256A UNDERGROUND EXCAVATIONS :TUNNELS

945261 Contribuicao ao estudo dos movimentos tec- tonicos sin e pos-sedimentares na Bacia de Sao Paulo a partir de evidencias observadas nas escavacoes do tunei da eletropaulo (Contribution to the study of tectonic movements during and after the sedimentation of Sao Paulo Basin based on geological observations during the underground excavation of the eletropaulo tunnel) V.M. Cozzolino, L. Rogerio Martinati & A. V. DeAnna Buono, Solos e Rochas, 17(1), 1994, pp 13-29. This article describes: 1) the geological classifications of the underground crossed by the tunnel; 2) the conglomeratic lithic sediments found on a bedrock outcrop and near a fault; 3) the hydro-geotechnical characteristics of the soil crossed by the tunnel; 4) the occurrence and nature of thick layers of hard greenish-gray silty clay in Pari district; 5) the existence of silty clay beds that are abruptly interrupted and partly lowered, between the Alcantara Machado Avenue and the Tamanduatei River; 6) the origin of low overconsolidation ratio of motley silty clay in the center of the city, in relation to the sedimenta- tion filling level of San Paulo Basin, based on the geologi- cal evidence presented here. -from English summary

945262 Geotechnical aspects of the Lesotho Highlands Water Project D. C. R. MacKellar, in: Geotechnics in the African environment. 1Iol. 2, ed G.E. Blight & others, (Balkema), 1994, pp 467-473. This chapter provides an overview of the most important geotechmcal aspects of the .project. A brief summary of the geology encountered is given before the geotechnical design of roads, dam site selection, and the materials used are discussed. The geotechnical studies for tunnels are detailed, including expected tunnel boring machines, and rock types encountered. A description of the site investiga- tions, and the techniques used are given. -R.Gower

945263 Die baugeoiogischen Verhaltnisse des Inntal. tunnels (The geological/constructional situation of the Inntaltunnel) W. l.,oimser & M. Kohler, Felsbau, 12(2), 1994, pp 69-76. Two percent of the Inntaltunnel penetrates unconsolidated fluvioglacial rock, the remaining 98% was driven in solid rocks of the so-called 'Unterostalpiner Innsbrucker Quartzphyllit', i.e. quartz-chlorite-sericite-limestone. The

hyllites are interstratified with carbonate minerals in the orthem section and basic green schist facies in the South-

em section. A water-saturated sand layer at the Northern portal could only be mastered by taking special measures (pre-drainage). Shear zones of considerable thickness and

~ artial mylonitisation of larger rock zones resulted in the uih-up of heavy pressure with plastic deformation.

-from English summary

945264 Large-scale intrusion of shallow water into a vertical fracture zone in crystalline bedrock: initial hydrochemical perturbation during tunnel construction at the Aspo Hard Rock Laboratory, southeastern Sweden S. Banwart, E. Gustafsson, M. Laaksohar~u, A.-C. Nilsson, E.-L. Tullborg & B. Wallin, Water tcesources Research, 30(6), 1994, pp 1747-1763. Chloride ion is a natural conservative tracer for mixing between the dilute ([C1-] < 10 mg L "~) shallow groundwater and the saline ([C1-] = 5000 mg L -i) native groundwater of the fracture zone. A sharp dilution front, corresponding to 80% dilution of the native groundwater, indicated arrival of shallow groundwater in the entrance tunnel after 3 weeks. In spite of this large input of shallow water, the fracture zone remains predominantly anoxic. Major element hydro- chemistry and carbon and oxygen stable isotope data indi- cate l.arge inputs of alkalinity and biogenic CO2~.K ). Input of orgamc carbon with shaUow groundwater provi'd~s a possi- ble energy and carbon source for anaerobic respiration. There is no evidence for sulfate reduction, a n d Fe(III) oxyhydroxide fracture minerals are the only other dom- inant electron acceptor observed. -from Authors

945265 Seismic response of a cylindrical shell embed. ded in a layered viscoelastic half-space. I: formulation J.E. Luco & F. C. P. De Barros, Earthquake Engineering & Structural Dynamics, 23(5), 1994, pp 553-567. A method to obtain the three-dimensional harmonic response of a infinitely long cyclindrical shell of circular cross-section embedded in a layered viscoelastic half- space and subjected to harmonic plane waves impinging at an oblique angle with respect to the axis of the shell is presented. The procedure combines an indirect integral representation for the field in the exterior half-space with a model of the pipeline or tunnel based on Donnell shell theory. The integral representation for the soil is based on the use of moving Green's functions for the layered viscoelastic half-space. The accuracy of the formulation is tested by comparison of results obtained by using different discretizations. - from Authors

945266 Seismic response of a cylindrical shell embed- ded in a layered viscoelstic half-space. II: validation and numerical results F. C. P. De Barros & J. E. Luco, Earthquake Engineering & Structural Dynamics, 23(5), 1994, pp 569-580. A procedure to calculate the three-dimensional harmonic response of a infinitely long cyclindrical shell of circular cross-section embedded in a layered viscoelastic half- space and subjected to harmonic plane waves impinging at an oblique angle with respect to the axis of the shell is validated by extensive comparisons with previous two- and three-dimensional results for the particular case of a shell embedded in a uniform half-space. New numerical results described the motion and stress within a shell embedded in a multilayered half-space and subjected to obliquely incident P-, SV- and SH-waves with different horizontal angles of incidence are presented and discussed.

-Authors

Tunnels 945267 Tunnell ing '94 ANON, International Water Power & Dam Construction,

46(6), 1994, pp 50-51. Underground works for such hydropower projects as the Lesotho Highlands, Pergan and Serra da Mesa will be dis- cussed at the Tunnelling '94. This article previews the main hydropower papers to be presented at the conference next month. -from Author

945268 Tunnelbau braucht Innovationen fur die Aut- gaben tier Zukunft: vom Gestern zum Morgen (Tunnel- ling requires innovation to meet tomorrow's needs) B. Maidl, Felsbau, 12(3), 1994, pp 148-157. The development and the innovation for conventional tun- nelling and mechanical tunnelling, especially of the shield tunnelling technique is presented up to the latest state of the art. Interest is shown for construction techniques by the use of s.hotcrete including the NATM. Finally the deficit in mnovatmn and the future demands in tunnelling are presented. -English summary

945269 Norway's Rennfast link: the world's longest and deepest subsea road tunnel G. Espedal & G. Naerum, Tunnelling & Underground Space Technology, 9(2), 1994, pp 159-164. The western coast of Norway consists of many long fjords. This article describes how two of these fjords are crossed by two subsea road tunnels, 5860 m and 4405 m long, respectively. The longer tunnel, the Byfjord Tunnel, is the wofld°s longest and deepest subsea road tunnel, at 223 m below sea level. The paper describes the preliminary inves- tigations and geological conditions for the tunnels, each of which has three lanes, and a total width of 11 m.

-Authors

945270 Reminiszenzen zur Eroffnung des Kanai tun. nels (Opening of Euro-tunnel) M. John, Felsbau, 12(3), 1994, pp 146-147. At a ceremony on 6th of May 1994 her Majesty the Queen and the President of France, Mitterand, officially opened the Euro-Tunnel and joined Britain to Continental Europe