The authors have developed 3D analysis computing program for the coupled FS-DD method which considers joint slip and joint separation. In order to confirm the applicability of the developed methods, the model of rectangular prism excavation beneath the horizontal joint and the model of the large underground excavation (Super Kamiokande) was used as a numerical example and a case study, respectively. In this paper, the numerical procedure and the analyzed result of the numerical example and the case study are presented.

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A constitutive equation formerly proposed by Okubo et al for one- and two-dimensional analysis was extended to the three-dimensional. The constitutive equation was developed on the basis of the non-linear visco-elastic theory, and it was successfully applied to one- and two-dimensional problems such as long-term stability of circular tunnel. In the three-dimensional analysis, a constant volume-modulus was assumed, and analogy with equations by Levy-Mises and Prantl-Reuss was discussed theoretically. Comprehensive FEM analysis simulating constant-strain compression tests was carried out with tetrahedron, prism or brick elements changing number of elements, confinement of specimen ends, coefficient of variation of strength for each element and loading rate. The simulation was performed beyond the peak strength and the complete stress-strain curves were obtained for all cases. The three-dimensional results were analogous to the two-dimensional and conformed to the experimental results. For example, the peak and residual strengths were found to increase with loading rate.

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Sprayed steel-fiber reinforced mortar (SFRM) or concrete (SFRC), one of the future promising composite materials, is considered to suit today's rapid excavation by a tunnel boring machine, a boom header or a continuous miner. In this study, four-point bending tests were performed measuring load and deflection in the air-dried condition. The pre-failure characteristics such as Young's modulus did not change so much. However, the residual strength increased dramatically in behalf of the steel-fiber reinforcement. The peak strength at steel-fiber content of 1.5 % became twice as much as that of plain mortar. The experimental results in bending together with the results of uniaxial tension and compression tests were analytically examined and discussed. It was found that the peak strength in bending was strongly correlated with the residual strength in tension. An equation to estimate the peak strength in bending was proposed and the calculated results were compared with the experimental results.

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Recently, for the concern of safety in construction as well as for environmental and economical reasons, an efficient small-diameter shallow tunneling method has become increasingly important for outside plant engineering such as water supply, gas, electricity and telecommunications. In particular, for construction work near existing facilities, an underground tunnel excavated by the pipe jacking is becoming increasingly popular to avoid adverse effects. Basically, the pipe jacking system involving the pushing or thrusting of the drivage machine through concrete pipes ahead of jacks. The method utilizes the mud slurry which is formed around the pipes for stability of surrounding soil. The Japan Sewage Association proposed empirical prediction equations of the thrusts in using the pipe jacking method. However, these prediction equations are not accurate. From this point of view, the major purpose of this study is to find the way to predict the thrusts in using pipe jacking. In pipe jacking, the performance of the mud slurry plays an important role in the pushing process. The thrusts in pipe jacking can be predicted well by using the initial thrusts and the resistance between the mud slurry and concrete pipes.

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The purpose of the present study was to develop a mathematical model for effective operation of a longwall working face in an underground coal mine. The model can evaluate the relationship between operating efficiency and working height of the face in a coal seam. The results show that, contrary to a common thought, the working height of the face must be 20-30 % lower than the thickness of the coal seam. As a consequence, low-grade coal near the bed and roof rock remains in the coal seam. The results of this model enable effective operation of the working face and maximum profit in a mine.

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The reaction mechanism in synthesis of ultramarine blue with kaolin, sulfur, sodium carbonate, silica and rosin was investigated by a thermal analysis, a powder X-ray diffraction analysis and a Raman scattering. The mixture of the raw materials was calcined at 820 °C for 5 hours (heating rate：0.1 °C/min.) to form the ultramarine green, which was the intermediate products of the ultramarine blue. The ultramarine blue was finally prepared with the oxidation of the ultramarine green at 500 °C. In the calcination process, the sodium sulfides were generated by the reductive reaction of sodium carbonate, sulfur and rosin at 400∼500 °C, and the NaAlSiO4 was formed by the synthesis of anhydrous amorphous kaolin and the sodium sulfides at about 600 °C. And, the ultramarine green begun to form at near 700 °C with the reaction of the NaAlSiO4 and the sodium sulfides. In the oxidation process, the sulfur atoms was generated from the oxidation of the sodium sulfides which excessively existed in the ultramarine green, the sulfur atoms transformed the (S2-) ions of the ultramarine green into the (S3-) ions. And these reactions caused the ultramarine green to convert the ultramarine blue. The lattice parameter of ultramarine green was increased during the oxidation.

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An appropriate amount of sodium hydroxide solution was added into a ferric sulphate solution kept at a temperature of approximately 90 °C in order to have the resultant solution ajusted pH of about 2.0. The solution was maintained at this temperature for 240 hours kept agitated, and the hydrolysis reaction was allowed to be made. The hydrolysis product was single phase and it was estimated to be sodium jarosite-type compound of Nax(H3O)1-x[Fe3(SO4)2(OH)6] in which H3O is being combined in the form of the solid solution. Since it was conceived that (H3O)[Fe3(SO4)2(OH)6] was possible to dissolve easily into a high temperature sulphuric acid solution, a 75 g of the compound thus obtained was added into the solution containing sulphuric acid of 50 g/l kept at a temperature of approximately 90 °C. After the extracting treatment of the compound for 48 hours, sodium jarosite was obtained in the close to pure form containing the decreased amount of H3O[Fe3(SO4)2(OH)6] . The solubility measurements of sodium jarosite prepared by the above procedure in sulphuric acid solution of various concentrations were carried out at temperatures of 70, 80, 90, 100 and 110 °C.The results obtained were as follows:1. with the individual temperatures, the ferric ion concentration increased with increasing the sulphuric acid concentration in the solution.2. The concentration of the ferric ion dissolved into a sulphuric acid solution with the same concentration decreased with increasing temperature.3. The relationship between the sulphuric acid concentration and the ferric ion concentration at temperatures of 70, 80, 90, 100, and 110 °C is expressed with the empirical formulas.

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In order to clarify the behavior of minor elements in the oxidation zone of the QSL lead smelting process, the distribution ratio of the impurity element M (M = Cu, Ag, As and Sb) between the metallic lead phase and the PbO-FeOx-CaO-SiO2 or PbO-FeOx-CaO-SiO2-ZnO slag phase, as defined by LMS/Pb = (mass % M in slag)/[mass % M in lead], was investigated at 1,423 K. It was found that the iso-LMS/Pb lines of Cu, As and Sb for the PbO-FeOx-CaO-SiO2 slag with Q (mass % CaO/(mass % CaO + mass % SiO2)) = 0.4 in the PbO-FeOx-(CaO + SiO2) quasi-ternary composition diagram were almost parallel to the axis of the PbO composition in the range of the FeOx mole fraction less than 0.5 while the iso-LMS/Pb line for silver at a given PbO composition represented a tendency to increase with the FeOx content of the slag. The distribution ratios of As and Sb were found to increase with increasing Q from 0.3 to 0.4 while those of Cu and Ag decreased. It was clarified that the addition of ZnO to the PbO-FeOx-CaO-SiO2 slag did not give any serious effect to the distribution ratios. By using the determined LMS/Pb, the Raoultian activity coefficients of CuO0.5, AgO0.5, AsO1.5 and SbO1.5 were derived for the PbO-FeOx-CaO-SiO2 slag and they are 12, 1.1, 0.9, and 18 for the slag with NPbO = 0.1 and Q = 0.3 and 14, 3.4, 0.3 and 2.4 for the slag with NPbO = 0.1 and Q = 0.4, respectively. Based on the obtained LMS/Pb, the fractional distributions of As and Sb between the metallic lead, slag and gas phases were evaluated thermodynamically, and it was found that the fractional distribution in the slag phase increased drastically with increasing lead content of the slag.

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The phase equilibrium between the MgO saturated FeOx-MgO-SiO2 slag and Ni-Fe alloy was investigated in the oxygen pressure region from 3 × 10-5 and 3 × 10-2 Pa at 1,673, 1,773 and 1,873 K to analyze the nickel smelting processes. The effect of CaO addition on the phase relation between the same slag system and Ni-Fe or Ni-Cu-Fe alloy were also studied at 1,673 and 1,773 K. The following experimental results have been obtained in the present study. The MgO solubility in the FeOx-SiO2 slag decreases with decreasing SiO2 content and temperature and also by the addition of CaO. However, there is no significant difference between the MgO solubilities in the slag equilibrating with the Ni-Fe or Ni-Cu-Fe alloy. The distribution ratios of nickel and iron between the MgO saturated FeOx-MgO-SiO2 slag and Ni-Fe alloy phases at log pO2 = -8 and 1,773 K are almost 0.01 and 1, respectively. These values increase with increasing the oxygen pressure and decreasing temperature. These indicate that nickel condenses mainly in the metal phase while iron is distributed in both the slag and metal phases. The CaO addition to the MgO saturated slag depresses the distribution ratios of nickel and iron in the slag phase. Comparing the distribution ratio of nickel equilibrating with the Ni-Fe or Ni-Cu-Fe alloy system, the increase of nickel dissolution in the slag equilibrating with the metal phase containing copper is mainly attributed to the change in the activity coefficient of nickel in the alloy phase. The values of 3 and 7 are estimated as the activity coefficients of NiO(s) and CuO0.5(l) in the MgO saturated FeOx-MgO-SiO2 slag at 1,773 K. The activity coefficient values increase with the addition of CaO in the slag. Thus, the dissolution of nickel and copper in the slag has been thermodynamically evaluated to decrease with CaO addition.

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Silica particles of 5μmφ were arranged on CaTiO3 substrates by the drawing and the developing steps, as reported in a previous paper. Fixing treatment is necessary to repeat the arranging process to produce the three-dimensional micro-structures. A thin film of fluoride polymer was formed on the substrates after the particle arrangement to fix the arranged particles. The effects of the fixing treatment on the arranged particles and the arranging process were investigated. The following results were obtained. (1) Electrified patterns are formed on the substrates with an electron beam scanning in the drawing step. More sharp patterns are obtained by preforming the thin film of fluoride polymer on the substrates. This improvement is due to suppression of surface diffusion of the electrified charges by the film. (2) The particles are arranged by the electrostatic force in the developing step. Since the electrified pattern is sharp, better particle arrangement can be obtained by preforming the film on the substrates. (3) The film holds the adhered particles through the second time drawing and developing steps and the arranged particles are scarcely affected by the fixing treatment. These results suggest that the formation of thin film of fluoride polymer is effective for the fixing treatment and that three-dimensional micro-structures can be produced by the particle assemblage

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