elastic solutions applicable to single underground openings usually suffer from geometry related simplification. most tunnel shapes possess two axes of symmetry while a wide range of geometries used in tunneling practice involve only one symmetry axis. d-shape or horse-shoe shape tunnels and others with arched roof and floor are examples of the later category (one symmetry axis). in the present...

Dimensionless coefficient () in convergence confinement method shows the relaxation of stress in the wall of the tunnel at different excavation movements. This factor is considered a constant number in previous studies and tunnel geometric characteristics (such as depth, cross-section shape, radius, soil material, etc.) are not included in its determination; however, ignoring these effects can...

among various practical measures used for restriction of the ground surface settlement in such tunnels driven in soft ground, selection of an appropriate excavation method plays a significant role. in this paper, employing suggested diagram by yu & chern, corresponding values of niayesh tunnel has been inserted into the diagram. later, two excavation methods namely: central diaphragm and si...

AIM The aim of this study was to try to find parametric ratios for the diagnosis and pathophysiology of carpal tunnel syndrome using MR. MATERIAL AND METHODS Dominant side wrist MRI examinations of 27 female carpal tunnel patients and 21 normal females were compared. The carpal tunnel contents area / carpal tunnel cross section area ratio was defined, analysed and discussed with the literatur...

An efficient method for the continuous extraction of subway tunnel cross sections using terrestrial point clouds is proposed. First, the continuous central axis of the tunnel is extracted using a 2D projection of the point cloud and curve fitting using the RANSAC (RANdom SAmple Consensus) algorithm, and the axis is optimized using a global extraction strategy based on segment-wise fitting. The ...

BACKGROUND Although controversial, recent studies have demonstrated advantages of sonographic techniques in the diagnosis of carpal tunnel syndrome (CTS). The purpose of this study was to assess the utility of median nerve ultrasonography in the diagnosis of CTS in Iranian patients. METHODS Ninety patents with clinically suspected CTS were studied. Based on gold standard electromyography/nerv...

This report describes the conversion of an existing large-cross-sectionalarea tunnel into a shock tube and the evaluation of the capabilities of this facility for blast loading and response studies of full-scale and large-scale structural elements. Also included are the results from a preliminary test series of full-scale wall panels conducted as part of the evaluation program and the design of...

nowadays deep excavations are needed for construction of foundation of high rise buildings, providing space for parking and etc. in some cases deep excavations may be constructed in the vicinity of the subway tunnels and causes unpredicted extra displacements and internal forces in tunnel lining of tunnels which were not designed for them and consequently affect serviceability of tunnel. theref...