the rock masses in a construction site of underground cavern are generally not continuous, due to the presence of discontinuities, such as bedding, joints, faults, and fractures. the performance of an underground cavern is principally ruled by the mechanical behaviors of the discontinuities in the vicinity of the cavern. during underground excavation, many surrounding rock failures have close r...

geophysical techniques remain the only ways to remotely and non-destructively sense the earth’s near subsurface and as such have the most promising prospect for rapid and accurate detection of underground tunnels. today, electrical resistivity and seismic refraction geophysical methods have been greatly developed to identify structures and underground cavities. in this study, the ability of the...

the construction of underground tunnel plays a more and more important role in the development of big cities. one of the most important problems caused by the construction of the tunnel is that underground excavation will cause large settlement of the ground and buildings. previous studied showed the difference between numerical and experimental results. in this study the case study of niyayesh...

With the large-scale construction and rapid development of underground engineering, a large number of underground engineering construction, such as tunnel and subway emerged. The geological structure of the tunnel is complex and the roc is fragmented. Tunnel seismic image is a new geophysical technique. This method has advantages such as high resolution, high reliability and obvious image chara...

The rock masses in a construction site of underground cavern are generally not continuous, due to the presence of discontinuities, such as bedding, joints, faults, and fractures. The performance of an underground cavern is principally ruled by the mechanical behaviors of the discontinuities in the vicinity of the cavern. During underground excavation, many surrounding rock failures have close r...

For enhancing low lumination image of underground mine tunnel, a hybrid local histogram equalization with partial differential equation is proposed to combine a local histogram equalization and total variation method with edge-stopping function via partial differential equation. The local histogram equalization is to enhance contrast of image with keeping shape and edge, while total variation m...

The use of hydrothermal simulation models to improve the prediction of water inflows in underground works during drilling is tested in the Mont-Blanc tunnel, French and Italian Alps. The negative thermal anomaly that was observed during the drilling of this tunnel in 1960 is reproduced by long-term, transient hydrothermal simulations. Sensitivity analysis shows the great inertia of thermal phen...

Excess pore pressure under seismic loadings has always been a main concern in geotechnical engineering practices. Undergoing the phenomenon in a soil can cause the effective stress and hence the shear strength of the soil to decrease considerably and large deformations happen in the area. Generally, increasing the pore pressure occurs under the undrained condition. If it can be formed the drain...

Purpose Tunnel construction using a tunnel boring machine (TBM) entails precise machine positioning and guidance in the underground space. In contrast to traditional laser-based machine guidance solutions, the proposed research aims to develop an automation alternative to facilitate TBMguidance and as-built tunnel alignment survey during tunnelling operations. Method A fully automated system is...

In underground mines and tunnels accurate and continuous positioning of moving machines and humans has been studied extensively. Geomagnetic field based positioning is an interesting possibility for this measurement need. Using a commercial smart phone and a new calculation service provided by a Finnish company, a feasibility and accuracy assertion tests were done in Finnish underground mine. F...