Search published articles


Showing 84 results for kh
Numerical analysis and investigation of axial force, shear force and horizontal displacement in underground structures (case study: pataveh-Dehdasht tunnel)
Masoud Khahanipour, Hossein Sarbaz,
Volume 19, Issue 4 (12-2025)
Abstract
This study aims to numerically analyze the axial force, shear force, and horizontal displacement in Tunnel B on the Pataveh-Dehdasht axis. The tunnel is part of a national project that was inaugurated in the summer of 2023. The project's technical specifications include 2.2 million cubic meters of earthwork, 2,100 meters of retaining walls, 110,000 tons of subbase and base layers, and 95,000 tons of asphalt. This study investigated the effect of tunnel lining thickness on shear force, axial force, and horizontal and vertical displacement using PLAXIS finite element software in a two-dimensional framework. Plane strain theory was employed with 15-node elements for modeling. The Mohr-Coulomb constitutive model, one of the fundamental stages in numerical analysis and a common model for tunnel excavation simulations, was applied to model the soil behavior of the study site. The results indicate that increasing the lining thickness reduces vertical and horizontal displacement at all points while increasing axial and shear forces. Maximum deformation occurs at the tunnel invert and minimum deformation occurs at the right sidewall of the tunnel. Increasing the lining thickness from 20 cm to 35 cm leads to a reduction of approximately 100% in tunnel floor settlement and a significant decrease in horizontal displacement exceeding 90% at certain points. These results demonstrate the importance of selecting an appropriate lining thickness for controlling deformations, enhancing load-bearing capacity, and improving the tunnel's seismic safety.

Integration of empirical and systems engineering frameworks in tunnel support design: a comprehensive study of 38 tunnels in Iran
Dr Seyed Mahmoud Fatemi Aghda, Dr Mehdi Talkhablou, Habibolah Heidari,
Volume 19, Issue 5 (English articles 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.

A field-based investigation of land subsidence indicators in Alborz province
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.

Determining land subsidence rate and its relationship with groundwater level decline using satellite data in the Damghan aquifer
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.

Page 5 from 5     

© 2026 CC BY-NC 4.0 | Journal of Engineering Geology

Designed & Developed by : Yektaweb