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Overview of Performance-Based Seismic Design of Building Structures in China

  • Li, Guo-Qiang;Xu, Yan-Bin;Sun, Fei-Fei
    • International Journal of High-Rise Buildings
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    • v.1 no.3
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    • pp.169-179
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    • 2012
  • The development history, the current situation and the future of the performance-based seismic design of building structures in China are presented in this paper. Firstly, the evolution of performance-based seismic design of building structures specified in the Chinese codes for seismic design of buildings of the edition 1974, 1978, 1989, 2001 and 2010 are introduced and compared. Secondly, in two parts, this paper details the provisions of performance-based seismic design in different Chinese codes. The first part is about the "Code for Seismic Design of Buildings" (GB50011) (edition 1989, 2001 and 2010) and "Technical Specification for Concrete Structures of Tall Building", which presents the concepts and methods of performance-based seismic design adopted in Chinese codes; The second part is about "Management Provisions for Seismic Design of Outof-codes High-rise Building Structures" and "Guidelines for Seismic Design of Out-of-codes High-rise Building Structures", which concludes the performance-based seismic design requirements for high-rise building structures over the relevant codes in China. Finally, according to those mentioned above, this paper pointed out the imperfections of current performance-based seismic design in China and proposed the possible direction for further improvement.

Effect of design spectral shape on inelastic response of RC frames subjected to spectrum matched ground motions

  • Ucar, Taner;Merter, Onur
    • Structural Engineering and Mechanics
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    • v.69 no.3
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    • pp.293-306
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    • 2019
  • In current seismic design codes, various elastic design acceleration spectra are defined considering different seismological and soil characteristics and are widely used tool for calculation of seismic loads acting on structures. Response spectrum analyses directly use the elastic design acceleration spectra whereas time history analyses use acceleration records of earthquakes whose acceleration spectra fit the design spectra of seismic codes. Due to the fact that obtaining coherent structural response quantities with the seismic design code considerations is a desired circumstance in dynamic analyses, the response spectra of earthquake records used in time history analyses had better fit to the design acceleration spectra of seismic codes. This paper evaluates structural response distributions of multi-story reinforced concrete frames obtained from nonlinear time history analyses which are performed by using the scaled earthquake records compatible with various elastic design spectra. Time domain scaling procedure is used while processing the response spectrum of real accelerograms to fit the design acceleration spectra. The elastic acceleration design spectra of Turkish Seismic Design Code 2007, Uniform Building Code 1997 and Eurocode 8 are considered as target spectra in the scaling procedure. Soil classes in different seismic codes are appropriately matched up with each other according to $V_{S30}$ values. The maximum roof displacements and the total base shears of considered frame structures are determined from nonlinear time history analyses using the scaled earthquake records and the results are presented by graphs and tables. Coherent structural response quantities reflecting the influence of elastic design spectra of various seismic codes are obtained.

Development of Performance-Based Seismic Design in U.S.A (미국의 차세대 내진설계 개념의 발전 동향)

  • 이한선
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 1998.10a
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    • pp.44-53
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    • 1998
  • The objective of this paper is to review the current state of practice in the seismic codes in the U.S.A. and to investigate its trend in the development of performance-based seismic design for the 21st century. This study is supposed to be eventually utilized as a basis material to establish the new seismic code appropriate in our country having the moderate seismic hazard. To do this, the history of the seismic codes in U.S.A. is first briefly investigated and then the critical review on the recent codes is made. Finally, the conceptual framework of the performance-based seismic design and the development of the guideline documents to implement this to the rehabilitation of existing building structures are introduced.

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the height-wise distribution of lateral seismic forces considering the contribution of the higher modes (고차모드 효과를 고려한 층 지진하중 분배)

  • 황준호
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 1999.10a
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    • pp.273-280
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    • 1999
  • The base shear and the veritcal distribution of shears along the height of a building are two fundamental measures that define the design seismic load. But the method specified in Korean building code does not give an appropriate distribution for buildings of tall or longer period because it roughly account for the contributions of the higher modes. several methods to give a better distribution of seismic forces have been proposed. But they have not been introduced into the seismic codes yet probably because they cannot solve all the above-mentioned problems. This paper deals with the distribution of lateral seismic forces along the height of a building to account for the contribution of the higher modes. After reviewing some existing distributions in seismic codes and literatures moment-resisting frames with various stories were studied by modal analysis for a wide range of fundamental period and the stiffness ratio of the buiding. As a result of the analysis a new expression for the distribution of seismic forces is proposed and compared with those of some codes and dynamic analysis.

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Review of Code Provisions on Seismic Design of Fire Protection System (소방설비 내진설계에 관한 각국 기준 비교 연구)

  • Lee, Hyun-Jin;Shin, Yi-Chul;Lee, Jae-Young;Seo, Dong-Goo;Han, Byung-Chan;Kim, Jae-Hwan;Kwon, Young-Jin
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2008.04a
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    • pp.238-241
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    • 2008
  • In this paper, provisions related with the seismic design and equipments of fire protection system are being considered. The provisions from various international codes on seismic design fire protection system were reviewed. The codes, reviewed are, Japanese code, NFPA guideline and Korean code. It is noted that all the codes excepted to korean code consider earthquake effect to evaluate seismic forces and behaviors. But, korean provision are not covered in seismic response in all. A brief description on limitations in korean code is also presented.

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Comparison of the seismic performance of existing RC buildings designed to different codes

  • Zeris, Christos A.;Repapis, Constantinos C.
    • Earthquakes and Structures
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    • v.14 no.6
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    • pp.505-523
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    • 2018
  • Static pushover analyses of typical existing reinforced concrete frames, designed according to the previous generations of design codes in Greece, have established these structures' inelastic characteristics, namely overstrength, global ductility capacity and available behaviour factor q, under planar response. These were compared with the corresponding demands at the collapse limit state target performance point. The building stock considered accounted for the typical variability, among different generations of constructed buildings in Greece, in the form, the seismic design code in effect and the material characteristics. These static pushover analyses are extended, in the present study, in the time history domain. Consequently, the static analysis predictions are compared with Incremental Dynamic Analysis results herein, using a large number of spectrum compatible recorded base excitations of recent destructive earthquakes in Greece and abroad, following, for comparison, similar conventional limiting failure criteria as before. It is shown that the buildings constructed in the 70s exhibit the least desirable behaviour, followed by the buildings constructed in the 60s. As the seismic codes evolved, there is a notable improvement for buildings of the 80s, when the seismic code introduced end member confinement and the requirement for a joint capacity criterion. Finally, buildings of the 90s, designed to modern codes exhibit an exceptionally good performance, as expected by the compliance of this code to currently enforced seismic provisions worldwide.

Quantifying the seismic resilience of two tall buildings designed using Chinese and US Codes

  • Tian, Yuan;Lu, Xiao;Lu, Xinzheng;Li, Mengke;Guan, Hong
    • Earthquakes and Structures
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    • v.11 no.6
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    • pp.925-942
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    • 2016
  • With ongoing development of earthquake engineering research and the lessons learnt from a series of strong earthquakes, the seismic design concept of "resilience" has received much attention. Resilience describes the capability of a structure or a city to recover rapidly after earthquakes or other disasters. As one of the main features of urban constructions, tall buildings have greater impact on the sustainability and resilience of major cities. Therefore, it is important and timely to quantify their seismic resilience. In this work, a quantitative comparison of the seismic resilience of two tall buildings designed according to the Chinese and US seismic design codes was conducted. The prototype building, originally designed according to the US code as part of the Tall Building Initiative (TBI) Project, was redesigned in this work according to the Chinese codes under the same design conditions. Two refined nonlinear finite element (FE) models were established for both cases and their seismic responses were evaluated at different earthquake intensities, including the service level earthquake (SLE), the design-based earthquake (DBE) and the maximum considered earthquake (MCE). In addition, the collapse fragility functions of these two building models were established through incremental dynamic analysis (IDA). Based on the numerical results, the seismic resilience of both models was quantified and compared using the new-generation seismic performance assessment method proposed by FEMA P-58. The outcomes of this study indicate that the seismic resilience of the building according to the Chinese design is slightly better than that according to the US design. The conclusions drawn from this research are expected to guide further in-depth studies on improving the seismic resilience of tall buildings.

The comparison of sectional damages in reinforced-concrete structures and seismic parameters on regional Basis; a case study from western Türkiye (Aegean Region)

  • Ercan Isik;Hakan Ulutas;Aydin Buyuksarac
    • Earthquakes and Structures
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    • v.24 no.1
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    • pp.37-51
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    • 2023
  • Türkiye has made significant changes and updates in both seismic risk maps and design codes over time, as have other countries with high seismic risk. In this study, the last two seismic design codes and risk maps were compared for the Aegean Region (Western Türkiye) where the earthquake risk has once again emerged with the 2020 Izmir Earthquake (Mw=6.9). In this study, information about the seismicity of the Aegean Region was given. The seismic parameters for all provinces in the region were compared with the last two earthquake risk maps. The spectral acceleration coefficients of all provinces have increased and differentiated with the current seismic hazard map as a result of the design spectra used on a regional basis have been replaced by the geographical location-specific design spectra. In addition, section damage limits were obtained for all provinces within the scope of the last two seismic design codes. Structural analyses for a sample reinforced-concrete building were made separately for each province using pushover analysis. The deformations in the cross-sections were compared with the limit states corresponding to the damage levels specified in the last two seismic design codes for the region. Target displacement requests for all provinces have decreased with the current code. The differentiation of geographical location-specific design spectra both in the last two seismic design code and between provinces has caused changes in section damages and building performance levels. The main aim of this study is to obtain and compare both seismic and structural analysis results for all provinces in the Aegean Region (Western Türkiye).

A Study on Optimum Distribution of Story Shear Force Coefficient for Seismic Design of Multi-story Structure

  • Oh, Sang Hoon;Jeon, Jongsoo
    • International Journal of High-Rise Buildings
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    • v.3 no.2
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    • pp.121-145
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    • 2014
  • The story shear force distributions of most seismic design codes generally reflect the influences of higher vibration modes based on the elastic deformations of structures. However, as the seismic design allows for the plastic behavior of a structure, the story shear force distribution shall be effective after it is yielded due to earthquake excitation. Hence this study conducted numerical analyses on the story shear force distributions of most seismic design codes to find out the characteristics of how a structure is damaged between stories. Analysis results show that the more forces are distributed onto high stories, the lower its concentration is and the more energy is absorbed. From the results, this study proposes the optimum story shear force distribution and its calculation formula that make the damages uniformly distributed onto whole stories. Consequently, the story damage distribution from the optimum calculation formula was considerably more stable than existing seismic design codes.

Seismic force evaluation of RC shear wall buildings as per international codes

  • Jayalekshmi, B.R.;Chinmayi, H.K.
    • Earthquakes and Structures
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    • v.10 no.1
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    • pp.191-209
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    • 2016
  • Seismic codes are the best available guidance on how structures should be designed and constructed to ensure adequate resistance to seismic forces during earthquakes. Seismic provisions of Indian standard code, International building code and European code are applied for buildings with ordinary moment resisting frames and reinforced shear walls at various locations considering the effect of site soil conditions. The study investigates the differences in spectral acceleration coefficient ($S_a/g$), base shear and storey shear obtained following the seismic provisions in different codes in the analysis of these buildings. Study shows that the provision of shear walls at core in low rise buildings and at all the four corners in high rise buildings gives the least value of base shear.