{"title":"Evaluation of seismic performance of rotational-friction slip dampers in near-field and far-filed earthquakes","authors":"Sahar Borhan, H. Tajammolian, Mehdi Yazdian","doi":"10.12989/EAS.2021.21.2.147","DOIUrl":"https://doi.org/10.12989/EAS.2021.21.2.147","url":null,"abstract":"In this study, the performance of rotational-friction slip dampers in steel structures with different heights is investigated by the use of fragility curves. The use of dampers is one of the methods for vibration control of structures by simultaneously increasing both the structural stiffness and damping. Rotational-friction slip dampers are among the passive control devices that dampen the earthquake energy through their stable cyclic behavior. To study the performance of these devices in steel structures, 3, 6 and 9-story steel moment frame structures are designed, and the mentioned dampers are attached to the structure by Chevron braces. To account for the earthquake uncertainty, with the aid of incremental dynamic analysis (IDA), the damper-equipped structure is subjected to both near-field and far-field ground motion records. The acceleration and drift engineering demand parameters are selected as the functions to quantify the damage states, and the design, modeling and material properties uncertainties are considered in accordance with FEMA P-695. Evaluation of statistical results and comparison of the fragility curves, shows that the probability of failure at different damage states decreases when the dampers are added to the structure. This decrease is more remarkable in low-rise structures and near-fault ground motions.","PeriodicalId":49080,"journal":{"name":"Earthquakes and Structures","volume":"21 1","pages":"147"},"PeriodicalIF":1.5,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48278782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Huang Difang, Han Xiaolei, Qiao Shengfang, Ji Jing, Jidong Cui
{"title":"Component deformation-based collapse evaluation of RC frameunder different collapse criteria","authors":"Huang Difang, Han Xiaolei, Qiao Shengfang, Ji Jing, Jidong Cui","doi":"10.12989/EAS.2021.21.2.113","DOIUrl":"https://doi.org/10.12989/EAS.2021.21.2.113","url":null,"abstract":"Developments in performance-based earthquake engineering have emphasized the importance of evaluation of structural collapse resistance. Several collapse criteria were proposed to define structural collapse in various perspective. In this paper, collapse resistant capacity of ductile reinforced concrete (RC) frame was evaluated using different collapse criteria. Since most of the criteria focus on overall structural response, a component deformation-based method was adopted to describe the damage in component level. Incremental dynamic analysis (IDA) of a 6-story ductile RC frame conforms to current codes was conducted in OpenSEES. The collapse resistant capacity under different collapse criteria was compared. Moreover, relationship between overall structural response and the distribution of damaged components were discussed through the component deformation-based method. It was indicated that the story of maximum inter-story drift ratio is neither consistent with the one which is most seriously damaged nor with the story of maximum residual inter-story drift ratio. Furthermore, the component deformation-based method can depict structural damaged state and formation of collapse mechanism more reasonably. The analysis result evidences that structure conforms to current code have the good ductility and hardly reaches physical collapse under rare earthquake, however, the structure is more likely to be demolished due to unacceptable residual deformation.","PeriodicalId":49080,"journal":{"name":"Earthquakes and Structures","volume":"21 1","pages":"113"},"PeriodicalIF":1.5,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47143705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Experimental and numerical study on seismic behavior of a self-centering railway bridge pier","authors":"X. Xia, Suiwen Wu, X. Wei, Chiyu Jiao, Xingchong Chen","doi":"10.12989/EAS.2021.21.2.173","DOIUrl":"https://doi.org/10.12989/EAS.2021.21.2.173","url":null,"abstract":"This study mainly focuses on experimental and numerical investigation of the isolation mechanism and seismic performance of a self-centering railway bridge pier. To begin, a 1/25 scale typical self-centering railway pier model was designed and constructed, which consisted of a gravity pier, a spread foundation and a pedestal. The gravity pier was rigidly connected to the spread foundation, which was then directly seated at the top of the pile cap to allow the uplift of the pier during strong earthquakes. The model was tested in a pseudo-static manner under constant axial load and cyclic lateral load to characterize its seismic performance. It was found that the lateral load, the bending moment at the pier bottom, and the width of compression zone at the bottom of pier remained essentially constant when the uplift reached a certain extent. The hysteretic curves were in inverse 'Z' shape with narrow loops indicating good self-centering effect but poor energy dissipation. This means that the lateral force-displacement relationship of this type of piers can be simplified as an elasto-plastic curve and they should be used along with additional energy-dissipation devices. Upon the test results, a two-spring model was proposed and developed in the OpenSees platform to represent the test model, which was analyzed using the test load history. The results indicate that the two-spring model can simulate the pseudo-static test with high precision. This modeling technique hence can be employed to analyze seismic response of this type of bridge piers.","PeriodicalId":49080,"journal":{"name":"Earthquakes and Structures","volume":"21 1","pages":"173-183"},"PeriodicalIF":1.5,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42706502","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nie Wei, L. Shuxian, Luo Shasha, Li Shaodong, B. Chun, Y. Hang
{"title":"Seismic performance analysis of rocking wall TMDs structurebased on shaking table test","authors":"Nie Wei, L. Shuxian, Luo Shasha, Li Shaodong, B. Chun, Y. Hang","doi":"10.12989/EAS.2021.21.1.023","DOIUrl":"https://doi.org/10.12989/EAS.2021.21.1.023","url":null,"abstract":"","PeriodicalId":49080,"journal":{"name":"Earthquakes and Structures","volume":"21 1","pages":"23"},"PeriodicalIF":1.5,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42538250","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Estimation of inter-story drifts at onset of damage statesfor RC high-rise buildings","authors":"J. Pejovic, N. Serdar","doi":"10.12989/EAS.2021.21.1.063","DOIUrl":"https://doi.org/10.12989/EAS.2021.21.1.063","url":null,"abstract":"In this paper, a detailed probabilistic seismic damage analysis of RC high-rise buildings was performed and as a result, the damage states (DSs) and appropriate performance levels (PLs) were defined in a quantitative manner. DSs were quantified using inter-story drift, where the drifts were determined at the onset of each DS. The analysis was performed on three RC high-rise buildings: 20-story, 30-story and 40-story with core wall structural system. Probabilistic seismic damage analysis was performed for 60 earthquake records, recorded on rock and stiff soil, and scaled to two intensity levels associated with probability of exceedance, 10 % in 50 years - 475-year return period (10%/50) and probability of exceedance, 2 % in 50 years - 2475-year return period (2%/50). In addition to these analyses for estimation the damage index, nonlinear static pushover analyses (NSPAs) were performed using different modal combination patterns. Large deviations among the pushover curves for individual considered modal combination patterns were observed. In order to adequately select the parameters for calculating damage index, an analysis of drifts and shear forces for individual modal combination patterns was performed. The functional dependencies between inter-story drifts and damage index were derived using the regression analysis. Based on the derived dependencies, the values of inter-story drifts at the onset of considered DSs for high-rise buildings were proposed.","PeriodicalId":49080,"journal":{"name":"Earthquakes and Structures","volume":"21 1","pages":"63"},"PeriodicalIF":1.5,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41754460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"An energy-based approach to determine the yield force coefficient of RC frame structures","authors":"Onur Merter, Taner Ucar","doi":"10.12989/EAS.2021.21.1.037","DOIUrl":"https://doi.org/10.12989/EAS.2021.21.1.037","url":null,"abstract":"This paper proposes an energy-based approach for estimating the yield force coefficient of reinforced concrete (RC) frame structures. The procedure is mainly based on the energy balance concept and it considers the nonlinear behavior of structures. First, an energy modification factor is defined to consistently obtain the total energy of the equivalent elastic-plastic single-degree-of-freedom (SDOF) system. Then, plastic energy is formulated as functions of the several structural parameters such as the natural frequency, the strength reduction factor and the yield displacement. Consequently, the plastic energy formulation is derived for multi-degree-of-freedom (MDOF) systems and the yield force coefficient is determined by equating the plastic energy relation to the work needed to push the structure from the yield displacement up to the maximum displacement monotonically. The validity of the energy-based approach is assessed on several RC frame structures by means of nonlinear static pushover analysis considering both material and geometrical nonlinearity. A modification factor is proposed for the yield force coefficient to consider the strain-hardening effects in lateral forces. Moreover, the modified energy-based yield force coefficients are correlated to practical design by using the ductility ratios imposed by Turky Building Earthquake Code and a quite good agreement is observed.","PeriodicalId":49080,"journal":{"name":"Earthquakes and Structures","volume":"21 1","pages":"37"},"PeriodicalIF":1.5,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41774301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Study on seismic response characteristics of full light-weight concrete prefabricated utility tunnels","authors":"Yanmin Yang, Ran Xu, Yongqing Li, Zi-li Li","doi":"10.12989/EAS.2021.21.1.051","DOIUrl":"https://doi.org/10.12989/EAS.2021.21.1.051","url":null,"abstract":"In order to evaluate the seismic response characteristics of full light-weight concrete prefabricated utility tunnels, four prefabricated utility tunnels were conducted for test with different variables. Under unidirectional seismic excitation, the seismic response characteristics were analyzed by shaking table tests. And the corresponding numerical analysis models were proposed with ABAQUS. Based on the comparison between the simulation results and the experimental data, the influences of the parameters that full light-weight concrete, haunch heights, and reinforcement ratio on seismic response of prefabricated utility tunnels were systematically studied. The results indicated that the value of the peak acceleration, acceleration amplification factor, and peak displacement were reduced significantly with full light-weight concrete, which could decrease the seismic response of prefabricated utility tunnels. When the haunch heights and reinforcement ratio were properly increased, the seismic performance of prefabricated utility tunnels could be improved slightly. In addition, the peak displacement of full light-weight concrete prefabricated utility tunnels could meet the requirements, and there was no obvious damage until the end of test. The simulation results were in good agreement with the experimental data, and the seismic response characteristics were consistent. The results of this paper could provide a technical basis for the promotion and application for full light-weight concrete prefabricated utility tunnels.","PeriodicalId":49080,"journal":{"name":"Earthquakes and Structures","volume":"21 1","pages":"051"},"PeriodicalIF":1.5,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43534756","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Torsional sensitivity criteria in seismic codes","authors":"A. Athanatopoulou, G. Manoukas","doi":"10.12989/EAS.2021.21.1.001","DOIUrl":"https://doi.org/10.12989/EAS.2021.21.1.001","url":null,"abstract":"","PeriodicalId":49080,"journal":{"name":"Earthquakes and Structures","volume":"21 1","pages":"1"},"PeriodicalIF":1.5,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48651127","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A multi-hazard-based design approach for LRB isolation systemagainst explosion and earthquake","authors":"Hamed Dadkhaha, M. Mohebbi","doi":"10.12989/EAS.2021.21.1.095","DOIUrl":"https://doi.org/10.12989/EAS.2021.21.1.095","url":null,"abstract":"Base isolation system is originally known as one of the most efficient earthquake-resistance control systems. Isolated strategic structures may also experience terrorist attacks during their lifetime. In this paper, a design method is proposed for lead rubber bearing (LRB) isolation system under multi-hazard of explosion and seismic. This method is based on transforming the design problem into an optimization problem. The seismic response of structure has been defined as objective function while the constraints have been applied on its blast response. To validate the effectiveness of the proposed design method, LRB is designed for controlling a four-story steel moment-resisting building. For comparison objectives, this control system has been also designed under seismic hazard without paying attention to its blast performance. The results show that the earthquake-based optimally designed LRB has effective performance under seismic hazard whereas its blast performance is not as good as its seismic performance. Therefore, this control system cannot be considered as a well-designed control system for multi-hazard. The multi-hazard-based optimally designed LRB shows excellent performance under both blast and seismic loadings, so the proposed design method can be introduced as an effective design approach for LRB under multi-hazard of explosion and seismic.","PeriodicalId":49080,"journal":{"name":"Earthquakes and Structures","volume":"21 1","pages":"95"},"PeriodicalIF":1.5,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46361735","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Post-earthquake fire resistance of tall steel concentrically braced frames","authors":"Rasul Kaffasha, A. Karamodin","doi":"10.12989/EAS.2021.21.1.011","DOIUrl":"https://doi.org/10.12989/EAS.2021.21.1.011","url":null,"abstract":"The fire which occurs after an earthquake causes great problems for buildings situated in moderate to high seismic regions. In this article in order to have an understanding regarding the impacts of post-earthquake fire on the structures, implementing the finite element method, the behaviour of tall steel concentrically braced frames when subjected to this type of loading was investigated. The simulation under seismic loading was done using the nonlinear time history analysis. Assuming the post-earthquake situation of the structure as the initial condition, the mechanical-thermal analysis was applied using the temperature-time diagram on the exposed elements. The analysis results showed that regardless of the earthquake record and fire scenarios for the tall steel concentrically braced frames, the fire resistance duration was short and the impacts of the previous earthquake on the structure fire resistance were not considerable.","PeriodicalId":49080,"journal":{"name":"Earthquakes and Structures","volume":"21 1","pages":"11"},"PeriodicalIF":1.5,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41495154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}