• Title/Summary/Keyword: seismic design

Search Result 2,996, Processing Time 0.027 seconds

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
    • /
    • v.69 no.3
    • /
    • pp.293-306
    • /
    • 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.

The inspection and seismic design method of electrical facility instated in the building (건축물에 시설되는 수변전설비 내진설계 및 검사 방법에 관한 연구)

  • Kim, Gi-Hyun;Lee, Sang-Ick;Kang, Min-Hee;Bae, Suk-Myong
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
    • /
    • 2009.05a
    • /
    • pp.332-335
    • /
    • 2009
  • Incase of not considered seismic design at transformer vault which is made of many informant electrical facility, facility is damaged, electrical fire breaks out and second damage is able to break out at generating earthquake. But seismic design yet is not applied to at transformer vault in the country. Regard to seismic design method of electrical facility installed in the building internal, we present the seismic design of electrical facility using "Building construction design standard" in internal and "Manual of seismic design and construction for Building Electrical facility" in japan. This paper will be used detail seismic design of pipe and facility. reliability inspection plan for seismic design and construction of electrical facility

  • PDF

Verification of diaphragm seismic design factors for precast concrete office buildings

  • Zhang, Dichuan;Fleischman, Robert B.;Lee, Deuckhang
    • Earthquakes and Structures
    • /
    • v.20 no.1
    • /
    • pp.13-27
    • /
    • 2021
  • A new seismic design methodology has been developed for precast concrete diaphragms. Seismic design factors were used to be applied on top of diaphragm seismic design forces in the current code. These factors, established through extensive parametric studies, align diaphragm design strengths with different seismic performance targets. A simplified evaluation structure with a single-bay plan was used in the parametric studies. This simplified evaluation structure is reasonable and cost-effective as it can comprehensively cover structural geometries and design parameters. However, further verification and investigation are required to apply these design factors to prototype structures with realistic layouts. This paper presents diaphragm design of several precast concrete office buildings using the new design methodology. The applicability of the design factor to the office building was evaluated and verified through nonlinear time history analyses. The seismic behavior and performance of the diaphragm were investigated for the precast concrete office buildings. It was found that the design factor established for the new design methodology is applicable to the realistic precast concrete office buildings.

Damage controlled optimum seismic design of reinforced concrete framed structures

  • Gharehbaghi, Sadjad
    • Structural Engineering and Mechanics
    • /
    • v.65 no.1
    • /
    • pp.53-68
    • /
    • 2018
  • In this paper, an innovative procedure is proposed for the seismic design of reinforced concrete frame structures. The main contribution of the proposed procedure is to minimize the construction cost, considering the uniform damage distribution over the height of structure due to earthquake excitations. As such, this procedure is structured in the framework of an optimization problem, and the initial construction cost is chosen as the objective function. The aim of uniform damage distribution is reached through a design constraint in the optimization problem. Since this aim requires defining allowable degree of damage, a damage pattern based on the concept of global collapse mechanism is presented. To show the efficiency of the proposed procedure, the uniform damage-based optimum seismic design is compared with two other seismic design procedures, which are the strength-based optimum seismic design and the damage-based optimum seismic design. By using the three different seismic design methods, three reinforced concrete frames including six-, nine-, and twelve-story with three bays are designed optimally under a same artificial earthquake. Then, to show the effects of the uniform damage distribution, all three optimized frames are used for seismic damage analysis under a suite of earthquake records. The results show that the uniform damage-based optimum seismic design method renders a design that will suffer less damage under severe earthquakes.

Review and Proposal for Seismic Safety Assessment of Nuclear Power Plants against Beyond Design Basis Earthquake (설계초과 지진에 대한 원전 지진안전성 평가기술 고찰 및 제언)

  • Choi, In-Kil
    • Transactions of the Korean Society of Pressure Vessels and Piping
    • /
    • v.13 no.1
    • /
    • pp.1-15
    • /
    • 2017
  • After Kyeongju earthquake occurred in September 12, 2016, the seismic safety of nuclear power plants became important issue in our country. The seismic safety of nuclear power plant against beyond design basis earthquake became very important to secure the public safety. In this paper, the current status of the seismic safety assessment methodology is reviewed and some aspects for the reliability improvement of the seismic safety assessment results are proposed. Seismic margin analysis and probabilistic seismic safety assessment have been used for the seismic safety evaluation of a nuclear power pant. The basic procedure and the related issues and proposals for the probabilistic seismic safety assessment are investigated.

Optimum Design of Retaining Wall with Seismic Constraints (내진제약조건(耐震制約條件)을 갖는 옹벽(擁壁)의 최적설계(最適設計))

  • Kim, Kee-Dae
    • Journal of the Korean Society of Industry Convergence
    • /
    • v.6 no.2
    • /
    • pp.95-102
    • /
    • 2003
  • In this paper, optimum design is considered over the retaining wall with seismic constraints. The sequential linear programming method(SLP) is used as a rational approach to this optimum design. To make a comparison between the seismic design and the normal design, retaining wall with 4~7m height were adopted. It is shown that the seismic design is more expensive (over 30%) than the normal design for the construction cost.

  • PDF

Seismic Design of Soil-Reinforced Segmental Retaining Walls (블록식 보강토 옹벽의 내진설계)

  • 유충식
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 1999.11c
    • /
    • pp.69-83
    • /
    • 1999
  • Soil-reinforced segmental retaining walls(SRW) have been proven to be high earthquake-resistant structure during recent earthquakes in United States and Japan. The mechanicals behavior of the SRWs under seismic loading, however, has not been fully understood. Although the seismic design issues for the civil engineering structures have gained much attention in Korea due to the increase in frequency of earthquake occurrence, the seismic design for the SRWs has not been being implemented. This study has been undertaken with the aim of developing a more rational seismic design/analysis method for soil-reinforced segmental retaining walls. This paper present fundamentals of current seismic design/analysis method and the results of a comparative study between NCMA and FHWA design guidelines, Practical implications of the findings from this study are discussed in great detail.

  • PDF

Generation of Seismic Environment and Design Code Compatible Representative Earthquake Motion (지진환경과 설계기준과 호환하는 대표 입력 지진파의 생성)

  • Jeong, Chang-Gyun;Park, Du-Hee
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2010.03a
    • /
    • pp.771-776
    • /
    • 2010
  • Since the importance of seismic design is greater, dynamic analysis is more widely using than past. The input motion is one of the most important factors of dynamic analysis. However, in Korea input motions are selected from U.S. and Japan those are captured from large magnitude earthquakes without considering seismic environment or generated in frequency domain. In this research, the methodology for generating input motions those are considered seismic environment and design code is proposed. The seismic environment compatibility is considered by performing deaggregation and the design code compatibility is considered by time-domain artificial time history accelration generation method. The results shows that seismic environment and design code compatible input motions are successfully generated.

  • PDF

Capacity Design of RC Bridge Columns for Seismic Loading

  • Lee Jae Hoon;Ko Seong Hyun;Choi Jin Ho;Shin Sung Jin
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2004.11a
    • /
    • pp.591-594
    • /
    • 2004
  • Recently, a tendency for development of seismic approach of foreign countries is capacity design development. Capacity design is rational seismic design concept of capacity protection considering not only earthquake magnitude, but also behavior of structure. For that reason, the most bridge seismic design specifications contain capacity protection provisions explicitly or implicitly. The capacity protection is normally related with slenderness effect of the columns, force transfer in connections between columns and adjacent elements, and shear design of columns. It intends to prevent brittle failure of the structural components of bridges, so that the whole bridge system may show ductile behavior and failure during earthquake events. The objectives of this paper are to deduce needed provisions for the moderate seismicity regions such as Korea after studying current seismic design codes and to establish rational criteria provisions of seismic design for future revision of seismic design specifications.

  • PDF

Verification of diaphragm seismic design factors for precast concrete parking structures

  • Zhang, Dichuan;Fleischman, Robert
    • Structural Engineering and Mechanics
    • /
    • v.71 no.6
    • /
    • pp.643-656
    • /
    • 2019
  • A new seismic design methodology was proposed for precast concrete diaphragms. This methodology adopts seismic design factors applied on top of current diaphragm design forces. These factors are aimed to produce diaphragm design strengths aligned with different seismic performance targets. These factors were established through extensive parametric studies. These studies used a simple evaluation structure with a single-bay rectangular diaphragm. The simple evaluation structure is suitable for establishment of the design factors over comprehensive structural geometry and design parameters. However, the application of the design factors to prototype structures with realistic layouts requires further verification and investigation. This paper presents diaphragm design of several precast concrete parking structures using the new design methodology and verification of the design factor through nonlinear dynamic time history analyses. The seismic behavior and performance of the diaphragm were investigated for the precast concrete parking structures. It was found that the design factor established for the new design methodology is applicable to the realistic precast concrete parking structures.