• Title/Summary/Keyword: reinforced buildings

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Seismic Performance Evaluation of Reinforced Concrete Moment Framed Low-story School buildings (철근콘크리트 모멘트 골조 저층형 학교건축물의 내진성능 평가)

  • Hwang, Ji-Hyun;Park, Tae-Won;Han, Ju-Yeon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.9
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    • pp.4580-4586
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    • 2013
  • Many school buildings are not applied seismic code because of small size structures. But it must be designed to show enough structural performance when subject to earthquake due to the fact that most of school buildings are generally used as public shelters when the natural disasters. In this study, the seismic risk of the reinforced concrete school building structure which is the most common types of school structures was evaluated by using the seismic performance evaluation methods. As a result, model structures don't have enough seismic performance.

Performance-based and damage assessment of SFRP retrofitted multi-storey timber buildings

  • Vahedian, Abbas;Mahini, Seyed Saeed;Glencross-Grant, Rex
    • Structural Monitoring and Maintenance
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    • v.2 no.3
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    • pp.269-282
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    • 2015
  • Civil structures should be designed with the lowest cost and longest lifetime possible and without service failure. The efficient and sustainable use of materials in building design and construction has always been at the forefront for civil engineers and environmentalists. Timber is one of the best contenders for these purposes particularly in terms of aesthetics; fire protection; strength-to-weight ratio; acoustic properties and seismic resistance. In recent years, timber has been used in commercial and taller buildings due to these significant advantages. It should be noted that, since the launch of the modern building standards and codes, a number of different structural systems have been developed to stabilise steel or concrete multistorey buildings, however, structural analysis of high-rise and multi-storey timber frame buildings subjected to lateral loads has not yet been fully understood. Additionally, timber degradation can occur as a result of biological decay of the elements and overloading that can result in structural damage. In such structures, the deficient members and joints require strengthening in order to satisfy new code requirements; determine acceptable level of safety; and avoid brittle failure following earthquake actions. This paper investigates performance assessment and damage assessment of older multi-storey timber buildings. One approach is to retrofit the beams in order to increase the ductility of the frame. Experimental studies indicate that Sprayed Fibre Reinforced Polymer (SFRP) repairing/retrofitting not only updates the integrity of the joint, but also increases its strength; stiffness; and ductility in such a way that the joint remains elastic. Non-linear finite element analysis ('pushover') is carried out to study the behaviour of the structure subjected to simulated gravity and lateral loads. A new global index is re-assessed for damage assessment of the plain and SFRP-retrofitted frames using capacity curves obtained from pushover analysis. This study shows that the proposed method is suitable for structural damage assessment of aged timber buildings. Also SFRP retrofitting can potentially improve the performance and load carrying capacity of the structure.

Effect of Seismic Load on Residential RC Buildings under Construction Considering Construction Period (시공기간을 고려한 주거용 철근콘크리트 건물의 시공 중 지진하중 영향 분석)

  • Choi, Seong-Hyeon;Kim, Jea-Yo
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.35 no.4
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    • pp.235-242
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    • 2022
  • Compared with buildings that have already been constructed, buildings under construction may be more vulnerable to such natural disasters as earthquakes because the concrete strength is not yet sufficient. Currently, Korean design standards present minimum performance targets for each seismic grade of buildings, but the seismic load for design is based on a return period of 2400 years. However, because the construction period of the building is much shorter than the period of use of the building, the application of the earthquake return period of 2400 years to buildings under construction may be excessive. Therefore, in this study, a construction stage model of buildings with 5, 15, 25, and 60 floors was created to analyze earthquake loads during construction of residential reinforced concrete (RC) buildings. The structural stability was confirmed by applying reduced seismic loads according to the return period. As a result, the structural stability was checked for an earthquake of the return period selected according to the construction period, and the earthquake return period that can secure structural safety according to the size of the building was confirmed.

Design Considerations for Concrete High-Rise Buildings

  • Chung, Kwangryang;Park, Chulho;Kim, Dohun
    • International Journal of High-Rise Buildings
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    • v.5 no.3
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    • pp.187-193
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    • 2016
  • Busan's Haeundae Resort project, which is currently being constructed by POSCO E&C, comprises the 101-story Landmark Tower and two 85-story residential towers. Presently, foundation and basement construction is complete, with a final completion date set for 2019. Considerations about the construction and design of the three reinforced concrete high-rise buildings will be discussed in this paper.

How to reduce short column effects in buildings with reinforced concrete infill walls on basement floors

  • Bikce, Murat
    • Structural Engineering and Mechanics
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    • v.38 no.2
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    • pp.249-259
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    • 2011
  • Band windows are commonly used in reinforced concrete structures for the purpose of ventilation and lighting. These applications shorten the lengths of the columns and, consequently, they are subject to higher shear forces as compared with those of hollow frames. Such short columns may cause some damages during earthquakes. Hence, these effects of short columns should be minimized by choosing the dimensions of the band windows properly in order to prevent serious damages in the structure. This can be achieved by taking into account the parameters that are crucial in causing short column effect. Hence, in this study, the effects of those parameters such as the widths and heights of the band windows, the number of bays and storeys within the frame, and the heights of storeys are examined. The effects of the parameters are analyzed using time history analysis. One of the important results of these analyses, is that, the widths of the band windows should be less than 60% of the clear span between the columns, whereas, their heights should be greater than 35% of the clear storey height in order to decrease the short column effects substantially during the design of the reinforced concrete structures.

Incremental dynamic analyses of concrete buildings reinforced with shape memory alloy

  • Mirtaheri, Masoud;Amini, Mehrshad;Khorshidi, Hossein
    • Steel and Composite Structures
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    • v.23 no.1
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    • pp.95-105
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    • 2017
  • The use of superelastic shape memory alloys (SMAs) as reinforcements in concrete structures is gradually gaining interest among researchers. Because of different mechanical properties of SMAs compared to the regular steel bars, the use of SMAs as reinforcement in the concrete may change the response of structures under seismic loads. In this study, the effect of SMAs as reinforcement in concrete structures is analytically investigated for 3-, 6- and 8-story reinforced concrete (RC) buildings. For each concrete building, three different reinforcement details are considered: (1) steel reinforcement (Steel) only, (2) SMA bar used in the plastic hinge region of the beams and steel bar in other regions (Steel-SMA), and (3), beams fully reinforced with SMA bar (SMA) and steel bar in other regions. For each case, columns are reinforced with steel bar. Incremental Dynamic Analyses (IDA) are performed using ten different ground motion records to determine the seismic performance of Steel, Steel-SMA and SMA RC buildings. Then fragility curves for each type of RC building by using IDA results for IO, LS and CP performance levels are calculated. Results obtained from the analyses indicate that 3-story frames have approximately the same spectral acceleration corresponding with failure of frames, but in the cases of 6 and 8-story frames, the spectral acceleration is higher in frames equipped with steel reinforcements. Furthermore, the probability of fragility in all frames increases by the building height for all performance levels. Finally, economic evaluation of the three systems are compared.