@article { author = {Xu, Longjun and Zhang, Hongzhi and Xu, Hao and Xie, Lili}, title = {Seismic Design Parameters Derived from Typical Near-Fault Strong Motions}, journal = {Journal of Seismology and Earthquake Engineering}, volume = {14}, number = {4}, pages = {239-250}, year = {2013}, publisher = {International Institute of Earthquake Engineering and Seismology}, issn = {1735-1669}, eissn = {2821-2541}, doi = {}, abstract = {Based on typical near-fault ground motions, relations between motion pulse amplitudes and periods are utilized to scale the difference of near-fault motions between rock and soil sites. Features of ground motion pseudo-velocity response spectra (PVS), normalized pseudo-velocity spectra (NPVS) and bi-normalized pseudo-velocity spectra (BNPVS) are examined by considering the influence of site conditions. Observations show that, the use of parameters PGV and Tp for the normalization of PVS is applicable. They can effectively reduce the scatter in the response spectra of long period range; ground motion pulse waveforms are affected by local site conditions, BNPVS values of soil sites are larger than those of rock sites at normalized period T/Tv less than about 0.7, while at relative periods larger than 0.7 the reverse is true; spectral peak value of BNPVS at rock sites is significantly higher than that of soil sites. Then, using simple pulses and available predictive relationships for near-fault motions, acceleration response spectra of the near-fault region are developed. The BNPVS are finally used to test the applicability of the established design spectra.}, keywords = {Near-Fault Ground Motion,Pulse,Attenuation Relations,Bi-Pseudo Velocity Spectrum,Design Spectrum}, url = {http://www.jsee.ir/article_240648.html}, eprint = {http://www.jsee.ir/article_240648_ab7a48ada8b298c18c49fda5f2853019.pdf} } @article { author = {Banimahd, Amir and Arbabi, Freydoon}, title = {Seismic Vulnerability Assessment and Development of Analytical Fragility Curves for Railroads}, journal = {Journal of Seismology and Earthquake Engineering}, volume = {14}, number = {4}, pages = {251-262}, year = {2013}, publisher = {International Institute of Earthquake Engineering and Seismology}, issn = {1735-1669}, eissn = {2821-2541}, doi = {}, abstract = {In a highly seismic country like Iran, safety of lifeline systems is of utmost importance. Thus, in order to develop reliable systems that can withstand severe earthquakes, railroad tracks should be properly designed and maintained. A useful tool for the assessment of structures under earthquake is fragility curves. For railroad tracks, which are designed to withstand landslides, liquefaction, etc., i.e. disasters other than earthquakes, an empirical approach is used to establish fragility curves with specific values for critical deformations. An analytical approach provides an attractive alternative and is used here. In order to make a large number of required analyses possible, a macro-element is developed and used for modeling the track system. In this model, the ballast and subgrade are represented by nonlinear springs. Fragility curves presented here are for different types of ties and roadbed properties. The results indicate that lighter ties (wood) will result in much lower seismic forces in the system than heavy (concrete) ties.}, keywords = {Fragility Curve,lifeline,Railroad,Finite element,Vulnerability}, url = {http://www.jsee.ir/article_240649.html}, eprint = {http://www.jsee.ir/article_240649_67445af377ee368cb199af6d24a669cd.pdf} } @article { author = {Jalili, Javad and Jafari, Mohammad Kazem and Shafiee, Ali}, title = {Measuring Pore Water Pressure Variation inside Saturated Triaxial Specimens of Low-Plastic Composite Clay under Strain-Controlled Cyclic Loading}, journal = {Journal of Seismology and Earthquake Engineering}, volume = {14}, number = {4}, pages = {263-270}, year = {2013}, publisher = {International Institute of Earthquake Engineering and Seismology}, issn = {1735-1669}, eissn = {2821-2541}, doi = {}, abstract = {As a step forward in an ongoing investigation on behavior of composite clay, which is used as the core material of some large embankment dams all over the world, a series of experiments were conducted to explore the distribution of excess pore water pressure along saturated triaxial clay specimens during cyclic loading. As the predominant feature of the composite clay behavior is the increase in excess pore water pressure in both monotonic and cyclic loadings as a consequence of increase in inclusion content, this paper focuses on formation of such pressure distribution inside the specimens in cyclic loading, by utilizing a miniature inner pressure transducer inside triaxial specimens. Specimens of pure clay and mixed material containing 40% (volumetric) ceramic beads and 60% clay were tested. Under strain-controlled cycles of 1.5% single amplitude, the expected increase of excess pore water pressure was captured at both ends and also inside the sample, which is in agreement with previous findings in this regard.}, keywords = {Composite Clay,Cyclic Triaxial Loading,Excess Pore Water Pressure,Inner Transducer,Loading Frequency}, url = {http://www.jsee.ir/article_240650.html}, eprint = {http://www.jsee.ir/article_240650_5bb9c9e14aac98568a107f2acc21fdd0.pdf} } @article { author = {Mostafazadeh, Mehrdad and Ashkpoor Motlagh, Shobeir}, title = {Source Study of some Large Earthquakes Occurred in South Eastern Iran}, journal = {Journal of Seismology and Earthquake Engineering}, volume = {14}, number = {4}, pages = {285-296}, year = {2013}, publisher = {International Institute of Earthquake Engineering and Seismology}, issn = {1735-1669}, eissn = {2821-2541}, doi = {}, abstract = {We examine the source parameters of the March 14, 1998 (Mw 6.6); March 4, 1999 (Mw 6.6); February 14, 2003 (Mw 5.6); December 26, 2003 (Mw 6.6); February 28, 2006 (Mw 6.0); earthquakes by analyzing body waveform seismograms and compiled source time function of June 11, 1981 (Ms 6.7); July 28, 1981 (Ms 7.1); November 20, 1989 (mb 5.6) events, obtained from body waveform modeling. The results from waveform modeling for the March 14, 1998; December 26, 2003 events indicate that source depth was changed between 4 and 6 km and that the mechanism was right-lateral strike-slip. Evaluation of slip vector azimuths (assuming that the west-dipping nodal plane is the fault plane) of earthquakes occurred along the Gowk and Bam faults system (changed between 142o-184o) confirm the govern tension in this area and the dominant direction of basement is northward. The source depth of earthquakes (March 4, 1999; February 14, 2003; February 28, 2006 events) in southern part of study area was changed from 22 km to 26 km and that the mechanism was dip-slip. They probably reflect the lower crust subducted zone dipping NNE direction with a low angle beneath the central Iran in this area and suggest a seismogenic layer of > 20 km thick under the deposit layers sequence. The main purpose of this study is to evaluate fault rupture, and prepare information about displacement time history on the fault. The major pulse duration of each event was determined from source time function and used to determine rupture length. Seismic moments deduced from the body wave synthetics are used for calculating displacement and stress drop. Minimum and maximum displacement and stress drop is changed from 0.15 m to 3.5 m, 3.2 bars to 79 bars, respectively. Varying the seismic moment along total duration of source time function is direct related to varying the source velocity structure did have an effect on centroid depth and seismic moment.}, keywords = {Source Parameters,Source Time Function,Waveform Modeling,Southeast Iran}, url = {http://www.jsee.ir/article_240652.html}, eprint = {http://www.jsee.ir/article_240652_1f264e06417b26b4edab6a27381fbc38.pdf} } @article { author = {Fadaee, Meysam and Jafari, Mohammad Kazem and Kamalian, Mohsen and Mustafa, Seyed Alireza}, title = {Fault Rupture Propagation in Alluvium and Its Interaction with Foundation: New Insights from1g Modelling via High Resolution Optical Image Processing Techniques}, journal = {Journal of Seismology and Earthquake Engineering}, volume = {14}, number = {4}, pages = {271-283}, year = {2013}, publisher = {International Institute of Earthquake Engineering and Seismology}, issn = {1735-1669}, eissn = {2821-2541}, doi = {}, abstract = {Earthquake fault ruptures may emerge at the ground surface causing large differential movements. Fault ruptures can cause significant damage when they emerge at or adjacent to the position of existing foundation. However, the study of recent faulting events revealed that, in some circumstances, the fault-rupture emergence is affected by the presence of buildings. A 1g modelling study, as well as validated numerical modelling was conducted to investigate how reverse faults interact with strip foundations which run parallel to the fault strike. To better understand this process, we monitor displacement field in scaled model experiments using high resolution optical image correlation techniques. High-resolution optical strain monitoring quantifies the spatial pattern of strain accumulation in our model experiments. In this paper, following the explanation of 1g model test apparatus, the steps leading to development of an image processing program are described. Afterwards, by using this tool, we investigate the interaction between fault rupture and foundation. This study confirms that fault rupture may be deviated by the foundation so that the foundation is protected from serious rotations and detachment.}, keywords = {Fault rupture,image processing,Differential movements,Foundation}, url = {http://www.jsee.ir/article_240651.html}, eprint = {http://www.jsee.ir/article_240651_7e9d659c9b1d2acd04b70d931eb6331c.pdf} } @article { author = {Malekinejad, Mohsen and Rahgozar, Reza}, title = {A Simplified Dynamic Analysis of Symmetric Tube Structures Based on Hamilton's Principle}, journal = {Journal of Seismology and Earthquake Engineering}, volume = {14}, number = {4}, pages = {297-303}, year = {2013}, publisher = {International Institute of Earthquake Engineering and Seismology}, issn = {1735-1669}, eissn = {2821-2541}, doi = {}, abstract = {In this paper, a mathematical model is presented for free vibration analysis of symmetric plan framed tube systems in tall buildings. Then, a closed form solution is derived for obtaining natural frequencies of framed tube structures. The analysis is based on continuum approach in which the framed tube structure is idealized as composed of four equivalent orthotropic plate panels. Therefore, framed tube structure is replaced by an idealized cantilever continuum representing the structural characteristics. Using the analytical method based on the Hamilton's principle and theory of differential equation by considering boundary conditions and normalization of parameters, the governing equation for free vibration of the problem is developed, and the corresponding eigenvalue equation is then derived. A theoretical method of solution is proposed to solve the eigenvalue problem, and a general solution is given to determine the natural frequencies of the framed tube structure. By following the proposed calculation procedure, frequencies of the free vibration are quickly determined. The proposed method for predicting the natural frequencies of framed tube structures is shown to give good agreement with those obtained from computer analysis; thus, the proposed method offers a simple and efficient, yet accurate, means for free vibration analysis of framed tube systems in tall buildings.}, keywords = {Tall Building,Framed Tube,Hamilton's Principle,Free vibration,Natural frequencies}, url = {http://www.jsee.ir/article_240653.html}, eprint = {http://www.jsee.ir/article_240653_68ab3c6c806de34d35bc2dba973498a5.pdf} }