771154 ROCK ENGINEerING TESTING IN EXPLORATORY B~EHOLES Van Schalkwyk, A M Paper to Symposium on Exploration for Rock E~gineering, J o ~ a b u r g , Nov 1976. Proceedings, Vl, P37-5~
771159 BOHEHOLE STRUCTURAL LOGGING EMPLOYING A PNE~ICALLY II~ABLE IMPRESSION PACKER Barr, M V; Hocking, G Paper to Symposium on Exploration for Rock E~glneering, Johannaeburg, Nov 1976. Proceedings, Vl, P29-34
~,~]1 diameter exploratory boreholes ere drilled primarily for the retrieval of core samples. The usefulness of these bcreholes can be increased considerably by truing a variety of dcwn-hole mechanical, geophysical and hy~Irological tests to study the in-situ engineering properties of the surrouniing rock mass; A wide range of such tests is revi~ ed, with special attention being given to those techniques currently in use in South Africa including details of the equipment used anl examples to illustrate their merits and limitations.
Using a simple bore_hole impression packer utilising a deformable thermoplastic film, impressions of the walls of diamonl cored bcreholes in a slate anl a limestor~-chert formation have been obtained. Orientation and apertures of discontinuities in the limestonechert formation were determined from the borehole impressions. Good correlation exists between the structural data obtained from bore_holes stud from surface outcrops.
Core recovery, logging, probing, boring and sampling TTl155 IMPROVED
HYDRAULIC SAMPLER FOR OBTAINING UNDISTURBED SEDIMENT CORES Johnson, D L; Alexander, C S J Sedlm Petrol, V~6, NI, March 1976, P249-251
Reports modifications to a portable hydraulic coring device, which enable recovery of unliaturbed sediment cores 1.2 m in length. 771156 EXPERIENCES WITH UNDERGROUND SAMPLING OF ~MFLACED HYDRAULIC FILL Thomas, E G Proc Australas Inst Min Metall, N259, Sept
1976, ~5-51 The methods and equipment developed and used at the Mount I ~ mine to obtain samples of uncemented hydraulic fill lying above major horizontal pillars are described. From existing u~iergrour~ development, samples were obtained at distances up to 50 m, of which up to 30 m was through hard rock. Samples were used %o predict fill behaviour as it affected mining security during recovery af the pillars. Speclalieed equipment for difficult sampling situations anl also other sampling exercises are described. Auth.
771157 E X P L ~ R Y
DRILLING FOR ROCK ENGINE~RING Weaver, J M Paper to Symposium on Exploration for Rock Engineering, Johanresburg, NOV 1976. Proceedings, Vl, 917-24
Exploratory drilling practice in SouThern Africa in terms of develolmmnt of a drilling progrs~mue, spacing, depth and orientation of borings, penetration rates, drilling equil~nents core bmrrels, diamond bits, and selection of contractors is described. 771158 LARGE DIAMETER DRILLING IN ROCK Hartley, W F; Ball, R J Paper to Symposium on Exploration for Rock Engineering, Johannesburg, Nov 1976. Proceedings, VI, P25-28 Large diameter shafts to 1.5 m diameter can be drilled from ground level to depths of 300 m or more. Generally, they are drilled to service underground workings, but the technique may be extended to provide useful geotechnlcal information obtained from inspection or in-situ te sting.
INTEGRAL SAMPLING TECHNIQUE OF JOINTED ROCK MASSES Orr, C M; Traxler, K; Benzinger, E Paper to Symposium on Exploration for Rock Engineering, Johannesburg, Nov 1976. Proceedings, VI, P57-62 The integral sampling technique yields a piece of intact core from which it is possible to obtain detailed measurements of the orientation a ~ frequency of fractures intersected by the borehole as well as the thickness ard consistency of fault and Joint gouge material. The paper describes the technique a ~ equipment developed at the CSIR, South Africa, and the results obtained from an experimental test programme using the equipment.
771161 DETERMINATION OF R~D FRCM FETROSCOPE OB~RV~IONS Olivier, H J Paper to Symposium on Exploration for Rock Engineering, Johannesburg, Nov 1976. Proceedings, Vl, P63-68 A comparison of RQD values obtained at different depths from groups of boreholes drilled urder identical conlitions at various test localities in the Orates-Fish tunnel showed that the conventional core-loggir~ method gave unsatisfactory results, and that over-pessimistic ratings of rock mass quality were obtained. A new method is !:roposed for the indirect determination of RQD from petroscope observations in short exploratory bereholes drilled into the crown section of the tunnel.
LOG FOR ENGINEERING PURPOSES Page, T C; Orr, C M; Magni, E R Paper to Symposium on Exploration for Rock E~gincerimg, J~hannesburgl Nov 1976. Proceedings, Vl, P87-91
In the engineering borehole log described, both rock er~ncering a~i purely geological information is used to ~rovlde a comprehensive log of rock conditions. The tabular format reiuces the lik~!~hood of certain parameters being overloaded in the field, ard ensures that the variations in ir~lividual parameters may be readily observed.
Geophysical techniques 771163 REPORT OF ACTIVITIES, PART B. NOVEMBER 1973 TO MARCH 1974 Canada: Geological Survey paper 7~-IB, 1974, 297P Includes details of the following : a shipborne