Analysis of tunnel behaviour in discontinuous rock masses

Analysis of tunnel behaviour in discontinuous rock masses

196A 884341 3-d model tests for shallow rock-bolted tunnels (In German) Egger, P 884345 Interpretation of tunnel convergence measurements Barlo~.. J ...

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196A 884341 3-d model tests for shallow rock-bolted tunnels (In German) Egger, P

884345 Interpretation of tunnel convergence measurements Barlo~.. J P

Proc 6th International Conference on Rock ,Wechanics, Montreal, 30 Aug-10 Sept 1987 V2. P865..~70 Puhl Rotterdam. A A Balkema. 1987

Proc 6th International Conference on Rock Alechanics, Alontreal, 30 Aug-iO Sept 1987 V2. P787.792 Publ Rotterdam A A Balkema. 1987

A series of 3-d geomechanical tests is used to simulate the cutting of shallow' tunnels in poor ground. Passive and prestressed bolts are used for support and results show prestressed bolts to be superior. Surface settlements and tunnel stability are compared with analytical and numerical predictions, as well as the results of monitoring 2 tunnels.

A modification of the convergence equation of Guenot et al to make it more realistically applicable is presented. Three equations are developed to describe convergence ahead and behind the face of a supported tunnel. The equations are applied to the Enasan Tunnel, Japan. and give valuable information about response of the rock mass to excavation and support, time dependent behaviour and the yield zone. The method enables prediction of long term response of a rock mass and the effect of a variety of support systems.

884342 Highway tunnels in Liege: geomechanical characteristics of the rock and evaluation of support pressures by different methods (In French) Delapierre, J; Pohl. E; Funckcn, R; Latour. F: Nomerange. J: Marchal, J P

Proc 6th International Conference on Rock Mechanics, Montreal, 30 Aug-10 Sept 1987 V2. P855-858. Publ Rotterdam: A A Balkema. 1987 Geometry. geomechanics and theology of a rock mass during excavation of 2 road tunnels in Liege is investigated using data from 3 wells and 100 boreholes, and 5 methods (AmbergLombardi. Egger-Descoeudres, Goodman. Hock and Brown (schist) and Hock and Brown (sandstone)) to calculate loading pressure on the tunnel lining are discussed. Bieniawski's method is used for rock mass classification. Results of the 5 methods are compared and show good correlation

884343 Analysis of tunnel behaviour in discontinuous rock masses Cunha. A P

Proc 6th International Conference on Rock Mechanics, ,Wontreal, 30 Aug-10 Sept 1987 V2. P845-848. Publ Rotterdam. A A Balkema. 1987 A simplified analysis of tunnel wall detbrmation for a deep tunnel in a jointed rock mass is presented. Joint properties (mechanical strength, cohesion and friction angle), rock elastic properties and horizontal/vertical stress ratio are varied. Two cases are examined - a simple horizontal joint set and two joint sets. one horizontal, one vertical. Displacements along the joints and the tunnel, stresses along the joints and safety factors against sliding are calculated.

884346

Case study of two tunnels driven in the Singapore 'boulder bed', and in grouted coral sands Shirlav,, J N: Doran. J: Benjamin, B

Proc 23rd Annual Conference of the Engineering Group of the Geological Society, Engineering Geology of Underground Movements, Nottingham, 13-17 Sept 1987 P35-62 Publ Nottingham: Unicersity of Nottingham. 1987 Ground movements were monitored during excavation of tunnels using the New Austrian Tunnelling Method. The results indicate that settlement over these tunnels was lower than over shield driven tunnels nearby. This is attributed to the quick and direct support provided by the shotcrete lining used.

884347 Tunnelling through frozen ground - a case history at Iver, Bucks Griffin, A R

Proc 23rd Annual Conference of the Engineering Group of the Geological Society, Engineering Geology of Underground ~t4ovements, Nottingham, 13,17 Sept 1987 P63-76. PuM Noningham: University of Nottingham. 1987 Excavation of a tunnel in lver, Bucks, was affected by anomalous ground conditions, consisting of a deep. gravel filled scour hollow. A combination of claquagc and gel grouting. followed by ground freezing with liquid nitrogen was successful in stabilising the ground

884344 Effects of the extraction of tabular deposits around vertical shafts in deep-level mines Budavari. S: Croeser. R W

884348 Multiple correlation at the foundation of a test embankment under different overburden pressure conditions Dubois, R

Proc 6th International Conference on Rock Mechanics, Montreal, 30 Aug-10 Sept 1987 V2. P825-828. Publ Rotterdam: A A Balkema. 1987

Proc 5th International Congress International Association of Engineering Geology, Buenos Aires, 20-25 October I986 I/2. PI411-1415. Publ Rotterdam: A A Balkema. 1986

The use of pillars for support below 2.5-3km is uneconomic. An alternative is to extract the orebody early in the life of the shaft and limit the ensuing damage by controlling the strata displacement. The effects of such extraction on the hangingwall strata are examined and modelled for a linearly isotropic elastic rock mass. Comparison of computed and measured values indicates that if an estimate of the in situ modulus can be obtained, use of the elastic model gives acceptable prediction of vertical induced strain.

A 17m high test hydraulic fill embankment was constructed as part of the Parana Medio Project, Brazil. Dam foundations were of soft cohesive soils and silty sand strata. Tests were made across a profile to examine the effects of overburden pressure on geotechnical properties. Undrained cohesion from triaxial tests, shear vane strength, and SPT N value were plotted against effective overburden pressure. The improvement in foundation soil conditions and the validity of the test methods at different depths were examined.

C 1988 Pergamon Press pie. Reproduction not permitted