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1.
The performance-based liquefaction potential analysis was carried out in the present study to estimate the liquefaction return period for Bangalore, India, through a probabilistic approach. In this approach, the entire range of peak ground acceleration (PGA) and earthquake magnitudes was used in the evaluation of liquefaction return period. The seismic hazard analysis for the study area was done using probabilistic approach to evaluate the peak horizontal acceleration at bed rock level. Based on the results of the multichannel analysis of surface wave, it was found that the study area belonged to site class D. The PGA values for the study area were evaluated for site class D by considering the local site effects. The soil resistance for the study area was characterized using the standard penetration test (SPT) values obtained from 450 boreholes. These SPT data along with the PGA values obtained from the probabilistic seismic hazard analysis were used to evaluate the liquefaction return period for the study area. The contour plot showing the spatial variation of factor of safety against liquefaction and the corrected SPT values required for preventing liquefaction for a return period of 475 years at depths of 3 and 6 m are presented in this paper. The entire process of liquefaction potential evaluation, starting from collection of earthquake data, identifying the seismic sources, evaluation of seismic hazard and the assessment of liquefaction return period were carried out, and the entire analysis was done based on the probabilistic approach.  相似文献   

2.
This article describes a new performance-based approach for evaluating the return period of seismic soil liquefaction based on standard penetration test (SPT) and cone penetration test (CPT) data. The conventional liquefaction evaluation methods consider a single acceleration level and magnitude and these approaches fail to take into account the uncertainty in earthquake loading. The seismic hazard analysis based on the probabilistic method clearly shows that a particular acceleration value is being contributed by different magnitudes with varying probability. In the new method presented in this article, the entire range of ground shaking and the entire range of earthquake magnitude are considered and the liquefaction return period is evaluated based on the SPT and CPT data. This article explains the performance-based methodology for the liquefaction analysis – starting from probabilistic seismic hazard analysis (PSHA) for the evaluation of seismic hazard and the performance-based method to evaluate the liquefaction return period. A case study has been done for Bangalore, India, based on SPT data and converted CPT values. The comparison of results obtained from both the methods have been presented. In an area of 220 km2 in Bangalore city, the site class was assessed based on large number of borehole data and 58 Multi-channel analysis of surface wave survey. Using the site class and peak acceleration at rock depth from PSHA, the peak ground acceleration at the ground surface was estimated using probabilistic approach. The liquefaction analysis was done based on 450 borehole data obtained in the study area. The results of CPT match well with the results obtained from similar analysis with SPT data.  相似文献   

3.
India is prone to earthquake hazard; almost 65 % area falls in high to very high seismic zones, as per the seismic zoning map of the country. The Himalaya and the Indo-Gangetic plains are particularly vulnerable to high seismic hazard. Any major earthquake in Himalaya can cause severe destruction and multiple fatalities in urban centers located in the vicinity. Seismically induced ground motion amplification and soil liquefaction are the two main factors responsible for severe damage to the structures, especially, built on soft sedimentary environment. These are essentially governed by the size of earthquake, epicentral distance and geology of the area. Besides, lithology of the strata, i.e., sediment type, grain size and their distribution, thickness, lateral discontinuity and ground water depth, play an important role in determining the nature and degree of destruction. There has been significant advancement in our understanding and assessment of these two phenomena. However, data from past earthquakes provide valuable information which help in better estimation of ground motion amplification and soil liquefaction for evaluation of seismic risk in future and planning the mitigation strategies. In this paper, we present the case studies of past three large Indian earthquakes, i.e., 1803 Uttaranchal earthquake (Mw 7.5); 1934 Bihar–Nepal earthquake (Mw 8.1) and 2001 Bhuj earthquake (Mw 7.7) and discuss the role of soft sediments particularly, alluvial deposits in relation to the damage pattern due to amplified ground motions and soil liquefaction induced by the events. The results presented in the paper are mainly focused around the sites located on the river banks and experienced major destruction during these events. It is observed that the soft sedimentary sites located even far from earthquake epicenter, with low water saturation, experienced high ground motion amplification; while the sites with high saturation level have undergone soil liquefaction. We also discuss the need of intensifying studies related to ground motion amplification and soil liquefaction in India as these are the important inputs for detailed seismic hazard estimation.  相似文献   

4.
The study area Delhi is second most populous city and third largest urban area in the world. Though the area lies in seismic high damage risk zone, number of high rise building and construction of mega structure at several sites of the city increase rapidly. In this study field Standard Penetration Test (SPT) values of soil collected from 750 boreholes data were analyzed to identify liquefiable sub-surface soil layers. Finally, liquefaction susceptible sub-surface maps of the region at various depth (20 m, 15 m, 12 m, 9 m, 6 m and 3 m) from ground level is prepared. The outcome of this study will be useful input for preliminary foundation and designing of earthquake resistant high rise building and seismic microzonation studies of Delhi.  相似文献   

5.
One of the most important causes of damages after the earthquakes is the soil liquefaction. Liquefaction can be defined as temporary loss in strength of saturated sandy and silty deposits under transient and cyclic loadings due to excess pore water pressure. This study includes determination of liquefaction potential in Erzincan city center and its vicinity. Due to the proximity of the North Anatolian Fault Zone, in a probable earthquake, Erzincan Province is thought to be affected. In this context, the earthquake scenarios were produced using the empirical expressions. Liquefaction potential for different earthquake magnitudes was determined. These earthquake magnitudes were selected as 6.0, 6.5, 7.0, 7.5, respectively. Liquefaction potential was investigated using standard penetration test (SPT) data. The first stage of the study, 63 boreholes in different locations was drilled and SPT was performed. Disturbed and undisturbed soil samples were taken from these boreholes. Laboratory testing was performed to determine physical properties of soil samples, and liquefaction potential analyses were examined using three methods, namely Seed and Idriss (J Soil Mech Found Div ASCE 97(9):1249–1273, 1971), Tokimatsu and Yoshimi (Soil Found 23(4):56–74, 1983), Iwasaki et al. (Soil liquefaction potential evaluation with use of the simplified procedure. International Conference on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics, St. Louis, pp 209–214, 1981). In order to complete liquefaction analysis within a short time, MATLAB program was prepared. Liquefaction potential analyses were carried out with the MATLAB program. At the final stage of this study, liquefaction potential maps were prepared for different earthquake magnitudes. The expected results will be shared with the local authorities and important engineering remedial measurements will be proposed to prevent further life losses and to mitigate property losses.  相似文献   

6.
The liquefaction potential of saturated cohesionless deposits in Guwahati city, Assam, was evaluated. The critical cyclic stress ratio required to cause liquefaction and the cyclic stress ratio induced by an earthquake were obtained using the simplified empirical method developed by Seed and Idriss (J soil Mech Found Eng ASCE 97(SM9):1249–1273, 1971, Ground motions and soil liquefaction during earthquakes. Earthquake Engineering Research Institute, Berkeley, CA, 1982) and Seed et al. (J Geotech Eng ASCE 109(3):458–483, 1983, J Geotech Eng ASCE 111(12):1425–1445, 1985) and the Idriss and Boulanger (2004) method. Critical cyclic stress ratio was based on the empirical relationship between standard penetration resistance and cyclic stress ratio. The liquefaction potential was evaluated by determining factor of safety against liquefaction with depth for areas in the city. A soil database from 200 boreholes covering an area of 262 km2 was used for the purpose. A design peak ground acceleration of 0.36 g was used since Guwahati falls in zone V according to the seismic zoning map of India. The results show that 48 sites in Guwahati are vulnerable to liquefaction according to the Seed and Idriss method and 49 sites are vulnerable to liquefaction according to the Idriss and Boulanger method. Results are presented as maps showing zones of levels of risk of liquefaction.  相似文献   

7.
The 1999 Kocaeli earthquake of Turkey (Mw = 7.4) caused great destruction to buildings, bridges and other facilities, and a death tall of about 20,000. During this earthquake, severe damages due to soil liquefaction and associated ground deformations also occurred widespread in the eastern Marmara Region of Turkey. Soil liquefaction was commonly observed along the shorelines. One of these typical sites is Sapanca town founded on the shore of Lake Sapanca. This study was undertaken as quantitative measurement of ground deformations induced by liquefaction along the southern shore of Lake Sapanca. The permanent lateral ground deformation was measured through the aerial photogrammetry technique at several locations both along the shoreline and in the town. In situ soil profiles and material properties at Sapanca area were obtained based on the data from 55 borings and standard penetration tests (SPT), and laboratory tests, respectively. The data and the empirical methods recommended by an NCEER workshop were employed to evaluate the liquefaction resistance of the soils. In addition, simple shaking tests on a limited number of samples were also performed. The permanent ground displacements were estimated from the existing empirical models, sliding block method and residual visco-elastic finite element methods. Then these estimations were compared with the observed ground displacements. The assessments suggested that liquefaction at Sapanca have occurred within Quaternary alluvial fan deposits at depths 1 and 14 m, and the major regions of liquefaction and associated ground deformations were located along the shore and creeks. The evaluations also indicated that for sites with no sand boils but with ground displacement greater than 1 m, thickness of the non-liquefiable layer was large. It is also noted that no liquefaction-induced ground surface disruption is expected at the site when the thickness of the liquefiable and non-liquefiable layers vary between 0.5 and 1.5 m, and 3.5 and 5.5 m, respectively. Except one model, all the empirical models employed in the study over-predicted the observed lateral ground displacements, while sliding block method and residual visco-elastic finite element methods yielded reasonably good results if the known properties of liquefied soils are used.  相似文献   

8.
The Arequipa June 23, 2001, earthquake with a moment magnitude of Mw 8.4 struck southern Peru, northern Chile and western Bolivia. This shallow (29 km deep) interplate event, occurring in the coupled zone of the Nazca subduction next to the southeast of the subducting Nazca ridge, triggered very localized but widely outspread soil liquefaction. Although sand blows and lateral spreading of river banks and road bridge abutments were observed 390 km away from the epicenter in the southeast direction (nearing the town of Tacna, close to the Chile border), liquefaction features were only observed in major river valleys and delta and coastal plains in the meizoseismal area. This was strongly controlled by the aridity along the coastal strip of Southern Peru. From the sand blow distribution along the coastal area, a first relationship of isolated sand blow diameter versus epicentral distance for a single event is ever proposed. The most significant outcome from this liquefaction field reconnaissance is that energy propagation during the main June 23, 2001, event is further supported by the distribution and size of the isolated sand blows in the meizoseismal area. The sand blows are larger to the southeast of the epicenter than its northwestern equivalents. This can be stated in other words as well. The area affected by liquefaction to the northwest is less spread out than to the southeast. Implications of these results in future paleoliquefaction investigations for earthquake magnitude and epicentral determinations are extremely important. In cases of highly asymmetrical distribution of liquefaction features such as this one, where rupture propagation tends to be mono-directional, it can be reliably determined an epicentral distance (between earthquake and liquefaction evidence) and an earthquake magnitude only if the largest sand blow is found. Therefore, magnitude estimation using this uneven liquefaction occurrence will surely lead to underrating if only the shortest side of the meizoseismal area is unluckily studied, which can eventually be the only part exhibiting liquefaction evidence, depending on the earthquake location and the distribution of liquefaction-prone environments.  相似文献   

9.
In this paper, the ground motion at Guwahati city for an 8.1 magnitude earthquake on Oldham fault in the Shillong plateau has been estimated by stochastic finite-fault simulation method. The corresponding acceleration time histories on rock level at several sites in the epicentral region have been computed. These results are validated by comparing them with the estimates obtained from Medvedev–Sponheuer–Karnik (MSK) intensity observations of 1897 Shillong earthquake. Using the local soil parameters, the simulated rock level acceleration time history at Guwahati city is further amplified up to the ground surface by nonlinear site response analysis. The results obtained are presented in the form of peak ground acceleration (PGA) contour map. The maximum amplification for PGA over Guwahati city is as high as 2.5. Based on the simulated PGA, the liquefaction susceptibility at several locations in the city has been estimated. The results are presented in the form of contours of factor of safety against liquefaction at different depths below the ground surface. It is observed that over a large part of the Guwahati city, the factor of safety against liquefaction is less than one, indicating that the city is highly vulnerable to liquefaction in the event of this earthquake. The contour maps obtained can be used in identifying vulnerable areas and disaster mitigation.  相似文献   

10.
The town of Edessa is located on Northern Greece at a region that is characterized as low seismicity zone due to the fact that few moderate events of M < 6 occurred during the last century. According to the Greek Seismic Code, the expected acceleration having a 10% probability of being exceeded in 50 years is equal to 0.16g. However, an amplification of ground motion is likely to occur due the local geology that is consisted of Holocene fluvio-torrential deposits. The basic aim of this paper is to evaluate the site amplification due to geological conditions and to assess the liquefaction hazard. In order to achieve this, 1-D site response analyses were performed. The data that were employed for the construction of the numerical models have been collected from borings with standard penetrations tests (SPT) that were drilled for construction purposes. Afterward, the liquefaction potential of the subsoil layers was evaluated taking into consideration two seismic scenarios. The first scenario was based on the seismic parameters, earthquake magnitude and PGA, assigned by the Greek Seismic Code. On the second seismic model, we employed the values of acceleration, resulted from the 1-D analyses and the earthquake magnitude as it was defined by the Greek Seismic Code. In order to compile the liquefaction hazard maps, we initially estimated the liquefaction potential index (LPI) of the soil columns using the parameters provided by SPT, for both seismic loadings, and afterward we correlated these values with the proposed classification of the severity of liquefaction-induced deformations. In addition, having computed the value of probability based on the LPI, liquefaction manifestations probability maps were compiled for both scenarios. The result of this study was that liquefaction-induced ground disruptions are likely to occur at the center of the city, among the branches of Voda River, only when the amplified values of acceleration are taken into account to the computation of liquefaction potential.  相似文献   

11.
This study presents results of both field and laboratory tests that have been used to asses liquefaction susceptibilities of the soils in Yalova city, located in the well-known seismically active North Anatolian Fault Zone. Liquefaction potentials of the sub-surface materials in Yalova city were estimated by using the standard penetration test (SPT) method of field testing. The data obtained have been mapped according to susceptibility, and the susceptibility maps based on the geotechnical data indicated a moderate to high susceptibility to liquefaction for the magnitude of earthquake of M=7.4. Both the high groundwater level and the grain size of the soils, in conjunction with the active seismic features of the region, result in conditions favourable to the occurrence of liquefaction. When the surface and near surface geological conditions were taken under consideration, it was seen that the study areas geology is prone to liquefaction having a moderate liquefaction susceptibility. If geologic and geomorphological criteria are considered, it should be understood that the study area as discussed under the regions geology is susceptible to liquefaction. The geotechnical data largely support the geologic-based liquefaction susceptibility of the study area.  相似文献   

12.

The detrimental effects of an earthquake are strongly influenced by the response of soils subjected to dynamic loading. The behavior of soils under dynamic loading is governed by the dynamic soil properties such as shear wave velocity, damping characteristics and shear modulus. Worldwide, it is a common practice to obtain shear wave velocity (V s in m/s) using the correlation with field standard penetration test (SPT) N values in the absence of sophisticated dynamic field test data. In this paper, a similar but modified advanced approach has been proposed for a major metro city of eastern India, i.e., Kolkata city (latitudes 22°20′N–23°00′N and longitudes 88°04′E–88°33′E), to obtain shear wave velocity profile and soil site classification using regression and sensitivity analyses. Extensive geotechnical borehole data from 434 boreholes located across 75 sites in the city area of 185 km2 and laboratory test data providing information on the thickness of subsoil strata, SPT N values, consistency indices and percentage of fines are collected and analyzed thoroughly. A correlation between shear wave velocity (V s) and SPT N value for various soil profiles of Kolkata city has been established by using power model of nonlinear regression analysis and compared with existing correlations for other Indian cities. The present correlations, having regression coefficients (R 2) in excess of 0.96, indicated good prediction capability. Sensitivity analysis predicts that significant influence of soil type exists in determining V s values, for example, typical silty sand shows 30.4 % increase in magnitude of V s as compared to silt of Kolkata city. Moreover, the soil site classification shows Class D and Class E category of soil that exists typically in Kolkata city as per NEHRP (Recommended provisions for seismic regulations for new buildings and other structures—Part 1: Provisions. Prepared by the Building Seismic Safety Council for the Federal Emergency Management Agency (Report FEMA 450), Washington, DC, 2003) guidelines and thereby highlighting the seismic vulnerability of the city. The results presented in this study can be utilized for seismic microzonation, ground response analysis and hazard assessment for Kolkata city.

  相似文献   

13.
Yalova City (Turkey) is in a tectonically active location that is particularly affected by the northern branch of the North Anatolian Fault Zone. Magnitudes 7.4 and 7.2 earthquakes in 1999 caused great destruction in Yalova. The heavy damage to buildings and other civil engineering structures was mainly due to liquefaction-induced settlement and site effects such as resonance and amplification. In the first phase of this study, the soil liquefaction potential index (PL) and the induced soil settlement were estimated. In the second phase, the effects on sites in Yalova soil were investigated using microtremor and earthquake data. The fundamental periods and amplification in soft soil were compared with microtremor data and strong ground motion records obtained by a local array of eight accelerograph stations deployed in Yalova. Thirty-seven ‘single site’ ambient noise measurements were taken in a dense grid of points covering the centre of the city. A comparison between fundamental periods obtained from strong ground motion records and from microtremor measurements showed similarities, in the 0.1–5 Hz range. Finally, soil liquefaction and amplification (or resonance) were divided into regions according to the extent of damage and the geotechnical/geophysical results.  相似文献   

14.
The lack of earthquake-induced liquefaction features in Late Wisconsin and Holocene sediments in Genesee, Wyoming, and Allegany Counties suggests that the Clarendon–Linden fault system (CLF) did not generate large, moment magnitude, M≥6 earthquakes during the past 12,000 years. Given that it was the likely source of the 1929 M 4.9 Attica earthquake, however, the Clarenden–Linden fault system probably is capable of producing future M5 events. During this study, we reviewed newspaper accounts of the 1929 Attica earthquake, searched for earthquake-induced liquefaction features in sand and gravel pits and along tens of kilometers of river cutbanks, evaluated numerous soft-sediment deformation structures, compiled geotechnical data and performed liquefaction potential analysis of saturated sandy sediments. We found that the 1929 M 4.9 Attica earthquake probably did not induce liquefaction in its epicentral area and may have been generated by the western branch of the Clarendon–Linden fault system. Most soft-sediment deformation structures found during reconnaissance did not resemble earthquake-induced liquefaction features, and even the few that did could be attributed to non-seismic processes. Our analysis suggests that the magnitude threshold for liquefaction is between M 5.2 and 6, that a large (M≥6) earthquake would liquefy sediments at many sites in the area, and that a moderate earthquake (M 5–5.9) would liquefy sediments at some sites but perhaps not at enough sites to have been found during reconnaissance. We conclude that the Clarendon–Linden fault system could have produced small and moderate earthquakes, but probably not large events, during the Late Wisconsin and Holocene.  相似文献   

15.
2016年11月25日新疆阿克陶县木吉乡发生MS6.7地震,发震构造为公格尔山拉张系北端的木吉断裂,断裂总长度超过100 km,以右旋走滑为主兼有一定的拉张分量。文章在对震区进行了初步的地震地质灾害调查,总结砂土液化和地裂缝在高原季节性冻土地区的分布及发育特点的基础上,发现:1)在研究区Ⅰ维日麻村的砂土液化主要沿原有泉眼或沿地裂缝发育,沿泉眼形成的砂土液化其喷砂锥的覆盖面积达36.1 m2,占总液化面积的60%,研究区Ⅱ布拉克村的砂土液化则主要是沿草甸的根系喷出,在地表形成大面积的最新涌水结冻特征;2)对研究区Ⅱ布拉克村地裂缝的深度进行统计,反演出区域冻土层厚度,结合探槽揭露的地层剖面,推断冻土层发生大面积地裂缝是因为地震引起冻土层下部融土层发生砂土液化导致土层变形失稳,从而使冻土层发生形变产生一系列规律性的地裂缝。  相似文献   

16.
The Kocaeli earthquake (M w = 7.4) of 17 August 1999 occurred in the Eastern Marmara Region of Turkey along the North Anadolu Fault and resulted in a very serious loss of life and property. One of the most important geotechnical issues of this event was the permanent ground deformations because of both liquefaction and faulting. These deformations occurred particularly along the southern shores of ?zmit Bay and Sapanca Lake between the cities of Yalova and Adapazar? in the west and east, respectively. In this study, three sites founded on delta fans, namely De?irmendere Nose, Yeniköy tea garden at Seymen on the coast of ?zmit Bay, and Vak?f Hotel site on the coast of Sapanca Lake were selected as typical cases. The main causes of the ground deformations at these sites were then investigated. Geotechnical characterization of the ground, derivation of displacement vectors from the pre- and post-earthquake aerial photographs, liquefaction assessments based on field performance data, and analyses carried out using the sliding body method have been fundamental in this study. The displacement vectors determined from photogrammetric evaluations conducted at De?irmendere and Seymen showed a combined movement of faulting and liquefaction. But except the movements in the close vicinity of shorelines, the dominant factor in this movement was faulting. The results obtained from the analyses suggested that the ground failure at De?irmendere was a submarine landslide mainly because of earthquake shaking rather than liquefaction. On the other hand, the ground failures at the Yeniköy tea garden on the coast of Seymen and the hotel area in Sapanca town resulted from liquefaction-induced lateral spreading. It was also obtained that the ground deformations estimated from the sliding body method were quite close to those measured by aerial photogrammetry technique.  相似文献   

17.
The Niumiangou landslide (~7.5 × 106 m3) was the largest that occurred in the town of Yingxiu (the epicentral area) during the 2008 Wenchuan earthquake. This landslide originated on a steep slope (~30°) that was located directly above the rupture surface of the responsible fault and then traveled ~2 km after flowing down the axes of two gently sloping (<12°) valleys. Evidence at the site indicates that the landslide materials were highly fluidized and underwent rapid movement. To examine the initiation and movement mechanisms of this landslide, we performed a detailed field survey, conducted laboratory tests on samples taken from the field, and analyzed the seismic motion. We conclude that the landside materials were displaced due to seismic loading during the earthquake and that liquefaction may have been triggered in saturated layers above the sliding surface with progressive downslope sliding, which resulted in the high mobility of the displaced materials. The liquefaction of colluvial deposits along the travel path due to loading by the sliding mass enhanced the mobility of the displaced mass originating in the source area. Using an energy-based approach, we estimated the dissipated energy in our cyclic loading test and the possible energy dissipated to the soil layer on the slope by the earthquake. We infer that the seismic energy available for the initiation of the slope failure in the source area may have greatly exceeded the amount required for the initiation of the liquefaction failure. The slope instability might have been triggered several seconds after the arrival of seismic motion.  相似文献   

18.
以标贯试验为依据的砂土液化确定性及概率判别法   总被引：1，自引：0，他引：1  
核电厂址非基岩场地的地基液化问题是核电厂选址的关键问题,亟需建立核电厂址地基液化判别方法。回顾了以标贯试验和地表峰值加速度为依据的砂土液化判别方法的演化历史,依据Idriss-Boulanger确定液化临界曲线的基本方法,提出了确定液化临界曲线的基本原则,分别依据美国液化数据库、中国抗震规范液化判别式所用的液化数据及综合两者的液化数据资料,给出了相应的液化临界曲线,验证了液化临界曲线的位置对不同的细粒含量、有效上覆压力、现场试验方法的液化数据的合理性,分析了测量或估计土层循环应力比和修正标贯击数各种因素的不确定性对液化临界曲线的敏感性,结果表明：所提的液化临界曲线不易受各种因素的影响。利用Monte Carlo模拟、加权最大似然法和加权经验概率法,给出了液化临界曲线的名义抗液化安全系数与液化概率的经验关系式及概率等值线,并对核电厂Ⅰ类、Ⅱ类和Ⅲ类抗震物项地基,给出了相应的液化临界曲线。  相似文献   

19.
Antakya city is at risk because of strong earthquakes occurring in the area, and different soil conditions that can produce variation of the ground motion amplification. Microzonation of cities provides a basis for site-specific hazard analysis in urban settlements. In particular, seismic microzonation can be provided by means of detailed seismic assessment of the area, including earthquake recordings and geological studies. In this paper, we propose a preliminary microzonation map for the city of Antakya, based on the variation of the dominant periods and shear velocities of the sediments covering the area. The periods are retrieved from microtremor measurements conducted at 69 sites, using the horizontal-to-vertical spectral ratio technique. The results of microtremor analysis were compared with data obtained from refraction microtremor (ReMi) measurements at four profiles crossing the studied area. According to the classification of dominant periods, Antakya city can be divided into five zones, probably prone to different levels of seismic hazard. The shorter natural periods are in inner Antakya and both the sides of Asi River (i.e., northern and southern parts). The eastern and western parts of Antakya have maximum dominant periods. The V s 30 values were calculated by using the ReMi method along the profiles. Antakya city has V s 30 values in the range of category C of the national earthquake hazard reduction programme site classification.  相似文献   

20.
Bouckovalas  G.D.  Kouretzis  G.P.  Kalogeras  I.S. 《Natural Hazards》2002,27(1-2):105-131
The strong ground motion from Athens, Greece 07/09/1999 earthquake has been recorded by eighteen (18) stations, fourteen (14) within the central Athens area and four (4) at the centers of nearby towns. The ground conditions for most of the recording sites were identified, based on previous geotechnical investigations carried out in the wider area of the sites, and consequently correlated to the seismic motion characteristics. Hence, it has been possible to evaluate the accuracy of different seismological methods for site characterization and also estimate soil effects on peak ground acceleration and elastic response spectra. In addition, preliminary estimates are drawn for the seismic motion characteristics at the epicentral area, where no strong motion recordings are available. The detailed soil profiles at the recordingsites are placed in the Appendix.  相似文献   

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