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The influence of jointing on the stability of adjacent rock mass is analyzed using the coefficient of structural weakening and the joint spacing. The gravity–tectonic stress field of ore bodies in Gornaya Shoria, including the azimuth of the principal horizontal stresses is characterized. The laboratory tension tests of combinations of support systems as well as the small-scale extension tests of rock bolts made of different materials are discussed. The framework for a multi-factor digital model of safe and efficient support design for iron ore mines in Gornaya Shoria is based on the stability assessment of adjacent rock mass in terms of jointing and stress state.

Safety during construction and long-term stability of tunnels is among important factors in the design and implementation of underground spaces. Since tunnels and underground spaces are under dynamic loads such as earthquakes and explosions during construction and operation stages, dynamic stability analysis of such structures is of great importance. In this study, the twin tunnels of Shiraz subway were numerically modeled under static and dynamic loads with the help of Universal Distinct Element Code (UDEC). This is a finite element method (FEM) software, is any of a family of numerical methods. Unbalanced forces increase after tunnel excavation and applying static and dynamic loads. Although the increase in unbalanced forces was higher under dynamic loads, under static loads, velocity and displacement changes in the ceiling of the tunnel were higher than the rest of the tunnel. To apply a dynamic load, a sine wave was applied to the lower boundary of the model. After applying the dynamic load, velocity and displacement changes of the tunnel floor were higher than the rest of the tunnel. According to modeling results, the twin tunnels are quite unstable under static and dynamic loads and need a support system.

The support systems of excavations (such as underground mining openings and water tunnels) experience the time dependent induced pressure of the ground in vicinity of swellable rock. This research examines the interaction of swellable rock under different initial pressure to simulate the behavior of such rocks behind the support systems. A device was designed and constructed to model the condition in laboratory. Marlstone samples from Marash project in North West of Iran were chosen to perform the tests. The swelling pressure under different initial support pressure (ISP) was measured over time. The lowest swelling pressure was recorded under the minimum initial pressure. The swelling pressure of samples do not expose under high ISP (about 5 times of the steady swelling pressure). The differential swelling pressure (swelling pressure minus the ISP) generally increases from a minimum, at the lowest initial pressure, to a maximum, at the initial pressure equal to the steady swelling pressure. After reaching this maximum value, the differential pressure reduces back to zero where the ISP hampers the swelling phenomenon.

an increasing use is being made of models for studying powered support system. The main aim of this research work is to design the power support system that is designed for the longwall face which operating in different geological conditions with the use of successfully empirical and modeling technics which takes into account the health of the hydraulics supports, the efficiency of the hydraulic supply system and the cleanliness/load bearing capacity of roof is also suggested, enabling management to ensure that the support system is used at maximum efficiency.