The optical fiber is used on the main parts of optical communication technique. However in recently, it is recognized that the optical fiber is having the characterizations for strain sensor. In this paper, the fundamental tests in related with the output properties for compression and tension of optical fiber were carried out and it is clarified that the relations between this output and strain of fiber is linear. Furthermore, the optical fiber is applied on the joint displacement measurement in rock mass slope. As the results, it is recognized that the displacement of joints can be measured high accuracy.

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Generally, it is said that tunnel environment is suitable for curing of lining concrete. On the other hand, enlargement of ventilating facilities is also progressing for the purpose of the improvement of work environment, and it is thought that the tunnel environment under construction is changing.
From the above viewpoints, firstly, the tunnel environment under construction was investigated and the present condition was clarified. Secondly, humidity change of lining concrete was clarified by experiment. Finally, the curing method suitable for lining concrete was proposed.

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Several effects of frequency, amplitude, cutting velocity, cutting depth and rake angle of blade on vibro-cutting properties of a blade against cement mortar were investigated experimentally. As a result, it was observed that the ratio of the principal cutting resistance during sinusoidal vibration of frequency 20Hz to that of non-vibration state decreased to be 70 to 80%. The ratio of the principal cutting resistance or the specific energy during vibration to that during non-vibration was clarified theoretically and experimentally to decease hyperbolically with the increment of the speed ratio defined as the product of the angular velocity and the amplitude divided with the cutting speed.

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Longitudinal profile of an asphalt concrete pavement in a cold region was measured weekly during winter using inertial profiler and the International Roughness Index, IRI, was calculated to analyze its seasonal changes.
The IRI of segments including cuts was greatly increased during winter and decreased to the same level as fall, when spring came. The frost penetration depth reached the subgrade at the beginning of Febrauary. The dates of the maximum IRI concentrated in the period when the maximum frost penetration depth was observed. This indicated that the IRI's increase in winter was affected by frost heave. The IRI increased with freezing index in the segments where the IRI increased largely and the IRI in the cut sections of these segments became sevral times that in fall.

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This paper describes inspection of facility effects, which were established to secure comfortableness of the driving environment. A subject of the discussion was a provisional two-lane highway that passed through mountain areas. The research adopted was the analyses of questionnaires and statistics. The facilities of Kochi-highway were evaluated using three methods in order to improve the driving environment. The methods were using the questionnaires to be answered by real drivers, users of parking areas; and the users after observing photos and videos, which showed cars running on the highway. Results clearly showed the direction and problems of measures to secure the comfortableness of the driving environment on the highways of the mountain areas.

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Various research works on rock mass classification using mechanical parameters obtained during TBM excavation has been achieved. The authors conducted a survey of the mechanical parameters on which experienced TBM operators relied most at TBM operation. Selecting the mechanical parameters based on the survey results in conjunction with TBM vibration and muck height on the muck transfer conveyor, we built a fuzzy model and developed a real-time rock mass classification system to yield rock conditions and support requirements ahead of the tunnel face. The authors applied the system on a 5m diameter TBM tunnel. 88 percent of the system output agreed with the evaluation by geologist.

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A rigid connection between the bottom slab and the side wall is adopted for a LNG inground tank currently under construction. High-density rebar arrangement is inevitable around the rigid connection due to a very complicated stress state that is caused by water pressure and earthquake induced load. High capacity prestressing and self compaction concrete made it possible to put the structure into practice. In addition, development of an analytical investigation process for RC members considering stress integration around the connection contributed its realization. Firstly the load carrying mechanism of the connection was examined with non-linear analysis to understand the effects and necessity of additional rebars in the connection. Secondly non-linear analysis was utilized for structural design at Level 2 earthquake to lower the density of rebar arrangement.

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In this paper, methodology associated with the evaluation of geotechnical risk based on finance engineering is presented. The discussion pointed out that current geotechnical risk response adopted by government bodies corresponds to risk response based on Port folio theory under the condition that numbers of public infrastructures projects are increasing, and that risk evaluation method adopting risk-return plane would be effective due to the change of construction markets. Finally, design risk of actual construction project, related to spatial variation of geometrical condition was discussed.

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This paper describes a novel approach for developing a system that extracts a crack pattern from digital images. A characteristic feature of the system is the use of an interactive genetic algorithm to optimize some parameters involved in the digital image processing. The algorithm prevents the system user from adjusting the parameters by trial and error. The user only evaluates some images produced by the system. The effectiveness of the system is verified by comparison of the results processed by trial and error and those obtained by using the proposed system.

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In this paper, for the purpose of systematizing rationally the observational design system for large scale rock cavern under high earth pressure, the generating mechanism of the loosened zone of the rock around cavern was made clear. And we investigated the estimation analysis technique which can reproduce stress change of the rock around cavern on excavation. Furthermore, the design technique and the observational construction technique which controls the occurrence of loosened zone around a cavern were proposed, and was applied to the Kannagawa power plant. And based on the measurement results on Kannagawa power plant, we verified the design technique proposed based on the real action.

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Many conventional stability evaluation methods are based on techniques and knowhows of specialist of geology and civil engineering. This paper deals with a new stability evaluation method in which the black box of the judgements by the specialists is solved and is opened. At first, the site-investigations and inspections are exceeded in object to separation-type rock fall and rock collapse at soft rock slopes along railways. Some quantification analyses using the data are also exceeded. On the base of the results, we extract a critical primary cause (CPC), which is fundamental factor in relation to slope collapses, and distill instability factors for past, presence and future. At last we present a new stability evaluation method for soft rock slopes in consideration with the above conclusions.

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Underground space is presently being used for recreation, shopping, restaurants, sports, art, and amusement, which enrich our lives, as well as for tunnels, powerhouses, and mining resources in the field of rock mechanics. Civil engineers usually design such facilities in underground space from conventional engineering points of view, i. e., mechanics. During this new century, public facilities should be designed so that people anticipate feeling great pleasure from the facilities and desire to revisit them. In order to address such anticipation during the design stage, it may be effective to employ the idea of human sensibility (Kansei). This paper discusses an approach for using human sensibility, together with rock mechanics, to design shapes for underground space.

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For large-scale underground linear structure construction projects, environmental impacts such as subsidence are major problems to be solved. So, when a project is planned and conducted, quantitative analysis method for the effects is inevitable. Also, an engineering assessment method for groundwater preservation system based on the analysis is required. In this paper, a systematic method to evaluate groundwater preservation system is proposed. This design method employs Allowable Fluctuation of Groundwater Level and allows comprehensive quantitative evaluation of impacts such as effect to existing structures and environmental impacts to underground and surface.

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The purpose of this study is to grasp the actual variation in the inflation pressure of large sized off- the- road pneumatic tires. So far the inflation pressure of a tire was regarded as in constant under operation. In this research, the variation of inflation pressure was investigated in detail for a period of five hundred days. It was observed that the variation of the inflation pressure is accompanied by the variation of the temperature near the tire carcass. Furthermore, it was verified that the variation in the inflation pressure causes changes of load capacity, profile, contact pressure distribution and form of wear. As a result, that the air pressure fluctuation could be controlled by using heat insulator between air layer and carcass. In addition to the aspect of conventional inflation pressure control, the research also involves various aspects of tire performances.

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In order to perform the optimum design considering the life cycle costs of wave-dissipating blocks which are made of coal ash, the following two topics were discussed in this study.
One is the reliability analysis for the optimum design on the stability against the waves. The field investigation, the numerical simulation and the hydraulic model test were conducted in order to evaluate the stability number of the blocks. The other is the probabilistic design of the concrete-blocks for the durability against the freezing. The freezing and thawing tests were conducted and the relative elastic coefficient were estimated in order to evaluate the life cycle costs.

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The jet grouting method is commonly used for ground improvement. However, little is known about its actual improvement structure in the ground. The extent of improvement, such as the size of effective grout diameter and the degree of overlapping is still in question, especially for complicated ground conditions such as grounds with different soil strata. This paper presents the actual findings of the condition of improved ground by jet grouting method, from a tunneling site. It was observed that preceding grout column had a near circular shape, and that they interlocked with the adjacent grout columns, hence meeting the ground improvement requirements.

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