1.INTRODUCTION Some forty years ago, most opening supports and reinforcements were designed using empirical rules defining ground loads acting on the supporting structures. This approach is still popular and interest in it has been renewed by the use of rock mass classification systems (Barton et al. 1974, Bieniawski, 1974,1976,1989). Correlations between rock mass conditions and the type of su...

correct estimation of water inflow into underground excavations can decrease safety risks and associated costs. researchers have proposed different methods to asses this value. it has been proved that water transmissivity of a rock joint is a function of factors, such as normal stress, joint roughness and its size and water pressure therefore, a laboratory setup was proposed to quantitatively m...

In underground tunnels or caverns, time-dependent deformation or failure of rock mass, such as extending cracks, gradual rock falls, etc., are a costly irritant and a major safety concern if the time-dependent damage of surrounding rock is serious. To understand the damage evolution of rock mass in underground engineering, an in situ experimental testing was carried out in a large belowground t...

The quasi-static theory of poroelasticity presented by Biot and Gassmann provides a relationship between the drained and undrained elastic constants of an isotropic fluid-saturated porous material in terms of the porosity of the material, bulk modulus of the solid grains, and bulk modulus of the pore fluid. We have developed an alternative approach to derive the Biot-Gassmann (BG) relationship ...

To obtain the effect of fracture failure mechanics characteristics and behavior brittle rock masses on compound factors fissure openings inclination, uniaxial loading tests were performed single-fissured rock-mass specimens with different using a test machine. The results show that increase in openings, fissured peak strength variation inclination angle changes from first decreasing then increa...

High-modulus asphalt mixes are effective means to solve rutting problems, but they perform poorly at low temperatures. This study aims enhance the modulus and low-temperature properties of mixes. Firstly, composite-modified asphalts were prepared by incorporating rubber powder rock asphalt. Secondly, their mechanical viscoelastic investigated determine appropriate mass ratios in be 20% 6%, resp...

The size effect has a significant on the mechanical behavior of rock, thereby fundamentally influencing stability rock excavations. main challenge associated with experimental research fractured mass lies in difficulty specimen preparation to represent influence and fracture material. In order preliminarily explore feasibility 3D printing technology field mechanics, specimens different sizes ch...

Original scientific paper Rock generally contains various micro-cracks, fissures, pores, joints, and other defects. These defects affect the mechanical properties of rock. In order to clarify the influence of native fissures on rock deformation and failure modes, a laboratory study was carried out using the fissured dolomite, and acoustic wave velocity measurement and natural water absorption t...

The evaluation of local stability of the tunnel surrounding rock mass with weak rock layer is very important for the economy and security of the tunnel construction. Based on the rock tunnel geological conditions in the construction, the finite element model of the tunnel surrounding rock mass stability analysis with weak rock layer is established in the article by selecting the ABAQUS program ...