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<br />llESIGN METHODS 1N ROCK ~IECHANICS~
<br />Figure 4. One of the highest rock cuts
<br />horizontal bedding plz nes in the direction out from
<br />the face and frequently reached several inches.
<br />Although no stability or roc kfall problems were
<br />caused by these displaced blocks, the displacement
<br />resulted in vertical open fractures, parallel and
<br />behind the cut face. These fractures comprise zones
<br />of increased permeability and may lead to rapid
<br />weathering and cut deterioration. Careful blasting
<br />was required to avoid this disturbance.
<br />CONCLUSIONS
<br />Although the road construction has recently
<br />been interrupted and postponed indefinitely, and the
<br />highest cuts have not been completed, the experience
<br />from the construction has been favorable. Vertical
<br />cut faces and horizontal benches appear to be a
<br />logical solution in these geologic conditions, from
<br />the points of view of stability, protection against
<br />rockfall, and blasting procedures.
<br />Finite element methods can provide useful data
<br />to su~~ort the design concept; to evaluate zones of
<br />tensile stresses; and eventually, to calculate the
<br />necesszry bolting forces.
<br />AL KNO'~_EDGMEtITS
<br />The finite element analyses were performed by
<br />Mr. Giiles Bureau, previous employee of Dames b
<br />Moore.
<br />REFERE'iCES
<br />AGAPIi0, JOSE F. T., 1974: "Rock Mechanics Applica-
<br />tions to the Design of Oil Shale Pillars", S~ovie~t of~
<br />Mining Engineers of A[ME, Preprint No. 74-AIM~6.
<br />BRADLEY, W. H., 1931: "Origin and Microfossils of
<br />the Oil Shale of the Green River Formation of
<br />Colorado and Utah", Professional Paper 168, U.S.
<br />Geolocical Survey.
<br />GOODM;tiI, R. E., TAYLOR, R. L., BREKKE, T. L., 1968:
<br />"A Model for the Mechanics of Jointed Rock", Journal
<br />of the Soil Mechanics and Foundation Division, ASCE,
<br />Vol. 9;, No. SM3.
<br />GOODMA!;, R. E., 1970: "The Deforms bili ty of Joints",
<br />De terr..ina ti on of the In-Situ Modulus of Deformation
<br />of Rock, ASTM STP 1-77.
<br />GOODMA';, R. E., HEUZE, F., BORN STEIN, A., 1971:
<br />"Numerical Analysis of Deformability Test in Jointed
<br />Rock", Rock Mechanics, Vol. 3, No. 1.
<br />HOEK, E., BRAY, J. W., 7974: "Rock Slope Engineer-
<br />ing", The Institution of Mining and Metallurgy,
<br />London.
<br />JOHN, K. W., 1968: "Graphical Stability Analysis of
<br />Slopes in Jointed Rock", Journal of the Soil
<br />Mechanics and Foundation Division, ASCE, Vol. 94,
<br />No. MS2.
<br />RITCHIE, A. M „ 1963: "Evaluation of Roc kfall and
<br />its Control", Hichway Research Record, No. 17.
<br />SEL CEPS, J. B., HAWORTH, G. R., ZAMBAS, P. G., 1971:
<br />"Rock Mechanics Research on Oil Shale Mining",
<br />Society of Mining Engineers of RIME, Preprint No. 71-
<br />AM-232.
<br />TRUDI:~:ER, J. P., 1973: "Engineering Geology of the
<br />Ka nga r_o Creek Dam", Geolo ical Surve of South
<br />Australia, Bulletin 4 .
<br />76
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