We performed the evaluation of the cutting rate of the partial face machine by means of the rebound number test using a schmidt rock hammer. In this test, we examined the process of the cutting rate by using two types of plunger, one was a cone shaped plunger imitating of bit shape of the partial face machine and the other one was a standard shaped it. And the rebound number test using a schmidt rock hammer with a cone shaped plunger was a help to the evaluation of the cutting ratio of the partial face machine.

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This paper proposes two principles of extrinsic optical fiber sensors for civil infrastructures; and describes their prototype developments and their static/dynamic tests for future application. The first one employs a vibrating wire, and the second one employs an electric LC circuit. The tension of the wire is modulated by external force, and transformed into the change of the vibrating frequency. The oscillating frequency of the LC circuit changes as a core in a solenoid for an inductance moves. These resonant frequencies are optically detected, and transmitted through the optical fibers. The returned frequencies are dealt by a PLL circuit, with which frequencies of the driving optical pulses are adjusted as the same frequencies of the wire or the LC circuit.

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In neighboring construction by shield tunneling method. it is necessary to grasp the ground deformation and the effect to the existing structures within the execution. In this paper, the method of 3-Dimensional FEM analysis considering the excavating process was suggested first. In this analysis, shield machine, segments and back-filling material are modeled and tunnel face pressure and backfill grouting pressure are considered as load conditions. Secondly, as an example of the shield tunnel by super neighboring construction, the FEM analysis was carried out and compared with the result of the measurements.

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It is essential to use the space under narrow streets most effectively in big cities such as Tokyo.
The development of “the JIYIJU-DANMEN SHIELD METHOD”, which is a method to construct shield tunnels with non-circular sections such as elliptical, rectangular or horseshoe shapes, is under way for that purpose. As the first practical use, the Elliptical Shield Method using planetary diggers was applied to a trunk sewer tunnel under a narrow street in Tokyo.
In this paper, the design procedure of the shield machine and segments for the shield tunnel with elliptical shape is described together with experimental studies carried out to verify the said design procedure. Several important findings obtained through the actual construction are also described.

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This paper describes the field investigation on the reinfored roadbed in railway which is deceased the roadbed thickness by the new design method. After the ballast covering the roadbed surface was removed, the condition of the surface was observed under the live train, and the samples of the roadbed materials were obtained. The degree of worse in the property of the roadbed materials was compared the other test data.
As a results, it became clear that the reinforced roadbeds constructed by the new design had no problems and the new design method was rational.

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Prefabricated parallel wire strands have been adopted as the main cables of the Akashi Kaikyo Bridge, a suspension bridge with main-span of 1, 990m. These strands are fabricated at factories and bundled into a main cable at site. The tensile strength of steel wires consisting the strands is 180kgf/mm², which is 20kgf/mm² higher than that of conventional wires. Pin-plate type cable bands made of cast steel have been adopted on the bridge, in addition to the conventional groove cable bands. A new type of ropes, long-lay steel wire strands doubly coated with polyethylene and fluoric resin were introduced as the hanger ropes. These factory fabricated products are new materials with new structural forms, and surpass the past records in kinds and volume. Structural forms, materials, fabrication processes, quality control methods and inspection items of these products, parallel wire strands, cable bands, hanger ropes and other cable accessaries, are presented in this paper.

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An increasing number of bench blasting are doing in neighboring towns. We can catch the chance of making investigation into infrasound by constructing of the same kind. In this paper, by using results of data arrangement of blasting method, questionnaire and infrasound measurement, we studied about cause of complaints and method in order to reduce complaints. Then, by establishing permitted value to 100 (dB) at a certain place and by drawing expression for controlled construction of infrasound pressure level by using distance and an area of bench surface, we can construct by the fittest blasting method. And, we took regional characteristic into consideration when drawing this expression for controlled construction.

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Studies using varied approaches have been made in recent years to establish methods for evaluating the carthquake resistance of shield tunnels. Safety evaluation is not possible, however, because of a limited amount of observation data currently available on the behavior of shield tunnels during earthquakes. In this study, data collected through earthquake observation in the past 10 years were analyzed, and the validity of conditions used in the design of tunnels by the response displacement method was evaluated. A time-history analysis was also conducted modeling the ground and tunnel as a multimass vibration system. The results thus obtained were compared with the results obtained by the response displacement method. According to the findings, a method is proposed for determining the predominant frequency of ground vibration for use in seismic design.

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The characteristics of wear of rubber materials, which are used for track belts of construction machinery, were investigated by some experiments. Eight kinds of rubber specimens were subjected to the wear test, in which the rubber specimens were rubbed on eight kinds of rough terrain and the amount of wear was measured during the experiments. The results of experiments gave us some quantitative knowledge on the relationship between the wear of rubber materials and various factors such as properties of rubber material, contact pressure, roughness of the terrain and the effects of water. A method for predicting a wear life of rubber tracks of construction machinery was discussed, based on the results of the wear tests.

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Concerning the method of roadscape design in the constructive planning of highway, the evaluative examination is conducted with semantic differential method and the relation between design prosess and evaluation is analized by multivariable statistical method to prove the varidity of a method which is to make a total design concept at first and next to design the structures individually according to the concept in the first stage of construtive period.

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This report proposes the new practical method to estimate the ground displacement caused by a shield driving tunnel. This method is based on 2-dimensional FEM analysis, and not only stress release around the tail boid but also thrust by shield jacking are considered into the calculation. Then, the authors showed that it was available for the slurry shield tunnel in the stiff sandy ground.

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With the advent of modern control engineering and robotics, geotechnical centrifuge technology has reached a stage where sophisticated construction processes could be modeled in a centrifuge. Design and development of reduced construction equipment are necessary to simulate the construction processes. This paper deals with this challenge, describing problems associated with centrifuge modeling involving construction equipments, and experiences of the design and development of miniature shield machine. Validity of the design is examined and consistency of the model test results with field observation is presented.

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Most productivity improvement programs seen in the westan style management are based on the scheme finding out reality of the level of productivity of crafts and works by useing statistical approachs, like a work samplings, as the main part of the program.
The programs such as Q. C. circles found in the Jpanese management, on the other hand, have respect for human mind and aspects much greater than the statistical approachs.
It is to take account of workers opinion, idea and/or suggestions for finding out solutions to the puroblems related to the productivity improvement activities.
This study shows the new type of program combined two different schemes statistical and human approachs into one. The program can be utilized as one of the effective way of productivity improvement activities for internationl construction projects.

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In case the horizontal application of a jet-mixing method, we can not obtain a long distance and a large diameter of soil improvement. The reason is that slime discharge including air-exhaust does not work which brings increase of slime pressure in the ground and small diameter improvement. To solve the ploblems, the authors have conducted the experimental study on the new method by applying a forced slime discharger. First, the air amount necessary for effective cut was searched, then the possibility of pressure control was studied. The result of experiments both in the pressurelized tank and in field implicates that the control of air-exhaust and slime pressure is practically possible as expected.

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Up to now, many rock excavation construction methods not to use blasting are developed and put into practice, the wedge-striking bench cut method is one of which. Corresponding to the vibration and noise or loosening problem of bedrock with the construction, this excavation method is widely used. In this paper, using the stress function with finite stress concentration at the crack tips proposed by authors, a disign technique is presented for determing the percussion pitch of the present construction method. It is also confirmed by test construction.

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In order to investigate the feasibility of construction of cable-supported bridge at the site where ground condition is poor and/or air route restriction shoud be considered, the static and dynamic characteristics of both self-anchored cable-stayed bridge with relatively low tower and self-anchored suspension bridge have been discussed. The main span length of bridge considered here is about 500m because of the fact that stress resultant of main girder caused by design loads is considerably lower than its design strength in the existing cable-supported bridges of this scale. The result shows that the application of both types of cable-supported bridges to the above described site may be possible as enough static safety and economy are ensured. It has been also revealed that no problem may occur from both wind and earthquake resistant viewpoints.

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Passive earth pressure exerts a great influence on the stress and deformation of earth retaining walls in braced excavation. To calculate this pressure, conventional ultimate earth pressure equation, or Rankine-Resal's and Coulomb's equation, are currently applied respectively to cohesive and sandy soil. However, these cnventional equation to determine passive earth pressure do not adequately take into account the excavation width during work and the shearing resistance on the earth retaining wall surface.
This paper deals with cohesive soil only, deriving a calculation equation for passive earth pressure, which takes into account excavation width and the shearing resistance of the earth retaining wall suface. Then, constants in this equation are determined using the calculation results obtained from the finite element method with elasto-plastic elements. The calculation results are also compared with measured values in the model test in order to check the applicability of the calculation equation for passive earth pressure thus obtained. Finally, this paper proposes a oracticable calculation equation for passive earth pressure.

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