- Email: [email protected]
Coredrilling over water — one contractor's experience
20A and geotechnical properties showed that the cutting specific energy and tool forces could be predicted from drill bit rates. The performance of the Russian Pk9r and Dosco MK-2A roadheaders were recorded. Machine utilization time. average daily progress rates and other parameters were compared. A good statistical relationship was found between machine advance rates and penetration rates of a selected percussive drill.
Blasting 861154 Coredrilling over water - one contractor's experience Braithwaite, R W Geodrilling N33, Aug 1985, P12-17 Two case studies of core drilling of marine rocks and soils, with special reference to coring very soft materials in small diameters, are presented. They are the seabed site investigation for jetties at the Sullom Voe oil terminal, Scotland, and site investigation in the North Sea's North Rankin gas field.
861157 Behaviour of bolts in rock and testing of rock bolts Brask, C G: Maki, K Swedish Detonic Research Foundation report DS 19~'4.6. 26" Dec" 1984.46P The behaviour of bolts in rocks is reviewed. Interaction of" grouted bolts with hard and soft rocks is examined by reference to case studies. In hard rocks, the bolt deformation is concentrated in the vicinity of the cracks and both shear and axial deformations occur. In soft rocks, axial deformation is more evenly distributed along the bolt. The problems of testing of bolts are discussed, and it is suggested that becavse of the numerous site-specific variables, tests performed under different conditions cannot be compared. Laboratory testing, simulating a dilating joint, and in situ pull testing are described. For soft rocks axial testing is more important, but for hard rocks, both shear and axial testing are required.
Avail: The Foundation, Box 32058, S-126 11 Stockholm, Sweden
Shotcrete
Rock and Soil Reinforcement and Support 861155 Tank farm construction over soft organic clays - a case history Ahmed, S Proc International Conference on Case Histories in
Geoteclm&al Engineering, Rolla, Missouri, 6-11 May 1984 V1, P271-274. Publ St Louis. Geotechnical Engineering, 1984 The soil improvement program for a tank farm is described. After site investigation, drains were installed where necessary. Consolidation was monitored by pore pressure measurement, and settlement, heave and lateral soil deformation measured. A new design of tank ringwall is described, and a simple direct parameter, R, (the ratio of increase in pore pressure to applied surface load) to monitor soil response, is introduced. This parameter is easier to measure than effective stress.
Bolts and anchors See also: 861254
861156 Ultimate pullout capacity of shallow vertical anchors in clay. Technical note Das, B M, Moreno, R; Dallo, K F Soils Found V25, N2, June 1985, P148-152 Small scale model tests on shallow vertical anchors in saturated clay are described. From analysis of test results, a nondimensional breakout factor is derived, which can be used to express the ultimate pullout resistance. For shallow anchors, this factor increases with embedment ratio (depth of embedment/anchor height), and at constant embedment ratio it increases with decreasing width/height ratio of the anchor. Full scale testing is needed to verify these results and investigate scale effects.
861158 Shotcrete in roads and shafts of Bergban AG Lippe Thierse, D Giuekauf V121, N14, 25 July 1985, PI076-1090 (german), P326-331 (english) The use of shotcrete, bolt-shotcrete, spray-on grout and colloidal cement,placed by slinging, are described. These techniques are used for shaft and borehole linings, permanent and temporary support in driveways and for lining large underground caverns. Support schedule, application, the composition and processing of shotcrete, use in conjunction with steel arches, and cost effectiveness are discussed.
861159 Steel fibre shotcrete lends support to the NATM Grondziel, M Tunn Tunnig VI7. N9, Sept 1985, P48-50 Fibre reinforcement improves the mechanical properties of shotcrete. Until recently the usc of steel fibre shotcrete has been machine intensive and complicated, but triangular fibres, with one smooth and two rough surfaces, milled from steel slabs, have removed this drawback. Their use to support tun-. nels near Koblenz, Germany, is described.
Direct rock support methods 861160 Compaction behaviour of stowing material containing binders (In German) Helms, W; Knissel. W Gluckauf-forsehungsh V46, N4, Aug 1985, P186-191 The effectiveness of packing materials containing binders is largely determined by their compaction behaviour, which differs from that of binder free material. These materials are load bearing at an early stage and show little settlement. Uniaxial compressive strength is the most important compaction parameter.
Blasting 861154 Coredrilling over water - one contractor's experience Braithwaite, R W Geodrilling N33, Aug 1985, P12-17 Two case studies of core drilling of marine rocks and soils, with special reference to coring very soft materials in small diameters, are presented. They are the seabed site investigation for jetties at the Sullom Voe oil terminal, Scotland, and site investigation in the North Sea's North Rankin gas field.
861157 Behaviour of bolts in rock and testing of rock bolts Brask, C G: Maki, K Swedish Detonic Research Foundation report DS 19~'4.6. 26" Dec" 1984.46P The behaviour of bolts in rocks is reviewed. Interaction of" grouted bolts with hard and soft rocks is examined by reference to case studies. In hard rocks, the bolt deformation is concentrated in the vicinity of the cracks and both shear and axial deformations occur. In soft rocks, axial deformation is more evenly distributed along the bolt. The problems of testing of bolts are discussed, and it is suggested that becavse of the numerous site-specific variables, tests performed under different conditions cannot be compared. Laboratory testing, simulating a dilating joint, and in situ pull testing are described. For soft rocks axial testing is more important, but for hard rocks, both shear and axial testing are required.
Avail: The Foundation, Box 32058, S-126 11 Stockholm, Sweden
Shotcrete
Rock and Soil Reinforcement and Support 861155 Tank farm construction over soft organic clays - a case history Ahmed, S Proc International Conference on Case Histories in
Geoteclm&al Engineering, Rolla, Missouri, 6-11 May 1984 V1, P271-274. Publ St Louis. Geotechnical Engineering, 1984 The soil improvement program for a tank farm is described. After site investigation, drains were installed where necessary. Consolidation was monitored by pore pressure measurement, and settlement, heave and lateral soil deformation measured. A new design of tank ringwall is described, and a simple direct parameter, R, (the ratio of increase in pore pressure to applied surface load) to monitor soil response, is introduced. This parameter is easier to measure than effective stress.
Bolts and anchors See also: 861254
861156 Ultimate pullout capacity of shallow vertical anchors in clay. Technical note Das, B M, Moreno, R; Dallo, K F Soils Found V25, N2, June 1985, P148-152 Small scale model tests on shallow vertical anchors in saturated clay are described. From analysis of test results, a nondimensional breakout factor is derived, which can be used to express the ultimate pullout resistance. For shallow anchors, this factor increases with embedment ratio (depth of embedment/anchor height), and at constant embedment ratio it increases with decreasing width/height ratio of the anchor. Full scale testing is needed to verify these results and investigate scale effects.
861158 Shotcrete in roads and shafts of Bergban AG Lippe Thierse, D Giuekauf V121, N14, 25 July 1985, PI076-1090 (german), P326-331 (english) The use of shotcrete, bolt-shotcrete, spray-on grout and colloidal cement,placed by slinging, are described. These techniques are used for shaft and borehole linings, permanent and temporary support in driveways and for lining large underground caverns. Support schedule, application, the composition and processing of shotcrete, use in conjunction with steel arches, and cost effectiveness are discussed.
861159 Steel fibre shotcrete lends support to the NATM Grondziel, M Tunn Tunnig VI7. N9, Sept 1985, P48-50 Fibre reinforcement improves the mechanical properties of shotcrete. Until recently the usc of steel fibre shotcrete has been machine intensive and complicated, but triangular fibres, with one smooth and two rough surfaces, milled from steel slabs, have removed this drawback. Their use to support tun-. nels near Koblenz, Germany, is described.
Direct rock support methods 861160 Compaction behaviour of stowing material containing binders (In German) Helms, W; Knissel. W Gluckauf-forsehungsh V46, N4, Aug 1985, P186-191 The effectiveness of packing materials containing binders is largely determined by their compaction behaviour, which differs from that of binder free material. These materials are load bearing at an early stage and show little settlement. Uniaxial compressive strength is the most important compaction parameter.