The Global Positioning System (GPS) which recently has taken rapid strides is able to obtain 3-dimensional coordinates very accurately. In the GPS, only one person can perform surveying work, and in kinematic survey, among others, can complete the observation at each marking point in only a few seconds. To date, application of the GPS has reduced labor in a large number of surveying works. Most surveying conducted at construction sites is by the conventional marking-point surveying system, which requires the realtime surveying results to be attained. To eliminate this, a system in which online data can be processed through GPS-based kinematic surveying in order to obtain almost realtime measurement results was developed. Furthermore, based on this new system, a GPS-based marking point surveying system as discussed in this paper was developed.

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With a view of more intensive urban space use and improvement of living environment, much attention is now being paid to a kind of Automated Guideway Transportation called “Short Haul Transit”. This study is aimed to propose a practical method to apply Short Haul Transit systems in actual urban environment and to evaluate its effectiveness since these issues are inevitable for the progress of the technology. Based on an analysis of previous PRT and GRT type systems of Short Haul Transit, the authors set up a Model System in a performance specification form, and develop its layout design for an actual urban environment in the MM21 project, Yokohama. The effectiveness of the Short Haul Transit Model System is examined in comparison with two existing technology, bus service system and moving sidewalk system, in terms of space use, investment and service quality.

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For the shield excavation method at subway stations, slurry type three-centered shield method was developed. In this method, a double-track runninng shield machine used between stations can also be used for the shield work at the station by providing small removable shield machines, one on each side, and used subsequently for the work between stations again when these small shield machines are removed. This method is expected to promote the use of the shield method at stations because of its safety and economy.

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In order to decrease the reinforced roadbed thickness in railway, the authors performed a field investigation of the reinforced roadbed and a cyclic load test using full-sized reinforced roadbed models. The investigation proved better performance of the reinforced roadbed in field and the test did the durability of the reinforced roadbed under cyclic load. And the authors could draw a sufficient conclusion on decrease of the reinforced roadbed thickness from the avove investigation and test.

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In recent years there has been renewal of interest in blasting demolition methods of structures as more effective and safer technique at lower cost. We applied it to demolish a whole part of the reinforced concrete structure succesfully in an iron-works, under the condition that it had to be carried out without failure. The present paper describes the procedures of this actual blasting-demolition for the buildings having powerfully reinforced beams and pillars and many wall structures, including the details of palnning and design concepts and verifies its reasonableness.
Moreover we describe the analysis of the results to give instructive information with regard to necessary cares to be taken wten applying blasting techniques to reinforced concrete buildings.

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For years, the author has been engaged in enhancing the capability of construction engineering and project management, because they are the greatest management resources for construction and engineering firms. This paper gives a variety of issues such as the corporation's response to markets, functions and organizations to be built up, and assessment of project managers, as well as pointing out the need of conceptial expansion and various countermeasures in consideration of recent U. S. trends.

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This paper presents a simple practical equation for estimating the thickness of heat insulator between the inner and outer linings which is most widely used in road tunnels. To this end, using a one-dimensional tunnel-ground model, a non-steady periodic state under the condition of sinusoidal variation of air temperature in tunnel is analyzed on the basis of the thermal analysis. By using the equation presented, we can reasonably determine the optimum material of heat insulator and its optimum thickness. In addition, the equation is useful for a better understanding of the thermal characteristics of the tunnel-ground system.

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The judgement of collapse or noncollapse of cut-off slope during continuous heavy rain is extremely important upon disaster management. But, until the present time the judgement was hardly made according to the individual slope condition. The present paper in this research deals with the procedure for formulation of a system that can foretells the collapse or noncollapse of slope for every hour during continuous heavy rain using various factors, such as slope evaluation factors, time and rain together with its application to a practical slope. The authors confirm the possibility of slope judgement by the system and discuss further ambiguous issues.

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A questionnaire survey was carried out regarding the form of bridge of steel or prestressed concrete cable stayed bridge with a span about 250 meters long. By applying a theory of disaggregate behavioral model, both were evaluated with the same standard for competition. What kind of point is important in the selection of the present bridge form and what is the prediction of change for the selection probability in the future were studied. From the analysis, we could determine the need to promote research development in any problematic area.

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Statistical analyses of occupational accidents considering the variance of accident frequency rate were carried out. Emphasis was placed on the probabilistic and statistical analyses to clarify the frequency distribution of the number of accident occurrences and the time interval between accidents. From accident investigations, it was found that both the Poisson and negative binomial distributions agreed well with many actual accident cases. The frequency distribution of each of the number of accident occurrences and the time interval between accidents can be represented as a mixture of the probability distribution of the accident frequency rate and the corresponding probability distribution function. These mixing ultimately gives a negative binomial distribution for the number of accident frequency and a composite gamma distribution for the time intervals between accidents. Parameters of the distribution of accident frequency rate can be determined from actual accident data. Where such data is insufficient, the Bayesian statistical inference scheme can be employed as an alternative method to estimate the parameters of distribution.

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