Phase-Change Materials in Concrete: Opportunities and Challenges for Sustainable Construction and Building Materials

The use of phase-change materials (PCM) in concrete has revealed promising results in terms of clean energy storage. However, the negative impact of the interaction between PCM and concrete on the mechanical and durability properties limits field applications, leading to a shift of the research to incorporate PCM into concrete using different techniques to overcome these issues. The storage of clean energy via PCM significantly supports the UN SDG 7 target of affordable and clean energy. Therefore, the present study focuses on three aspects: PCM type, the effect of PCM on concrete properties, and connecting the outcome of PCM concrete composite to the United Nations sustainable development goals (UN SDGs). The compensation of reduction in strength of PCM-contained concrete is possible up to some extent with the use of nanomaterials and supplementary cementitious materials. As PCM-incorporated concrete is categorized a type of building material, the large-scale use of this material will affect the different stages associated with building lifetimes. Therefore, in the present study, the possible amendments of the different associated stages of building lifetimes after the use of PCM-incorporated concrete are discussed and mapped in consideration of the UN SDGs 7, 11, and 12. The current challenges in the widespread use of PCM are lower thermal conductivity, the trade-off between concrete strength and PCM, and absence of the link between the outcome of PCM-concrete composite and UN SDGs. The global prospects of PCM-incorporated concrete as part of the effort to attain the UN SDGs as studied here will motivate architects, designers, practicing engineers, and researchers to accelerate their efforts to promote the consideration of PCM-containing concrete ultimately to attain net zero carbon emissions from building infrastructure for a sustainable future.

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Review of Solutions for the Use of Phase Change Materials in Geopolymers

Materials ◽

10.3390/ma14206044 ◽

2021 ◽

Vol 14 (20) ◽

pp. 6044

Author(s):

Michał Łach ◽

Kinga Pławecka ◽

Agnieszka Bąk ◽

Marcin Adamczyk ◽

Patrycja Bazan ◽

...

Keyword(s):

Phase Change ◽

Building Materials ◽

Phase Change Materials ◽

Matrix Material ◽

Cost Effective ◽

Mass Scale ◽

Sustainable Construction ◽

Thermal Gradients ◽

Effective Form ◽

The Matrix

The paper deals with the possibility of using Phase Change Materials (PCM) in concretes and geopolymer composites. The article presents the most important properties of PCM materials, their types, and their characteristics. A review of the latest research results related to their use in geopolymer materials is presented. The benefits of using PCM in building materials include the improvement of thermal comfort inside the building, and also the fact that the additive in the form of PCM reduces thermal gradients and unifies the temperature inside the concrete mix, which can reduce the risk of cracking. The paper also presents a critical analysis related to the feasibility of mass scale implementations of such composites. It was found that the use of PCM in sustainable construction is necessary and inevitable, and will bring a number of benefits, but it still requires large financial resources and time for more comprehensive research. Despite the fact that PCM materials have been known for many years, it is necessary to refine their form to very stable phases that can be used in general construction as well as to develop them in a cost-effective form. The selection of these materials should also be based on the knowledge of the matrix material.

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THE EFFECT OF MICROENCAPSULATED PHASE-CHANGE MATERIAL ON THE COMPRESSIVE STRENGTH OF STRUCTURAL CONCRETE

Journal of Green Building ◽

10.3992/jgb.8.3.116 ◽

2013 ◽

Vol 8 (3) ◽

pp. 116-124 ◽

Cited By ~ 22

Author(s):

Chad Norvell ◽

David J. Sailor ◽

Peter Dusicka

Keyword(s):

Compressive Strength ◽

Energy Storage ◽

Phase Change ◽

Building Materials ◽

Energy Use ◽

Phase Change Materials ◽

Structural Integrity ◽

Concrete Strength ◽

Hardened Concrete ◽

Filler Materials

Latent heat energy storage through phase-change materials (PCMs) is one possible strategy to control interior temperatures in buildings, improve thermal comfort, and passively reduce building energy use associated with heating and cooling. While PCMs integrated into building structure elements have been studied since the 1970s, challenges of integrating PCMs into building materials while maintaining their heat storage benefits have limited their application in practice. The recent introduction of microencapsulated phase-change materials provides the energy storage capability of PCMs in micron-scale, chemically-inert capsules that can be easily integrated into composite materials such as gypsum wallboard and concrete. The size and physical properties of microencapsulated PCMs suggest that they will behave similarly to filler materials in concrete. Such filler materials are generally less than 125 μm in diameter and can increase concrete strength when added to a mix. This study uses the compressive strength of hardened concrete mixes with varying amounts of PCM to evaluate the effect of PCM addition on concrete structural integrity.

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Green Concrete for a Circular Economy: A Review on Sustainability, Durability, and Structural Properties

Materials ◽

10.3390/ma14020351 ◽

2021 ◽

Vol 14 (2) ◽

pp. 351

Author(s):

Abathar Al-Hamrani ◽

Murat Kucukvar ◽

Wael Alnahhal ◽

Elsadig Mahdi ◽

Nuri C. Onat

Keyword(s):

Large Scale ◽

Concrete Strength ◽

American Concrete Institute ◽

Cementitious Materials ◽

Analytical Investigation ◽

Supplementary Cementitious Materials ◽

Primary Concern ◽

Portland Cement Concrete ◽

Green Concrete ◽

Coarse Aggregates

A primary concern of conventional Portland cement concrete (PCC) is associated with the massive amount of global cement and natural coarse aggregates (NCA) consumption, which causes depletion of natural resources on the one hand and ecological problems on the other. As a result, the concept of green concrete (GC), by replacing cement with supplementary cementitious materials (SCMs) such as ground granulated blast furnace slag (GGBFS), fly ash (FA), silica fume (SF), and metakaolin (MK), or replacing NCA with recycled coarse aggregates, can play an essential role in addressing the environmental threat of PCC. Currently, there is a growing body of literature that emphasizes the importance of implementing GC in concrete applications. Therefore, this paper has conducted a systematic literature review through the peer-reviewed literature database Scopus. A total of 114 papers were reviewed that cover the following areas: (1) sustainability benefits of GC, (2) mechanical behavior of GC in terms of compressive strength, (3) durability properties of GC under several environmental exposures, (4) structural performance of GC in large-scale reinforced beams under shear and flexure, and (5) analytical investigation that compares the GC shear capacities of previously tested beams with major design codes and proposed models. Based on this review, the reader will be able to select the optimum replacement level of cement with one of the SCMs to achieve a certain concrete strength range that would suit a certain concrete application. Also, the analysis of durability performance revealed that the addition of SCMs is not recommended in concrete exposed to a higher temperature than 400 °C. Moreover, combining GGBFS with FA in a concrete mix was noticed to be superior to PCC in terms of long-term resistance to sulfate attack. The single most striking observation to emerge from the data comparison of the experimentally tested beams with the available concrete shear design equations is that the beams having up to 70% of FA as a replacement to OPC or up to 100% of RCA as a replacement to NCA were conservatively predicted by the equations of Japan Society of Civil Engineers (JSCE-1997), the American Concrete Institute (ACI 318-19), and the Canadian Standards Association (CSA-A23.3-14).

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Rheological Behaviour of Cementitious Materials Incorporating Solid–Solid Phase Change Materials

Materials ◽

10.3390/ma15010020 ◽

2021 ◽

Vol 15 (1) ◽

pp. 20

Author(s):

Lionel Plancher ◽

Alexandre Pierre ◽

Giao T. M. Nguyen ◽

Ronan L. Hébert ◽

Béatrice A. Ledésert ◽

...

Keyword(s):

Yield Strength ◽

Phase Change ◽

Building Materials ◽

Phase Change Materials ◽

Solid Phase ◽

Construction Materials ◽

Rheological Behaviour ◽

Cementitious Materials ◽

Major Step ◽

High Latent Heat

Nowadays, thermal regulation of the indoor environment is mandatory to reduce greenhouse gas emissions. The incorporation of Phase Change Materials (PCMs) and especially solid–solid PCMs (s/s PCMs) into building materials can be a major step forward in reducing energy consumption. Such materials are used for their high latent heat to save and release heat during phase change. To integrate these products in the fabrication of cementitious materials, it is essential to predict their influence on the rheological behaviour of construction materials. In this work, rheological measurements were carried out on composite suspensions made of cement or mortar plus s/s PCMs. Results showed that the fitting of the Herschel–Bulkley model with a constant value of flow exponent was reliable. The s/s PCMs influenced the consistency and the yield strength values, with the yield strength value being only slightly affected. The adaptation of an existing viscosity model is proposed to predict the consistency value of suspensions. Finally, an innovative approach to predict the flow behaviour is proposed and we highlight the research needs to mainstream the use of s/s PCMs in construction materials.

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A Rapid Method for Low Temperature Microencapsulation of Phase Change Materials (PCMs) Using a Coiled Tube Ultraviolet Reactor

Energies ◽

10.3390/en14237867 ◽

2021 ◽

Vol 14 (23) ◽

pp. 7867

Author(s):

Jawaad A. Ansari ◽

Refat Al-Shannaq ◽

Jamal Kurdi ◽

Shaheen A. Al-Muhtaseb ◽

Charles A. Ikutegbe ◽

...

Keyword(s):

Phase Change ◽

Large Scale ◽

Building Materials ◽

Phase Change Materials ◽

Average Particle Size ◽

Thermal Mass ◽

Average Particle ◽

Ambient Conditions ◽

Coiled Tube ◽

Uv Reactor

Microencapsulation of phase change materials (PCMs) remain a suitable option within building materials, as they contribute to the thermal mass and provide an energy buffer, an added benefit. This paper presents a novel method for the rapid fabrication of microencapsulated phase change materials (PCMs) at ambient conditions in a perfluoroalkoxy (PFA) coiled tube ultraviolet (UV) reactor. The objective of this study was to optimize key parameters such as the product yield and quality of the as-prepared microcapsules. Rubitherm® RT-21™ PCM was microencapsulated within shells of poly-methyl-methacrylate (PMMA) through a suspension emulsion polymerization approach, where the crosslinking of polymers was driven by UV radiations with an appropriate photoinitiator. The characteristics of the resulting PCM microcapsules were found to be affected by the volumetric flow rate of the emulsion inside the coiled tube reactor. Higher volumetric flow rates led to higher PCM contents and higher microencapsulation efficiency, resulting in an average particle size of 6.5 µm. Furthermore, the effect of curing time on the PCM microcapsule properties was investigated. The optimum encapsulation yield, conversion, efficiency and PCM content were observed after 10 min of polymerization time. The thermal analysis indicated that the developed process had an efficiency of 85.8%, and the capsules were characterized with excellent thermal properties. Compared to the conventional thermal microencapsulation processes, the use of a coiled tube UV reactor with an appropriate photoinitiator enables the encapsulation of heat-sensitive PCMs at ambient conditions, and reduces the microencapsulation time dramatically. As a result, this novel microencapsulation approach can lead to a wider scope of PCM encapsulation and enable rapid, continuous and potentially large-scale industrial production of PCM microcapsules with low energy consumption.

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Effect of ground granulated blast funrnace slag and fly ash on strength, permeability, and under-water abrasion of fine-grained concrete

Transport and Communication Science Journal ◽

10.25073/tcsj.71.7.4 ◽

2020 ◽

Vol 71 (7) ◽

pp. 775-788

Author(s):

Quyet Truong Van ◽

Sang Nguyen Thanh

Keyword(s):

Fly Ash ◽

Concrete Strength ◽

Cementitious Materials ◽

Supplementary Cementitious Materials ◽

Chloride Permeability ◽

Cement Replacement ◽

Fine Grained ◽

Granulated Blast Furnace Slag ◽

Compressive Strength Test ◽

Economic Ground

The utilisation of supplementary cementitious materials (SCMs) is widespread in the concrete industry because of the performance benefits and economic. Ground granulated blast furnace slag (GGBFS) and fly ash (FA) have been used as the SCMs in concrete for reducing the weight of cement and improving durability properties. In this study, GGBFS at different cement replacement ratios of 0%, 20%, 40% and 60% by weight were used in fine-grained concrete. The ternary binders containing GGBFS and FA at cement replacement ratio of 60% by weight have also evaluated. Flexural and compressive strength test, rapid chloride permeability test and under-water abrasion test were performed. Experimental results show that the increase in concrete strength with GGBFS contents from 20% to 40% but at a higher period of maturity (56 days and more). The chloride permeability the under-water abrasion reduced with the increasing cement replacement by GGBFS or a combination of GGBFS and FA

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Testing a Gypsum Composite Based on Raw Gypsum with a Direct Admixture of Paraffin and Polymer to Improve Thermal Properties

Materials ◽

10.3390/ma14123241 ◽

2021 ◽

Vol 14 (12) ◽

pp. 3241

Author(s):

Krzysztof Powała ◽

Andrzej Obraniak ◽

Dariusz Heim

Keyword(s):

Thermal Conductivity ◽

Heat Capacity ◽

Thermal Properties ◽

Phase Change ◽

Large Scale ◽

Building Materials ◽

Residential Buildings ◽

Energy Performance ◽

Polymer Content ◽

Volumetric Heat Capacity

The implemented new legal regulations regarding thermal comfort, the energy performance of residential buildings, and proecological requirements require the design of new building materials, the use of which will improve the thermal efficiency of newly built and renovated buildings. Therefore, many companies producing building materials strive to improve the properties of their products by reducing the weight of the materials, increasing their mechanical properties, and improving their insulating properties. Currently, there are solutions in phase-change materials (PCM) production technology, such as microencapsulation, but its application on a large scale is extremely costly. This paper presents a solution to the abovementioned problem through the creation and testing of a composite, i.e., a new mixture of gypsum, paraffin, and polymer, which can be used in the production of plasterboard. The presented solution uses a material (PCM) which improves the thermal properties of the composite by taking advantage of the phase-change phenomenon. The study analyzes the influence of polymer content in the total mass of a composite in relation to its thermal conductivity, volumetric heat capacity, and diffusivity. Based on the results contained in this article, the best solution appears to be a mixture with 0.1% polymer content. It is definitely visible in the tests which use drying, hardening time, and paraffin absorption. It differs slightly from the best result in the thermal conductivity test, while it is comparable in terms of volumetric heat capacity and differs slightly from the best result in the thermal diffusivity test.

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Special Issue: Supplementary Cementitious Materials in Concrete, Part I

Materials ◽

10.3390/ma14092291 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2291

Author(s):

Alessandro P. Fantilli ◽

Daria Jóźwiak-Niedźwiedzka

Keyword(s):

Environmental Impact ◽

Portland Cement ◽

Building Materials ◽

Cementitious Materials ◽

Supplementary Cementitious Materials ◽

Special Issue ◽

Cement Production ◽

Concrete Part

The environmental impact of the Portland cement production and the large use of cement-based building materials is a growing problem [...]

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Programmable phase-change metasurfaces on waveguides for multimode photonic convolutional neural network

Nature Communications ◽

10.1038/s41467-020-20365-z ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Changming Wu ◽

Heshan Yu ◽

Seokhyeong Lee ◽

Ruoming Peng ◽

Ichiro Takeuchi ◽

...

Keyword(s):

Neural Network ◽

Neural Networks ◽

Phase Change ◽

Convolutional Neural Network ◽

Large Scale ◽

Phase Change Materials ◽

Refractive Index Change ◽

Optical Computing ◽

Machine Learning Algorithms ◽

Matrix Vector Multiplication

AbstractNeuromorphic photonics has recently emerged as a promising hardware accelerator, with significant potential speed and energy advantages over digital electronics for machine learning algorithms, such as neural networks of various types. Integrated photonic networks are particularly powerful in performing analog computing of matrix-vector multiplication (MVM) as they afford unparalleled speed and bandwidth density for data transmission. Incorporating nonvolatile phase-change materials in integrated photonic devices enables indispensable programming and in-memory computing capabilities for on-chip optical computing. Here, we demonstrate a multimode photonic computing core consisting of an array of programable mode converters based on on-waveguide metasurfaces made of phase-change materials. The programmable converters utilize the refractive index change of the phase-change material Ge2Sb2Te5 during phase transition to control the waveguide spatial modes with a very high precision of up to 64 levels in modal contrast. This contrast is used to represent the matrix elements, with 6-bit resolution and both positive and negative values, to perform MVM computation in neural network algorithms. We demonstrate a prototypical optical convolutional neural network that can perform image processing and recognition tasks with high accuracy. With a broad operation bandwidth and a compact device footprint, the demonstrated multimode photonic core is promising toward large-scale photonic neural networks with ultrahigh computation throughputs.

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