The application of broken expanded polystyrene particles in thermal insulation coating material

Development of low thermal conductivity and high strength building materials is an emerging strategy to solve the heavy energy consumption of buildings. This study develops sustainable alkali activated materials (AAMs) for structural members from waste expanded polystyrene (EPS) beads and reduced graphene oxide (rGO) to simultaneously meet the thermal insulation and mechanical requirements of building energy conservation. It was found that the thermal conductivity of AAMs with 80 vol.% EPS and 0.04 wt.% rGO (E8–G4) decreased by 74% compared to the AAMs without EPS and rGO (E0). The 28-day compressive and flexural strengths of E8–G4 increased by 29.8% and 26.5% with the addition of 80 vol.% EPS and 0.04 wt.% rGO, compared to the sample with 80 vol.% EPS without rGO (E8). In terms of compressive strength, thermal conductivity, and cost, the efficiency index of E8–G4 was higher than those of other materials. A building model made from AAMs was designed using building information modeling (BIM) tools to simulate energy consumption, and 31.78% of total energy consumption (including heating and cooling) was saved in the building operation period in Harbin City, China. Hence, AAMs made of waste EPS beads and rGO can realize the structural and functional integrated application in the future.

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Experimental research on employed expanded polystyrene (EPS) for lightened sulfate heave of subgrade by thermal insulation properties

Geotextiles and Geomembranes ◽

10.1016/j.geotexmem.2020.02.009 ◽

2020 ◽

Vol 48 (4) ◽

pp. 516-523 ◽

Cited By ~ 2

Author(s):

Shuquan Peng ◽

Fan Wang ◽

Xibing Li ◽

Ling Fan

Keyword(s):

Thermal Insulation ◽

Experimental Research ◽

Expanded Polystyrene

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Inverted roof insulation kits and their durability

MATEC Web of Conferences ◽

10.1051/matecconf/201816308005 ◽

2018 ◽

Vol 163 ◽

pp. 08005 ◽

Cited By ~ 1

Author(s):

Barbara Francke ◽

Robert Geryło

Keyword(s):

Water Absorption ◽

Thermal Insulation ◽

Laboratory Tests ◽

Expanded Polystyrene ◽

Insulation Layer ◽

Performance Properties ◽

Climate Conditions ◽

Freeze Thaw ◽

Moisture Increase

In the paper there was analyzed a mechanism of loss of performance properties of inverted roof insulation kits resulted by moisture increase of the insulation layers. This problem is very important in such systems because the thermal insulation is placed above the waterproofing layer and is not protected against water absorption. Abovementioned problem is more and more common in the course of building’s utilization in Polish climate conditions. Because inverted roof kits are based on extruded polystyrene (XPS) and expanded polystyrene (EPS), those materials have been used in tested samples. The results of laboratory tests showed the phenomenon and its effect on durability and sustainability of roof covering performance. It was also found that the biggest influence on the increase of moisture in the thermal insulation layer has not the long term water absorption by immersion but freeze –thaw cycles.

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Genetic Algorithm Applied to Multi-Criteria Selection of Thermal Insulation on Industrial Shed Roof

Buildings ◽

10.3390/buildings9120238 ◽

2019 ◽

Vol 9 (12) ◽

pp. 238 ◽

Cited By ~ 1

Author(s):

Stamoulis ◽

Santos ◽

Lenz ◽

Tusset

Keyword(s):

Genetic Algorithm ◽

Thermal Comfort ◽

Thermal Insulation ◽

Optimization Technique ◽

Building Envelope ◽

Expanded Polystyrene ◽

Insulation Material ◽

Clothing Insulation ◽

Climate Conditions ◽

Selection Of

The rational use of energy has motivated research on improving the energy efficiency of buildings, which are responsible for a large share of world consumption. A strategy to achieve this goal is the application of optimized thermal insulation on a building envelope to avoid thermal exchanges with the external environment, reducing the use of heating, ventilation and air-conditioning (HVAC) systems. In order to contribute to the best choice of insulation applied to an industrial shed roof, this study aims to provide an optimization tool to assist this process. Beyond the thermal comfort and cost of the insulation, some hygrothermic properties also have been analysed to obtain the best insulation option. To implement this optimization technique, several thermo-energetic simulations of an industrial shed were performed using the Domus software, applying 4 types of insulation material (polyurethane, expanded polystyrene, rockwool and glass wool) on the roof. Ten thicknesses ranging from 0.5 cm to 5 cm were considered, with the purpose of obtaining different thermal comfort indexes (PPD, predicted percentage dissatisfied). Posteriorly, the best insulation ranking has been obtained from the weights assigned to the parameters in the objective function, using the technique of the genetic algorithm (GA) applied to multi-criteria selection. The optimization results showed that polyurethane (PU) insulation, applied with a thickness of 1 cm was the best option for the roof, considering the building functional parameters, occupant metabolic activity, clothing insulation and climate conditions. On the other hand, when the Brazilian standard was utilized, rock wool (2 cm) was considered the best choice.

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Change in Conductive–Radiative Heat Transfer Mechanism Forced by Graphite Microfiller in Expanded Polystyrene Thermal Insulation—Experimental and Simulated Investigations

Materials ◽

10.3390/ma13112626 ◽

2020 ◽

Vol 13 (11) ◽

pp. 2626

Author(s):

Aurelia Blazejczyk ◽

Cezariusz Jastrzebski ◽

Michał Wierzbicki

Keyword(s):

Heat Transfer ◽

Thermal Conductivity ◽

Thermal Resistance ◽

Thermal Insulation ◽

Radiative Heat Transfer ◽

Radiative Heat ◽

Expanded Polystyrene ◽

Transfer Mechanism ◽

Total Thermal Conductivity ◽

Heat Transfer Mechanism

This article introduces an innovative approach to the investigation of the conductive–radiative heat transfer mechanism in expanded polystyrene (EPS) thermal insulation at negligible convection. Closed-cell EPS foam (bulk density 14–17 kg·m−3) in the form of panels (of thickness 0.02–0.18 m) was tested with 1–15 µm graphite microparticles (GMP) at two different industrial concentrations (up to 4.3% of the EPS mass). A heat flow meter (HFM) was found to be precise enough to observe all thermal effects under study: the dependence of the total thermal conductivity on thickness, density, and GMP content, as well as the thermal resistance relative gain. An alternative explanation of the total thermal conductivity “thickness effect” is proposed. The conductive–radiative components of the total thermal conductivity were separated, by comparing measured (with and without Al-foil) and simulated (i.e., calculated based on data reported in the literature) results. This helps to elucidate why a small addition of GMP (below 4.3%) forces such an evident drop in total thermal conductivity, down to 0.03 W·m−1·K−1. As proposed, a physical cause is related to the change in mechanism of the heat transfer by conduction and radiation. The main accomplishment is discovering that the change forced by GMP in the polymer matrix thermal conduction may dominate the radiation change. Hence, the matrix conduction component change is considered to be the major cause of the observed drop in total thermal conductivity of EPS insulation. At the microscopic level of the molecules or chains (e.g., in polymers), significant differences observed in the intensity of Raman spectra and in the glass transition temperature increase on differential scanning calorimetry(DSC) thermograms, when comparing EPS foam with and without GMP, complementarily support the above statement. An additional practical achievement is finding the maximum thickness at which one may reduce the “grey” EPS insulating layer, with respect to “dotted” EPS at a required level of thermal resistance. In the case of the thickest (0.30 m) panels for a passive building, above 18% of thickness reduction is found to be possible.

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