We present the case for information technology to support the design, construction, and operation of capital projects through the concurrent and integrated use of formal and visual computer models of the physical project scope, the organization carrying out the project, and the process that will deliver the facility. We call this approach to design and manage a project Virtual Design and Construction. We review several commercial and research prototype software tools that provide some of the functionality needed for Virtual Design and Construction and summarize benefits firms are achieving today from the use of these tools.

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The authors had been taken notice of durability of high-strength friction grip (HSFG) bolted joints in steel bridges and investigated bolt tensions and slip coefficient in existing bridges. As results, existing bolt tensions were decreased more than they expected and had more variation.
Then in order to make clear the limit states, the experiment using testing girders and FEM analysis of HSFG bolted joints considered the reduction and the variation of bolt tension were carried out. As results, the influence of reduction and variation of bolt tension on slip strength are clarified, and the ultimate limit state after slip of HSFG bolted joints is supposed.

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In order to extend the applicability of rock-liner for TBM construction, rock-liner with concrete (RC rock-liner) was developed. The purpose of the present study is to establish the rational design method for RC rock liner. As part of the purpose, the loading tests with full-scale model were conducted for obtaining the mechanical properties of segment in RC rock liner. Furthermore, the present study employed a former RC design method by regarding the main-girder as steel bar, and its utilization was confirmed by comparing the experimental data.

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This paper presents the simplified numerical method for predicting the behavior of ground heave and existing tunnel due to open cut. This method uses Steinbrenner's form considering the strain level-dipendency of deformation modulus of ground to calculate the ground deformation and stress, and the beam model supported by ground springs to calculate the deformation and section forces of the tunnel. These calculations are verified by comparing with 3-dimensional finite element analysis and field measurements. Regarding monitoring of existing tunnel during open cut, this paper shows that the numerical method for calculating the real-time section forces of the tunnel is verified by comparing with shell finite element analysis.

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Many conventional stability evaluation methods are based on techniques and knowhows of specialist of geology and civil engineering. In this paper, we 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 both of downfall-type rock fall and separation-type rock fall/rock collapse type at hard rock slopes along railways. Some quantification analyses using the data are also exceeded for each of the both types. On the base of the results, we extract a critical primary causes (CPCs), which are fundamental factors in relation to hard rock slope collapses, and distill instability factors for past, presence and future. At last we present a new stability evaluation method for hard rock slopes in consideration with the above conclusions.

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Concrete pieces falling from tunnel lining are extremely dangerous for highway traffic. The purpose of this study is to quantify the danger of exfoliation of concrete fragment. Crack condition of lining concrete in 7 tunnels was investigated in order to obtain the fundamental properties of exfoliation. Cracks in lining were defined as 3 types by its directions, and investigated cracks were categorized by these crack types. The influence factors on exfoliation are investigated from various crack data.

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The occurrence of a large earthquake has a great impact on sustainability of the enterprise and stability of the business administration. For the enterprise with its own equipment, hence, it is important to manage the seismic risk properly. In this study, earthquake insurance, which is a basic measure of risk transfer, is handled. An evaluation method is shown in which the amount of risk transfer by the insurance is determined considering the degree of the impact the earthquake has on the corporate finance, from the viewpoint of the executives implementing risk management. In the study, the standard deviation as well as expectation of seismic loss for risk hedger is evaluated based on a scenario earthquake.

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Big scale construction machinery is absolutely necessary for the mineral resources development and various construction works. Troubles of the machinery give serious losses in the efficiency of operations and also in financial proceeds. From a practical point of view, we employed a wavelet transform with Gabor function as a window and analyzed the acceleration wave curves data to detect a misfiring cylinder from the multi-cylinders diesel engine. The results by wavelet analysis revealed that the misfiring cylinder could be detected visually in time-frequency maps. With the aid of statistical analysis using rms value, the misfiring cylinder of multi-cylinders diesel engine can, therefore, be doubly checked by wavelet analysis.

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This paper proposes the durability assurance methods of shield tunnels for transmission which are assembled by reinforced concrete segments based on the degradation analysis of existing shield tunnels for transmission. The main features of these methods are the following three points.
First, we group the environmental conditions of these tunnels into seashore and inland atmosphere. Secondly, we propose thickness of minimum concrete cover to reinforcement of segment under both environmental conditions. Thirdly, we propose the allowable crack width against both environmental conditions to control cracks caused by bending force of the segments against the permanent loads.

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A main character of the new construction method is that box culverts constructed mutually connect steel-elements by special type of joints. This study is for the purpose of investigating the final connecting part of this structure. The final connecting part has to be able to adjust an error of a regular situation and make ease connecting work in a narrow space. According these condition, this final part design reinforced concrete with Close-shaped Bar Lap Splices. This paper estimates the flexural strength of beams with Close-shaped Bar Lap Splices. And the strength of this splice is formulated based on several basic studies.

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In the case that an explosive load is subjected in a borehole which has been excavated in the ground, the soil around the borehole wall will be abruptly compressed and then a cavity will be created in the ground, being surrounded by the compressed soil wall. When we apply this idea to the construction of tunnels or foundations, the underground space can be created with the minimum mucking and the reduced lining. We discuss the possibility of the underground space construction by the explosive loading through some numerical simulation and experiments.

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In case that uderground diaphragm walls are used as permanent structures, the connections between diaphragm walls and reinforced concrete floor slabs must be rigidly connected. Although the design method of the connections for conventional reinforced concrete diaphragm walls has been well established, the method for steel-framed diaphragm walls has remained unclear. Therefore, an experimental study has initiated. Through the results of real size tests, it was understood that the connections had proper strength and deformation capability. The design method and appropriate detailing of the connections for steel-framed diaphragm walls was also proposed in this paper.

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In the case that an explosive load is subjected in a borehole which has been excavated in the ground, the soil around the borehole wall will be abruptly compressed and then a cavity will be created in the ground, being surrounded by the compressed soil wall. When we apply this idea to the construction of tunnels or foundations, the underground space can be created with the minimum mucking and the reduced lining. We carried out some laboratory experiments and field ones, where small boreholes were expanded by blasting. The results of the experiments gave us some knowledge on the possibility of the underground space construction by this idea.

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The authors developed a new aseismatic reinforcing method for existing RC columns in order for easy and quick maintenance work in daily and emergency inspections after earthquakes. In this new method, manufactured spiral tendons bind precast concrete blocks around the columns. In order to confirm the aseismatic performance of the new method, we conducted cyclic loading tests using 5/8 scale model columns. These tests demonstrated that the new method have more ductility and enable easier visual inspections than the conventional methods and is an effective aseismatic reinforcing method for the existing RC columns of rigid-frame railway viaducts.

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Sewage Water Pipe Jacking has not been used to the pipe of which internal diameter is larger than 3.0m so far. Because Road Traffic Control Law restricts the height of transportation after casting at pipe manufacturers in Japan. On the other hand, pipe jacking method is most profitable among urban tunneling methods. Therefore, if the pipe diameter restriction is overcome technically and larger pipes are applied widely, construction cost of urban tunnels can be reduced contributively.
This paper describes a developed method that halved casting pipe can make easy transportation and the segments can be combined as a perfect pipe by post tensioning around a launch shaft And the application is examined on the structural point through basic performance tests. As a result, the capacity is obtained as the standard pipes specified by JSWA.

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Recently, tomographic analysis has been applied to the seismic refraction survey for tunnel geological investigations. In tomograpic analysis, it is important to use appropriate initial velocities. Therefore, 5 methods to set initial velocities were examined by using geological observation records at the tunnel face. The results showed that slight difference in a coincidence with geological observation records was recognized among tomographic solutions leaded by the 5 setting methods. However, the tomographic solutions by initial velocities setting method from 2 simple travel time analyses showed well coincidences with the geological observation records. In this paper, we report the problems and setting methods of the initial velocities in tomographic analysis.

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