Unreinforced masonry buildings and earthquakes 1 1 introduction this document provides guidance on how to develop programs to reduce the earthquake risks of existing unreinforced masonry buildings. Jan 18, 2016 seismic retrofitting of buildings today, many countries are the victims of severe earthquakes resulting in the loss of lives of human being, animals, destruction of buildings, and many more. Researchers hope to give building owners a number of different options at a. But you may be wondering at this point why retrofitting is necessary.
In addition, the tier 1 checklists have been significantly modified and reorganized. This nextgeneration standard combines the evaluation and retrofit process and puts forth a threetiered process for. Seismic retrofitting techniques linkedin slideshare. Retrofitting of concrete course documentation structures. This publication is downloadable on the internet as a pdf file at. By contrast, 16% of the pre1981 buildings collapsed or were heavily damaged. Seismic qualification ev entually leads to retrofitting of the deficient structures. Pushover analysis and seismic retrofitting using shear. Part 2 of this manual provides guidance on the assessment and retrofitting of other typical highway structures. Softstory softstory structures are common among apartment buildings, characterized by open parking on the ground floor and dwelling units built above. Sponsored by the structural engineering institute of asce. Seismic evaluation and strengthening of existing buildings. Review of documents on seismic strengthening of existing.
The existing lowrise and mediumrise buildings in the world consist of large number of reinforced concrete rc frame buildings designed only for gravity loads lakshmanan 2007. Review of retrofitting methods to reduce seismic vulnerability of buildings, with particular reference to hospitals and medical facilities dina dayala, carmine galasso, stylianos minas and viviana novelli june 2015. Softstory softstory structures are common among apartment buildings, characterized by open parking on. Currently, there are still innumerable buildings in portugal that illustrate the various traditional earth construction techniques. Compilation of adobe, masonry and rcc feb 9, 2017 given that nepal lies in a seismicallyvulnerable area, prone to the kind of natural disaster that occurred in 2015, it is imperative that buildings are designed with seismic resilience in mind. Finally, some of the characteristic relevant data such as the year of construction, build ing use, building value, importance class, seismic zone, ground type. Challenges in building retrofitting and recommendations for expanding units. These performance objectives can be such as limiting story drift, minimizing. However, when subjected to strong ground motions, the buckling of the braces results in loss of lateral stiffness and strength of the structural system. Correctly explain the background behind the current standards for seismic evolution and retrofit of buildings by citing lessons learned from past earthquakes. Buildings exceeding three stories in height and any threestory building with cripple wall studs exceeding 14 inches 360 mm in height.
Analysis seismic retrofitting of building using sap2000. The memberlevel retrofit approaches include the addition of concrete, steel, or fiber reinforced polymer frp jackets for use in confining rc columns and joints. Seismic retrofitting definition, techniques using modern. Seismic retrofitting of an existing structure amritha ranganadhan department of civil engineering tist, arakkunnam, eranulam, kerala, india anju paul department of civil engineering tist, arakkunnam, eranulam, kerala, india abstract retrofitting an existing building is often considered to be more costeffective than constructing a new building. Seismic conceptual design of buildings basic principles. Column jacketing column retrofitting is often critical to the. Seismic evaluation and retrofit of existing buildings describes deficiencybased and systematic procedures that use performancebased principles to evaluate and retrofit existing buildings to withstand the effects of earthquakes. Proposed methodology is explained on the example of two buildings with the explanation of performed strengthening methods. Request pdf seismic retrofitting of historical buildings monuments have been preserving cultural identity of ancient people. Codebased procedures for seismic safety assessment and retrofit.
Seismic evaluation and retrofitting of buildings and. Pdf evaluation of seismic retrofitting techniques used in old. If you live in an area prone to earthquakes, its important that the structural frame of your home is strong enough to absorb an earthquakes energy see continuous. Finally, baseisolation by elastomeric bearings fig. Seismic design of buildings worked examples worked examples presented at the workshop ec 8. Retrofitting of existing structures with insufficient seismic resistance accounts for a major portion of the total cost of hazard mitigation. Seismic retrofitting of reinforced concrete buildings using. With better understanding of seismic demand on structures and with our recent experiences with large earthquakes near urban centers, the need of seismic retrofitting is well acknowledged. Seismic evaluation and retrofitting are undertaken for the life line buildings, such as hospitals, police stations, fire stations, major administrative buildings, schools, educational buildings, historical monuments etc. Earthquake mitigation is an important field of study from a long time now.
A survey of methods and techniques used for seismic. Seismic assessment and retrofitting of existing buildings, according to the eurocode 8 part 3. Seismic retrofitting guidel ines of buildings in nepal. Pdf seismic retrofitting of reinforced concrete buildings using.
Evaluation of building retrofitting alternatives from sustainability. In the southern region of the country, the dominant construction technique was rammed earth. Index seismic retrofitting manual for highway structures. I to investigate the effects of earthquake forces on buildings and literature search on earthquake resistant design ii to evaluate the feasibility of seismic evaluation of buildings and advantages of applying the retrofit measures developed for. Seismic evaluation and retrofit of existing buildings standards. Next, to compare the response of the baseisolation systems in the cases considered above ebi, efbi, fpbi structures, the maximum horizontal. Also, changes in service conditions, often made arbitrarily, may lead to substantial changes in the structural behaviour resulting in a degradation of the. The need for seismic retrofitting of an existing building can arise due to several reasons like. This nextgeneration standard combines the evaluation and retrofit process and puts forth a three. Generally, the structural retrofit of concentrically braced frames improved the seismic resistance of the building and it can be considered in the retrofit of moment. Seismic retrofitting manual for highway structures. Seismic evaluation retrofitting of existing building. Seismic retrofitting of structures bundesamt fur umwelt. Cripple walls that exceed four feet 1234 mm in height.
Essential to reduce hazard and losses from nonstructural elements. As known, the main advantage of using seismic isolation systems for protection of historic buildings is that the retrofitting works can be. Though not applicable to all building types, the document also discusses some costeffective strengthening schemes for existing older buildings identified as seismically deficient during the evaluation process. Correctly explain the fundamental difference between new design standards and the standard for evaluation and retrofit of existing buildings. Seismic evaluation and retrofit of existing buildings. It is characteristic that in kobe 1995, where the death toll approached 6300, only 6. Analytical study on seismic retrofitting of reinforced. The use deficiencyonly procedures tier 2 have been greatly expanded to regular buildings of greater heights. So, it is high time for the civil engineers to take this issue as a serious matter and they must think of some alternatives of saving human lives as well.
Strengthening and retrofitting of existing structures 10. Part 2 retaining structures, slopes, tunnels, culverts and roadways this report is available only in pdf format. The seismic zone map of indian subcontinent emphasis that more than 60% of land is under severe to moderate earthquake and approximate habitat requirement is 2025 lakhes of buildings in each year. Retrofitting with externally bonded advanced composites fibre reinforced polymers frps, to which the present bulletin is devoted, is cleaner and easier to apply than conventional retrofitting.
Using seismic isolation systems for retrofitting historic. Seismic retrofit guide d uring an earthquake, the strength of a home is put to the test. Introduction earthquake creates great devastation in terms of life, money and failures of structures. In comparison to the above, retrofitting shear wall techniques have opened new possibilities of effective structural upgradation. Thus, it is of critical importance that the structures that need seismic retrofitting are identified correctly, and an optimal retrofitting is conducted in a cost effective fashion. Relatively speaking, seismic retrofitting of buildings is still a new activity for most structural engineers. Retrofitting old buildings to make them earthquake safe. Oct 21, 2014 retrofitting old buildings to make them earthquake safe. The beneficial influence of regularly distributed masonry infills mis, reducing the deformation demand and enhancing the energy dissipation capacity of the bare structure, is not generally taken into account in the seismic assessment of existing buildings.
Design objective retrofitting a historic structure in salt lake city to improve its ability to withstand seismic events can be carried out while minimizing negative impacts upon historic features and building materials. Assessment of prototype buildings etty conservation institute 4. Under such circumstances, seismic qualification of existing buildings has become extremely important. As known, the main advantage of using seismic isolation systems for protection of historic buildings is that the retrofitting works can be performed at the basement or roof levels. Seismic retrofitting of existing structures pdxscholar portland. However, irregularities in elevation due to softstoreys or unsymmetrical layout of the masonry infills can produce. Download code analysis seismic retrofitting of building using sap2000. Baseisolation systems for the seismic retrofitting of r. Houses built prior to 1974 were not required to be anchored during construction.
Indian buildings built over the past two decades are deficient because of items b, c, and d above. Jan 29, 2016 download code analysis seismic retrofitting of building using sap2000. This often limits the application of base isolation to 1 special buildings, such as certain industrial, research, public and hospital buildings that. Pushover analysis and seismic retrofitting using shear walls. Seismic evaluation and retrofit of existing buildings asce. Seismic retrofitting of historical buildings request pdf. Steel braces are often used for seismic retrofitting of rc buildings. Buildings basic principles for engineers, architects, building owners, and authorities biel 2002, 81p.
Review of retrofitting methods to reduce seismic vulnerability of buildings, with particular reference to hospitals and medical facilities dina dayala, carmine galasso, stylianos minas. Retrofitting is making changes to an existing building to protect it from flooding or other hazards such as high winds and earthquakes. That said, here are some basic approaches to retrofitting applied to various types of structures found to be vulnerable to damage or collapse in a major earthquake. Seismic retrofitting approaches to 5 common building types. Seismic retrofitting of constructions vulnerable to earthquakes is a current problem of great political and social relevance. Pdf the seismic retrofitting of reinforced concrete buildings not designed to withstand seismic action is considered. Assessment of existing structures using response history analysis. Seismic retrofitting of buildings linkedin slideshare. Concept of retrofitting retrofitting is technical interventions in structural system of a building that improve the resistance to earthquake by optimizing the strength, ductility and earthquake loads. This thesis also intends to give out the fundamental notions in part 1 of eurocode 8, which are useful for the assessment and retrofit of buildings. A comparative study on seismic retrofitting researchgate keywords.
Performancebased seismic design for tall buildings performancebased seismic design pbsd is a structural design methodology that has become more common in urban centers around the world, particularly for the design of highrise buildings. For buildings with large seismic deficiencies, a combination of conventional and frp strengthening techniques may prove to. For this reason, the cost of base isolation is often significantly higher than alternative retrofitting methods. Seismic retrofitting is the modification of existing structures to make them more resistant to seismic activity, ground motion, or soil failure due to earthquakes. Buildings with a lateral system using poles or columns embedded in the ground. Ground forces try to tear the home apart and in many cases, cause severe damage. June, 2014 when citing these guidelines the following citation should be used. Seismic retrofitting of deficient rc buildings concept of pushover analysis sudhir k. Afterwards, building is virtually retrofitted considering architectural plan and using common retrofitting methods for satisfying current seismic code requirements. You have already seen an example of these changes, and youll learn more in the following chapters. Researchers hope to give building owners a number of different options at a variety of price points to. Ceb 1995 concepts including strengthening, repairing and remoulding newman, 2001 it is an upgrading of certain building system, such as mechanical.
Seismic retrofitting guidelines of buildings in nepal. Part 1 of this manual focuses on highway bridges, and is a replacement for the federal highway administration fhwa publication seismic retrofitting manual for highway bridges which was published in 1995 as report fhward94052. In the decade following the 1974 code revisions, houses were being built by contractors with little to no knowledge of how to properly anchor a house, leaving homes built during this code cycle still vulnerable to seismic activity. To ensure the safety and security of a building, employees, structure functionality, machinery and inventory. National disaster management authority government of india ndma bhawan a1, safdarjung enclave new delhi 110029 isbn no. Among various methods of retrofitting, the most suitable method for a particular building can be identified after performing a structural assessment. National disaster management guidelines seismic retrofitting of deficient buildings and structures a publication of. So, it is high time for the civil engineers to take this issue as a serious matter and they must think of some. As the following chapters will show, this building type is typically the most seismically. Innovative materials for seismic and energy retrofitting of the. Thus, seismic retrofitting of rc buildings with braces that may potentially buckle does not seem to be a feasible retrofitting solution. Seismic evaluation of existing buildings standards. The buildings belong to the institute autonomo case popolari iacp of syracuse.
The retrofitting of existing buildings for seismic. General a higher degree of damage in a building is expected during an earthquake if the seismic resistance of the building is inadequate. The paper ends with a description of the seismic retrofitting of two reinforced concrete residential buildings in the village of solarino, near syracuse, in sicily. This thesis describes the process for retrofitting a building for seismic criteria. Seismic retrofitting techniques for concrete structures. Seismic retrofitting of buildings seismic retrofitting is the modification of existing structures to make them more resistant to sei. Necessity of seismic evaluation building because of lack of timely revise code, lack of timely revision of seismic zone map. Review of seismic strengthening of buildings iitkgsdmaeq07v1. Seismic assessment and retrofitting of buildings the only part in the whole set of 58 eneurocodes that deals with existing structures 1st standard in europe on seismic assessment and retrofitting of buildings no experience in european practice w codified seismic assessment and retrofitting. The construction price of retrofitted buildings is compared to the price of demolishing the existing and building a new building. Horizontal forces of earthquakes cause damage to historic structures. Many existing buildings do not meet the seismic strength requirement. Many existing buildings may be inadequate and pose severe risk during seismic events. Manual on retrofitting of existing vulnerable school buildingsassessment to retrofitting part i 4 2.
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