Showing 4 results for Sharifi
J. Sharifi, M. R. Nikodel,
Volume 9, Issue 3 (12-2015)
Abstract
In this research, prediction of concrete strength containing different aggregates using Non-destructive (Ultrasonic) testing through Artificial Neural Networks was carried out. For this purpose, aggregates with different properties were selected from the quarries, and then their destructive and nondestructive properties were obtained in laboratory. The significance of this research, using different aggregates with physical, mechanical and chemical properties also used two different test methods, such as Non-destructive static and dynamic testing, which are respectively uniaxial compressive strength and compressive wave velocity. Thus, this model includes various types of samples and the prediction model includes static and dynamic tests. The results showed that the use of artificial neural networks not only increases the accuracy, but also it reduces costs and time.
Mehri Sharifi, Maryam Meftahi, Seyed Abolhasan Naeini,
Volume 12, Issue 5 (English article specials 2018)
Abstract
Materials such as waste tire chips were widely used to improve the strength of soil. The objective of this study is to discuss the residual strength or steady-state behavior of sand-waste tire chip mixtures. A series of undrained monotonic triaxial compression tests were conducted on reconstituted saturated specimens of sand and sand-tire chip mixtures with variation in the tire-chip contents from 0 to 4 percentages by dry weight of soil. The specimens are prepared using dry deposition method of preparation. The influence on residual resistance of varying confining pressure (100, 200, and 300 kPa) and sand mixture relative density (40, 65, and 80%) were evaluated. Tests results showed that by increasing the tire chip contents, the residual strength increased and steady-state lines move to the right of log Sus-e diagram. Also, the residual resistance improvement induced by tire chip inclusions was found to be sensitive to the relative density of samples and applied confining pressure.
Mohammad Sadegh Sharifi, Saeed Zarei, Seyed Reza Mansouri, Abdullah Hussaini,
Volume 19, Issue 4 (Winter 2025)
Abstract
The active tectonics of eastern Iran, resulting from the convergence of the Arabian and Eurasian plates and numerous active faults, has caused high stress concentration, as evidenced by major historical earthquakes such as those in Tabas (1978) and Bam (2003). This study aims to conduct a fractal analysis of seismicity parameters and investigate crustal stress heterogeneity in eastern Iran. To this end, an earthquake dataset of historical and instrumental events with Mw ≥ 4 (1900–2024) was compiled from the ISC and NEIC databases. After filtering and declustering, the data were analyzed using ZMAP and ArcGIS. The b-value (an indicator of stress level and the probability of large earthquakes), the D-value (the geometrical complexity of faulting), and the D/b ratio were calculated simultaneously and mapped spatially. The results show that the b-value ranges from 0.8 to 1.1, and the D-value ranges from approximately 1.6 to 2.3. Regions with low b-values and high D-values, especially along the Nehbandan and Dasht-e Bayaz faults, indicate high stress concentrations and an elevated likelihood of larger earthquakes. The total seismic moment of the cataloged earthquakes is estimated at 3.5×10²³ N·m, yielding an average annual seismic moment rate of 2.7×10¹⁶ N·m/yr (calculated by averaging over the available catalog years). The D/b ratio, regarded as an index of stored energy and stress heterogeneity, exceeds two in these zones and exhibits a strong correlation with areas of a high rate of seismic moment release. This pattern implies that an increase in fault geometrical complexity coupled with a decrease in the b-value signals the crust’s approach to the rupture threshold. Thus, by emphasizing the significance of the D/b ratio, the present findings offer a quantitative approach to mapping stress states, fault structures, and the potential for significant earthquakes in eastern Iran.
Faeze Samadpoor, Morteza Mozafari, Majid Dashti Barmaki, Parisa Sharifi,
Volume 19, Issue 4 (Winter 2025)
Abstract
Groundwater plays a vital role in meeting the drinking and agricultural water needs of Kermanshah Plain. In order to protect the aquifer, it is important to evaluate its sustainability in the face of current and future demands and stresses. Groundwater sustainability indicators help ensure the sustainable management of these resources. This research aims to evaluate the sustainability of groundwater resources in the Kermanshah Plain using various indicators. To this end, AHP analysis was used to evaluate the sustainability indicator of this aquifer based on nine indicators in five quantitative, qualitative, environmental, social, and political sectors. First, the value of each indicator was calculated, and then its sustainability was evaluated using data transferred to GIS software and interpolation. Next, the weight and rank of each indicator and category were calculated to prepare an index-equivalent map. Then, using weighted overlap, the final sustainability map was obtained. Finally, the Receiver Operating Characteristic (ROC) curve was used to measure the accuracy of the results. The prepared sustainability map shows that indicators of groundwater storage changes and quality conditions are among the most important factors affecting the sustainability of the plain's groundwater resources. The results also show that the sustainability situation is weaker in the central areas and more favorable in the border areas (river headwaters) and southeast of the aquifer. To improve the sustainability of the region's groundwater resources, it is recommended that new water management policies be adopted with the participation of the people and based on scientific, principled solutions.
