@article { author = {Alipour, Mohammadreza and Khodaverdian, Alireza and Zafarani, Hamid and Rahimian, Mohammad}, title = {Physics-Based Earthquake Simulation for the Alborz Region to Evaluate Seismicity Parameters}, journal = {Bulletin of Earthquake Science and Engineering}, volume = {6}, number = {2}, pages = {1-14}, year = {2019}, publisher = {International Institute of Earthquake Engineering and Seismology}, issn = {2476-6097}, eissn = {2476-6100}, doi = {}, abstract = {The Iranian Plateau is characterized as one of the most seismic regions in the world, and the most populated cities are located near its active faults, indicating high possible seismic risk. Estimation of earthquake occurrence probabilities can play an important role in earthquake damage mitigation. In the present study, earthquake simulation technique, based on the boundary elements method, is used for the Alborz region in order to have more accurate estimates of earthquakes return periods and consider faults interaction. First of all, seismic parameters for the region are evaluated using the obtained synthetic catalog. In addition, the synthetic activity rates are also compared to independent past studies (e.g. paleoseismological investigation). The estimated return periods lie within the uncertainties of previous studies, showing robustness of the proposed model. As the next step, characteristic earthquake magnitude and its return period distribution are presented for all active faults in the study region. According to the synthetic catalog, earthquake occurrence probability for an individual fault is related to the time elapsed from the last earthquake while earthquakes occurrence tends to a random behavior if all active faults in the region are considered together. Given the long-term seismic catalog and determination of the last earthquakes for each fault, earthquakes occurrence probabilities are estimated for the next 10, 25, 50 and 100 years for all active faults. The more time elapse form the last earthquake, the more earthquake occurrence probabilities are estimated, confirming Reid’s theory and proving necessity of long-term simulation to have a better estimate of earthquakes occurrence probabilities.}, keywords = {Physics-Based Earthquake Simulation,Seismicity Parameters,Earthquakes Return Periods,Probabilities of Earthquakes Occurrence}, title_fa = {شبیه‌سازی سیکل‌های زلزله مبتنی بر فیزیک لغزش جهت ارزیابی پارامترهای لرزه‌ای در ناحیه البرز}, abstract_fa = {با توجه به قرارگیری اکثر مراکز جمعیتی البرز در محدوده گسل‌‌ها، مطالعه دقیق‌‌تر احتمال وقوع زلزله می‌تواند نقشی مهمی در کاهش خسارت‌های ناشی از زلزله داشته باشد. در همین راستا، با هدف برآورد دقیق‌‌تر دوره بازگشت زلزله‌های بزرگ در ناحیه البرز، شبیه‌‌سازی از وقوع زلزله­ها صورت‌گرفته و کاتالوگ لرز‌ه‌ای مصنوعی برای بازه زمانی400 هزار ساله ارائه شده است. با هدف صحت‌سنجی شبیه‌سازی صورت­گرفته، پارامترهای لرزه‌خیزی برای ناحیه البرز برآورد و با نتایج به‌دست‌آمده از شبیه‌سازی مقایسه شد. از سوی دیگر، کاتالوگ لرزه‌‌ای پیشنهادی با مطالعات قبلی دیرینه‌‌لرزه‌‌شناسی مورد ارزیابی قرار گرفت و سازگاری موارد فوق نشان از صحت مدل ارائه شده دارد. با در اختیار داشتن کاتالوگ لرزه­ای بلندمدت، بزرگای زلزله مشخصه و توزیع دوره بازگشت مرتبط با آن برای تمامی گسل‌‌های فعال البرز گزارش و بررسی آماری نشان‌دهنده‌ی رفتار متناسب با زمان دوره بازگشت زلزله‌هاست. همچنین، بررسی احتمال وقوع زلزله در گسل‌های فعال البرز برای دوره‌های زمانی مختلف نشان‌دهنده‌ی آن است که هر چه زمان بیشتری از وقوع آخرین رخداد گذشته باشد احتمال وقوع زلزله بیشتر خواهد بود؛ این موضوع تأییدکننده تئوری رید و ضرورت استفاده از شبیه‌‌سازی بلندمدت برای برآورد دقیق‌‌تر از احتمال وقوع زلزله است.}, keywords_fa = {شبیه سازی زلزله,کاتالوگ لرزه ای مصنوعی,احتمال وقوع زلزله,ناحیه البرز}, url = {http://www.bese.ir/article_240384.html}, eprint = {http://www.bese.ir/article_240384_2250fa7ca1b43203d4136e5b1538de06.pdf} } @article { author = {Rezaei, Mohammad Hadi and Khaji, Naser}, title = {Fault Modeling by a Specific Barrier Model Using a New Approach for Circular Cracks’ Arrangement}, journal = {Bulletin of Earthquake Science and Engineering}, volume = {6}, number = {2}, pages = {15-27}, year = {2019}, publisher = {International Institute of Earthquake Engineering and Seismology}, issn = {2476-6097}, eissn = {2476-6100}, doi = {}, abstract = {In order to develop a reliable fault simulation process, there are three crucial parameters which needs to be accurately introduced. The mentioned parameters are seismic source specifications, wave propagation path, and seismic site effects. Relationships of strong ground motion attenuation are important for seismic hazard analysis at a specific site. Attenuation relationships may be obtained using two different approaches depending upon the region under study. In the first approach which is appropriate for regions with abundant records of strong ground motion, the statistical model can be used for developing the attenuation relationships employing regression techniques. The common required data for developing attenuation relationships consist of magnitudes, source-to-site distances, and peak ground characteristics. For regions such as California, Japan, and Taiwan, with sufficient data, these methods are suitable and have been successfully developed. Obviously, the validity and accuracy of these methods strongly depend on data sufficiency, the type of regression technique, and the classification of data. On the other hand, for the regions of limited records of strong ground motion, the first approach may not be appropriate and the application of physical models, as the second approach, will be necessary for successful predicting. In this approach, limited records are basically employed for the physical model calibration. These models usually have been developed in the context of the random vibration theory and the stochastic modeling approach. Among various seismic source specifications, a more physically realistic source model is the specific barrier model (SBM). The SBM is known as one of the most complete, simple, and self-consistent statement of the faulting process which is applicable in both "near-fault" and "far-field" regions. Consequently, the SBM may provide consistent ground motion simulations over the entire necessary frequency range and for all distances of engineering interests. The SBM is specifically more suitable for regions with poor seismological data-base and/or ground motions from large earthquakes with large recurrence intervals. An essential part of the seismological model used in this method is the quantitative description of the far-field spectrum of seismic waves emitted from the seismic source. Since shear (S) wave is primarily the main factor of earthquake damages, the application of stochastic approach of the SBM has almost been focused on the far-field S wave spectrum, in which two corner frequencies of observed earthquake are represented. The ‘two-corner-frequency’ shows two considerable length-scales of an earthquake source: a length-scale that quantifies the overall size of the fault that ruptures (e.g., the length L of a strike-slip fault) and another length-scale that measures the size of the subevents. Associated with these length-scales are two corresponding time scales: (1) the overall duration of rupture, and (2) the rise time. The SBM has a few main source parameters which have been calibrated to earthquakes of different tectonic regions. The SBM may be considered as a general idealization of the faulting process of an earthquake. For example, the SBM originally is an aggregate of some circular cracks which take place on the fault plane. In initial version of the SBM, the size of all cracks was assumed to be equal; however, the random nature of earthquake phenomenon leads to considering some modifications on such an assumption. In the present paper, a new method of so-called geometry packing is introduced to locate circular cracks of different radii in the fault plane. Using different size of circles is expected to result in more realistic model of earthquake source. In this method, the mentioned circles are set next to each other with no intersections between them. In other words, the proposed method guarantees the existence of barriers between of circular cracks of random radii. The aspect ratio of length to width (𝐿𝑊⁄) as an important parameter which effects on the number and arrange of circular cracks, is usually being ignored by recent modifications of the SBM. In other words, the mentioned methods usually use equivalent circular fault by radius of 𝑅𝐶 and the same area as rectangular fault, instead of the rectangular one. In this study, by using the fault’s geometry as the basis of calculations, the aspect ratio of the fault plane may effect on the number and arrangement of circular cracks in the model. Also, this method has capability to set specific size of circles in specified location of the fault, which may become useful in more complex future models. Afterwards, by using the proposed method, source spectra of different faults are investigated.}, keywords = {Kinematic Methods,Fault Modeling,Specific barrier model,Seismic Source Spectrum,Packing Method}, title_fa = {مدل‌سازی گسلش با استفاده از یک مدل موانع ویژه با شیوه جدید چیدمان دایره‌های گسیختگی}, abstract_fa = {رسیدن به یک تخمین قابل‌اطمینان از حرکات زمین، ناشی از وقوع زلزله در یک ساختگاه مشخص، بدون داشتن شناخت صحیح از مکانیسم تولید امواج لرزه‌ای، عوامل ساختاری اثرگذار بر این امواج در مسیر انتشار، و شناخت شرایط فیزیکی و ویژگی‌های ساختاری محل ساخته‌شدن سازه‌ها میسر نخواهد بود. در این میان، مدل موانع ویژه که از مشهورترین روش­های سینماتیکی شبیه­سازی گسل زلزله می­باشد، گسل را به‌عنوان مجموعه‌ای از ترک­های دایره‌ای در نظر می‌گیرد. گسیختگی که به‌صورت افت تنش‌های موضعی در این ترک‌ها فرض می‌شود، عامل اصلی تولید امواج فرکانس بالا در این مدل است. یکی از ایرادات وارد بر این مدل، استفاده از دایره‌های یکسان است، که با خاصیت ذاتی زلزله مبنی بر تصادفی بودن این رخداد، فاصله چشمگیری دارد. از این‌رو، در این مطالعه سعی شده با پیشنهاد روش جدید چیدمان دایره­ها با اندازه­های متفاوت، که به‌عنوان گسیختگی­های عامل تولید امواج لرزه‌ای می‌باشند، طیف‌های چشمه تولید شده را هرچه بیشتر به واقعیت نزدیک سازد. در روش پیشنهادی، دایره‌های با اندازه­های متفاوت به‌صورت کاملاً تصادفی در گسل قرار می­گیرند، از مجموع طیف‌های تک‌تک دوایر گسیختگی، طیف چشمه لرزه­زا تولید می‌شود. در انتها، نتایج طیف‌های تولیدشده برای گسل‌های با ابعاد متفاوت با مقادیر مشابه از مدل کلاسیک اولیه مقایسه می­شوند.}, keywords_fa = {روش های سینماتیکی,مدل‌سازی گسل,مدل موانع ویژه,طیف چشمه زلزله,چیدمان دوایر با اندازه مختلف}, url = {http://www.bese.ir/article_240388.html}, eprint = {http://www.bese.ir/article_240388_c578f0c9405acaf88732303f00312134.pdf} } @article { author = {Darzi, Atefe and Zolfaghari, Mohammad R.}, title = {A Statistical Investigation on Regional Dependency of Strong Ground-Motions in Iran and California}, journal = {Bulletin of Earthquake Science and Engineering}, volume = {6}, number = {2}, pages = {29-51}, year = {2019}, publisher = {International Institute of Earthquake Engineering and Seismology}, issn = {2476-6097}, eissn = {2476-6100}, doi = {}, abstract = {Iran is one of the most seismically active regions in the world with many historical and instrumental recorded earthquakes. Despite such high seismicity, the number of strong ground motion records available for main tectonic regions in Iran is not sufficient for reliable regional-dependent ground motion prediction equations (GMPEs). Moreover, it is generally acknowledged that sparse sampling and poor distribution of data result in limited applicability of GMPEs with regard to source-to-site distance and magnitude ranges. In order to cope with the lack of data, supplementary earthquake ground motions (GM) recorded in certain regions of the world with similar tectonic regimes can be combined into one dataset. Therefore, we aimed to explore the possibility of combining Iran and California datasets through assessment of the regional dependency of strong GMs. For this purpose, the statistical technique known as Analysis of Variance (ANOVA) is applied to both large sets of strong GMs from Iran and California. Analysis of variance does not rely on deriving GMPEs which makes it a strong and reliable technique for understanding of regional differences. California dataset comprises of 5902 records obtained from 218 earthquakes which are extracted from NGA-West2 database. The Iranian database used in the present study was obtained from Iran Strong Motion Network (ISMN) in unprocessed format. Data are processed using modified wavelet de-noising approach by which large numbers of noisy acceleration records that are usually discarded from datasets, can be corrected. The database comprises of 1943 pairs of horizontal acceleration time series obtained from 426 earthquakes with moment magnitudes ranging from 4.5 to 7.4 and distances up to 200 km. As source-to-site distance measure, closest distance to the fault rupture plane (denoted as Rrup) is computed for all records. Due to paucity of normal-faulting earthquakes in Iran, we excluded such events from our database.The large number of strong motion datasets from both regions available in present research enables us to perform the analysis of variance technique to many intervals with overlapping data from both regions. Consequently, more reliable results can be concluded compared to previous researches. We applied ANOVA to 5%-damped horizontal component of elastic response spectral acceleration at six different vibration periods (0.01, 0.1, 0.3, 0.5, 1, 2 and 5 seconds) and at intervals of to 5 km and 0.2 Mw. In order to combine two horizontal components, a single period-independent rotation measure (GMRotI50) is used.To provide more reliable results, site response effect on GM amplitudes is reduced using averaged horizontal-to-vertical spectral ratio (HVSR) for stations grouped by Iranian building design code based on time-averaged shear-wave velocity in the top 30 m ( VS30). For stations with unknown VS30 values, the VS30-prediction equation proposed by Darzi et al. (2019) is applied to Iranian strong-motion stations having fundamental frequency greater than 1 Hz. Note that due to small number of stations in class IV, they are combined with class III.This study first investigates the possibility of classifying the Iranian database into three tectonic regions of Northern Iran, East-Central Iran and Zagros. The ANOVA technique is applied to Mw-Rrup intervals with sufficient data from these regions two by two; however, the results did not show any strong regional-dependency, indicating that the nation-wide data could be considered as a single dataset. Then, the regional differences between GM amplitudes from Iran and California are evaluated using ANOVA technique. High evidence of regional dependency was revealed in some magnitude and distance ranges, supporting regional classification of dataset to prevent biased predictions. Based on these analyses, there is little evidence of regional difference for reverse-faulting events except for Mw = 5.8-6 and Rrup = 25-30 km across all periods and for Mw = 6.2-6.4 and Rrup = 30-35 km at short periods. For strike-slip events, there seems to be three intervals showing high regional dependence of GMs. To conclude, authors believe that supplementary data is required to make a definitive statement in the whole magnitude and distance range. In case of negligible regional differences, such investigation would be beneficial for development of future GMPEs in Iran to overcome incompleteness of data and existence of gaps in distance-magnitude intervals.}, keywords = {Iran,California,Regional Dependency,Analysis of variance,Strong Ground Motion Database,Attenuation Relationships}, title_fa = {بررسی آماری وابستگی منطقه ای جنبش‌های قوی زمین در ایران و کالیفرنیا با استفاده از تحلیل واریانس}, abstract_fa = {در این مقاله بررسی آماری دقیقی از میزان وابستگی منطقه ای جنبش‌های قوی زمین در سه منطقه تکتونیکی 1) البرز- آذربایجان-کوپه داغ، 2) ایران مرکزی و 3) زاگرس با استفاده از روش تحلیل واریانس (ANOVA) مورد مطالعه قرار گرفت. در این تحلیل‌ها از مؤلفه‌های افقی شتاب طیفی در طیف وسیعی از پریود (01/0 تا 5 ثانیه) استفاده شد. بانک داده جنبش قوی زمین ایران متشکل از 1943 زوج رکورد شتاب حاصل از 426 زمین‌لرزه با بزرگای گشتاوری 5/4 تا 7/7 می باشد که توسط 680 ایستگاه شتاب‌نگاری ثبت شدند. در این مطالعه به منظور ترکیب مقادیر شتاب طیفی افقی از پارامتر GMRotI50 [1] که مستقل از جهت قرارگیری سنسورهای ثبت شتاب‌نگاشت نسبت به یکدیگر است استفاده شد. برای اولین بار مشخصاتی نظیر فاصله گسیختگی (نزدیک‌ترین فاصله به صفحه گسیختگی) و مکانیسم گسلش برای تمامی زلزله ها برآورد شد. برای 63 ایستگاه مقدار سرعت موج برشی در 30 متر فوقانی (V_S30) با استفاده از فرکانس اصلی ساختگاه و رویکرد مبتنی بر روش نسبت طیفی افقی به عمودی [2] تعیین شد. نتایج حاصل از این تکنیک حاکی از امکان ترکیب داده‌های ثبت شده در سه منطقه تکتونیکی و تشکیل پایگاه جنبش قوی زمین واحد برای کل ایران می باشد. تعداد 5902 رکورد از 217 زلزله در کالیفرنیا از بانک NGA-West2 استخراج و امکان ترکیب آنها با رکوردهای ایران از طریق تحلیل واریانس ارزیابی شد. در مورد تشابه جنبش‌های قوی ایران و کالیفرنیا نمی توان اظهارنظر قطعی داشت و داده‌های بیشتری از ایران مورد نیاز می باشد.}, keywords_fa = {بانک داده های جنبش قوی زمین,روابط کاهندگی,وابستگی منطقه ای,آنالیز واریانس,ایران,کالیفرنیا}, url = {http://www.bese.ir/article_240389.html}, eprint = {http://www.bese.ir/article_240389_e9c727e3398016b704a12c6c350b5fee.pdf} } @article { author = {Ranjbar Karkanaki, Asadollah and Ganjian, Navid and Askari, Faradjollah}, title = {Pseudo-Static Stability Analysis of Retaining Walls Using Upper-Bound Approach}, journal = {Bulletin of Earthquake Science and Engineering}, volume = {6}, number = {2}, pages = {53-67}, year = {2019}, publisher = {International Institute of Earthquake Engineering and Seismology}, issn = {2476-6097}, eissn = {2476-6100}, doi = {}, abstract = {Given the extensive use of cantilever retaining walls in construction and development projects, optimal design and analysis of these walls with due attention to static and seismic loads is a typical engineering problem. As a general rule, a designer seeking to use the Upper Bound Limit Analysis and Limit Equilibrium Method to determine the forces acting on a retaining wall should first search for the mechanism of critical failure. During this procedure, the shape of failure surface can be considered to be planar or circular and failure mechanism can be considered to be translational, rotational, or a combination of multiple scenarios. In the present study, the Upper Bound Limit Analysis Method is used to determine the active pressure on the wall. The failure mechanism consists of two triangular wedges used to determine the active pressure on the wall, and a genetic algorithm is used to optimize the failure wedges. The current results show a good agreement with the results of Coulomb and Rankine Method.The first step for optimal design of cantilever retaining walls is to check their internal and external stability against overturning, sliding, and bearing capacity failure based on a set of assumed dimensions. This initial design should be then completed by checking the wall’s internal stability against shear and bending failures. In case of any change in wall dimensions, the design should be modified such that all factors of safety remain higher than allowable limits and the cost of concrete and steel bars be minimized. All previous works on this subject have only focused on optimizing the structural components of retaining wall, irrespective of the state of its backfill. In the present study, the upper bound limit analysis method was used to determine the shape of critical failure wedges of a retaining wall and its optimal dimensions, and then the formulas provided by ACI 318-05 were used to check its internal stability. The factors of safety against overturning, sliding, and bearing capacity failure were assessed by the limit equilibrium and limit analysis techniques. Given the reciprocal influence of factors of safety and wall dimensions and geometry, the wall’s optimum dimensions the shape of critical failure wedges needed to be determined simultaneously. The results of (upper bound) limit analysis on the stability of retaining wall showed a good agreement with the results of limit equilibrium method and finite element analysis. These results showed that when using limit analysis to determine the most critical instability states of a retaining wall, the critical conditions of failure mechanisms should be checked simultaneously with the optimal structural conditions. This study also used the proposed algorithm to determine the critical direction of earthquake acceleration coefficients. The critical direction of earthquake acceleration coefficient was defined as the direction that maximizes the active force exerted on the wall and minimizes the safety factor for wall stability. The results obtained in this study are in good agreement with the results of similar studies that have been based on limit equilibrium method and finite element analysis. The critical failure mechanism was determined through optimization with genetic algorithm and analysis was validated by comparing the obtained results with the results of other methods. Also, the results show that the geometric dimensions of the wall affect its safety factors and the active pressure on the wall. Consequently, for determination of the most critical state of failure (the lowest safety factors and the highest active pressure), the failure wedges should be optimized while simultaneously determining the optimal wall geometry that can induce the critical state of soil failure. As the results show, in all cases, the values for the safety factors against stability obtained by the Upper Bound Limit Analysis are higher than the allowable values specified by regulations and are in good agreement with the results from the Finite Element Method. Therefore, the use of the limit analysis method (based on the proposed algorithm) with an allowable safety factor higher than values specified by regulations can return results close to those of the conventional methods commonly used for the design of cantilever retaining walls. The results suggest that complementary studies on the subject may produce allowable safety factors for checking the external stability of cantilever retaining walls through the use of the Upper Bound Limit Analysis Method.}, keywords = {Retaining Wall,Upper-bound Limit Analysis,Safety factor,Seismic Coefficients,genetic algorithm}, title_fa = {تحلیل شبه استاتیکی پایداری دیوارهای حائل به روش مرز بالا}, abstract_fa = {تحلیل و طراحی دیوارهای حائل از جمله مسائل رایج در مهندسی ژئوتکنیک می‌باشد. در تحقیق حاضر الگوریتم جدیدی برای طراحی دیوارهای حائل طره­ای در شرایط زلزله به روش مرز بالای تحلیل حدی ارائه شده است. از این الگوریتم می‌توان برای طراحی و کنترل شرایط پایداری دیوارها، بر اساس مکانیسم‌های ارائه شده استفاده نمود. از ویژگی‌های این الگوریتم تعیین شرایط بحرانی گوه­های گسیختگی برای رسیدن به حداقل ضرایب اطمینان پایداری و ماکزیمم نیروی محرک وارد بر دیوار، هم‌زمان با تعیین راستای بحرانی ضرایب شتاب زلزله طرح می‌باشد. در تحقیق حاضر بر اساس الگوریتم پیشنهادی راستای بحرانی ضرایب شتاب زلزله تعیین شده است. در این حالت راستای بحرانی ضریب شتاب زلزله نه فقط بر اساس ماکزیمم‌سازی نیروی محرک وارد بر دیوار، بلکه به‌منظور حداقل‌سازی ضرایب اطمینان پایداری نیز تعیین می­شوند. در تعیین شرایط بحرانی گوه­های گسیختگی از روش بهینه­سازی الگوریتم ژنتیک استفاده شده و نتایج عددى به‌دست‌آمده به‌منظور تعیین اعتبار پاسخ­هاى تحلیلی، با نتایج دیگر روش­ها مقایسه شده است.}, keywords_fa = {دیوار حائل,روش‌های حدی,ضرایب لرزه‌ای,ضرایب اطمینان پایداری,الگوریتم ژنتیک}, url = {http://www.bese.ir/article_240390.html}, eprint = {http://www.bese.ir/article_240390_d4bee7a84dabda8b622f27645516a73e.pdf} } @article { author = {Jahankhah, Hossein and Alidoosti, Ali}, title = {Extension of Common Seismic Risk Evaluation Equations to be Applicable for Complex and Wise Systems}, journal = {Bulletin of Earthquake Science and Engineering}, volume = {6}, number = {2}, pages = {69-84}, year = {2019}, publisher = {International Institute of Earthquake Engineering and Seismology}, issn = {2476-6097}, eissn = {2476-6100}, doi = {}, abstract = {In this article, a uniform framework is presented that has the capability to be used in multi hazard risk evaluation, specifically seismic hazards and hazards related to wise threats. In this stream, first, common equations for seismic risk evaluation are completed in a more general pattern. The main novelty of this phase was providing the direct connection between every two parameters without any intervening third parameter. To show the performance of such re-derived equations, they are implemented on a sample case selected from petrochemical industry, where a vessel mounted on skirt is falling on a pipe rack. It is illustrated that traditional equations cannot predict complex risks like overturning of one equipment on another one. In spite of that, new proposed equations can simply include such irregular happenings and hence would provide more accurate risk estimates. In the next step, the state and wiseness parameters are added to the revised equations, introduced above, which adds the capability of applying these equations against wise threats. The wiseness parameters implemented in these equations are the knowledge of the owner about the asset, the knowledge of the owner about threats, the capability of owner to process the available knowledge and take preventive actions, the knowledge of wise threat about target asset, the knowledge of wise threat about attacking capabilities and at the wise threat ability to process the available knowledge and take offensive actions. In this part, again, the high flexibility and performance of new proposed equations is shown for different states of owner-attacker knowledge through several examples. These examples cover blind attack, wise attack, wise attacker against owner with restricted knowledge, wise attacker against owner with restricted processing and acting capabilities and, at last, attacker with restricted knowledge against wise owner. In the final step, the applicability of proposed equations for cases with dynamic variable states and dynamic owner-attacker knowledge levels are illustrated in an example. It is expressed that how dynamic parameters can be included, through revising probability distribution functions, in the proposed framework. It should be confirmed that the presented equations can be reduced to the traditional form which is common in current seismic risk evaluation practice. Also it should be mentioned that the above equations just form the basic framework in risk evaluation and in order to implement them in real cases, each term would need to be expanded to several new parts. Besides, the required probability distribution equations should be provided for every specific problem distinctly.}, keywords = {Seismic Risk,Complex systems,Owner and Attacker Knowledge}, title_fa = {توسعه روابط ریسک لرزه‌ای برای سیستم‌های پیچیده و تعمیم آن به مسائل مواجه با تهدیدهای هوشمند}, abstract_fa = {در محاسبات متداول ریسک لرزه‌ای عموماً ارتباط میان پارامترهای اثرگذار به‌صورت زنجیره‌ای دیده می‌شود. این نگاه امکان برقراری مستقیم ارتباط میان حلقه‌های غیرمجاور زنجیره پارامترها را سلب می‌نماید. تحت قید مذکور دامنه استفاده از روابط متداول محاسبه ریسک در مجموعه‌های پیچیده محدود می‌شود. در این تحقیق با بازنویسی روابط محاسبه ریسک لرزه‌ای و ایجاد امکان ارتباط میان حلقه‌های غیرمجاور از پارامترها، امکان افزایش کارایی روابط محاسبه ریسک لرزه‌ای فراهم آمده است. در ادامه با افزودن پارامترهای هوشمندی به معادلات محاسبه ریسک لرزه‌ای، امکان استفاده از روابط مذکور در برآورد ریسک تهاجم‌های هوشمند ایجاد شده است. این افزایش قابلیت با ارائه مثال‌های متعدد برای حالات مختلف مواجهه با تهدیدهای هوشمند مورد بررسی قرار گرفته است. در نهایت نحوه تعمیم کاربرد چارچوب پیشنهادی برای حالاتی که پارامترهای هوشمندی در طول تهاجم به‌صورت دینامیکی تغییر می‌نماید تشریح شده است.}, keywords_fa = {توسعه روابط ریسک لرزه‌ای,تهدیدهای هوشمند,پارامترهای هوشمندی,ریسک استاتیک و دینامیک}, url = {http://www.bese.ir/article_240391.html}, eprint = {http://www.bese.ir/article_240391_e975487e4420d4972b6eafb6a5bbde79.pdf} } @article { author = {Borghei Razavi, S. Mohsen and Nateghi Elahi, Fariborz}, title = {Seismic Assessment of Threaded Connections in the Power Industry}, journal = {Bulletin of Earthquake Science and Engineering}, volume = {6}, number = {2}, pages = {85-97}, year = {2019}, publisher = {International Institute of Earthquake Engineering and Seismology}, issn = {2476-6097}, eissn = {2476-6100}, doi = {}, abstract = {Lifelines refer to a set of structures, facilities, and equipment that perform the task of storing, supplying, transmitting, and distributing vital needs including water, electricity, gas, or collection, storage, treatment or recycling of wastewater and waste, or communication including landline and telephone. The earthquake phenomenon is one of the natural disasters that causes many deaths, financial and environmental damages every year. Earthquake and industrial systems retrofit against earthquake due to repeated changes and evolution of regulations in recent decades is inevitable. The first step in reinforcing structures is to determine their vulnerability to earthquakes. The purpose of seismic vulnerability analysis is to examine the equipment, communication, safety and performance of a complex at the time of the earthquake. Using this approach (checking the performance of pipelines in past earthquakes), with the appropriate speed and cost, one can determine the areas with the highest level of risk, and for the next steps, which include preparation of retrofit plans and finally retrofit implementation, prioritized. One of the ways to assess the vulnerability is to use lessons learned from past earthquakes and the behavior of equipment against seismic forces. This approach is a rational and defensible approach because the actual conditions of the complex are considered and the seismic behavior of similar equipment in past earthquakes is investigated and the results are evaluated by combining information and engineering judgment, showing a common and widely used theme in the industry. According to recent earthquakes, the most common damage occurred in industrial centers and pipelines in joints, which is one of the weakest types of thread joints, with the most damage occurring in past earthquakes. Seismic evaluation of thread connections is one of the most important issues in oil and gas lines, transmission lines, grid lines and in the power plant industry as damage to these lines will cause crisis during and after the earthquake.The transfer of petroleum and gas products to industrial centers is carried out by pipelines, which are one of the cheapest, fastest and most reliable means of pipeline being a key member of lifelines. Seismic evaluation of thread connections is one of the most important issues in oil and gas lines and in the power plant industry as damage to these lines will cause crisis during and after the earthquake. In this study, one of the most common thread connections is used for modeling. After modeling and loading, the connection was evaluated in both daily and buried conditions. A flexible piece called an accordion is also used at the junction to reinforce the connection. In addition to the accordion length, the support conditions and the accordion material are considered in the modeling. According to the results, the most stress and damage to the connection occurs on the pin as well as in the last thread involved with the pin with the box. It was also found that stress at the joint is independent of the underlying conditions and is directly related to the material of the joints, and the use of accordion was found to be an appropriate approach to reinforce such joints.}, keywords = {Seismic Analysis,Lifelines,Retrofitting,Threaded Connection,Buried Tube,Surface Tube,Accordion}, title_fa = {ارزیابی لرزه‌ای آسیب‌پذیری اتصالات رزوه‌ای در صنعت نیروگاهی}, abstract_fa = { انتقال فرآورده‌های نفتی و گاز در مراکز صنعتی توسط خطوط لوله که یکی از روش‌های ارزان‌قیمت، سریع و مطمئن است، انجام می‌گیرد که خطوط لوله یکی از اعضای اصلی شریان‌های حیاتی هستند. ارزیابی لرزه‌ای اتصالات رزوه‌ای از مهم‌ترین مسائل در خطوط نفت و گاز و در صنعت نیروگاهی است زیرا آسیب در این خطوط سبب ایجاد بحران در حین و پس از زلزله خواهد شد. در این مطالعه از یکی از متداول‌ترین اتصالات رزوه‌ای برای مدل‌سازی استفاده شده است. پس از مدل‌سازی و بارگذاری، اتصال مورد نظر در دو حالت رو زمینی و مدفون مورد ارزیابی قرار گرفت. برای مقاوم‌سازی اتصال نیز از یک قطعه انعطاف‌پذیر به نام آکاردئونی در محل اتصال استفاده شده است. علاوه بر طول آکاردئونی، شرایط تکیه‌گاهی و جنس آکاردئونی در مدل‌سازی‌ها در نظر گرفته شده است. بر اساس نتایج به‌دست‌آمده بیشترین تنش و آسیب در اتصال بر روی پین و همچنین در آخرین رزوه‌ی درگیر پین با باکس اتفاق می‌افتد. همچنین مشخص شد تنش در محل اتصال مستقل از شرایط تکیه‌گاهی است و با جنس مصالح رابطه مستقیم دارد و مشخص گردید استفاده از آکاردئونی رویکرد مناسبی جهت مقاوم‌سازی این‌گونه اتصالات می‌باشد.}, keywords_fa = {تحلیل لرزه‌ای,شریان‌های حیاتی,مقاوم‌سازی,اتصال رزوه‌ای,لوله مدفون,لوله سطحی,آکاردئونی}, url = {http://www.bese.ir/article_240392.html}, eprint = {http://www.bese.ir/article_240392_49192bc0103f1da40761f05835617db3.pdf} } @article { author = {Khodayari, Rasoul and Bahar, Omid and Ghafory-Ashtiany, Mohsen}, title = {Introducing a Method for Identification of All Dynamic Characteristics Matrices of Shear Buildings Using Output-Only Data}, journal = {Bulletin of Earthquake Science and Engineering}, volume = {6}, number = {2}, pages = {99-117}, year = {2019}, publisher = {International Institute of Earthquake Engineering and Seismology}, issn = {2476-6097}, eissn = {2476-6100}, doi = {}, abstract = {Nowadays, system identification methods have found special place in civil engineering due to extended application in health monitoring and damage detection of structures. Among these, due to limitations caused by stimulation of large scale actual structures, structure engineers are mostly leading toward identification methods based on output-only data. In this study, a method was proposed based on identification of Stochastic Subspace Identification (SSI) method in time domain to identify all structural matrices including mass, damping and stiffness in shear buildings. This method is highly able to identify structural matrices even in working with noise-polluted data. When using SSI with reviewing realization theory, we have never proper information about real degrees of freedom of the system. Hence, system matrices are identifiable in various forms, all of which are true realizations of the system. To explore the main matrices of structural model, the proposed method relies on finding realization of the minimal matrix of the system in the classical form. To evaluate the effectiveness of suggested method, two numerical models of 3 and 5 stories is used. Results of the numerical analysis indicate accuracy of suggested identification method, even in using high noise polluted data.}, keywords = {System Recognition,Dynamic Feature Matrix,Output-Only,Random Subspace,Shear Structure}, title_fa = {ارائه‌ی روشی برای شناسایی ماتریس‌های مشخصه دینامیکی سازه‌‌های برشی با استفاده از داده‌های خروجی}, abstract_fa = {امروزه روش‌های شناسایی سیستم‌ها به سبب دامنه وسیع کاربرد در مباحث پایش سلامت و تشخیص خرابی سازه‌ها جایگاه ویژه‌ای در مهندسی عمران یافته است. از این میان، به علت محدودیت‌هایی که به لحاظ تحریک سازه‌های حقیقی بزرگ‌مقیاس وجود دارد، مهندسان سازه بیشتر به سمت روش‌های شناسایی بر اساس داده‌های خروجی سوق پیدا نموده‌اند. در این مقاله روشی بر اساس شناسایی زیرفضای تصادفی در حوزه زمان جهت شناسایی کلیه‌ی ماتریس‌های مشخصه دینامیکی سازه‌های برشی شامل جرم، سختی و میرایی در شرایط کار با داده‌های آلوده به نوفه‌ی بالا پیشنهاد شده است. روش حاضر بر یافتن تحقق کمینه ماتریس سیستم به فرم کلاسیک از میان بی‌نهایت ماتریس سیستم قابل شناسایی به روش شناسایی زیر فضای تصادفی بر اساس تئوری تحقق تکیه دارد و در کنار قابلیت‌ها، محدودیت‌هایی نیز دارد که عمده این محدودیت‌ها شامل وابسته بودن دقت به دقت روش‌های اولیه و نیز لزوم داشتن وضوح دامنه‌ی پاسخ و طول مدت کافی برای رکوردگیری می‌باشد. برای ارزیابی کارایی روش پیشنهادی از دو مدل عددی 3 و 5 طبقه بهره گرفته شده است. با توجه به خطای زیر سه درصد برای تمامی حالات، نتایج تحلیل‌های عددی حاکی از صحت و دقت روش شناسایی پیشنهادی حتی در هنگام استفاده از داده‌های آلوده به نوفه‌ی بالا است.}, keywords_fa = {شناسایی سیستم,ماتریس مشخصات دینامیکی,خروجی تنها,زیر فضای تصادفی,سازه های برشی}, url = {http://www.bese.ir/article_240393.html}, eprint = {http://www.bese.ir/article_240393_951e6976a272bd88d8151c6194b05012.pdf} } @article { author = {Mohammadi, Majid and Inanloo, Nahid}, title = {Applying Post-Tensioned Connections to Prevent Progressive Collapse of Buildings}, journal = {Bulletin of Earthquake Science and Engineering}, volume = {6}, number = {2}, pages = {119-131}, year = {2019}, publisher = {International Institute of Earthquake Engineering and Seismology}, issn = {2476-6097}, eissn = {2476-6100}, doi = {}, abstract = {In progressive collapse, a local failure in a building leads to the failure of the adjoining members or even the entire structural collapse. When a single column (or a wall) is removed, beams and slabs act together to develop catenary action. This prevents collapse progression by redistributing gravity loads through reliable paths. If a structure has good alternative loading paths, the initial failure will not expand to other parts of the structure and thus the damage will be restricted. In this research, the influence of applying post-tensioned connections, which can increase catenary action, to prevent progressive collapse is investigated. A post-tensioned (PT) steel moment resisting frame is a self-centering earthquake resistant steel frame having post-tensioned strands, compressing the beam flanges against the column flanges at the connections. The post-tensioned strands contribute to the moment capacity of the connections and provide an elastic restoring force to return the frame to its pre-earthquake position. The most important advantage of the PT connection is that the beams and columns remain elastic, while inelastic deformations (and damage) in the connections provide considerable energy dissipation. The damage in the connection occurs mostly in the angles which can be easily replaced after the earthquake. In this regard, two types of six-story, four-bay steel frames are designed; one having post tensioned and the other having regular rigid connections. The frames are modeled in OpenSees program and their progressive collpse possibilities are studied. To study the influence of the design parameter (αa) on the progressive collapse, five different details are considered for the PT connections. The resultant frames have different αas (αa =0.95, 1.1, 1.25, 1.4 and 1.55), where αa is the ratio of connection moment, corresponding to the angle yielding, to the design moment of the beam at the column face.To study the possibility of progressive collapse in the building, the gravity loads are firstly applied to the structure, then the column of the first floor is suddenly removed as the scenaio of the progressive collapse, based on the code, GSA. Time histories for deflections of the critical point (top of the removed column) of these frames are compared with the results of the frame having rigid connections. It has been shown that increasing αa in the frames with PT connections raises the resistance against progressive collapse and the one with αa >1.55 is even better than rigid connection frame in preventing progressive collapse. A sensitivity analysis is also carried out to study influences of the PT connection details on the progressive collapse. Different PT connections with different details can have the same αa; incresing the size of the conenction angle sections or raising the strands force can both increase αa. A six-story, four-bay steel frame is designed, having post-tensioned connections, the frame is considered as Frame A. Two other frames are also designed with greater αa; Frame B and Frame C have the same αa in their PT connections: Frame B has the same connection angle sections of Frame A, but higher T0. In Frame C, the angles’ size is just increased. For each of these cases (Frame A, Frame B and Frame C) the gravity loads are firstly applied to the structure, and then progressive collapse analysis is performed dynamically by sudden removal of the middle column in the first floor. Deflections of the critical points (top of the removed column) for these frames are compared. It has been shown that if the middle column at the first floor of Frame B is suddenly removed, the node at the top of the removed column vibrates vertically with the maximum and residual displacement of 10.37 cm and 4.85 cm, respectively. The maximum vertical displacement and residual displacements in the Frame C under the same scenario are 11.21 cm and 8.56 cm, respectively. Comparing the results of these two frames shows that increasing the strands posttensioning force is more effective against the progressive collapse. In summary, the obtained results of this paper show that applying PT connections with αa >1.55 is more efficient against progressive collapse than moment resisting frames with regular rigid connections; the greater αa supplies higher resistance against such collapse. This can be applied both by raising the connection strands’ force or increasing the connection angle section size; however, the former is more efficient in preventing progressive collapse.}, keywords = {Post-Tensioned Connection,Progressive Collapse,Catenary Action,Dynamic Analysis}, title_fa = {اثر اتصالات پس کشیده کابلی بر خرابی پیش‌رونده سازه های فلزی}, abstract_fa = {خرابی پیش‌رونده نوعی از خرابی در سازه است که در آن تخریب یک یا چند عضو سازه ای منجر به خرابی قسمت زیادی از سازه و حتی فروریزش کلی می گردد. به هنگام خرابی ستون در خرابی پیش‌رونده، تیرها برای مقاومت در برابر بارهای قائم به‌صورت زنجیر عمل می کنند و عواملی که بتوانند این کنش زنجیری را تقویت کنند عملاً باعث جلوگیری از گسترش خرابی پیش‌رونده خواهند شد. یکی از راهکارهای افزایش کنش زنجیره ای استفاده از اتصالات پس کشیده کابلی می باشد. این نوع اتصال در سال 2001 پیشنهاد گردید که در آن از نبشی زیر سری و بالا سری برای کنترل تغییر شکل های پلاستیک و از تعدادی کابل با مقاومت بالا برای ایجاد خاصیت خود مرکزی استفاده شد. در تحقیق حاضر اثر این نوع اتصال (اتصال کابلی پس کشیده) بر خرابی پیش‌رونده مورد بررسی قرار می گیرد. مهم‌ترین پارامتری که در طراحی قاب دارای چنین اتصالی که اصطلاحاً قاب پس‌کشیده نامیده می‌شود وجود دارد ضریب αa است که افزایش آن منجر به قوی‌تر شدن اتصال می گردد. به بیان دیگر پارامتر αa بیانگر نسبت لنگر اتصال به هنگام تسلیم نبشی به لنگر طراحی تیر در وجه ستون می باشد. هدف از این مطالعه یافتن حداقل مقدار αa مناسب برای مقابله با خرابی پیش‌رونده است. بدین‌منظور قاب های پس‌کشیده با ضرایب مختلف αa با استفاده از برنامه اپنسیس  مدل‌سازی و نتایج آن با قاب مشابهی که دارای اتصالات کاملاً گیردار است مقایسه شده است. صحت مدل‌سازی اتصالات پس‌کشیده با نتایج آزمایشگاهی موجود در ادبیات فنی انجام شده است. نتایج تحلیل‌ها نشان می دهد در صورتی‌که پارامتر طراحی  αa بزرگ‌تر از 55/1 اختیار گردد مقاومت سازه دارای اتصال پس‌کشیده در برابر خرابی پیش‌رونده از قاب مشابه دارای اتصالات گیردار بیشتر می-شود. همچنین یک تحلیل حساسیت برای یافتن مؤثرترین خصوصیت اتصال پس‌کشیده در افزایش مقاومت سازه در برابر خرابی پیش‌رونده انجام شده است که نتایج آن نشان می دهد افزایش نیروی پس‌کشیدگی کابل ها بیشترین تأثیر را بر کاهش پاسخ سازه در برابر خرابی پیش‌رونده دارد.}, keywords_fa = {اتصال پس‌کشیده,خرابی پیش‌رونده,کنش زنجیره‌ای,تحلیل دینامیکی}, url = {http://www.bese.ir/article_240385.html}, eprint = {http://www.bese.ir/article_240385_ef9a7078c8e1e1e5ba86c219f74a6cf4.pdf} } @article { author = {Tabeshpour, Mohammed Reza and Karimi, Komeil}, title = {Shear Failure of Concrete Infilled Frame}, journal = {Bulletin of Earthquake Science and Engineering}, volume = {6}, number = {2}, pages = {133-143}, year = {2019}, publisher = {International Institute of Earthquake Engineering and Seismology}, issn = {2476-6097}, eissn = {2476-6100}, doi = {}, abstract = {Infill walls are one of the most important and problems in behavior of concrete structures during earthquake. This matter has become so important over the past few years as a result of the great damages caused by recent earthquakes. Masonry infill walls have negative and positive effects in building response.In this paper interaction of masonry infill with concrete frame with 3 bays and 5 stories is surveyed. Masonry infill walls are modeled by node to node equivalent struts and SAP2000 is used for analysis. The results show that shear reinforcement of concrete columns in ordinary design is not sufficient and shear failure is occurred. Shear failure in columns cause loosing axial capacity of columns and results in collapsing of buildings. Stirrups should be designed for maximum forces in order to avoid this brittle failure.An ideal form of structure is considered normally in order to analyze the structure, which undoubtedly has differences with its actual model. The actual model has also some differences with the computational model such as defects in the existence of infill walls, which will be neglected from their effects on the structure analysis and design. Distribution of these elements and their effects on stiffness and lateral strength of the constructions have generally overlooked during the design process. Seismic retrofitting of the structures needs detailed evaluation of these elements in reaction of structures to the applied loading. Although existence of the infill walls basically provides higher stiffness and strength for the frames, their detrimental effects on the structure performance is ignored due to the lack of adequate information about the behavior of frames and infill walls.According to the failure mode of structures with masonry infill walls, it is seen that masonry infill walls have positive and negative effects on structure. Because of considerable stiffness and resistance of infill walls, existing of that should cause high torsion in stiffness and resistance of structure in plan and view. Thus an important question is: how the interaction between masonry infill walls and concrete frame should be considered in design of structures for preventing brittle failure of columns in future earthquakes. From a technical point of view, the modeling is categorized into:i) Detailed modeling (micro)ii) Simple modeling (macro)The first category is based on the definition of finite element model of infill wall and is solved by formal plasticity and elasticity methods. In the second category, a general behavior of infill wall is important, and in this case one or several elements are used to model the behavior of infill wall. A 5-story frame with 3 bays has been investigated in this study. All frames have been filled by masonry walls with thickness of 0.23 m. Lateral force resisting system is intermediate concrete moment frame and the type II of soil according to Iranian seismic code of practice (Standard No. 2800). In this method of analysis, by assessing the target displacement of structures, lateral forces are increasingly applied to the structural model up to control point displacement achieve target displacement. Control point displacement is considered at roof level. An important point is adjacent the masonry walls to concrete frame cause intensive shear force at top and bottom of columns. Inadequacy of shear reinforcement in columns cause shear failure and also the results confirm it. Shear failure will eliminate the axial capacity of columns, and finally the building will collapse.}, keywords = {Masonry infill,Interaction,Shear Failure,Nonlinear Analysis}, title_fa = {شکست برشی قاب بتنی در اندرکنش با دیوار پرکننده آجری}, abstract_fa = {وجود دیوارهای پرکننده آجری و چگونگی اتصال آن به قاب بتنی بحث بسیار مهم و تعیین‌کننده در عملکرد سازه در مقابل زلزله است. این بحث در سال­های اخیر با توجه به زلزله­های پیش­آمده و خرابی­های حاصل از این زلزله­ها اهمیت زیادی پیدا کرده و مورد بررسی و تحقیق قرارگرفته است. دیوار پر­کننده علاوه بر اثرات مثبت در سازه دارای اثرات منفی نیز می­باشد. در این مقاله به بررسی اندرکنش بین قاب بتنی و دیوار پرکننده آجری در یک قاب 3 دهنه 5 طبقه پرداخته خواهد شد. دیوار پرکننده آجری به‌صورت دستک معادل قطری ستون به ستون بر طبق روابط دستورالعمل بهسازی لرزه­ای تعریف شده و برای مدل‌سازی و تحلیل استاتیکی غیرخطی از نرم‌افزار SAP 2000 استفاده شده است. نتایج حاصل بیانگر این است که خاموت برشی موجود در ستون­های بتنی در طراحی معمولی جواب­گوی برش ایجاد شده در بالا و پایین ستون­های متصل به دیوار پرکننده آجری نیست و باعث تشکیل مفصل برشی و شکست برشی در این نواحی از ستون می­شود. شکست برشی در ستون­های یک سازه باعث از بین رفتن ظرفیت محوری ستون و در نتیجه فروریزش سازه خواهد گردید. برای جلوگیری از این شکست باید خاموت­ها برای بیشینه نیروها طراحی شود.}, keywords_fa = {دیوار پرکننده آجری,اندرکنش قاب بتنی و دیوار,شکست برشی,تحلیل غیرخطی}, url = {http://www.bese.ir/article_240386.html}, eprint = {http://www.bese.ir/article_240386_1c0bfdf85b931eb5635798e88652fa88.pdf} } @article { author = {Manie, Salar and Jami, Ehsan}, title = {Evaluation of Seismic Performance of Concrete Structures Retrofitted with FRP Composites}, journal = {Bulletin of Earthquake Science and Engineering}, volume = {6}, number = {2}, pages = {145-157}, year = {2019}, publisher = {International Institute of Earthquake Engineering and Seismology}, issn = {2476-6097}, eissn = {2476-6100}, doi = {}, abstract = {The present paper aims at investigating the effects of strengthening structural components of reinforced concrete (RC) frames using FRP composite on their seismic performance. For this purpose, in a case study, the seismic performance of a typical building with moment frames in both plan directions as the lateral force resisting system and retrofitted with FRP wraps to deal with the weaknesses arose from increase in the number of stories compared to the original structure for occupancy reasons has been evaluated. Strengthening of the columns has been performed by considering the axial force and the biaxial bending moments at target displacement, while that of the beams has been performed based on the bending moments at the target displacement. The seismic performance of the strengthened structure has been investigated by nonlinear analysis methods based on concentrated plastic hinges model following ASCE 41-17 standard procedures. The results show that the use of FRP composites in strengthening RC components significantly improves the seismic performance by reducing the number of plastic hinges as well as the plastic rotation demands at the target displacement of the retrofitted structure.}, keywords = {FRP Composites,Seismic Retrofit,Reinforced Concrete,Seismic Performance}, title_fa = {ارزیابی عملکرد لرزه‌ای ساختمان‌های بتنی قاب خمشی تقویت شده با کامپوزیت‌های FRP}, abstract_fa = {این مقاله به بررسی تأثیر تقویت اجزای قاب‌های خمشی بتن‌آرمه با مصالح FRP بر رفتار لرزه‌ای آنها می‌پردازد. برای این منظور، در یک مطالعه موردی، عملکرد لرزه‌ای یک ساختمان با سیستم باربر قاب خمشی که به دلایل کاربری، افزایش تعداد طبقات سازه اولیه منجر به لزوم تقویت اجزای آن شده مورد ارزیابی قرار گرفته است. تقویت ستون‌ها با در نظر گرفتن تلاش محوری و نیز آثار توأم گشتاورهای خمشی دو محوره در جابه‌جایی هدف و تقویت تیرها بر مبنای تلاش خمشی حاکم در جابه‌جایی مذکور انجام گرفته است. عملکرد لرزه‌ای سازه تقویت شده به روش‌های غیرخطی مبتنی بر منحنی‌های رفتاری اصلاح شده مفاصل پلاستیک از نوع فایبر و با استفاده از روند پیشنهادی دستورالعمل بهسازی لرزه‌ای ساختمان‌های موجود (نشریه شماره 360) بررسی شده است. نتایج نشان می‌دهد که استفاده از مصالح FRP در تقویت اجزای بتن‌آرمه به میزان قابل‌توجهی باعث بهبود عملکرد لرزه‌ای از طریق کاهش تعداد مفاصل پلاستیک و همچنین دوران‌های پلاستیک آنها در نقطه عملکرد سازه بهسازی شده گردیده است.}, keywords_fa = {مصالح FRP,تقویت اجزا بتنی,عملکرد لرزه‌ای,بهسازی لرزه‌ای}, url = {http://www.bese.ir/article_240387.html}, eprint = {http://www.bese.ir/article_240387_04fb192ad4ca381f6034f00878000044.pdf} }