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Based on heating tests and load-bearing fire tests, this paper aims to discuss the charring rate, the temperature distribution in the section and the load-bearing capacity of structural glued laminated timber beams not only during the heating phase during a 1-h standard fire in accordance with ISO 834-1 but also during the cooling phase.

Heating tests were carried out to confirm the charring rate and the temperature distribution in the cross-section of the beams. Loading tests under fire conditions were carried out to obtain the load-deformation behavior (i.e. the stiffness, maximum load and ductility) of the beam.

The temperature at the centroid reached approximately 30°C after 1 h and then increased gradually until reaching 110-200°C after 4 h, during the cooling phase. The maximum load of the specimen exposed to a 1-h standard fire was reduced to approximately 30 per cent of that of the specimen at ambient temperature. The maximum load of the specimen exposed to a 1-h standard fire and 3 h of natural cooling in the furnace was reduced to approximately 14 per cent. In case of taking into consideration of the strength reduction at elevated temperature, the reduction ratio of the calculated bending resistance agreed with that of the test results during not only heating phase but also cooling phase.

The results of this study state that it is possible to study on strength reduction in cooling phase for end of heating, timber structural which has not been clarified. It is believed that it is possible to appropriately evaluate the fire performance, including the cooling phase of the timber structural.

This paper aims to discuss the fire performance of glulam timber beams based on their deflection behavior and load-bearing period, which were obtained from load-bearing fire tests under constant load conditions.

In this report, the fire performance, primarily deflection behavior and load-bearing period of glued laminated (glulam) timber beams will be discussed from the standpoint of load-bearing fire tests conducted during the cooling phase under constant load conditions. Then, based on the charring depth and the per section temperature transformation obtained from loading test results, the load-bearing capacity of the glulam timber beams will be discussed using the effective section method and the strength reduction factor, which will be calculated in accordance with the European standards for the design of timber structures (Eurocode 5).

In the cooling phase, the charring rate is decreases. However, as the temperature in the cross section rises, the deflection is increases. The failure mode was bending failure because of tensile failure of the lamina at the bottom of the beam. Moreover, a gap caused by shear failure in a growth ring in the beam cross-section in the vicinity of the centroid axis was observed. Shear failure was observed up until 1 to 3 h before end of heating. The calculated shear strength far exceeded the test results. Shear strength for elevated temperature of glued laminated timber is likely to decrease than the shear strength in Eurocode 5.

Unlike other elements, a characteristic problem of timber elements is that their load-bearing capacity decreases as they are consumed in a fire, and their bearing capacities may continue to degrade even after the fuel in the room has been exhausted. Therefore, the structural fire performance of timber elements should be clarified during not only the heating phase but also the subsequent cooling phase. However, there are few reports on the load-bearing capacity of timber elements that take the cooling phase after a fire into consideration.

This paper aims to investigate the fire performance of composite beams when considering the hogging moment resistance of the fin-plate beam-to-girder joints including the effect of continuity of reinforcements.

Experiments on composite beams with fin-plate joints protected only at the beam ends are conducted. The test parameter is the specification of reinforcement, which affects the rotational restraint of the beam ends. In addition, a simple method for predicting the failure time of the beam using an evaluation model based on the bending moment resistance of the beam considering the hogging moment resistance of the fin-plate joint and the reinforcement is also presented.

The test results indicate that the failure time of the beam is extended by the hogging moment resistance of the joints. This is particularly noticeable when using a reinforcing bar with a large plastic deformation capability. The predicted failure times based on the evaluation method corresponded well with the test results.

Recent studies have proposed large deformation analysis methods using FEM that can be used for fire-resistant design of beams including joints, but these cannot always be applicable in practice due to the cost and its complexity. Our method can consider the hogging moment resistance of the joint and the temperature distribution in the axial direction using a simple method without requirement of FEM.

The purpose of this study is to clarify both tensile and shear strength for self-drilling screws, which are manufactured from high-strength, martensitic-stainless and austenitic stainless-steel bars, and the load-bearing capacity of single overlapped screwed connections using steel sheets and self-drilling screws at elevated temperatures.

Tensile/shear loading tests for the self-drilling screw were conducted to obtain basic information on the tensile and shear strengths at elevated temperatures and examine the relationships between both. Shear loading tests for the screwed connections at elevated temperatures were conducted to examine the shear strength and transition of failure modes depending on the test temperature.

The tensile and shear strengths as well as the reduction factors at the elevated temperature for each steel grade of the self-drilling screw were quantified. Furthermore, either screw shear or sheet bearing failure mode depending on the test temperature was observed for the screwed connection.

The transition of the failure modes for the screwed connection could be explained using the calculation formulae for the shear strengths at elevated temperatures, which were proposed in this study.

As forestry contributes to the reduction of greenhouse gases by CO₂ fixation, in recent years, use of wood in buildings has attracted all over the world more attention. However, construction of large wood structures is almost inexistent within urban areas in Japan. This is due to the Japanese law on fire protection of wood buildings in cities, which is considered very strict with severe requirements. This paper aims to present a research work relative to the development of one-hour fire-resistant wood structural elements for buildings in cities. The developed elements are composed of three layers made of laminated timber.

These wood structural elements, made of glued laminated timber with self-charring-stop, have sufficient fire resistance during and after a fire and comply with the strict Japanese standard for wood structural elements, which stipulates that such elements have to withstand the whole dead-load of concerned buildings after fire. To comply with such requirements, new elements of glued laminated timber with self-charring-stop layer were developed, and their performance was confirmed. Several fire-resistant tests conducted on columns, beams, column-beam joints, connections between beams and walls and beams with holes were carried out.

All tests proved that the elements have sufficient fire resistance. No damage was found out at the load-bearing part of the elements after testing. As the developed elements have two layers protecting the load-bearing part, the temperature in the load-bearing part could be retained below 260°C (carbonization temperature) and provide the elements with a sufficient fire resistance for 1 h.

These wood structural elements have already been applied in six projects, where large-size wooden buildings were constructed in urban areas in Japan.

The proposed structural elements use a novel technique. Every wooden element is composed of three layers made of glued laminated timber. The elements have a typical performance of self-charring-stop after fire without need for water of firefighters. More technologies related to these elements, including column-beam joints and beams with holes and effect of crack, were also developed to design and construct safe wooden buildings.

In this paper, we present a proposed information environment (PROPIE) for enhanced interaction and value‐adding of electronic documents (e‐documents). The design of PROPIE was based on a thorough user needs and requirements assessment in interacting with information through well‐documented findings, and a focus group with twelve participants to elicit features that were deemed desirable in future interactions. The design was also based on an earlier work which reviewed the advancements in various user interface (UI) technologies, visualisation and interactive techniques, and a consideration of novel information structuring and organisation techniques that pose important implications for the design of more advanced UIs. Providing a suite of novel features and interactive tools that can be flexibly combined, PROPIE allows users to apply multiple novel ways to query intuitively and navigate information in an e‐document. The querying and browsing processes in PROPIE are supported by various interactive and visualisation techniques. Users work within a visually sovereign, integrated environment for information gathering and organising, based on navigable, fractional information objects that are also affiliated with rich metadata and additional layers of value‐adding information. A set of interface mock‐ups was developed to demonstrate the potential of the environment in supporting the design of a new generation of electronic journals (e‐journals). We report here empirical results from a study conducted to obtain representative users‘ feedback with regard to using PROPIE for interacting with e‐journals. Twenty‐two participants from a variety of academic backgrounds participated in the evaluation. Overall, PROPIE was found to have the potential both for enhancing the user’s interaction with information captured within e‐journals and for adding value to e‐documents in various ways.

Our research aim is to propose a support model for problem‐solving oriented learning (PSOL) and implement a humancentric system that supports learners and thereby develops their ability. We propose a human‐centric interactive framework for PSOL by employing the research results in the educational psychology field. The characteristic of our research is that our system understands the principle knowledge to support users through human‐computer interactions. It is very important to clarify the principle knowledge of the target application domain and develop the system based on it. We call the principle knowledge as ontology. By embedding ontology into the basis of a system, we can implement a more positive navigation function. In this paper, we analyze the learners’ cognitive activities in PSOL, propose a support model that encourages self‐regulated planning processes, and illustrate an interactive environment for making effective problem‐solving and learning processes based on the ontology.

The purpose of this study is to investigate the influencing factors on the charring behaviour of timber, the char layer and the charring depth in non-standard fires.

This paper summarizes outcomes of tests, investigating the influences on the charring behavior of timber by varying the oxygen content and the gas velocity in the compartment. Results show that charring is depending on the fire compartment temperature, but results show further that at higher oxygen flow, char contraction was observed affecting the protective function of the char layer.

In particular, in the cooling phase, char contraction should be considered which may have a significant impact on performance-based design using non-standard temperature fire curves where the complete fire history including the cooling phase has to be taken into account.

Up to now, some research on non-standard fire exposed timber member has been performed, mainly based on standard fire resistance tests where boundary conditions as gas flow and oxygen content especially in the decay phase are not measured or documented. The approach presented in this paper is the first documented fire tests with timber documenting the data required.

This study aims to investigate whether epistemological assessment is a suitable approach to evaluate students’ learning of dietary knowledge via the use of an augmented reality (AR) information system. Students’ perceived dietary knowledge was compared before and after learning with the AR system. Two major questions were addressed: Did students improve their understanding of dietary knowledge after the use of AR information system? Did students gain more appropriate understanding of dietary knowledge after the use of AR information system?

A mixed-methods approach was used in the study. The mobile AR system was used among 65 volunteered non-nutrition-major college students recruited in campus. For promoting epistemological development of personal dietary knowledge, students practiced with life experiences to access daily dietary information. Pre- and post-tests of students’ understanding of dietary knowledge were compared. Interviews with 20 students were used for gathering in-depth research data to analyse students’ epistemological understanding of dietary knowledge.

The epistemological assessment indicated an improvement in learning after the use of the AR system. Students gradually gained awareness of dietary knowledge and changed their perceptions of their dietary behaviours. Epistemological approaches to the analysis of students’ conceptual change in dietary knowledge revealed a significant increase in the mean nutritional concepts (p < 0.01) and a decrease in their mean misconceptions (p < 0.001) after learning via the mobile nutrition monitoring system. Learning assessment of 65 students also indicated a significant increase from the post-test after learning with the system (p < 0.0001).

This study might have its limitations, as it only assessed learning using a pretest-posttest design for a specific learning context over a short period of learning time. The use of interviews based on the epistemological approach might have its limitations in the interpretations of the phenomenon. Future implementations can also be extended to different populations to promote self-monitoring dietary behaviours.

The findings of this study will contribute to the application of AR in learning about dietary knowledge. The research involving in-depth observation of students’ learning relevant to personal nutritional information needs via mobile AR might provide potential contributions to dietitian professionals and health education.

The recent unprecedented growth of information in digital form advocates the need for better ways to interact with this vast amount of richly‐conveyed information. This paper reviews and analyses the design considerations of an advanced information environment for users to interact in novel manners with online documents such as electronic journals. The interaction environment is also intended to support value‐adding of electronic documents. The design is inspired by analyses of user requirements in interacting with information, by advances in the electronic information world, and by innovations in human‐computer interaction. These led to the derivation and proposal of a set of properties in both the interaction environment and the information objects within the environment. The environment is a visually‐rich, interactive information environment based on user‐controlled malleability and integration with various interaction tools. The information objects within the environment are fractionally structured, contextualized and explicable, queriable and navigable at multiple levels of granularity, and associated with layers of additional information and metadata.