Erratum to: Hydrogeological investigations of thermal waters in the Sfax Basin (Tunisia)     

Badia Chulli  Aysen Davraz  Jalila Makni  Mourad Bedir  Hamed Ben Dhia 《Environmental Earth Sciences》2012,66(3):993

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Empirical seismic vulnerability analysis for masonry buildings based on school buildings survey in Iran     

Hamed Azizi-Bondarabadi  Nuno Mendes  Paulo B. Lourenço  Neda H. Sadeghi 《Bulletin of Earthquake Engineering》2016,14(11):3195-3229

School facilities in Iran, in particular masonry schools, have shown poor performance during past earthquakes and can be identified as one of the parts of the country’s infrastructure that is most vulnerable to earthquakes. Hence, in this paper a method to perform index-based damage assessment for brick masonry schools located in the province of Yazd, the central region of Iran, using a comprehensive database of school buildings, is proposed. The database was obtained from the field survey forms applied for each observed school to collect the features of and damage to the structure. The results of a vulnerability index method developed in Iran are employed as input data to obtain empirical fragility curves for the school inventory. The Macroseismic model and GNDT II level method are two empirical methods combined in this procedure. Finally, the procedure is verified using damage survey data obtained after recent earthquakes (1990 Manjil–Rudbar earthquake and 2003 Bam earthquake) that occurred in Iran.  相似文献   

Influence of the construction process and nonstructural components on the modal properties of a five‐story building          下载免费PDF全文

Rodrigo Astroza  Hamed Ebrahimian  Joel P. Conte  José I. Restrepo  Tara C. Hutchinson 《地震工程与结构动力学》2016,45(7):1063-1084

A full‐scale five‐story reinforced concrete building was built and tested on the NEES‐UCSD shake table during the period from May 2011 to May 2012. The purpose of this test program was to study the response of the structure and nonstructural components and systems (NCSs) and their dynamic interaction during seismic base excitation of different intensities. The building specimen was tested first under a base‐isolated condition and then under a fixed‐based condition. As the building was being erected, an accelerometer array was deployed on the specimen to study the evolution of its modal parameters during the construction process and placement of major NCSs. A sequence of dynamic tests, including daily ambient vibration, shock (free vibration) and forced vibration tests (low‐amplitude white noise and seismic base excitations), were performed on the building at different stages of construction. Different state‐of‐the‐art system identification methods, including three output‐only and two input‐output methods, were used to estimate the modal properties of the building. The obtained results allow to investigate in detail the effects of the construction process and NCSs on the dynamic parameters of this building system and to compare the modal properties obtained from different methods, as well as the performance of these methods. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

Piles shaft capacity from CPT and CPTu data by polynomial neural networks and genetic algorithms     

H. Ardalan  A. Eslami  N. Nariman-Zadeh 《Computers and Geotechnics》2009

Cone penetration test (CPT) is one of the most common in situ tests which is used for pile design because it can be realized as a model pile. The measured cone resistance (q_c) and sleeve friction (f_s) usually are employed for estimation of pile unit toe and shaft resistances, respectively. Thirty three pile case histories have been compiled including static loading tests performed in uplift, or in push with separation of shaft and toe resistances at sites which comprise CPT or CPTu sounding. Group method of data handling (GMDH) type neural networks optimized using genetic algorithms (GAs) are used to model the effects of effective cone point resistance (q_E) and cone sleeve friction (f_s) as input parameters on pile unit shaft resistance, applying some experimentally obtained training and test data. Sensitivity analysis of the obtained model has been carried out to study the influence of input parameters on model output. Some graphs have been derived from sensitivity analysis to estimate pile unit shaft resistance based on q_E and f_s. The performance of the proposed method has been compared with the other CPT and CPTu direct methods and referenced to measured piles shaft capacity. The results demonstrate that appreciable improvement in prediction of pile shaft capacity has been achieved.  相似文献   

GIS-based evaluation of groundwater quality and estimation of soil salinization and land degradation risks in an arid Mediterranean site (SW Tunisia)     

Besser  Houda  Mokadem  Naziha  Redhouania  Belgacem  Rhimi  Nacira  Khlifi  Faten  Ayadi  Yosra  Omar  Zohra  Bouajila  Abdelhakim  Hamed  Younes 《Arabian Journal of Geosciences》2017,10(16):1-18

Arabian Journal of Geosciences - The present work is concerned with the valorization of clay minerals of the Aleg formation (Coniacian-middle Campanian) in the clinker manufacturing. The studied...  相似文献   

Bearing Capacity Factors of Ring Footings by Using the Method of Characteristics     

Hamed Gholami  Ehsan Seyedi Hosseininia 《Geotechnical and Geological Engineering》2017,35(5):2137-2146

Ring footings can be more effective and economical than circular footings. In spite of similarities between circular and ring footings, their behaviors are different in some respects such as bearing pressure distribution under the footing and settlement. But no exclusive theoretical prediction of ultimate bearing capacity has been reported for ring footings. In the present study, stress characteristics method is employed for coding the bearing capacity of ring footing with horizontal ground surface. In the calculations, friction at the contact between the soil and foundation is considered. In this research, the soil obeys the Mohr–Coulomb yield criterion and that is cohesive–frictional-weighted with applied surcharge pressure. The bearing capacity factors Nγ, Nq and Nc for ring footings were calculated by a written code based on the method of characteristics. Bearing capacity was determined for different conditions of soil and different ratio of radii in comparison with the principle of superposition results. The findings show that the principle of superposition is effective for determining the bearing capacity of a ring footing.  相似文献   

Review Paper: Post-stack 4D seismic time-shifts: Interpretation and evaluation     

Colin MacBeth  Maria-Daphne Mangriotis  Hamed Amini 《Geophysical Prospecting》2019,67(1):3-31

A review and analysis of post-stack time-lapse time-shifts has been carried out that covers published literature supplemented by in-house datasets available to the authors. Time-shift data are classified into those originating from geomechanical effects and those due to fluid saturation changes. From these data, conclusions are drawn regarding the effectiveness of post-stack time-shifts for overburden and reservoir monitoring purposes. A variety of field examples are shown that display the range and magnitude of variation for each class of application. The underlying physical mechanisms creating these time-shifts are then described, and linked to a series of generic and field-specific rock physics calculations that predict their magnitudes. These calculations serve as a guide for practitioners wishing to utilize this information on their own datasets. Conclusions are drawn regarding the reliability of this attribute for monitoring purposes, and the extent to which further development is required and how it should be reported by authors.  相似文献   

A comparative study of support vector machines and artificial neural networks for predicting precipitation in Iran     

Omid Hamidi  Jalal Poorolajal  Majid Sadeghifar  Hamed Abbasi  Zohreh Maryanaji  Hamid Reza Faridi  Lily Tapak 《Theoretical and Applied Climatology》2015,119(3-4):723-731

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Multi-sensor approach to settlement analysis of earth dams   总被引：1，自引：0，他引：1  

Alireza A. Ardalan  Marzieh Jafari 《Computational Geosciences》2012,16(1):123-138

In this paper, a fusion method for the settlement study of the earth dams based on geodetic and geotechnical data is developed. The developed method can be algorithmically explained as follows: (a) interpolation of the geotechnical data to the epoch of geodetic observations by four degree polynomial fitting, which serves as a low-pass filter. (b) Conversion of the initial observations into time series of the dam heights at the geodetic and geotechnical stations. (c) Fusion of the data from the two sources at different fusion levels. (d) Final decision based on the deformation parameters derived from fused data. The significant innovation of the proposed method centered upon its ability to incorporate geodetic and geotechnical observation types into a one integrated solution through fusion. The method is numerically tested for the Karkhe earth dam by using geodetic and geotechnical data from 1997 till 2009. The numerical evaluation at 229 check points indicates more than 70% improvement in the settlementmodeling based on the fusion of the geodetic and geotechnical data, as compared to the settlement modeling based on geotechnical data alone.  相似文献   

Curie point depth beneath the Barramiya–Red Sea coast area estimated from aeromagnetic spectral analysis     

Sami Hamed Abd El Nabi 《Arabian Journal of Geosciences》2012,5(6):1209-1221

The geothermal structure beneath of the Barramiya?CRed Sea coast area of the Central Eastern Desert of Egypt has been determined using Curie point depth (CPD), which is temperature-dependent. The CPD and the surface heat flow (q) maps of such area are estimated by analyzing aeromagnetic data. Such data are low-pass-filtered and analyzed to estimate the magnetic bottom using the centroid method. The heat flow map reflects the geothermic nature of the region. However, it is suggested that the shallow Curie point temperature depth pattern depends on the tectonic regime and morphology, which continues eastwards through the Red Sea. Particularly, the coastal regions are characterized by high heat flow (83.6?mW/m²) and shallow Curie depth (22.5?km), whereas the western portion of the studied area has a lower heat flow (<50?mW/m²) and deeper Curie depth (~40?km). In addition to its bordering to the Red Sea margin, such high heat flow anomaly is associated with the increased earthquake swarms activity in the Abu Dabbab area. El-Hady (1993) attributed the swarm activity to the geothermal evolution. Also, the heat flow pattern is correlatable by the numerous results of shallow borehole temperature measurements as reported by Morgan and Swanberg (1979). A significant low heat flow extending in the northeast?Csouthwest direction, which is associated with NE?CSW large areal extent negative Bouguer gravity anomaly and NE/SW-trending belt of the deep CPD region, seems to be directly related to the surface outcrops of Precambrian older granitoids of the mountainous range of that trend.  相似文献