabilitation of existing masonry buildings, including historical structures in urban centres. Methods of strengthening masonry walls as well as improving the structural integrity of existing buildings are described in detail. Wherever possible, experimental evidence regarding the effectiveness of the proposed strengthening methods is given. Contents:Earthquakes and Seismic Performance of Masonry BuildingsMasonry Materials and Construction SystemsArchitectural and Structural Concepts of Earthquake-Resistant Building ConfigurationFloors and RoofsBasic Concepts of Limit States Verification of Seismic Resistance of Masonry BuildingsSeismic Resistance Verification of Structural WallsMasonry Infilled Reinforced Concrete FramesSeismic Resistance Verification of Masonry BuildingsRepair and Strengthening of Masonry Buildings Readership: Practising engineers and students.

Brick and Block Masonry - Trends, Innovations and Challenges contains the lectures and regular papers presented at the 16th International Brick and Block Masonry Conference (Padova, Italy, 26-30 June 2016). In an ever-changing world, in which innovations are rapidly implemented but soon surpassed, the challenge for masonry, the oldest and most traditional building material, is that it can address the increasingly pressing requirements of quality of living, safety, and sustainability. This abstracts volume and full paper USB device, focusing on challenges, innovations, trends and ideas related to masonry, in both research and building practice, will proof to be a valuable source of information for researchers and practitioners, masonry industries and building management authorities, construction professionals and educators.

This book deals with earthquake-resistant structures, such as, buildings, bridges and liquid storage tanks. It contains twenty chapters covering several interesting research topics written by researchers and experts in the field of earthquake engineering. The book covers seismic-resistance design of masonry and reinforced concrete structures to be constructed as well as safety assessment, strengthening and rehabilitation of existing structures against earthquake loads. It also includes three chapters on electromagnetic sensing techniques for health assessment of structures, post earthquake assessment of steel buildings in fire environment and response of underground pipes to blast loads. The book provides the state-of-the-art on recent progress in earthquake-resistant structures. It should be useful to graduate students, researchers and practicing structural engineers.

Damage assessment, rehabilitation, decision-making, social consequences, repair and reconstruction; these are all critical factors for considerations following natural disasters such as earthquakes. In order to address these issues, the United States of America and the Peoples Republic of China regularly organize bilateral symposia/workshops to investigate multiple hazard mitigation, particularly with respect to earthquake engineering. This book contains state-of-the-art reports presented by world-renowned researchers at the US/PRC Sympsosium Workshop on Post-Earthquake Rehabilitation and Reconstruction held in Kunming, Yunnan, China, May 1995. The following key areas are addressed: damage assessment of structures after earthquakes; lessons of post-earthquake recovery, rehabilitation and reconstruction, including public policy, land use options, urban planning, and design; issues in and examples of decision-making, and implementation of rehabilitation and reconstruction plans and policies; repair, strengthening, retrofit and control of structures and lifeline systems, post-earthquake socio-economic problems covering issues of relief and recovery; human and organizational behavior during emergency response, and strategies for improvement; real-time monitoring of earthquake response and damage.

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.