Review on Seismic Rehabilitation of a 56Story RC Tall Building having Shear Wall System Based on A Nonlinear Dynamic Performance Evaluation (original) (raw)
Related papers
Structural Design of Tall and Special Buildings, 2010
Tehran Tower is a 56-storey reinforced concrete tall building consisting of three wings with identical plan dimensions each approximately 48 m by 22 m. The three wings are at 120° from each other and have no expansions/seismic joints. This paper contains the consideration of the rehabilitation of the Tehran Tower based on the findings of an exhaustive investigation of the nonlinear performance evaluation efforts. It has tried to show the procedure followed, methodologies utilized and the results obtained for life-safety (LS) and collapse-prevention (CP) evaluations of the building. Moreover, the weak zones of the structure due to analysis results are introduced and appropriate retrofit technique for satisfaction related to LS and CP criteria is presented. In this project, to improve the local behaviour of coupling panels that are regularly located in spine walls, and definitely have been recognized as the most vulnerable structural elements, making use of steel plates that are connected to concrete members by chemical anchors has been used as the best rehabilitation method for this case. Therefore, in the final section, the professional practical method utilized to perform the aforementioned project is explained. Copyright © 2010 John Wiley & Sons, Ltd.
Tehran tower is a 56 story reinforced concrete tall building consisting of three wings with identical plan dimensions each approximately 48 meters by 22 meters. The three wings are at 120 degree from each other and have no expansions/seismic Joints. This paper contains the consideration of the retrofitting of the Tehran tower based on the findings of an exhaustive investigation of the nonlinear performance evaluation efforts. It has tried to show the procedure followed, methodologies utilized, and the results obtained for life-safety and collapse-prevention evaluation of the building. More over the weak zones of the structure due to analyses results are introduced and appropriate retrofit techniques for satisfaction related life-safety and collapse-prevention criteria are also presented.
Evaluation of Seismic Retrofitting Techniques Used in Old Reinforced Concrete Buildings
IOSR Journal of Engineering, 2014
Past earthquakes have emphasized the vulnerability of existing structures which did not satisfy modern seismic design requirements and current engineering standards even though they may have been properly designed and constructed according to earlier codes. Many existing buildings may be inadequate and pose severe risk during seismic events. To mitigate the seismic hazard, existing building should be rehabilitated. The rehabilitation measures to upgrade the capacity of these structures can be performed at some point in their useful lives. The evaluation of the seismic capacity of existing buildings and their deficiencies is essential for the design of a rehabilitation technique. The aim of the evaluation and rehabilitation systems is either for collapse prevention to ensure safety of the occupants or to control the damage to ensure the continuity of operation during and after earthquakes. In this paper several retrofit techniques was evaluated by applicable them on different kinds of existing structures to find the best one will be used for each kind of tested structures. Four retrofit techniques (R.C. walls, steel bracing, column jacket, and column strengthen by 4 steel angles each corner) were tested for each selected four existing structure. By examine each technique on each tested structure, the values of top displacement, top floor acceleration, max. base shear, and period time of first mode were varied by response of each applied retrofit techniques and the minimum response will be the choose as arbitrator between different kinds of used techniques to use it as the optimal technique used to retrofit this structure.
Engineering Structures, 2010
This paper is focused on a proposed seismic retrofitting system (PRS) configured to upgrade the performance of seismically vulnerable reinforced concrete (RC) buildings. The PRS is composed of a rectangular steel housing frame with chevron braces and a yielding shear link connected between the braces and the frame. The retrofitting system is installed within the bays of an RC building frame to enhance the stiffness, strength and ductility of the structure. The PRS and a conventional retrofitting system using squat infill shear panels (SISPs) are used in an existing school and an office building. Nonlinear time history analyses of the buildings in the original and retrofitted conditions are conducted for three different seismic performance levels (PLs) to assess the efficiency of the PRS. The analyses results revealed that the building retrofitted with the PRS has a more stable lateral force-deformation behavior with enhanced energy dissipation capability than that of the one retrofitted with SISPs. For immediate occupancy PL, the maximum inter-storey drift of the building retrofitted with the PRS is comparable to that of the one retrofitted with SISPs. But for life safety and collapse prevention PLs, the maximum interstorey drift of the building retrofitted with the PRS is considerably smaller than that of the one retrofitted with SISPs. Furthermore, compared with the building retrofitted with SISPs, the building retrofitted with the PRS experiences significantly less damage due to the more ductile behavior of the system at the life safety and collapse prevention PLs.
Seismic Performance Assessment of a Tall RC Building Retrofitted with Shear Walls
ASPS Conference Proceedings, 2022
Reinforced concrete (RC) buildings are the most commonly constructed structural forms across the world, and equally common is its susceptibility to damage during any seismic activity. Thus, there is especially a need to correctly assess and study the behaviour of RC structures, particularly the tall RC buildings. Tall RC buildings are increasingly becoming popular nowadays because they provide abundant floor area, where the land available for construction is less due to the rapid urbanisation. The understanding of the seismic performance of such buildings makes the seismic retrofitting procedures convenient and optimal to use. Seismic retrofitting measures are present in plenty for RC structures, each of which is used according to the need or the damage level incurred in the structure or its components. The present study thus focusses on a G+14 tall reinforced concrete (RC) building that was severely damaged during the 2015 Nepal Earthquake and was being retrofitted located at the Hattiban area in Nepal. As recommended in the recently developed guidelines for tall RC structures in IS 16700, the use of a 3D computer model is necessary for the seismic analysis and structural safety assessment of tall buildings. Thus, seismic performance is assessed using the structural analysis program SAP2000 for non-linear analysis of the considered structure. Further, seismic fragilities at specific damage levels are also determined.
SUSTAINABLE STRUCTURAL RETROFITTING OF RC BUILDING BY NON-LINEAR STATIC ANALYSIS
IAEME, 2019
Most of the buildings are affected during the earthquake, as they are designed IS 456:2000 for the gravity loading. So, these buildings may not possess strength, ductility and stiffness. To strengthen these structures, Non-Linear static Pushover Analysis of the building is carried out before and after the retrofitting of the columns of the building in order to find out the effectiveness of the retrofitting. Different retrofitting techniques have been applied such as, Concrete Jacketing, Steel Jacketing and Composite Jacketing. Response Spectrum Method and Non-linear Pushover methods were used to analyse the building models and the results acquired have been compared. Conclusions were made depending on displacement, inter storey drifts, base shear, stiffness, axial load, shear force and moment on the columns.
IRJET, 2020
Old buildings are not earthquake resistant, some of them we cannot dismantle. Retrofitting is technique which is beneficial for such structures.. In the present study G+12 building present in Mumbai (Zone III) is taken for the study. Nonlinear modeling was carried out and building was analyzed using pushover analysis in SAP2000 to identify seismic deficiency. The retrofitting techniques such as shear wall, steel bracing were suggested for improvement. It has been observed that the performance of the building was improved. Thus, it can be concluded that the building retrofitted with shear wall is most effective in present case to improve the performance locally as well as globally
Seismic Evaluation and Retrofit of Existing building in Islamabad
One of the remedies for earthquake hazards reduction is seismic retrofitting. But without using intervention technique which is based on seismic evaluation of the building structure, it may not be possible to improve the seismic performance of the building structures by the use of retrofitting. In this paper the simulation of a building is performed by using nonlinear static "push over" analysis. The said building is 4storey RC building. In this work the real site based demand spectra is compared with the demand spectra of "ATC 40 procedure". The simulation performed is then compared for the sake of evaluation with or without retrofitted structure. For various safety margins the plastic hinges are plotted.
Seismic Evaluation And Retrofit of Existing Buildings
14th European Conference on …, 2010
When evaluating and improving seismic capacity of existing buildings 'seismic safety evaluation' and 'retrofitting' are very important tasks. Engineers evaluate structures with different methods. The presented method combines experimental data and engineering knowledge in order to evaluate seismic safety factors and expected structural performance under strong events. Distinction between the structures with and those without problems are made. This is also a quick way to check the response of structures to expected seismic activities. The method could also be used for choosing the optimal strengthening method and to verify the quality of performed strengthening works. Proposed methodology is explained on the example of two buildings with the explanation of performed strengthening methods. The construction price of retrofitted buildings is compared to the price of demolishing the existing and building a new building.
Seismic retrofitting of existing reinforced concrete building
It is commonly observed that many RC Building collapses during an earthquake are those building which is non –engineered or those RC Buildings which are not constructed as per codal provisions. Some of such buildings have deficiencies in whole structure or individual structural members which don’t have the adequate lateral capacity to counter the seismic demand. Before retrofitting of structure it is required to perform necessary assessments and evaluations of structural member or location deficiencies are found. In this case study, a G+3 storey RC Building is considered for seismic analysis which is located in the zone –IV to calculate the additional seismic strength of structural members like beams and columns. Based on this analysis retrofitting measures are suggested. This analysis is performed by using Stad pro-V8i software. The recommendations are based on IS – 15988, IS – 1893, IS – 13920 and FEMA codes provisions. The method adopted for seismic retrofitting of structures is RC Jacketing.