Performances and properties of steel and composite prestressed tendons - A review.

The primary drawback of concrete lies in its low tensile strength, prompting the development of various solutions to enhance this aspect. A notable approach is the utilization of Prestressed Reinforced Concrete (PRC) with tendons, aimed at bolstering its tensile strength. As the use of diverse tendon types in the PRC continues to surge, a review becomes imperative to delve into this evolution.

Chlorophyll Fluorescence Imaging for Environmental Stress Diagnosis in Crops.

The field of plant phenotype is used to analyze the shape and physiological characteristics of crops in multiple dimensions. Imaging, using non-destructive optical characteristics of plants, analyzes growth characteristics through spectral data. Among these, fluorescence imaging technology is a method of evaluating the physiological characteristics of crops by inducing plant excitation using a specific light source.

Fire retardant performance, toxicity and combustion characteristics, and numerical evaluation of core materials for sandwich panels.

According to fire accident statistics, fires in buildings are increasing. The flame-retardant performance of insulation materials is considered an important factor for preventing the spread of fire and ensuring evacuation. This study evaluated the flame-retardant performance and combustion characteristics of four types of organic thermal insulation used as core materials in sandwich panels.

Verification of particle matter generation due to deterioration of building materials as the cause of indoor fine dust.

Particles of fine dust are pollutants that adversely affect indoor air quality and exacerbate human respiratory diseases. The aging of the building was pointed out as a source of fine dust indoors. The aging of buildings has various causes of deterioration.

Passive PM control plan of educational buildings by using airtight improvement technologies in South Korea.

Modern people spend most of their time indoors. Therefore, controlling indoor air quality is one of the most important factors for health. The indoor fine dust concentration is affected by the outdoor fine dust concentration.

Effect of eco-friendly pervious concrete with amorphous metallic fiber on evaporative cooling performance.

Impervious pavements exist in large proportions in most cities owing to the high-impact development of the transportation infrastructure. However, this type of pavement causes environmental issues such as waterlogging, floods, and urban heat islands. Pervious concrete (PC), which is a novel pavement material characterized by a porous structure that allows water to percolate through it, is an important solution to these issues.

Hazard evaluation of indoor environment based on long-term pollutant emission characteristics of building insulation materials: An empirical study.

Insulation materials are essential components in construction, and their main objective is to increase the efficiency of thermal energy by minimizing internal and external thermal exchange. Accordingly, research and development studies are being actively conducted to increase the thermal resistance of insulation materials, and high-performance insulation materials that use organic chemicals have been developed after industrialization. However, thermal insulation comprising chemicals poses a potential risk of pollutant emissions and can cause health problems.

Evaluation of thermal properties and acetaldehyde adsorption performance of sustainable composites using waste wood and biochar.

In order to vitalize the use of wood, which is a sustainable resource, increase the utilization of resources through the recycling of wood waste, and reduce environmental pollution in the waste disposal process, biocomposite was manufactured by using biochar which can be produced with wood waste and is effective in carbon isolation. The thermal characteristics and acetaldehyde adsorption performance of the prepared biocomposite were evaluated based on the pore characteristics, surface functional groups, crystal structure, and elemental analysis results of the biochar. As a result of the experiment, as the content of biochar increased, the thermal conductivity of the biocomposite decreased and the specific heat was not affected.

A comparative analysis of biochar, activated carbon, expanded graphite, and multi-walled carbon nanotubes with respect to PCM loading and energy-storage capacities.

To obtain high thermal performance composite phase change materials (PCMs), various other supporting materials have been utilized to encapsulate organic PCMs. In this study, four carbon materials (biochar, activated carbon, carbon nanotubes, and expanded graphite) were introduced to support heptadecane. The composite PCMs were designed using vacuum impregnation techniques.

Evaluation of hygrothermal performance of wood-derived biocomposite with biochar in response to climate change.

Wood is a sustainable resource and building material. It provides an excellent response to climate change and has excellent insulation performance. However, structural defects may occur due to decay from moisture, resulting in poor dimensional stability.

Numerical analysis on the hygrothermal behavior of building envelope according to CLT wall assembly considering the hygrothermal-environmental zone in Korea.

As buildings generally have become larger and more airtight, the ventilation rate has decreased further, causing insufficient ventilation which leads to moisture problems such as condensation, mold growth, reduction of thermal insulation performance and corrosion of building materials. In order to prevent moisture problems, it is essential to understand the thermal and hygric status of a climatic region. In this study, the hygrothermal environmental zone considering not only the thermal environment but also the hygric environment was derived by analyzing the climate environment in Korea.

Evaluation of environmental impact on the formaldehyde emission and flame-retardant performance of thermal insulation materials.

Thermal insulation material, an essential building material, is used to preserve heat or block heat gains in buildings. Insulation material is currently attracting significant attention, and thermal conductivity, i.e.

Microstructure and thermal characterization of aerogel-graphite polyurethane spray-foam composite for high efficiency thermal energy utilization.

Aerogel is a superinsulating material with an extremely low thermal conductivity (<0.015 W/m·K), high porosity (>99 %), and extremely low density. In this study, a new closed-cell spray polyurethane (PU) foam with aerogel was developed and investigated.

Evaluation and analysis of volatile organic compounds and formaldehyde emission of building products in accordance with legal standards: A statistical experimental study.

Building materials have been developed mainly for thermal performance, strength, low energy consumption, and aesthetics. Consequently, large amounts of chemicals have been added to building products, resulting in the release of abundant pollutants that adversely affect human health. In particular, pollutants from the materials used to build modern dwellings can cause sick house syndrome, which leads to health resilience problems and diseases.

Field study on the improvement of indoor air quality with toluene adsorption finishing materials in an urban residential apartment.

To improve the indoor air quality of apartments in Korea, a toluene adsorptive paint was manufactured and tested for its efficiency to remove the indoor toluene released from wallpaper adhesives. The toluene adsorptive paint was prepared by blending activated carbon and inorganic binder, and the pore characteristics and chemical functional groups of the activated carbon were analyzed to determine whether the micropores and surface functionalities of activated carbon affected toluene adsorption. Toluene adsorption performance of the toluene adsorptive paint was confirmed through static and verification experiments.

Characterization of biocomposite using coconut oil impregnated biochar as latent heat storage insulation.

Objective of this research was to characterize properties of the latent heat storage biocomposite (LHSBC) as a novel material that can be employed as a latent heat storage insulation by using biochar. Biochars produced from waste material pine cone, pine saw dust, and paper mill sludge were vacuum impregnated with a bio-based phase change material (PCM), coconut oil, to prepare LHSBCs. In particular, this paper analyzed the chemical stability, latent heat storage performance, thermal conductivity, and thermal stability of LHSBCs based on results of fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), laser flash method and thermogravimetric analysis (TGA).

Assessment of recycled ceramic-based inorganic insulation for improving energy efficiency and flame retardancy of buildings.

In addition to the mitigation of carbon emissions through the reduction of building energy consumption, the prevention of fire spread in buildings is important an important task globally. Therefore, a growing interest towards building materials that can simultaneously contribute to energy savings and provide good flame-retardant performance in buildings exist. The flame-retardant performances of buildings can be improved through the use of inorganic building materials during construction.

Spent coffee grounds as supporting materials to produce bio-composite PCM with natural waxes.

Novel kinds of bio composite Phase change materials were prepared by the use of bio-wastes. Of the by-products, coffee wastes, which is currently consumed and abandoned as coffee as a drink, was used as the supporting material for PCM. It was found through chemical composition of FTIR of SCBW, SCPW, SCGW and that the coffee wastes were effectively vacuum impregnated into each natural wax.

Biochar-red clay composites for energy efficiency as eco-friendly building materials: Thermal and mechanical performance.

Biochar and red clay were used to develop eco-friendly building materials with improved thermal and mechanical performance. Rice husk, coconut shell, and bamboo were prepared by thermally decomposing as biochar. Thermal conductivity measurements, scanning electron microscopy imaging, compressive strength measurements, and an infrared heat transfer experiment were performed, and the results showed that the mixture of biochar tends to lower the thermal conductivity.

Evaluation of Toluene Adsorption Performance of Mortar Adhesives Using Porous Carbon Material as Adsorbent.

Porous carbon materials are advantageous in adsorbing pollutants due to their wide range of specific surface areas, pore diameter, and pore volume. Among the porous carbon materials in the current study, expanded graphite, xGnP, xGnP C-300, xGnP C-500, and xGnP C-750 were prepared as adsorbent materials. Brunauer-Emmett-Teller (BET) analysis was conducted to select the adsorbent material through the analysis of the specific surface area, pore size, and pore volume of the prepared porous carbon materials.

Evaluation of the Adsorption Performance and Sustainability of Exfoliated Graphite Nanoplatelets (xGnP) for VOCs.

Exfoliated graphite nanoplatelets (xGnP), which combine the layered structure and low price of nanoclays with the superior mechanical, electrical, and thermal properties of carbon nanotubes, are very cost-effective, and can simultaneously provide a multitude of physical and chemical property enhancements. In this study, we evaluated xGnP's adsorption performance of volatile organic compounds (VOCs) according to thermal extractor (TE) analysis for seven days in order to use the xGnP as an adsorption material of pollutants. In addition, we carried out a sustainability evaluation in order to evaluate its adsorption capacity over 28 days.