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Abstract

The paper presents analytical and numerical analysis of the pin connection resistance made of high-strength steel used in the temporary bridge ŽM 60. The assessment of the pin connection was performed according to standard [1] and also using numerical analysis by means of numerical sophisticated calculations based on FEM analyses.

Abstract

The article presents test research on thermal sensations, thermal preferences, as well as general thermal sensations in a single-family building. Graphs were drawn to determine the frequency of answers chosen by the respondents and the relationship between temperature and thermal sensations, as well as the influence of relative humidity on thermal sensations. A comparison was also made between the average thermal sensation vote and the PMV index, which determines the ‘predicted mean vote’ - estimated by the Fanger model. The aim of the study was to compare the actual feelings of the respondents with standard guidelines. As a result of this analysis it was found that the thermal sensations of the respondents do not comply with the adopted model included in the standard.

Abstract

The first precast post-tensioned bridges in Slovakia are approaching 60 years of their service life. Facing an aging infrastructure, it is necessary to assess their present structural condition and residual life expectancy. Different types and methods of anchorage system were developed and available for first post-tensioned bridges around the world. The reliability and functionality of anchorages contribute to the proper behaviour of post-tensioning system. The considerable effect of aggressive environment (frost, chloride salts, humidity) and environmental load (CO2) leads to corrosion of anchorages and prestressing steel with the risk of a sudden unexpected damage to bridge. The research work deals into finding more details of this structural part. During the demolition of damaged post-tensioned bridges built in 1960s several anchorages were removed and analysed. The material properties, size parameters and performed tensile tests of a wedge anchorage system are summarised in this paper. The findings from this study can be used as input parameters for numerical simulation and durability assessment of similar aged existing post-tensioned bridges.

Abstract

An increase production of wastes from different companies and agricultural areas creates severe surrounding trouble in terms of management and removal in Ethiopia. Utilization of by-products and residue in construction work is an excellent alternative solution in reducing disposal problems. In this research, the application of sawdust ash in asphalt concrete production is investigated as filler material. Physical and chemical tests were investigated for Saw Dust Ash (SDA). Asphalt specimen prepared using basaltic stone dust without sawdust as filler used as a control material. The SDA was partially replaced with 3 %, 6 %, 9 %, and 12 % by amount of basaltic dust. Performance evaluation of combinations was explored with fatigue, tensile strength, and deformation resistances experiment. The outcome pointed that the use of SDA as packing material enhanced the fatigue life and permanent deformation of asphalt concrete with variable temperature. Furthermore, it was identified that the combination with SDA indicated less sensitive to moisture than basaltic dust. Research finding indicated, an optimum value of SDA could be replaced the basaltic dust is 12 % in asphaltic concrete production.

Abstract

This paper presents the calculations of the summer thermal stability of a critical room of the given building. In this case, the critical room of the building is an attic room. Using two different software (SIMULACE and DesignBuilder), the summer thermal stability of the attic room was evaluated according to the Czech standard ČSN 73 0540-2 [1]. This standard compares the calculated and required value of the maximum internal temperature in the summer period. The results from both software were compared with the Czech standard and also with each other. The resulting temperature courses in the interior differ by a few Celsius degrees. In conclusion, the causes of different results are discussed as well as the advantages and disadvantages of both software.

Abstract

The port of Bushehr, with its valuable and unique historical texture, completely matches with its unbearable climate conditions. Over hundreds of years, the port has provided an appropriate ground for human life as no air conditioner is needed there. Unfortunately, this valuable old texture has been destroyed inadvertently. New buildings in the port are just superficial copies of the old buildings’ external surfaces, with no attention to their goal, i.e., the provision of thermal comfort for inhabitants. The new buildings are dramatically increasing without considering the historical texture and climate. As a result, the inhabitants have to use air conditioners in most months continuously; hence, there would be an increase in energy consumption and a disruption in climate balance. This study has been conducted to compare the compatibility of such architecture with the climate and its success in providing climate comfort for the inhabitants. According to the information obtained from the study, the old houses built more than 100 years ago using traditional design had better performance in adaptability with climate. Accordingly, the exploitation of traditional instructions and patterns in a new format would largely reduce energy consumption in hot seasons and eliminate the need for heating in cold seasons. In this regard, a huge amount of energy is saved, resulting in less damage to the environment.

Abstract

Iranians used wind catchers to achieve harmony between a structure and the environment and guarantee the environmental comfort of the indoor areas. Wind catchers were the symbols of Persian architecture and with introduction of modern technologies, these traditional elements became obsolete. Rapid population and traffic lead to use underground spaces in cities. This paper proves the ability of wind-catchers to provide natural ventilation in underground spaces based on climatic parameters. Simulation was conducted in complete computational fluid dynamics package to simulate wind in underground space. Results demonstrate that in specific climate condition, wind-catchers could provide natural ventilation for underground space.

Abstract

This research aims at comparing the thermal performance of walls made from traditional and alternative building materials. The experimental study involves five types of walls were studied based on perforated ceramic bricks and a mixture of clay, sand with various straw proportions. Specialized software and the finite element method (FEA) were employed for modelling of the thermal processes and their visualization for the different types of walls. A simulation modelling algorithm was developed. The models developed show very good convergence of the results and provide for subsequent design and thermal calculation of constructions made by environmentally friendly materials.

Abstract

A summary of the diffusion and development of time-geography in East Asia, specifically in Japan and China, is presented in this article. Previous studies have provided reviews of time-geographic research and spacetime behaviour research in both countries. Few studies, however, have told the story about how and why timegeography diffused into East Asia. By showing and analysing the academic life paths of Yoshio Arai and Yanwei Chai, we conclude that the development of time-geography in Japan and China goes hand in hand with their academic progress. Moreover, the interactions within their academic life paths mark some key events that promoted time-geography significantly. The similarities and differences between their academic life paths are also analysed in this article. Both scholars shared some common research topics, such as childcare problems, urban spatial structures and socioeconomic transformations, which were also the most prominent characteristics of time-geography in East Asia. In addition, the socioeconomic backgrounds of their academic life paths are also quite similar, which reflects the close relationship between time-geography and societal needs. Finally, this article discusses the effectiveness and disadvantages of the academic life path method, as the method has proven to be an important tool in analysing the role that key scholars play in promoting a certain discipline. In conclusion, the diffusion and development of time-geography in East Asia can hardly have happened without both individual scholars’ hard work and the exchange and cooperation activities between scholars.