Showing 245 results for Type of Study: Original Research
Mis Tahereh Daniyalnezad, Dr Aliakbar Momeni,
Volume 19, Issue 3 (12-2025)
Abstract
Following an unusual period of rainfall period at the end of the previous winter, several landslides occurred in Tolubin village in early spring 2019. These landslides resulted in the destruction of 12 houses as well as causingdamage to roads and gas transmission lines. This this research was therefore conducted to investigate the mechanism of these landslides. The study was comprised four main phases: a literature review, field investigations, laboratory studies, and a slope stability assessment using Slide 6.20 software. During the field surveys, landslide-prone profiles were identified, and both disturbed and undisturbed samples were collected. The disturbed samples were used for laboratory tests, including determining the grain size distribution, calculating the Atterberg limits, performing calcimetry, conducting X-ray diffraction (XRD) analysis, and carrying out scanning electron microscopy (SEM) analysis. Additionally, 27 undisturbed samples were prepared for direct shear tests under varying moisture conditions. Finally, stability analyses of the studied profiles were performed in Slide software under different moisture conditions, considering both static and quasi-static states, based on the geometric characteristics of the slopes and shear strength parameters (internal friction angle and cohesion).. The obtained safety factors indicated that all slopes were on the threshold of failure under saturated static conditions and would certainly fail under saturated quasi-static conditions. In conclusion, the high sensitivity of the slope’s marly materials to moisture variations and the unusual rainfall in February and March 2019 were identified as the primary factors contributing to these landslides.
Soroush Mahdavian, Ali Raeesi Estabragh, Shima Azadeh Ranjbar,
Volume 19, Issue 3 (12-2025)
Abstract
This research study investigated the impact of dimethyl phthalate (DMP) on the physical and mechanical properties of clay soil through experimental testing. Additionally, the impact of hydrated lime and magnesium oxide on improving the properties of clay soil was investigated. The contaminated soil was artificially produced in the laboratory. Natural and contaminated soils were mixed with the above agents at percentages of 5.0%, 10.0% and 15.0%, respectively. The experimental test programme for this study comprised: Atterberg limits, compaction, uniaxial compression tests (UCS) and scanning electron microscopy (SEM). Samples for the UCS tests, both with and without additives, were prepared using the static compaction method and tested at curing times of 7, 14 and 28 days. The results showed that, in general, the Atterberg limit, compaction parameter (maximum dry unit weight) and UCS values for the contaminated soil were lower than for the natural soil. The results also indicated a reduction in UCS values for a mixture of contaminated soil and 10% hydrated lime or magnesium oxide. A comparison of the final strength values of samples made from a mixture of contaminated soil and 10% hydrated lime or magnesium oxide showed that the strength was 34.4% and 63.8% lower than that of a mixture with 5% of these additives at the same curing time. The E50 values were calculated from the stress-strain curves of the different tests. Additionally, the SEM results showed that changes in the properties of the mixture prepared from these agents and natural or contaminated soil were due to a chemical reaction between the soil and the additives.
Eng. Mohammad Hossein Jowlar, Dr. Mashalah Khamehchiyan, Dr. Mohammad Reza Nikudel, Dr. Asghar Azadi,
Volume 19, Issue 3 (12-2025)
Abstract
Over the past three decades, research into the factors influencing the development of gypsum karsts has become an active and growing area of study. The mechanically weak nature of gypsum, along with its rapid dissolution and deformability, contributes to the formation of gypsum karsts, voids, and caverns in regions where gypsum deposits are present. This process can significantly undermine geotechnical stability by reducing bearing capacity and increasing settlement. This issue is particularly critical in heavy industrial settings such as petrochemical facilities, where large storage tanks and other infrastructure are founded directly on the ground surface. Consequently, identifying and assessing these processes is essential for the design, construction, and maintenance of engineering projects. This study assesses subsurface gypsum karsts within the Masjed Soleyman Petrochemical site using an integrated geophysical and geotechnical approach. Ground Penetrating Radar (GPR) was employed across 24 profiles totaling 2,307 meters, also geotechnical data were obtained from 113 boreholes drilled to depths of 20–40 meters. Following data analysis, 32 occurrences of subsurface gypsum karsts were identified at depths ranging from 4 to 36 meters. Subsequently, surface water drainage patterns were analyzed and digitized from historical Corona satellite imagery (1968). In parallel, groundwater levels and flow direction maps were generated using data from electric probe depth finder measurements in boreholes. The integration of these datasets revealed that most gypsum karsts are concentrated in areas where groundwater tends to accumulate and flow. Finally, groundwater sampling and chemical analysis revealed an average sulfate concentration of approximately 1,480 ppm, indicative of a severe sulfate exposure environment.
Reza Mohseni Afkham, Dr Mojtaba Bahaaddini, Dr Abbas Majdi,
Volume 19, Issue 3 (12-2025)
Abstract
Tensile strength is one of the most important mechanical properties of brittle materials and plays a decisive role in the stability of many civil and mining structures. The Brazilian test is the most common indirect method for determining tensile strength and is widely employed. In this test, it is generally assumed that a central tensile crack initiates and propagates along the loading axis. However, the actual fracture process in the Brazilian test remains a controversial issue, and using curved loading platens has been recommended to better concentrate tensile stresses at the center of specimen. This study investigated the influence of platen curvature on the estimated tensile strength and the fracture patterns. To this end, five types of platen with curvature ratios of 0, 0.50, 0.57, 0.67, and 0.80 were prepared. All tests were recorded using a high-speed camera to precisely capture the initiation and propagation of cracks. To minimize the effect of rock heterogeneity and obtain consistent results, synthetic specimens were used, and five samples were tested for each curvature ratio.The results indicated that increasing the platen curvature led to a higher estimated tensile strength. While the increase was negligible for curvature ratios up to 0.67, at the ratio of 0.80 the tensile strength was approximately 48% higher compared to 0.67. Analysis of fracture patterns revealed that at the curvature ratio of 0.80, the fracture mode shifted to an unstable and disturbed pattern, characterized by secondary shear cracks and the irregular propagation of the main crack.
Ms Haniye Yaghoubi, Dr. Reza Jahanshahi, Dr. Morteza Mozafari,
Volume 19, Issue 3 (12-2025)
Abstract
This study examines the hydrochemistry and contamination levels of groundwater resources in the urban area of Birjand in eastern Iran. Water quality was assessed and pollution sources were identified through sampling 22 wells, 12 qanats and 4 springs. The results showed that electrical conductivity varied from 300 to 8,000 µS/cm, while pH ranged from 7.23 to 8.71. According to the Piper diagram, the dominant hydrochemical facies were chloride, sulphate and bicarbonate types. In some of the samples, the nitrate concentration exceeded the permissible limit of 50 mg/L set by the World Health Organization, indicating the influence of urban wastewater and agricultural effluents. The ionic ratios reveal the influence of halite and gypsum dissolution processes, as well as ion exchange reactions, on the chemical composition of the water. A health risk assessment showed that, while most sources are within the safe range for adults, some wells and qanats pose a higher risk to infants and children. This study aims to provide a scientific framework for understanding the geochemical processes that control water quality, and to identify high-risk areas for the sustainable planning and management of groundwater resources in the Birjand plain.
Mohammad Sadegh Sharifi, Saeed Zarei, Seyed Reza Mansouri, Abdullah Hussaini,
Volume 19, Issue 4 (12-2025)
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.
Seyedeh Aida Mirshafiey, Asghar Milan,
Volume 19, Issue 4 (12-2025)
Abstract
As one of the key factors causing changes in the Earth's altitude, earthquakes can lead to subsidence or uplift in different areas. These changes are mainly caused by the displacement of tectonic plates, movement along faults and changes in pressure deep within the Earth. The type of fault and the conditions of the earthquake determine whether uplift or subsidence occurs. Monitoring and examining these changes is of great importance for crisis management and relief, improving urban planning, and reducing environmental damage. To study changes in the Earth's surface, various methods are used, including accurate alignment, global positioning systems, laser scanning, and remote sensing, each of which has a specific accuracy and characteristic. Nowadays, satellite data and remote sensing methods are an efficient tool for calculating the vertical displacement of the Earth's surface. This study investigated the potential of Sentinel-1 satellite data and images to study land surface changes due to the 5.6-magnitude Khoy earthquake using the radar differential interferometry technique. Processing the radar images before and after the earthquake allowed us to extract the vertical displacements of the phase changes. The results show uplift and subsidence occurring in some areas close to the epicentre and in more distant places. The maximum uplift was 0.08 metres and the maximum subsidence was -0.156 metres. These results demonstrate the non-uniform pattern of land surface elevation changes caused by this earthquake.
Ms Solmaz Darsanj, Dr. Mehrdad Emami Tbrizi, Dr. Hassan Afshin,
Volume 19, Issue 4 (12-2025)
Abstract
Aeolian sands in arid and semi-arid regions are considered problematic due to their loose structure, low bearing capacity and difficulty in compacting them. Iran's dry climate and phenomena such as the desiccation of Lake Urmia have exacerbated the dispersion of saline sands. One common approach to mitigating these issues is chemical stabilization using additives such as cement. This study investigates the effect of stabilizing saline aeolian sands collected from the Lake Urmia basin using Type I Portland cement. Stabilized soil specimens with varying levels of salinity and cement content were prepared and subjected to unconfined compressive strength testing after a 7-day curing period. The results showed that increasing the cement content significantly improves compressive strength. Furthermore, the presence of salt in the soil samples did not hinder the stabilization process, but instead contributed to improved strength in the short term. These findings highlight the importance of considering the type and concentration of salts when designing stabilization treatments for saline granular soils in arid and semi-arid climates.
Younes Mousavi, Mohammad Nakhaei, Gholamhossein Karami,
Volume 19, Issue 4 (12-2025)
Abstract
Planning the management and optimized consumption of groundwater resources is a critical infrastructural necessity, as these resources supply a significant portion of the country's drinking water. A key component of this planning is accurately calculating the water balance, which requires determining the aquifer's hydrodynamic parameters, including transmissivity (T) and hydraulic conductivity (K). This study calculated these parameters using step-drawdown pumping test data from a single-well system across various locations in the 411-square-kilometer Hashtgerd Plain aquifer (an unconfined aquifer) with AquiferWin32 software. The results indicate that transmissivity is distributed unevenly across the plain. The lowest transmissivity values were observed in the southern (Kourosh Town) and southwestern (Najmabad) sectors, while the highest values were associated with the Kordan alluvial fan and its downstream lands. Based on these findings, maximum transmissivity was estimated at 3,682 square meters per day, with an average of 440 square meters per day. Hydraulic conductivity was determined by integrating saturated thickness data from geoelectrical studies with the previously calculated transmissivity values. The final results showed that hydraulic conductivity ranges from a minimum of 0.2 meters per day in the southern regions to a maximum of 9.7 meters per day in the central aquifer.
Faeze Samadpoor, Morteza Mozafari, Majid Dashti Barmaki, Parisa Sharifi,
Volume 19, Issue 4 (12-2025)
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.
Dr Seyed Ali Asghari Pari,
Volume 19, Issue 5 (12-2025)
Abstract
This study investigates the effect of Soil-Water Characteristic Curve (SWCC) parameters on the slope stability of an earth dam under steady-state and rapid drawdown conditions. Given the importance of unsaturated soil behavior in earth dams, this research employs principles of unsaturated soil mechanics to analyze the influence of SWCC parameters on water flow rate and slope stability.The results indicate that parameters a and n positively enhance the flow rate, while an increase in parameter m reduces it. In slope stability analysis, parameters of SWCC showed negligible effects on the downstream slope stability, whereas an increase in m caused a slight reduction in the safety factor. Under rapid drawdown conditions, all parameters initially led to a decrease in the safety factor, but stability was restored after 10 days. Additionally, accounting for the unsaturated unit weight of the soil improved the safety factor in both steady-state and rapid drawdown scenarios. These findings highlight the critical role of unsaturated soil conditions in the design and stability analysis of earth dams.
Prof Seyyed Mahmoud Fatemi Aghda, Dr Asieh Hamidi, Ms Fatemeh Amiri,
Volume 19, Issue 5 (12-2025)
Abstract
The evaluation of mechanical strength, particularly the uniaxial compressive strength (UCS) of rocks, plays a critical role in the design and performance prediction of surface and underground structures, significantly impacting project costs and safety in engineering applications. Traditional laboratory testing methods for UCS assessment are destructive, time-consuming, and expensive, while indirect methods often lack reliability due to rock heterogeneity. This study addresses these limitations by developing advanced machine learning frameworks that integrate petrographic features with conventional rock properties to predict UCS and quantify associated uncertainties. The research utilized a comprehensive dataset from sedimentary rocks collected along Iran's southern coastlines (Persian Gulf and Gulf of Oman), encompassing mechanical properties (UCS, Brazilian tensile strength, point load index, porosity, ultrasonic pulse velocity), durability indices (Los Angeles abrasion, slake durability, aggregate impact value), and detailed petrographic characteristics derived from thin-section analysis. Three complementary approaches were implemented: (1) hybrid Neural Network-Gradient Boosting regression (ANN-GBR), (2) AutoML-optimized Random Forest, and (3) Monte Carlo simulation-based uncertainty quantification. Key petrographic features including immature and mature clastic textures, the mineral composition (quartz, chert) were used as input parameters alongside alongside laboratory testing to improve the prediction of UCS.The influence of these petrographic features on the rock’s microstructure and microcrack propagation contributes to reducing model uncertainty and enhances the reliability of predictions in complex and heterogeneous rock conditions. The AutoML-optimized Random Forest model demonstrated exceptional predictive performance with R² = 0.9884, RMSE = 0.5732 MPa, and MAPE = 3.6%, significantly outperforming traditional empirical methods. The ANN-GBR hybrid approach achieved R² = 0.9412 with RMSE = 1.385 MPa, while Monte Carlo simulations provided robust probabilistic assessments through 95% confidence intervals and systematic bias identification. Feature importance analysis revealed that soundness parameters and mineralogical composition are the most influentialpredictors, emphasizing the critical role of micro-scale petrographic properties in determining macroscopic mechanical behavior.
Dr Emad Namavar,
Volume 19, Issue 5 (12-2025)
Abstract
Accurate geotechnical classification is essential for designing excavations in urban environments, where soil behavior is greatly affected by excavation-induced stresses. This study improves the geotechnical characterization of fine-grained alluvial deposits belonging to the youngest sedimentary unit (Unit D) in Rieben’s classification system. A comprehensive investigation was conducted through borehole drilling, Standard Penetration Tests (SPT), pressuremeter testing, and laboratory experiments including triaxial, uniaxial, and direct shear tests. Excavation stability was evaluated using the Morgenstern–Price method under both short-term and long-term conditions. Based on the geotechnical parameters and slope stability simulations, Unit D was subdivided into three distinct zones (D1, D2, and D3) with different excavation behaviors. Zone D1, characterized by lower sand content, allows deeper vertical cuts, whereas the presence of sandy lenses in Zone D3 restricts excavation depth and requires gentler slopes. The findings provide an updated geotechnical classification framework for fine-grained alluvia, offering practical guidelines for safe excavation design and contributing to the broader understanding of alluvial systems in urban geotechnical engineering.
Dr Seyed Mahmoud Fatemi Aghda, Dr Mehdi Talkhablou, Habibolah Heidari,
Volume 19, Issue 5 (12-2025)
Abstract
Reliable assessment methods are required for designing initial support for tunnels in complex geological conditions. This study provides a thorough comparison of the Rock Mass Rating (RMR) and Rock Engineering System (RES) frameworks, examining a substantial dataset comprising 38 tunnels situated in various lithological and tectonic zones across Iran. While the RMR framework offers empirical simplicity, the RES framework provides a systems-based approach that quantifies parameter interdependencies. Analysis of field data, including shotcrete thickness and bolt density, revealed that the RES framework captures hydro-mechanical coupling more effectively, particularly in intermediate rock masses. To reconcile discrepancies between the two systems, we explored an integrated statistical formulation combining normalized RMR ratings with RES stability indices. This approach demonstrated a significantly higher correlation with field performance (R² ≈ 0.99) than the individual methods. The results emphasise the importance of integrating empirical and systems-based approaches to improve the reliability of predictions in tunnel support design and provide a solid foundation for engineering decisions in heterogeneous rock masses.
Dr Ali Ghanbari, Dr Mohammad Nakhaee, Dr Saeed Kalani, Dr Hamidreza Azizi,
Volume 20, Issue 1 (6-2026)
Abstract
Land subsidence is a complex geotechnical hazard with profound impacts on environmental stability, infrastructure resilience, and socio-economic security. This research presents a systematic field-based assessment of subsidence manifestations across the Hashtgerd, Eshtehard, and Karaj plains in Alborz Province, based on extensive surveys conducted in spring and summer of 2025. Diagnostic indicators, including extensional and compressional ground fissures, localized structural deformations, wellhead displacements, large-scale surface cracks, and variations in groundwater levels, were systematically documented. The Hashtgerd plain, particularly the Saeidabad, Sepehr, and Najmabad areas, exhibited the highest density of subsidence evidence, including progressive surface settlement, widespread fissuring, and instability of near-surface strata. In the Eshtehard plain, structural cracking in school buildings, ground ruptures adjacent to transmission towers, and retaining wall failures were frequently observed. Deep surface fissures were also identified in the Fathabad region, which is located between Eshtehard and Buin Zahra. In contrast, despite significant groundwater withdrawal, field surveys in parts of the Karaj plain revealed no pronounced subsidence indicators. The findings highlight a strong spatial correlation between the severity of subsidence and geological heterogeneity and unregulated groundwater exploitation.The absence of smart metering systems in wells also contributed to this issue. This study underscores the urgent need for integrated monitoring frameworks, adaptive management strategies, and the application of advanced remote sensing technologies to mitigate and control the expansion of land subsidence in Alborz Province.
Akramalsadad Ghadami, Houshang Khairy, Ebrahim Rahimi,
Volume 20, Issue 1 (6-2026)
Abstract
Land subsidence is one of the major geomorphological hazards in arid and semi-arid regions. It is primarily caused by excessive groundwater extraction. In such areas, a decline in groundwater levels can lead to the irreversible compaction of fine-grained layers, a reduction in storage capacity, and damage to critical infrastructure. This study aims to monitor the rate of land subsidence in the Damghan aquifer and analyse its relationship with groundwater decline, using satellite data, piezometric information and field evidence. The study area covers part of the Damghan aquifer in Semnan Province, spanning approximately 1,522 km². It contains an unconfined aquifer within heterogeneous alluvial deposits. The dataset includes Sentinel-1A images from 2017 to 2021, records from 38 observation wells from 2017 to 2022, and drilling logs from 13 exploitation boreholes. The results indicated that the decline in groundwater levels in the central and south-eastern parts of the aquifer reached 5 metres, with an average annual rate of approximately 0.33 metres. Radar interferometry maps confirmed an average Analysis of soil texture and saturated thickness revealed that zones with higher percentages of clay and silt are more sensitive to groundwater decline. Even small drawdowns in boreholes containing fine-grained sediments resulted in noticeable subsidence, whereas boreholes containing coarse-grained sediments showed limited deformation. Field evidence, including casing protrusion in piezometer wells of up to 27 cm, the formation of initial sinkholes and changes in natural drainage patterns, highlights the practical implications of this phenomenon. The findings of this study demonstrate that, in interaction with geological characteristics and soil texture, groundwater decline is the main driver of subsidence in the Damghan aquifer. Therefore, continuous groundwater monitoring and targeted management of exploitation are essential to mitigate risks and ensure the region's environmental and economic sustainability.
Salman Shamsoddini Motlagh, Saeed Mahdavi,
Volume 20, Issue 1 (6-2026)
Abstract
Due to the deepening of open-pit mines and associated environmental concerns, the current period has been termed the 'return to underground mining era'. One of the key factors in transitioning from open-pit to underground mining is designing crown pillars based on economic and technical considerations. Due to the uncertainties surrounding this research topic, the present study uses three-dimensional numerical simulations to investigate the interactive effects of geometric and geomechanical parameters on the behaviour of crown pillars during the transition to underground mining. Pillar behaviour was evaluated based on displacement magnitude and the volume of the plastic zone of the pillar. The results of the numerical simulation showed that geometric parameters play a much more significant role than rock mechanical properties. Of the geometric parameters, the pillar dimension index (the product of the pillar's thickness and span) and the crown pillar's span play a decisive role in controlling pillar behaviour. From a geomechanical perspective, within the range of variations considered in this research, the rock elastic modulus was identified as the parameter most influential on crown pillar behaviour. This parameter controls crown pillar behaviour at a critical value of 7 GPa. Crown pillar span was identified as the second most influential parameter and can predict crown pillar displacement with a correlation coefficient of 0.83. The pillar dimension index can estimate the plastic zone volume in the pillar with 20% accuracy.
Dr Seyed Ali Asghari Pari,
Volume 20, Issue 1 (6-2026)
Abstract
This study systematically compares probabilistic slope stability analyses performed using three widely used geotechnical engineering software packages: PLAXIS LE V21, GeoStudio 2024 (SLOPE/W module) and Slide2. Probabilistic analysis has emerged as an essential approach for quantifying uncertainties and calculating key metrics such as probability of failure and reliability index, given the critical importance of risk assessment and the inherent uncertainty in soil parameters. This research evaluates the capabilities, accuracy and efficiency of each software package, as well as their respective limitations, by performing identical analyses on three distinct scenarios (homogeneous soil, three-layered soil and pseudo-static conditions) while employing ten common limit equilibrium methods. The results show that, as the complexity of the problem increases, the factor of safety decreases while the probability of failure and discrepancies between the software packages increase. In the homogeneous scenario, the mean factor of safety ranges from 1.35 to 1.55, depending on the method selected, with a failure probability of 8–12%, and inter-software differences of less than 5%. In the layered scenario, the mean factor of safety decreases to 1.30–1.40, with inter-software discrepancies reaching approximately 15%. Under pseudo-static conditions, the mean factor of safety reduces by around 21% (to 1.15), the probability of failure rises to an average of 27%, and the inter-software discrepancies reach 25%. Advanced methods (Morgenstern-Price and Spencer) yield higher safety factors than simple methods (Ordinary/Fellenius). In terms of software performance, Plaxis LE offers the greatest accuracy in complex conditions, GeoStudio provides the most conservative estimates and, thanks to its advanced graphical tools, Slide2 is a suitable option for probabilistic risk assessment.
Dr. Manoochehr Mortazavi Chamchali, Dr. Ghazaleh Mohebbi Tafreshi, Dr. Amin Mohebbi Tafreshi,
Volume 20, Issue 1 (6-2026)
Abstract
Situated in northern Iran, Manjil City faces significant seismic risk due to its proximity to active fault systems and its role as a corridor for critical regional infrastructure. Past catastrophic events have emphasised the need for robust spatial risk assessment to mitigate the impact on people, the economy and infrastructure. This study presents a comprehensive seismic risk assessment and spatial zonation for Manjil, employing an integrated multi-criteria evaluation approach that couples Geographic Information Systems (GIS), the Analytic Hierarchy Process (AHP) and fuzzy logic. Risk was modelled as a function of the interaction between seismic hazard potential and spatial vulnerability. Vulnerability indicators, including residential density, land use patterns and critical urban infrastructure, were standardized and weighted using the AHP framework. Our findings suggest that high-density residential areas primarily contribute to urban vulnerability, whereas critical infrastructure components play a disproportionately vital role in emergency response scenarios.. In the hazard assessment, a range of proxies were analyzed, including proximity to faults, fault density, peak ground acceleration (PGA), active tectonic indices, topographic slope, and lithological characteristics. These parameters reveal heightened hazard levels in zones adjacent to active faults. By applying fuzzy membership functions and a gamma operator (γ=0.9), we generated an integrated earthquake risk map, classified into five vulnerability tiers ranging from ‘very low’ to ‘very high’ Spatial analysis revealed four distinct high-risk focal zones within the urban footprint, driven by the convergence of elevated seismic hazards and dense concentrations of residential and critical infrastructure. This research demonstrates the efficacy of the GIS–AHP–Fuzzy integration in providing a reliable, data-driven framework for evidence-based urban planning and proactive seismic risk management in seismically prone areas.
Hossein Mohammadzadeh, Nazanin Nesari Ashkzari, Mahmoud Arjmand Sharif,
Volume 20, Issue 1 (6-2026)
Abstract
The intensive exploitation of groundwater resources in arid and semi-arid regions poses serious challenges to the quantitative sustainability of aquifers. The Mashhad–Chenaran aquifer, one of the most important alluvial aquifers in north-eastern Iran and the main source of drinking water for the city of Mashhad, has experienced increasing stress in recent years. This study evaluated the quantitative sustainability of the aquifer during the 2015–2016 to 2021–2022 hydrological periods, based on an integrated analysis of well discharge, aquifer saturated thickness, specific yield (Sy), specific capacity (Q/s) and specific drawdown (S/Q). The results indicate a notable decline in well discharge, particularly in the southeastern and central parts of the aquifer. Concurrently, the saturated thickness of the aquifer decreased. Specific yield declined from approximately 0.95 to 0.25, corresponding to a reduction of around 74% in aquifer storage capacity. Additionally, the specific capacity decreased from approximately 0.63 to 0.43 MCM·yr⁻¹·m⁻¹, representing a reduction of around 32%. Meanwhile, specific drawdown increased from approximately 1.56 to 2.30 m, indicating a 47% increase in water-level decline per unit discharge, as well as a reduction in the hydraulic efficiency of groundwater exploitation. Areas of the aquifer were assessed for sustainability during the 2021–2022 hydrological period, and it was found that approximately 35% of the aquifer area was classified as unstable, 42% as semi-stable, and only 23% as stable. Overall, the findings demonstrate an intensification of quantitative instability in the Mashhad–Chenaran aquifer, emphasising the need to revise groundwater abstraction practices, control pumping rates and implement continuous monitoring to ensure the aquifer is exploited sustainably.
