For each retrofit stage, several details and construction photos are presented. The main aim in retrofit design of the building is to minimize the seismic demands on the rc shear walls by optimizing their arrangements in the plan of the building. The goal of the mandatory retrofit programs, under the ordinance, is to reduce these structural deficiencies and improve the performance of these buildings during earthquakes. Commentary for seismic rehabilitation of buildings atc 1995 were developed by the federal emergency management agency fema to provide performancebased recommendations for retrofitting existing buildings. Seismic design of buildings worked examples worked examples presented at the workshop ec 8.
Seismic retrofitting techniques for historic adobe buildings. The mandatory soft story retrofit program mssp was created in 20 as a multiyear communitybased effort led by the earthquake safety implementation program and enforced by the department of building inspection to ensure the safety and resilience of san franciscos housing stock through the retrofit of older, woodframed, multifamily buildings with a softstory condition. Seismic retrofitting is the modification of existing structures to make them more resistant to seismic activity, ground motion, or soil failure due to earthquakes. Between 2015 and 2017, techminho studied four prototypes of historic earthen. The standard presents a threetiered process for seismic evaluation according to a range. Ppt on retrofitting concrete beam structure free 30. Pdf base isolation for seismic retrofitting of structures.
Feb 09, 2017 seismic retrofitting guidelines of buildings in nepal. Pdf seismic retrofitting of reinforced concrete buildings using. 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. Each building has different approaches depending on the structural deficiencies. Techniques of seismic retrofitting for concrete structures. A retrofit for this type of building generally includes adding roof to wall anchors and continuity ties throughout the building. Buildings designed to meet the modern seismic codes, but deficiencies exist in the design andor construction. Buildings free fulltext nonlinear modelling of curved. Foundation retrofitting underground wall beam addition method. Mandatory soft story program department of building.
Damage to unreinforced masonry buildings is dangerous. Techniques of seismic retrofitting for concrete structures core. This site is like a library, use search box in the widget to get ebook that you want. Pdf evaluation of seismic retrofitting techniques used in old. The seismic evaluation process consists of investigating if the structure meets the defined. Seismic retrofit services srs retrofit san fernando valley. Three specific structures such as historical buildings, bridges, and liquid storage tanks are selected to investigate the effectiveness of the base isolation in seismic retrofitting. Conclusion seismic retrofitting techniques for concrete structures. An approach to retrofitting in which complete analysis of the response of the building to seismic hazards is performed, implicitly or explicitly recognizing nonlinear response.
Seismic retrofitting guidelines of buildings in nepal. Earthquake load is generated from the site seismicity, mass of the structures, important of buildings, degree of seismic resistant, etc. Planning and engineering guidelines for the seismic. Seismic retrofitting of structures bundesamt fur umwelt. Download pdf the principles of seismic retrofit refer to the goals, objectives and steps. This paper presents a comprehensive overview of the techniques available for the seismic retrofitting of adobe buildings. Seismic evaluation and retrofit of existing buildings. Modeling of prototype buildings summarizes the methodology and presents the conclusions of the modeling phase carried out by tecminho, university of minho, portugal, as part of the seismic retrofitting project srp between 2015 and 2017, techminho studied four prototypes of historic earthen architecture in peru in their current conditions and in retrofitted configurations. The seismic retrofitting of reinforced concrete buildings not designed to withstand seismic action is considered. Pdf the seismic retrofitting of reinforced concrete buildings not designed to withstand seismic action is considered. It has matured in the recent years to a highly reliable technology. A retrofitting to these types of concrete buildings involves the installation of combined modes such as concrete shear walls, caissons, steel columns and other types of strengthening systems. Seismic design, assessment and retrofitting of concrete.
Global retrofitting local retrofitting the retrofitting in which we use to repair only the structural elements is called local retrofitting. Earthquake prone buildings wellington city council guide. There are many seismic retrofitting techniques available, depending upon the various types and conditions of structures. Many existing buildings may be inadequate and pose severe risk during seismic events. It analyzes these techniques viability from a structural engineering standpoint, and evaluates their suitability in the context. Seismic evaluation and retrofit of unreinforced masonry building with flexible diaphragms seismic evaluation of a. Seismic risk factors courtesy of utah division of state. To ensure the safety and security of a building, employees, structure functionality, machinery and inventory essential to reduce. Many strengthening techniques have been introduced aimed at improving the structural performance of existing structures that, if properly designed and applied, provide an effective contribution. Need of retrofitting in existingearthquake vulnerable buildings buildings have been designed according to a seismic code, but the code has been upgraded in later years. But, the expertise needed is not available in the basic level. A reliable numerical evaluation of the nonlinear behaviour of historical masonry structures, before and after a seismic retrofitting, is a fundamental issue in the design of the structural retrofitting. It also provides certain aspects of computer software modeling against seismic loads and shows the necessity of seismic upgrading in a steel momentframe building.
Nov 11, 2011 seismic retrofitting definition it is the modification of existing structures to make them more resistant to seismic activity, ground motion, or soil failure due to earthquakes. 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. Assessment of prototype buildings etty conservation institute contents volume 1 project participants v chapter 1 background 1. Both of these projects developed similar standardized performance level definitions, which are shown in figure 2. The need for retrofitting of old buildings emanates from their substandard design in terms of both earthquake resistance and thermal insulation. Seismic design, assessment and retrofitting of concrete buildings. The retrofitting is examined with an application to a 64m highrise src steel framed reinforced concrete building built in 1970. In parts of the state vulnerable to seismic events, the resilient building. Using seismic isolation systems for retrofitting historic. This is revealed during strong earthquakes that result in collapses. Advanced design examples of seismic retrofit of structures. In japan, more than 17 existing buildings has been executed or under planning of retrofit. Innovative materials for seismic and energy retrofitting of.
Seismic evaluation and retrofit of existing buildings, standard ascesei 4117, describes deficiencybased and systematic procedures that use performancebased principles to evaluate and retrofit existing buildings to withstand the effects of earthquakes. This may achieve the retrofit objectives for buildings with lightly insufficient seismic resistance. If instead, r building is vulnerable to the design earthquake. 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. For the collection of examples, buildings were selected to be as different and extensive as possible according to building use, structure type, ground type, seismic. Sponsored by the structural engineering institute of asce. Seismic evaluation and strengthening of existing buildings. The seismic retrofit of historic buildings is as much an art as it is a science.
The following guidelines are prescriptive minimum standards based on the 2006. Seismic evaluation and retrofitting of buildings and structures. Seismic isolation technology is very effective to retrofit existing buildings while they are in service. Seismic retrofit consists of adding roof to wall anchors and continuity ties in its simplest form. To mitigate the seismic hazard, existing building should be rehabilitated. The main benefit of retrofitting with composites is the increase in deformation capacity of the building, and in its load capacity to an extent.
When masonry debris falls, it is potentially lethal. Ribakov ariel university center of samaria, ariel, israel abstract historical buildings are usually characterised by relatively low height and their natural vibration period is rather low. This thesis describes the process for retrofitting a building for seismic criteria. Innovative materials for seismic and energy retrofitting of the. June, 2014 when citing these guidelines the following citation should be used. Because there are many earthquakes in japan, buildings must not only be able to be simply repaired, but also be strengthened. Seismic retrofitting techniques for concrete structures focuses procedures to improve evaluation of seismic vulnerability of reinforced concrete buildings and provide innovative retrofitting techniques such as base isolation and mass reduction. The need of seismic retrofitting of building arises under to circumstances. Buildings built prior to 1985 need to be looked at for possible strengthening and buildings prior to 1975.
The problems faced by a structural engineer in retrofitting earthquake damaged building. 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. Building materials used in seismic retrofitting should be located on the interior andor blended with existing architectural features. Seismic retrofit contractor oaklandberkeleysan jose. 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. Therefore, seismic retrofitting of building structures is one of the most important aspects for mitigating seismic hazards especially in earthquakeprone countries. Pdf seismic retrofitting techniques for concrete structures. Due to the variety of structural condition of building, it is hard to develop typical rules for retrofitting. Example 2 is a chapel in a university built in 1920. Guidelines for seismic evaluation of existing buildings. Bay area retrofit does not recommend performing a retrofit without the guidance and supervision of experienced and knowledgeable retrofit professionals, and is not responsible for costly errors, injuries, or earthquake.
Strategies and collection of examples in switzerland foen 2008 10 1 dealing with existing structures in recent years the seismic requirements in building standards have been getting distinctly more rigorous. After briefly introducing how seismic action is described for design purposes, methods for assessing the seismic vulnerability of existing buildings are presented. The getty seismic adobe project gsap was first discussed in october of 1990 at the sixth international conference on earthen architecture in las cruces, new mexico. Tesfamariam s, goda k eds handbook of seismic risk analysis. 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. The retrofit techniques are also applicable for other natural hazards such as tropical cyclones, tornadoes, and severe winds from thunderstorms. The goal with each method is to strengthen junctions of the structure, which provides increased strength and resilience. The retrofitting of existing buildings for seismic. Seismic retrofitting is a suitable technology for protection of a variety of structures. Index seismic retrofitting manual for highway structures. Seismic retrofit with the addition of new shear walls to an existing frame design of new rc shear walls on the perimeter of a seismically deficient fivestorey building of example 1 is illustrated as a retrofit option.
Seismic retrofitting techniques for concrete structures. This strengthens the connections that have found to be inadequate in older buildings. This is the third in a series of gsap volumes that began in 1996 with the publi. This nextgeneration standard combines the evaluation and retrofit process and puts forth a three. The seismic and energy retrofitting of existing european buildings with. Seismic retrofitting of constructions vulnerable to earthquakes is a current problem of great political and social relevance. Seismic assessment and retrofitting of existing buildings, according to the eurocode 8 part 3. The retrofitting of existing buildings for seismic criteria. Reflecting the historic first european seismic code, this professional book focuses on seismic design, assessment and retrofitting of concrete buildings, with thorough reference to.
Handbook on seismic retrofit of buildings download ebook. The seismic and energy retrofitting of existing european buildings with innovative materials is addressed in this report. Alameda is renowned for its historic woodframed architecture, and there are many buildings in the city that are classified as softstory where open store fronts or garages are tucked under the building. Asce 4117 seismic evaluation and retrofit of existing buildings 2017 updated from asce 41 significant changes were included for the basic. Varios terms are associated to retrofotting with a marginal differnce like repair, strengethening, retrofitting, rehabilitation, reconstruction etc.
For buildings with large seismic deficiencies, a combination of conventional and frp strengthening techniques may prove to be an effective retrofitting solution. Part 2 of this manual provides guidance on the assessment and retrofitting of other typical highway structures. Seismic rehabilitation of buildings fema 356 provides guidance for evaluating the seismic performance of existing structures and determining the necessary retrofitting methods to achieve the performance objectives asce 2000. Introduction to retrofitting retrofitting is any change made to an existing structure to reduce or eliminate the possibility of damage to that structure from flooding, erosion, high winds, earthquakes, or other hazards. Using seismic isolation systems for retrofitting historic buildings i. However, for detailed technical guidance on seismic retrofitting, reference should be made to fema 547 fema, 2006 which applies to all types of buildings and for all types of use and occupancy. Seismic retrofitting of existing structures pdxscholar portland. Seismic retrofitting techniques linkedin slideshare. Click download or read online button to get handbook on seismic retrofit of buildings book now. 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. Some methods are additions of rc structural walls, use of steel bracings, seismic isolation, use of frp and supplemental energy dissipation devices dampers. Reflecting the historic first european seismic code, this professional book focuses on seismic design, assessment and retrofitting of concrete buildings, with thorough reference to, and application of, eneurocode 8.
The seismic retrofitting of a building is usually the result of a process that, through analysis and evaluation of the current state of its. This seismic retrofit guide is designed to promote public safety and welfare by reducing the risk of earthquake induced damage to existing homes. The primary purpose of this document is to provide a selected compilation of seismic rehabilitation techniques that are practical and effective. It analyzes these techniques viability from a structural engineering. Commercial seismic retrofitting california foundation works. It is evident that the building can withstand the seismic action if and only if r.
Or concepts including strengthening, repairing and increasing the seismic types of retrofitting there are two types of retrofitting used for repairing the structures. Using seismic isolation bearings and the like to reduce the seismic energy applied to the structure in order to improve its various performance values during an earthquake. After many kinds of survey, we proposed three ideas of seismic retrofitting and selected base isolation. A seismic retrofit for this type of building typically involves adding rooftowall connections, continuity ties, and installing a new plywood overlay on the roof.
Seismic retrofitting consists of one or more structural interventions developed to improve the resistance of existing buildings to seismic loads. The risk of a major earthquake is always present in alameda, just as it is in much of california. The focus of this manual is on retrofitting buildings that are subject to flooding. 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. National disaster management guidelines seismic retrofitting of deficient buildings and structures a publication of. National disaster management authority government of india ndma bhawan a1, safdarjung enclave new delhi 110029 isbn no. Seismic evaluation and retrofit of existing buildings 4117. Modeling of prototype buildings summarizes the methodology and presents the conclusions of the modeling phase carried out by tecminho, university of minho, portugal, as part of the seismic retrofitting project srp.
477 1272 431 371 352 129 1014 1159 1050 249 20 1076 1184 351 755 1536 515 88 428 124 727 822 659 592 481 1524 1619 168 561 632 719 668 155 979 121 997 136 1230