The number of students applying to construction firms is currently decreasing, raising concern for why people do not gather easily in the construction industry. In this research, the hypothesis that “report in the media” influences the problem is proposed and is verified by executing the contest analysis of newspaper and giving questionnaire surveys to students. As a result, the influence of “report in the media” was not observed. [This abstract is not included in the PDF]

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       The number of students applying to construction firms is currently decreasing, raising concern for why people do not gather easily in the construction industry. In this research, it set up a hypothesis that “university education” and “recruitment activity of construction firms” influences the problem, and it verified by interview to construction firms and giving questionnaire surveys to students. As a result, the influence of “university education” was not observed, but the influence of “recruitment activity of construction firms” was observed. [This abstract is not included in the PDF]

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       This experimental research work was conducted to determine how combining different recycled materials in concrete would affect the mechanical and environmental performance. Results were given in terms of environmental performance indicators, which weight the mechanical performance by the environmental impact. It was found that replacing high volumes of Portland cement with fly ash, which significantly reduces CO2 emissions, improved the environmental performance. The benefit of replacing normal aggregates with recycled aggregates could not be clearly seen, as these materials have similar CO2 emissions. [This abstract is not included in the PDF]

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       This experimental investigation was conducted to determine the effect of fiber type and mixing proportion on the strength and durability of fiber-reinforced mortar with fly ash. The compressive strength was not significantly affected by sand-binder ratio, but flexural strength increased as sand-binder ratio increased. Increasing the volume of fly ash resulted in a decrease in compressive and flexural strength, flexural toughness, and air permeability, but this result may be attributed to the slow curing speed of fly ash. Polypropylene and recycled fiber mortars exhibited similar behavior. [This abstract is not included in the PDF]

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       In this research, basic properties and repair effect of an emergency retrofitting method using TST-FiSH (Fiver Sheets containing Hydraulic-resin) was investigated. From the results of bond test, it was identified that the fiber sheets with 300g/m² fiber content have a higher bond capacity. It was also found that this bond capacity is achieved when the resin concentration is 66%. The Carbon, Aramid, Vinylon sheets were further experimented and were found that all sheets improve the load bearing ability in repairing of damaged concrete. [This abstract is not included in the PDF]

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       The construction process greatly influences the quality of structural concrete, so it is necessary to improve the inspection method of the process. This research aims at the establishment of an appropriate concrete acceptance inspection for the quality assurance, and examined stiffening behavior and fresh properties. As a result, the influence of environmental condition on compressive strength and air permeability is different. By changing the fineness modulus, sand-aggregate ratio, and unit water content, the utility of the tamping test became clear. [This abstract is not included in the PDF]

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       Premature deterioration of concrete structures may be caused by cracks which lead to the corrosion of reinforcing steel. In this research, carbonation was assumed to be the primary cause of steel corrosion, and the effect of cyclic dry-wet conditions on the progress of carbonation from the crack was investigated experimentally. It was found that carbonation progress was difficult under cyclic dry-wet conditions as set in this experiment. However, when the crack reached the reinforcing steel, carbonation would advance considerably along the length of the steel-concrete interface. [This abstract is not included in the PDF]

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       Reinforcement corrosion of concrete structures is investigated by the non-destructive techniques. Investigated electrochemical parameters, i.e. half-cell potential, polarization resistance and concrete resistance are used to amount the corrosion rate. Above parameters are combined by theoretically developed methods to calculate the macro-cell corrosion rate. The results show that the calculated currents by theoretical methods represent the behaviour of macro-cell corrosion compared to half-cell potentials only. However, they are not matching when the polarization resistance is taken into account. None of the method show a similarity with the macro-cell current measured using a segmented steel bar. [This abstract is not included in the PDF)

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       Segmented steel bar was used to study the behavior of macro-cell corrosion of steel reinforcement in concrete. In this research, embedded steel bars were made with different lengths of steel element such as 15 and 60mm. The aim of this paper is to identify the effective length of steel element for macro-cell corrosion by comparing the macro-cell corrosion current densities obtained from these above specimens. According to the result, 15mm- element steel bar is recommended for effective length of steel to study on macro-cell corrosion. [This abstract is not included in the PDF)

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       Half-cell potential is frequently used to investigate the steel corrosion of existing RC structures. However, when the macro-cell corrosion is generated the potential of cathode is affected by anodic reaction and hence correct corrosion potential from the direct measurements cannot be obtained. In this research, the effect of macro-cell corrosion on measured half-cell potentials was experimented using both continuous and segmented steel bars. The effect of anodic reaction on the measured potential of cathodic area was observed in the results i.e. the significantly negative half-cell potentials were observed in the regions with no chloride. Additionally, it was found that the corrosion rate changes depending on the area ratio between anode and the cathode. [This abstract is not included in the PDF]

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       The results of a test are presented in which concrete specimens treated with different water repellent agents have been exposed to cyclic seawater shower for one year. The objectives of the test were to examine the effectiveness of water repellent treatments as a chloride barrier for cracked or un-cracked concrete under marine environment. The test results indicate clearly how cracks in concrete influence the effectiveness of water repellent treatment as a chloride barrier. It is concluded that a careful assessment of cracks in reinforced concrete structures before a water repellent treatment is very important to determine the most appropriate application technology. [This abstract is not included in the PDF]

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       This paper reports the long-term durability of super lightweight aggregate (SLA) concrete in marine environment. In addition, the effect of segregation on the performance of SLA concrete was investigated. After 8-year exposure in marine environment, various tests and investigations were conducted. It was revealed that SLA concrete has enough compressive strength and Young’s modulus after the long-term exposure. The diffusion coefficient of chloride ion of SLA concrete was small because of its low water to cement ratio. Though the segregation slightly affects the performance of SLA concrete, it was verified that SLA concrete has high durability in marine environment. [This abstract is not included in the PDF]

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       Local subsides or cave-in’s of the ground often occur in urban area. The complicated underground situation as well as the necessity of urgent restoration do not usually allow full investigation for the real cause. The detailed mechanism of the phenomenon has not been, therefore, well understood.
   Cave-in is usually initiated by the formation of cavity in the ground due to soil loss. When the location of the cavity is deep in the ground, the detection of the cavity is not easy. Then it is possible that the hidden cavity expands for a long time to eventually cause sudden large-scale collapse. In this study, characteristics of formation/expansion of cavity and surrounding ground loosening are investigated, aiming at effectively indicating dangerous pattern of cavity and loosening. [This abstract is not included in the PDF]

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       Damaged old sewer pipes are known to often cause void/cavity or loosening in the surrounding soil, which may lead to a cave-in in the road. In this research, in order to understand the mechanism and governing factors of cavity formation/expansion in the ground, a series of model tests simulating flowout of soil through a crack/gap in a buried pipe was conducted.
   It was found that a cavity and surrounding loosening in the ground can extend rapidly upward when the ground consists of poorly graded sand, especially when it is fully saturated. Quantitative evaluation was also given to the loosening around a cavity. [This abstract is not included in the PDF]

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       A new technique of ground improvement by the microbial function has been recently proposed, in which soil cementation can be generated by adding calcium, nutrient and microbes into soil. Metabolic function of microbes produces carbon dioxide, which helps to generate calcium carbonate. In this study, a series of trial tests was conducted in order to evaluate the degree of soil cementation generated by those function in loose sand, using the measurement of shear wave velocities transmitted in a specimen. [This abstract is not included in the PDF]

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       The climatic variations sometimes entail changes of properties of soil. These changes are observed at microscopic scale and they are evident on the basic properties which directly affect the physical and mechanical properties of soil. In most cases, these alterations depend on the infiltration process which is not a continuous process. When rainfall starts, water infiltrates soil and matric suction decreases but when rainfall stops, soil dries and matric suction can recover, thus the soil undergoes repeated short wetting — drying cycles in which the matric suction varies. As consequence of these cycles, the strength of soil could change and a noticeable increment in deformations can be presented.
Due to this phenomenon is not completely clarified, a series of triaxial tests have been carried out when the material is subject to wetting — drying cycle. During this process Bender Element (BE), Trigger Accelerometer (TA) and cyclic loading by using Triaxial Compression (TC) have been performed in order to understand the internal changes of the material. [This abstract is not included in the PDF]

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       A series of unconfined compression tests was conducted on lime treated soil with short period of cure. Lime treated soil was produced in a recycling plant, using surplus soil from construction sites. Specimens with different initial water content were cured in various conditions; being submerged in the water, being kept in the air and being put in a plastic bag to keep water content constant. Obtained unconfined compression strength was mainly governed by current and initial water content, rather than time length of cure. [This abstract is not included in the PDF]

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       Cohesion value in the sandy soil is often neglected in geotechnical design as a conservative approach. However, recent work has shown that the stability of foundations and slopes can be considerably influenced and enhanced by the presence of even small amount of cohesion. Understanding the behavior of cemented soils under static and dynamic loading conditions is thus of significant interest to geotechnical engineers. To some extent, taking the advantages of those behaviors may reduce the construction cost of temporary or permanent earth structures.
   In this study, cohesion value was evaluated on lightly cemented sand in a series of drained triaxial compression test. Relationship between the degree of cementation and isotropic consolidation stress is also discussed. [This abstract is not included in the PDF]

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       The structural response of flexible buried pipes has been long investigated. Most of the previous studies mainly focused on the response of flexible pipe under static loading. The long-term behaviour of flexible pipe subjected to cyclic loading has not been fully understood. In this research, experimental study has been conducted to examine effects of backfill soil condition on the behaviour of flexible buried pipe under cyclic loading, using a large soil chamber. [This abstract is not included in the PDF]

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       Extensive damage of sewage pipes was caused by past large earthquakes such as the 2004 Niigataken-Chuetsu earthquake. Typically, their uplift was induced by liquefaction of backfill soils, and several measures have been taken against it. Since the solidification method as one of the countermeasures still needs to be studied from a view point of the long term mobilization of sufficient strength, a series of unconfined compression tests was conducted on a lime-treated waste soil. Under the test conditions employed for the current study, strength reduction was observed at the initial stage of curing under water, which was followed by rather a stable strength mobilization up to 1 year of curing. [This abstract is not included in the PDF]

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       Nowadays, big earthquakes, such as the Tokyo Inland Earthquake are considered to occur in the near future and their effects on Japanese economy may become very large. The authors focus on the 1995 Kobe Earthquake, and make the function of changing rate of land price before and after the earthquake. And they have analyzed the land price influenced by the earthquake. In 1996, soon after the 1995 Kobe earthquake, in the area with higher structural damage ratio, land price decreased more and in 1997, decline of the land price stopped in the areas where the rate of complete failure and burned out is high, on the one hand, it continues declining where the rate of partially damaged houses is high. From the 3rd year since the 1995 Kobe Earthquake, land price in the areas with high complete failure and burned out ratio came to rise, however, in the areas with high partially damaged ratio, land price didn’t rise. It is considered that this trend is made by difference of recovery and reconstruction. [This abstract is not included in the PDF]

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       Education for disaster reduction in a compulsory education course is very essential to give disaster response capacities for all the children who will grow up to be politicians, administrative officers, researchers, engineers, mass media people, etc. This study aims to survey current educational activities for disaster reduction in order to develop a better curriculum in a compulsory education course. Advanced educational activities for disaster reduction in elementary schools and junior high schools were collected and its tendency was analyzed using children’s activity flows after a disaster. [This abstract is not included in the PDF]

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       The authors have analyzed “Standing Orders on Disaster”, which is the basic plan to implement the disaster management operations in Bangladesh, and compared it to actual operations performed during and just after the Cyclone Sidr in 2007. Information on actual operations were collected by the authors and researchers in Bangladesh University of Engineering and Technology (BUET) based on briefing papers at that time and field survey. The Orders were also sorted out by the categories of Basic Disaster Prevention Plan in Japan to figure out a framework of the Orders. Further, by using the framework, the authors have proposed a continual revision process of disaster management plan. [This abstract is not included in the PDF]

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       It is necessary to understand the characteristics of crimes by looking down at their environment for reducing crimes for children. Besides this, proper countermeasures considering target crimes and regional characteristics are sought at right way, time, place and target objectives. However, proper supporting system for implementation of good countermeasures is not developed. Then, the authors have analyzed crime environment for children by Work Breakdown Structure method and have proposed a database and a system for analysis that can support establishment and implementation of proper countermeasures. [This abstract is not included in the PDF]

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       Retrofitting of low earthquake-resistant houses is a key issue for earthquake disaster mitigation. In this research, we developed educational tool learning from structural damage photos taken after the past earthquakes. First, we reviewed lessons learnt from past earthquake damage investigations and developed website for explaining causes of housing damage and its countermeasures. About 300 house owners accessed the website and effectiveness of learning was evaluated by questionnaires just before and after the learning and seismic diagnosis. The number of house owners who wished to conduct retrofitting and seismic diagnosis increased after learning and effectiveness of learning was verified. [This abstract is not included in the PDF]

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    Sustainability is about following the triple bottom line principles of environmental preservation, social responsibility and economic profitability. Traditional cost-benefit analysis with a short-term horizon fails to capture economic benefits of a product/solution satisfying the first two principles, leading to perceived economic infeasibility of sustainable products/solutions. This review article first discusses the sustainability concept and the need for a business case for sustainability before outlining the issues and components that should be considered to make a strong business case for sustainable products/solutions. Based on presently available knowledge, an integrated, holistic, life-cycle based and longer-term approach to costs and benefits with due inclusion of intangibles is proposed to make a proper business case for such product/solutions in order to make them commercialized and absorbed in the society effectively and faster. It is also shown how elements of green building movement, such as LEED green building assessment system, are making tremendous market transformation by presenting a good business case for green buildings.

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       Intergreen time is the interval between the end of the green time for one traffic stream and the beginning of the green time for the next. The onset of green of conflict streams is delayed because of intergreen, which leads to lost time. The current lost time estimation method at signalized intersections in Japan lacks sufficient consideration of the characteristics of right-turn traffic under different phasing. Therefore, this paper first theoretically examined the differences in lost time of right-turn traffic caused by various phasing by the use of time-space diagram. Then, field data was collected to validate, and the aforementioned differences were demonstrated. [This abstract is not included in the PDF]

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       Gridlock is one of the big issues in traffic simulation. It deteriorates the road network performance as different vehicles block their courses each other. This study classified the problems in the case of a single intersection and multiple intersections. Then, a measure to avoid gridlock situation was proposed and its effect was verified. As a result, the gridlock in a single intersection which contains a loop of short links can be solved by adding virtual diagonal links. [This abstract is not included in the PDF]

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       Gross primary productivity (GPP) is total amount of carbon absorption by canopy. This indicator can help us to understand the carbon cycle process. This study proposed the method to estimate GPP by integrating remotely sensed data to the ecological modelling, focused on 3-PG model. First, the parameter in 3-PG model is done the parameterization for deciduous broadleaf forest based on in situ measurement from flux tower. Then, MODIS 10 days composite data is calculated in terms of vegetation index to compare with LAI data. Regarding on LAI-VI relationship, 3-PG model is extended to Spatial 3-PG model, then GPP is estimated. The result shows that estimated GPP has good agreement to observed GPP as well. [This abstract is not included in the PDF]

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       The purpose of this study is to analyze externality of forest creation for landscape policy. For this purpose, we use hedonic approach. We analyzed land prices in 23 wards of Tokyo using forest configuration classified by ASTER image. The results were as follows. 1) The externalities of forest were the most fit to land price when forest from land price point was within 300m. 2) The externalities of forest creation were up to 320,400 yen per one square meter and 137,061 yen per one square meter on average. 3) This method is basically useful to apply to landscape policy. [This abstract is not included in the PDF]

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       The purpose of this study is to integrate remote sensing of three-dimensional forest structure with a process-based ecosystem model for calculating how much carbon dioxide forests can absorb. Three-dimensional forest structures, such as stem biomass, tree height and tree number, are extracted by Air-borne LiDAR point clouds, ALOS/PRISM (Daichi) and time-series aerial photographs. The forest growth model “3-PG” which is on of the process-based ecosystem model is used. Each forest stand is replicated the extracted three-dimensional forest structure by tuning forest stand parameters. After tuning, the model estimate future three-dimensional forest structure. [This abstract is not included in the PDF]

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       We developed a vector based extraction methodology of an individual tree in a Japanese Cider plantation. The developed methodology can extract each tree based on tree crown shape without the need of rasterization. Moreover, in order to extract trees with various crown sizes, the methodology consisted of two modules. One was for trees with an isolated tree crown shape. The other was for trees with suppressed tree crown shape. As a result of comparison between the geographical position of extracted tree and of measured tree, the accuracy of positioning was found to be within 1m. [This abstract is not included in the PDF]

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       The satellite and aerial remote sensing technology is the high expected methods to collect geographical information widely, promptly, and periodically. This report shows the overview of our comprehensive investigation for the use of remote sensing technology in large-scale disaster assessments with various examples of recent disasters caused by earthquakes, tsunami, rainstorms, volcanic hazard and so on. [This abstract is not included in the PDF]

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       The stress-strain curves for carbide cermets which are typical sprayed coatings have been identified by using the elasto-viscoplastic damage constitutive equation with twelve material constants based on continuum damage mechanics. The three-dimensional finite element program equipped with the identified elasto-viscoplastic damage constitutive equation is applicable to the elasto-viscoplastic damage finite element analysis of structures with sprayed coating. [This abstract is not included in the PDF]

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       The concept of continuum damage mechanics for damage and fracture behaviors has been extended to the analysis of self-healing processes. The extended damage mechanics modeling has been applied to the simulation of the self-healing processes of two kinds of fatigue-damaged polymer materials, polystylene and polycarbonate, by annealing. [This abstract is not included in the PDF]

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       Jellyfish are of great scientific interest due to their unique biological make-up and the role they play in the vertical carbon cycle of our seas. However, there exist a number of technical challenges that must be overcome in order to observe and closely study them at sea. This research proposes a new method to observe and sample Jellyfish using AUVs (autonomous underwater vehicles) and introduces the testbed T-pod (Target Perception Orientation and Detainment system), designed for autonomous recognition, tracking and sampling of deep-sea Jellyfish. This paper describes the concept and design of T-pod and presents the results of a basic experiment carried out. In this experiment, the vehicle succeeded in autonomously recognizing, tracking and catching a model Jellyfish in a tank. [This abstract is not included in the PDF]

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       Vibro-acoustical numerical analysis using FDTD method (Finite-difference time-domain method) was applied to determination of sound insulation performance of wall systems. In the numerical analysis, Rayleigh damping was considered in the bending wave equation in order to make accurate calculation of the sound insulation and the modeling parameters were identified based on the measured loss factor of plasterboards. The sound insulation performance of single and double wall made of plasterboards was analyzed and the calculation results were validated by comparing to measurement results. For the determination of transmission loss of the wall systems, reverberation room method was numerically simulated. The calculation results showed good agreement with the measured ones and the validity of the calculation method was confirmed. [This abstract is not included in the PDF]

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       An emerging influenza pandemic has been observed, and devastating recurrent waves are anticipated. Although production of a pandemic vaccine has already started, an upper limit of production-capacity exists, and moreover, the seasonal influenza vaccine also has to be manufactured. The present study proposes an optimization method for resource allocation of vaccine production. If immunization coverage of the pandemic vaccine can achieve close to its own threshold, spending all resources for the pandemic vaccine is not optimal. Provided that our model sufficiently captures the realism, optimal allocation for the pandemic vaccine in the next year would be 82.2% among a total of 50 million vaccines, minimizing the expected number of deaths. If the reproduction number of the pandemic strain is greater than 0.9 times that of the seasonal strain, spending all the remaining resources in this year for the pandemic vaccine is deemed appropriate. [This abstract is not included in the PDF]

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