When applying the GPS for conventional surveying, we often encounter a serious problem, that is, the transmission waves from satellites are often disturbed by structures like buildings standings near measuring points. Thus, the measurements cannot always be possible under a condition with a sufficient number of satellites. In order to overcome this difficulty, a survey plannig system capable of predicting a proper period of time for GPS surveying has been developed in this study. In this method, any obstacle caused by existing buildings can be assessed at each measuring point by taking a photograph of a sky by a camera loaded with a fish-eye lens.

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In the case of using composite girders as main girders of a cable-stayed bridge, tensile stresses in RC slabs become problem. In this bridge, it was possible to introduce compressive stress in the RC slab by adjusting cable tennsion before and after composition with the precast RC slabs and the steel girders. These construction method in the attempt for the first time in Japan, and the practicality of these construction method was able to be confirmed by various measurements in the actual bridge.

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Ikitsuki Bridge, facing on the East China Sea, is of 3-span, continuous truss construction measuring 400m in center-span length and 800m in total length, and is coated with fluoropolymer based paint highly excellent in durability and weatherability.
This paper reviews the results of experimental studies made to evaluate the workability of the fluoropolymer based paint, such as adadptability to the airless-spray application, intercoat adhesion, touchup application method, allowable limit of salt deposition, etc.

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Discontinuous Deformation Analysis (DDA) was applied to the final design in blasting-demolition of an existing reinforced concrete structure. This paper gives an outline of the design procedure and the estimation of the analytical results for sequential change of structural system, such as falling process and final collapsed condition.

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In the case of the deterioration evaluation of concrete structures, it is essential to investigate concrete strengths and reinforcing bars in concrete.
Recently, several non-destructive testings have been generally employed for the investigation of concrete structures. These methods have such merits as that structures are not destroyed and many samples can be collected, although there exist some problems in respect to measuring accuracy.
This paper describes the feasibility study on concrete strength by the rebound hammer method and the combined method, reinforcing bars in concrete by the electromagnetic method, the radar method and the ultrasonic pulse method, crack depth by the ultrasonic pulse method and corrosion of reinforcing bars by the half-cell potential method.

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This paper reports the results of the dynamic characteristics of a floating type cable stayed bridge (length 292.1m and width 14.9m) and the observation of its dynamic behavior under the typhoon.
Microtremor measurement was performed to determine the dynamic characteristics of the bridge under construction. After the construction of the bridge, the excitation test was carried out in order to confirm its natural frequencies, vibration modes and damping constants, and the dynamic behavior of the girder and cables under the typhoon (maximum wind velocity 27m/s) was observed. From the results of the observation, wind stability of this bridge was confirmed.

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This paper presents an experimental approach for the ultimate-limit state of reinforced concrete (RC) check dam wings under impact loading of the huge rock in debris flow. At first, static loading tests were performed for the three types of specimen, i. e., the plain concrete, single and double RC cantilever slabs in which check dam wings were modeled. Secondary, horizontal impact loading apparatus was developed by using the 8 rubber hoses (1 rubber hose has 10cm diameter, 1.8m length and 16.5kgf/cm spring constant) and horizontal impact tests were executed for the three types of specimen. It was found from the static and impact tests that the cutting failure mode at the bottom surface of cantilever slab due to the crack connection is the unified ultimate-limit state of plain concrete and RC check dam wings.

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When CFRP using carbon fiber is applied instead of steel bar in the concrete structures such as piers and bridges, excellent durability is secured in marine enviroment. This paper describes about results of loading test of composite beams and forms and design procedure of the super structures of the pier. As an example of field application, a composite pier deck was built using pre-cast CFRP reinforced concrete slab as a permanent form for the steel reinforced concrete deck floor.

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An investigation of debris flow in hazardous torrent was conducted all over the country which estimated the degree of risk in debris flow. From the investigation, debris flow was evident in a lot of mountain torrents. In this study, the present evaluation on the degree of risk in debris flow was examined and the evaluation method of debris flow and hillside landslide scale which was used land as the only factor, for example, the east area of Nagasaki City that was mostly damaged by debris flow in July, 1982, were proposed.

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Usually, the process of support pattern selection relies heavily on subjective judgment based on experiences of several engineers. It is considered that these judgment processes are similar to pattern discrimination, and the selection models of support patterns for tunnel construction were prepared by using the neural network. According to the analysis of input data and the best selection of support for models, the properties and effectiveness of models were discussed. And the judgment process of neural network was pursued and the verification of the modeling were carried out.

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A numerical thermal management system for ground structure is presented. The system consists of two parts, i. e. the identification analysis of the thermal conductivity and the thermal control analysis for the ground. The former is carried out by using the nonlinear least squares method and the latter is based on the optimal control theory. The formulations of these methods are presented and they are applied to an laboratory test. A reasonable thermal conductivity of the ground is identified by parameter estimation method and the ground temperature is actually controled as illustrated by numerical and experimental study.

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The bridges that are planned across the straits on the second national expressway all have longer spans than the Akashi Kaikyo Bridge and will require foundations on the deep sea bottom or on the bedrock overlaid with deep sediments. Aseismic stability greatly influences the specifications of the foundations. This paper presents the concept of an aseismic structure for the foundations of super long span bridges based on the principle of earthquake countermeasures. In particular, we have devised a new type of foundation for the deep sea, named as a “platform”, with a weight about half that of conventional rigid caisson. The feasibility of this new foundation rests on the surveying, designing and construction technologies acquired from the Akashi Kaikyo Bridge project and on subsequent years of research and development.

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This research focuses on the issue of project risk arising from multiple projects undertaken by a single company. It has developed a risk analysis methodology to serve as a support for developing management options from company's view. The methodology is built on the work breakdown structure of a project, in which a project is defined as a portfolio of its component work packages. The concept of beta, which is a performance regression coefficient relating the performance of a work package to the overall project performance. and its use in the segment portfolio analysis, with which the risk of a construction project is measured within a homogeneous group of work packages, are the major focuses in this research.

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