Many problems to be solved happened in the duration of the completion of the stockpiling bases for crude oil. The problems encountered were analyzed by a process of “questions”, “information” “judgement criteria”, “decision making”, “reconsideration of the decisions”, “actions”, and “verification”. The problems and the decision for them are briefly summarized and reviewed in this paper. The paper also includes the characteristics of the project, including the role of the third-secter corporation, paucity of information on underground construction, and the lack of precendents in Japan.

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To develop the core-based methods for determining fracture toughness of rock under confining pressure, the stress intensity factor associated with confining pressure was calculated for CB (Chevron Bend), SR (Short Rod) and C-RCT (Chevron-notched Round Compact Tension) specimens by using a three-dimensional boundary element method.
Considering the load F₀ and the load-line displacement u_F0required to open the tip of a created fracture under a given constant confining pressure, it was shown that, if we take the load increase ΔF (=F-F₀) in place of load and take the displacement increase ΔuF (=u_F-u_F0) after the tip of the fracture is open in place of displacement, the stress intensity factor and the load-displacement diagram under confining pressure can be converted to those under atmospheric pressure.
A method for determining K-resistance (level II fracture toughness in the ISRM methods) curve under confining pressure was proposed based upon the consideration decribed above. In this method, crack length is determined first by using the slope of a linear portion in F-u_F diagram during unloading to calculate F₀ and, then ΔF and d Δu_F are calculated for unloading points to construct a AF d uF diagram, from which the non-linearity correction factor p is determined. Then the K-resistance is evaluated by using the mean p between two adjacent cycles and the stress intensity factor at the unloading point similarly to the case of under atmospheric pressure.

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According to the core-based methods proposed by the authors, fracture toughness testing under confining pressure was carried out for Inada granite and Ogino tuff by using SR and C-RCT specimens, and K-resistance curves of the rocks were measured under confining pressure up to 29.4 MPa. The surfaces of a chevron-notch were sealed with a flexible and tough bellows-shaped film of copper and vinylchloride and other surfaces with a film of vinyl-chloride. In the C-RCT specimen, a fracture propagated parallel to the weakest plane (the bedding plane for the tuff and the rift plane for the granite) while, in the SR specimen, a fracture propagated perpendicular to the weakest plane to evaluate the anisotropy in the Kresistance curve under confining pressure.
For both of the rocks, the K-resistance increased remarkably with confining pressure and the increase rate of the K-resistance with crack extension also became greater with confining pressure. Furthermore, the difference in the K-resistance between the two directions became greater with confining pressure. These phenomena were explained by the effects of confining pressure on the formation of process zone ahead of the crack tip. These effects are to reduce the tensile stress ahead of the crack tip by the component perpendicular to the crack plane, to decrease the rate of stress intensity factor with respect to crack extension by the same component of the confining pressure and to close pre-existing microcracks by the components parallel to the crack plane.

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A series of numerical experiments on the failure process of homogeneous rock slope has been performed using Boundary Element Method and Displacement Discontinuity Method, and then the effect of initial rock stress on the stability of homogeneous rock slope has been discussed.
Firstly, the distribution of tangential stress along the surface of rock slope has been analysed and the condition of fracture initiation has been formulated. The stability factor at the fracture initiation.of rock slope is affected by not only the slope angle and the rock strength but also the initial rock stress. Increasing the ratio of horizontal to vertical stresses at the pre-excavation, the value of the stability factor decreases and the location of fracture changes from the toe of slope to the upper surface.
Secondly, failure process of rock slope has been analyzed on the basis of the Fracture Mechanics. It is made clear that the failure process and the failure mode are also affected significantly by the initial stress state as well as the rock strength, the frictional characteristics of the crack surface and the slope angle. Furthermore, it is pointed out that the critical value of the stability factor is rather independent of the initial stress state.

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In this paper, a three dimensional measuring system based on multi slit lights and the stereo visionwas proposed. The most important problem in the stereo vision is to find out the corresponding points from two images automatically. In this proposed system, the light source was devised to obtain the corresponding points automatically and quickly. Consequently, it was confirmed that the time required to measure the object shape was much reduced compared to some methods proposed previously. In the shoveling task, the working robots need to have an ability to recognize the shape of object such as a huge rock pile in a short time. Therefore, it can be considered that this system is useful for the vision of working robots in the underground excavation field.

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A laser spray coating system comprising of a spray nozzle was used to atomize titanium-metal feed-wire and inject thus produced TiN droplets into a stationary bath of liquid cryogenic nitrogen. The cryogenic-bath rapid-solidification approach allows achieving nonequilibrium microstructure as well as reducing the size of atomization chamber and minimizing environmental contamination of the product.
Spherical TiN powders recovered in liquid N₂ could be separated into two types of powder by decantation. Coarse particles vary from 10 to 200μm and fine powders are smaller than 10μm. The spherical TiN powder contains over 30 at % of nitrogen resulting in the composition of N deficient TiN (consisting of TiN and TiN_0.3).

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The extraction of vanadium (V) from sodium hydroxide solutions by trioctylmethylammonium compounds (R₃R'NCl and R₃R'NOH) in benzene has been investigated under different conditions. As a result, it is found that vanadium (V) is taken up from alkaline solutions through anion exchange reaction by the following equation:
V₂O^4-₇ (aq) + 4R₃R'NOH (org)-(R₃R'N) ₄V₂O₇ (org) + 4OH^- (aq).
The formation of the species, (R₃R'N) ₄V₂O₇, is supported by the fact that the characteristic vibrations of moiety appear in the infrared spectrum of organic extract. In addition, when the extraction of vanadium (V) has been also examined by using trioctylmethylammonium salts, replaced by various anions such as NO^-₃, SCN^-, HSO^-₄ and ClO^-₄, in comparison with the results by R₃R'NCl and R₃R'NOH, the extraction efficiency of quaternary ammonium salts for vanadium (V) is in the order OH^->Cl^->HSO^-₄>NO^-₃> SCN^- ≥ClO^-₄.

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Complexation behaviors of phosphoric acid esters with cobalt (II) and nickel (II) in solvent extraction have been assessed to elucidate the relationship between the structure of phosphoric acid esters and the extraction phenomena. By using phosphoric acid esters with aryl and alkyl groups, it is concluded that the structure of the organic groups in the phosphates plays an important role in the formation of the complexes and the extraction behaviors. In the case of di (nonylphenyl) phosphoric acid, the octahedral complexes of cobalt (II) and nickel (II) form in the extraction, and the compound extracts the metal ions at the lowest pH among the phosphates used. By changing the phenyl group with an alkyl group, the extraction curve shifts to higher pH, and the formation of the tetrahedral complex of cobalt increases in the extraction. Furthermore, the increase of the steric hindrance of the alkyl groups in the phosphates causes the shift of the extraction curves to higher pH. In addition, the selectivity of cobalt over nickel increases with increasing the steric hindrance of the phosphates.

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To examine the feasibility of electrolytic reduction of Cr (III) to Cr (II) using a titanium cathode, cathodic polarization characteristics of Cr (III) on a titanium cathode and batch-type electrolytic reduction of Cr (III) using a bipolar electrolytic cell were investigated with acidic aqueous solutions of CrCl₃ and Cr₂ (SO₄)₃. The reduction of Cr (III) to Cr (II) started at a cathode potential of about-0.7V vs SHE, and the reduction current of Cr (III) increased with a decrease in cathodic potential. The reduction current in CrCl₃ solution was greater than that in Cr₂ (SO₄) ₃ solutions under the same conditions. However, in CrC1₃ solutions, a remarkable decrease in the reduction current was observed at around-1.2V vs SHE, because of the hydrolysis of Cr (III). In the batch-type electrolytic reduction of Cr (III) using a bipolar electrolytic cell, complete reduction of aqueous 0.5-1.0kmol m^-3 CrCl₃ solution with a current efficiency of 70-50% could be achieved by keeping the catholyte pH at 2, to avoid hydrolysis of Cr (III). When using Cr₂ (SO₄) ₃ solutions, the reduction of Cr (III) proceeded almost as fast as using CrCl₃ solutions, at the same condition. Since the hydrolysis of Cr (III) is less significant in Cr₂ (SO₄) ₃ solutions than in CrC1₃ solutions, the electrolytic reduction process can be operated at a higher current using Cr₂ (SO₄) ₃ solutions. KEY WORDS: Electrolytic Reduction, Chromic Chloride, Chromic Sulfate, Bipolar Electrolysis Cell

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The distribution of zinc cation between crystallographically nonequivalent positions in ZnFe₂0₄ has been determined by anomalous X-ray scattering near the Zn K absorption edge. Measured intensity ratio with two energies close to the edge can be quantitatively explained only by assigning all zinc cations to the tetrahedral position in the approximately cubic close packed array of oxygen ions. A similar conclusion has also been reached for Zn_xFe_3-xO₄ solid solutions with x=0.73, 0.54 and 0.35 employing the improved X-ray method. This is consistent with the EXAFS results which indicate an almost unchanged environmental structure around zinc cation in these solid solutions.

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