scholarly journals IMPACT OF GRANULES FROM CRUSHED EXPANDED POLYSTYRENE PACKAGE ON PROPERTIES OF THERMO-INSULATING PLASTER

2014 ◽  
Vol 20 (4) ◽  
pp. 581-589 ◽  
Author(s):  
Jurga Šeputytė-Jucikė ◽  
Georgij Arsenij Sezeman ◽  
Marijonas Sinica ◽  
Modestas Kligys ◽  
Saulius Vaitkus

The paper deals with the use of lightweight porous aggregate, i.e. crushed expanded polystyrene package crumbs (EPSC) in the composition of thermo-insulating plaster. Its effectiveness is compared to that of spherical granules of expanded polystyrene – white coloured (EPS) and grey coloured (NEOPOR). The content of lightweight aggregate changed from 1.25 to 1.75 l/kg of dry mix. The investigation focused on properties of modified plaster, such as density, compressive strength, thermal conductivity and water vapour permeability. It was established that EPSC reduce density of plaster from 1350 to 530 kg/m3, improving such properties as thermal conductivity and water vapour permeability but decreasing compressive strength. In addition, the paper established the adhesion force of plaster (content of lightweight aggregate was 1.25 l/kg of dry mix) to ceramics, silicate and autoclaved aerated concrete masonry elements. The character of macrostructure of plaster was considered, as well as bonding with a coat of decorative paint. It was found that plaster with EPSC has similar properties to plasters with EPS and NEOPOR aggregates; however, in case of EPSC, the relative vapour resistance is better. The provided regression equations can be used for prediction of differently modified plasters.

2021 ◽  
Vol 54 (4) ◽  
Author(s):  
P. F. G. Banfill

AbstractRetrofitting thermal insulation to solid masonry walls alters their hygrothermal behaviour, which can be modelled by hygrothermal simulation software. However, such software needs values of key material properties to ensure satisfactory results and until now data has not been available for Scottish masonry buildings. This work aims to contribute to a Scotland-specific dataset of material properties for use by designers working on such buildings. Thermal conductivity, water vapour permeability, sorptivity, water absorption coefficient, hygroscopic sorption, density and porosity were all determined experimentally for selected historic and contemporary masonry materials. Within the range of materials tested three groups of materials properties emerge. Natural hydraulic lime mortars, hot-mixed quicklime mortar and earth mortar all show comparatively low density, high porosity, low thermal conductivity, high water vapour permeability and variable but generally high hygroscopic sorption. Craigleith, Hailes and Giffnock sandstones, no longer available but obtained from conservation works on historic buildings, and Locharbriggs and Hazeldean sandstones, obtained from current production, all show intermediate values of these properties. Crathes granodiorite and Scottish whinstone (from current production) show high density, low porosity, high thermal conductivity, low water vapour permeability and low hygroscopic sorption. It is shown that these materials are all relevant to Scottish buildings constructed in traditional masonry and this paper presents the first comprehensive set of hygrothermal property data for them.


2015 ◽  
Vol 824 ◽  
pp. 95-99
Author(s):  
Jaromír Žumár ◽  
Zbyšek Pavlík ◽  
Robert Černý

An application of a transient method for investigation of water vapour permeability of autoclaved aerated concrete is presented in the paper. Relative humidity profiles along the longitudinal axis of the rod shaped sample are measured using a transient arrangement of a diffusion experiment. Using an inverse analysis of experimentally accessed relative humidity profiles, water vapour permeability of studied material is calculated as function of relative humidity. In the inverse analysis, the Boltzmann-Matano treatment is used as the most straightforward way to the solution of inverse problems to parabolic water vapour diffusion equation.


2016 ◽  
Vol 8 (1) ◽  
pp. 31-40 ◽  
Author(s):  
Jurga Šeputytė-Jucikė ◽  
Marijonas Sinica

The main objective of this study is to create a lightweight aggregate concrete (LWAC) with a low thermal conductivity coefficient using expanded glass (EG) aggregate, produced from waste glass or crushed expanded polystyrene waste, obtained by crushing waste packing tare of household appliances. Research related to the effects of the amount of Portland cement (PC) as well as EG aggregates and crushed expanded polystyrene waste on physical (density, thermal conductivity coefficient, water absorption and capillary coefficient) and mechanical (compressive strength) properties of LWAC samples are provided. Insulating LWAC based on a small amount of PC and lightweight EG aggregates and crushed expanded polystyrene waste, with especially low thermal conductivity coefficient values (from 0.070 to 0.098 W/ (m·K)) has been developed. A strong relationship between thermal conductivity coefficient and density of LWAC samples was obtained. The density of LWAC samples depending on the amount of PC ranged between 225 and 335 kg/m3. A partial replacement of EG aggregate by crushed expanded polystyrene waste, results in relative density decrease of LWAC samples. In LWAC samples the increased amount of PC results in increased compressive strength.


2016 ◽  
Vol 28 (3) ◽  
pp. 328-339 ◽  
Author(s):  
Rajesh Mishra ◽  
Arumugam Veerakumar ◽  
Jiri Militky

Purpose – The purpose of this paper is to investigate effect of material properties in 3D knitted fabrics on thermo-physiological comfort. Design/methodology/approach – In the present study six different spacer fabrics were developed. Among these six fabrics, it was classified into two groups for convenient analysis of results, the first group has been developed using polyester/polypropylene blend with three different proportion and second group with polyester/polypropylene/lycra blend having another three different composition. As a spacer yarn, three different types of 88 dtex polyester monofilament yarn and polyester multifilament yarns (167 dtex and 14.5 tex) were used and 14.5 tex polypropylene and 44 dtex lycra multifilament yarns were also used for the face and back side of the spacer fabrics (Table I). These fabrics were developed in Syntax Pvt Ltd Czech Republic. Findings – The main influence on the water vapour permeability of warp knitted spacer fabrics is the kind of raw material, i.e. fibre wetting and wicking. Also there is no correlation between air permeability and water vapour permeability. It is found that both air permeability and thermal conductivity are closely related to the fabric density. It is also found that the fabric characteristics of spacer fabric show a very significant effect on the air permeability, thermal conductivity and mechanical properties of spacer fabric. Therefore, selection of spacer fabric for winter clothing according to its fabric characteristics. Practical implications – The main objective of the present study is to produce spacer knitted 3D fabrics suitable for defined climatic conditions to be used as clothing or in sports goods. Originality/value – New 3D knitted spacer fabrics can be produced with improved comfort properties.


2018 ◽  
Vol 42 (6) ◽  
pp. 771-787 ◽  
Author(s):  
Barbora Krejcirikova ◽  
Carsten Rode ◽  
Ruut Peuhkuri

Two sewage sludge ashes were used as substitutes for cement and their effect on the hygrothermal properties of mortar was examined. Different cement to ash ratios and two ash pre-treatment methods (water washing and grinding) were in focus. The impact of cement replacement by sewage sludge ashes on thermal conductivity, sorption isotherms, water vapour permeability and carbonation was described with standard cement-based mortar as the reference material. Measurement results showed that thermal conductivity decreased by 15% when 30% of the cement was replaced by sewage sludge ash. Water vapour permeability increased as the cement to ash ratio was reduced. Sorption was tested by two methods; although differences in the sorption isotherms of mortars were reported when a climatic chamber method was applied, no differences, or only minor differences, were observed with the desiccator method. Measurements revealed that cement-based mortar possessed a higher content of carbonate than cement-ash-based mortar, and it thus appears that the carbonation rate was higher when the cement content was high.


2019 ◽  
Vol 27 (5(137)) ◽  
pp. 80-89
Author(s):  
Elena Tomovska ◽  
Lubos Hes

In this paper, the thermophysiological characteristics of low weight knitted polyamide and polyamide/elastane fabrics for pantyhose differing in terms of filament count were studied. Alambeta and Permetest devices were used to measure the thermal conductivity, thermal resistance, thermal absorptivity, evaporative resistance and relative water vapour permeability. The results indicated that fabrics made of finer filaments have lower thermal conductivity, thermal resistance, thermal absorptivity and evaporative resistance values.


2021 ◽  
Vol 2069 (1) ◽  
pp. 012004
Author(s):  
A Ruus ◽  
T Koosapoeg ◽  
M Pau ◽  
T Kalamees ◽  
M Põldaru

Abstract Hemp concrete is considered to be a carbon negative material. Hemp absorbs CO2 during the growth and lime needs CO2 for carbonation. The material, which has good thermal insulation properties, is used as a non-bearing wall material or plaster. For such use the hygrothermal properties of a material must be well known especially when indoor insulation is in focus. In the current study hemp concrete produced in two different ways was in focus and following the hygrothermal properties of hemp concrete as a building material were studied: water absorption (EN 1015-18), water vapour sorption (EN 12571), water vapour permeability (EN 12572) and thermal conductivity (EN 12667). The results of the study can be used in hygrotheramal calculations and modelling.


Data in Brief ◽  
2018 ◽  
Vol 18 ◽  
pp. 1057-1063 ◽  
Author(s):  
Luciano Di Maio ◽  
Bartolomeo Coppola ◽  
Luc Courard ◽  
Frédéric Michel ◽  
Loredana Incarnato ◽  
...  

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