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Interest in utilizing industrial waste and by-products in construction materials is growing, given recent concerns about sustainable practices aligning with the principles of the circular economy. Within this context, compressed earth blocks (CEBs) are emerging as an alternative to traditional building materials, offering cost-effectiveness, energy efficiency, and reduced environmental impact. This systematic review comprehensively explores the incorporation of industrial waste and by-products, including construction and demolition waste (CDW), in the production of CEBs. An approach based on the PRISMA model is adopted to analyze the outcomes from primary scientific databases, namely Scopus and Web of Science. The advantages and limitations of incorporating industrial waste and by-products into CEBs are thoroughly discussed. The results show that these waste materials can improve the mechanical, durability, and thermal insulation properties of CEBs. However, careful selection and processing are necessary for compatibility with CEB production. Factors like particle size distribution, chemical composition, and processing techniques significantly influence block performance. This research highlights the potential for more sustainable practices in CEB production while enhancing the mechanical and functional properties of this building product. The findings contribute to advancing knowledge in the field, benefiting researchers, practitioners, and policymakers interested in sustainable construction practices. • Incorporating industrial waste/by-products into compressed earth block is reviewed. • Mechanical, thermal and durability properties of waste-based CEBs are analyzed. • Industrial waste and by-products can improve the functional performance of CEBs. • Research gaps include compatibility issues and manufacturing standardization. • In-depth studies on environmental impact assessment are encouraged. [ABSTRACT FROM AUTHOR]

Studying the effects of elevated temperatures on nanoconcrete is a complex issue due to multiple factors and conditions that affect it. A comprehensive study is necessary to determine the real behavior of nanomodified concrete at high temperatures using different nano-modifiers for various nanomaterials, including those derived from waste. This study investigated the effect of elevated temperatures (200 °C, 400 °C, 600 °C and 800 °C) on concrete containing nano-silica, nano-aluminum, and nano-glass materials as a partial replacement for cement at percentages of 1, 2, and 3 % by weight. Compressive strength test and XRD, TGA and SEM were performed to determine residual Compressive strength, chemical composition, mass loss, and microstructure, respectively. The results showed that incorporating nanomaterials into concrete boosted its residual compressive strength at elevated temperatures. Optimal percentages of nano glass and nano-silica were 1 % at room temperature and 200 °C, and 3 % at 400 °C and 600 °C, respectively. For 800 °C, 2 % nano aluminum was most effective. The findings conform with dense microstructure, particularly in ITZ because of the filling effects and higher CSH with a reduction in calcium hydroxide that was observed by XRD, as well as the correlation with lower mass loss of nano concrete. • Nano modified concrete showed optimal performance before and after exposure to elevated temperatures. • Using 3 % nano-silica, 2 % nano-aluminum, and 1 % nano-glass at elevated temperatures greatly improves the behavior of concrete. • Improvement in microstructure and weight loss were observed through TGA and SEM and analyzed by XRD when using nanomaterials. • using of nano-sized recycled glass in concrete showed good results at different temperatures. [ABSTRACT FROM AUTHOR]

There has been a noticeable global trend in the usage of natural, ecologically conscious fibers as reinforcements in the production of inexpensive, lighter polymer composites. Specifically, the basalt natural fibers are the most intriguing due to their characteristics among the various types of natural fibers (i.e., plants, animals, or minerals) that could be utilized as reinforcement. In the composites sector, basalt fibers (BF) have garnered a lot of interest due to their exceptional mechanical and thermal capabilities, as well as their chemical stability. In comparison to carbon, glass, or other mineral fibers generally, the environmental effect of the entire complex of technical processes involved in generating and using basalt fibers is significantly lower. Within this framework, this suggested review seeks to investigate and analyze the behavior of basalt mineral materials in the forms of fiber, powder, and mats when it is reinforced with different polymer matrices. Additionally, this study discusses the basic methods of producing basalt fibers, their characteristics, composition, and the impact of surface treatment on the fibers. Further sections address the developments in 3D printing and its possible applications in a variety of industries, encompassing mechanical, thermal, tribology, and water absorption/wettability studies. It has been noted that for both structural and non-structural applications, basalt fibers are the most advantageous substitutes and prospective reinforcements in place of glass fibers. While the quantity of BF has a significant impact on mechanical durability and basalt-fiber reinforced composites' (BFRCs) performance over time, another important factor that affects how well BFRCs perform is fiber-matrix interaction. To enhance this fiber-matrix interaction, a variety of chemical treatments (acidic, basic, and plasma) on the basalt fiber are being reported by several studies. The primary drawback of this chemical treatment is that the basalt fiber is harmed by high acid or alkali concentrations. During the long-term chemical treatment, the corrosive layer thickness significantly increased, mostly due to the presence of SiO 2. The extant research clearly indicates that augmenting the volume fraction of basalt fibers improved the composite's capacity to endure impact and absorb energy. In many experiments, basalt fibers have demonstrated greater resistance to moisture conditions when compared to natural fibers derived from plants. Since the basalt is an extremely durable and rigid material, it may be used to make frictional materials to minimize wear and friction. However, increased mass manufacturing of basalt fibers will be necessary to fulfill demand before they can be widely used as reinforcing element for structural composites. This might also make basalt fibers more affordable than more conventional reinforcements like glass and carbon fibers. [Display omitted] • Basalt fibers as a sustainable and ecologically benign reinforcing element. • Basalt fibers might be used in place of naturally obtaining crops or plant fibers. • Basalt fibers improved the composite's shock resistance and energy absorption. • Electro-technical applications can benefit from basalt fibers. • Basalt fibers are useful for the transportation and storage of radioactive objects. [ABSTRACT FROM AUTHOR]

In this study, we successfully applied an external magnetic field for the first time in preparing oriented steel fiber reinforced mullite castable (OSFRMC). The impact of the castable's rheology, duration of exposure to the magnetic field and strength of the magnetic field on the orientation of steel fibers and the properties of the refractory castable was investigated. When the duration of exposure to the magnetic field was set at 60 seconds and the strength of the magnetic field was 2.5 mT, an orientation index of steel fibers in the refractory castable of 0.96 was achieved. This specific castable contained 6 wt% of microsilica. Moreover, the castable with a high orientation index (0.96) of steel fibers exhibited significant improvement in mechanical strength and thermal shock resistance compared to the untreated castable. In order to investigate the fracture behavior of steel fiber-reinforced refractory castables with different fiber orientations, a comparative study was conducted using force-displacement curves and digital image correlation techniques. The primary factor behind this improvement is the directional alignment of steel fibers, which enhances the bridging effect and crack deflection toughness within the material. • Optimization of castables' rheology was a key step to prepare the castables. • The orientation of steel fiber had a great influence on the properties of castables. • Magnetic field was applied to prepare the castable with oriented steel fibers. [ABSTRACT FROM AUTHOR]

High-strength thermal insulation mortar, with its excellent mechanical properties and thermal insulation performance, is commonly used in building structure insulation and reinforcement renovations. In this study, vitrified microbeads and expanded perlite (EP) were used as thermal insulation materials to create high-strength thermal insulation mortar. The effects of the replacement percentage of these materials (50%, 65%, 75%, and 80%) on the density, water absorption, porosity, compressive and flexural strength, and thermal conductivity of the mortar were studied. The results show that increased replacement percentages of vitrified microbead (EP) led to a decrease in the density of the mortar and an increase in the water absorption rate and porosity. Furthermore, when the replacement percentages were increased, the compressive and flexural strength and the thermal conductivity of the mortar were reduced. Comparative analysis of the pore structure of high-strength thermal insulation mortar using scanning electron microscopy and digital microscope revealed the influence of vitrified microbead (EP) on the internal pore structure of high-strength thermal insulation mortar. The influence coefficient (η s) of volume replacement percentage of insulation materials was introduced using the Hamilton and Crosser models. Furthermore, the prediction model of thermal conductivity of high-strength thermal insulation mortar was established under different volume replacement percentages of vitrified microbead (EP). The calculated values of the model matched well with the measured values, with the ratios of the calculated values of the model to the experimental ones ranging from 0.85 to 1.15. • The physical, mechanical, and thermal conductive properties of mortar are found to be influenced by the amount of insulation. • The prediction model of thermal conductivity of high-strength thermal insulation mortar is established. [ABSTRACT FROM AUTHOR]

Seashells accumulate rapidly, particularly in coastal areas and in countries that consume a lot of seafood. In order to be recycled and used in ordinary building materials, we have carried out a study into the feasibility of using the seashells in plaster as a substitute and additive. Two cases of incorporation were carried out, the first involving the substitution of plaster by seashell powder in percentages (4%, 8%, 12%, 16% and 20% by mass), the second consisting of the use of the powder as an additive in percentages (2%, 4%, 6%, 8% and 10%). The compressive and flexural strength values are close to those of the control gypsum. However, the use of powder as a substitute can improve the thermal insulation and durability of the gypsum composite. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sandwich panel with face sheet of CSB and core with PU and PU replaced with CH were studied. • PU replaced with CH at 10, 20, 30, 40 and 50 %, and material characterizations, mechanical, durability and acoustic property, thermal conductivity test were conducted. • Incorporation of CH at 10 and 20% with PU shows enhancement in various properties. • Regression analysis was conducted to validated by the suitable R2 threshold accuracy as R2 > 0.90. As the need for a sustainable solution increase, waste materials are gaining popularity in building applications to reduce the environmental impact. This study aims to utilize the waste Coconut Husk (CH) and Calcium Silicate Board (CSB) in a sandwich panel where Polyurethane Foam (PU) is used as a binding material which consists of A (isocyanate) and B (polyol) with a mixing ratio of A: B at 1:1.2. CH is obtained as a residue from the production of coconut shells aggregate. The PU has been replaced with CH at 10, 20, 30, 40 and 50 %, to identify the optimum replacement level. Sandwich panels of dimension 30 × 30 cm with a core thickness of 2 and 3 cm was prepared and tested to categorize their mechanical properties, thermal properties, durability properties, characterization study and sound absorption coefficient. The results show that the PU replaced with 20 % of CH has higher compression and flexural properties, owing as an optimum percentage. The inclusion of CH in the PU reduces the cell size and yields a significant improvement in acoustic behavior up to a frequency of 1600 Hz. The regression model was analyzed with the experimental data and validated by the suitable R2 threshold accuracy as R2 > 0.90. [ABSTRACT FROM AUTHOR]

• Post-curing may occur with high temperature immersion. • Resin strength tends to increase and then decrease. • The DIC clearly reflects the strain during the stretching of the resin. • DTA shows that the thermal properties of the resin are also unaffected. • DMA indicates that secondary fronts occur at high temperatures. Fibre-reinforced polymer (FRP) tendons have excellent mechanical properties and corrosion resistance and are widely used in concrete structures; however, corrosion deterioration of FRP tendons is a serious problem in a highly alkaline concrete environment owing to the hygrothermal ageing effect of the resin. Accordingly, this study investigated the macro and micro properties evolution of epoxy resin in a simulated concrete pore solution at different temperatures. The results showed that the resin properties deteriorated significantly under long-term hygrothermal immersion. However, short-term high-temperature soaking caused some of the resin to undergo post-curing, improving its properties. [ABSTRACT FROM AUTHOR]

• Lightweight concrete containing scrap-tyre-rubber-based aggregate. • A wide set of structural, mechanical, thermal and hygric properties. • Improved thermal performance, approved thermal stability up to 300 °C. • Unaffected water transport parameters, while water vapour transition increased. • Non-bearing lightweight material having benefits to the environment and economy. Increasing amount of waste tyres represents a global problem as tyres can pose a risk to the environment if not treated properly. Recycling of waste tyre rubbers in civil engineering as aggregate in cement concrete can be an effective environmental and economic approach. As problems associated with the use of waste tyre rubber in concrete production are not completely understood, a detailed analysis of rubber concrete prepared from used tyre rubber-based aggregate involving testing of its mechanical, basic physical, microstructural, hygric and thermal properties, and behaviour after exposure to elevated temperatures is presented in this paper. Testing of mechanical performance included measurement of compressive strength, flexural strength, secant and dynamic modulus of elasticity. Thermal conductivity was determined in the dependence on moisture content, from the dry to fully water saturated state. Dry volumetric heat capacity was also tested. Specific attention was paid to the hygric performance of rubberized concrete that was characterised by the water and water vapour transport parameters. Investigation of concrete properties after its thermal exposure included testing of mass loss, mechanical resistance, bulk density, and thermal conductivity that was tested as property having direct relation to concrete structural parameters. The use of scrap-tyre-rubber aggregate resulted in a decrease of the unit weight, worsening in mechanical parameters and a significant reduction in thermal conductivity of prepared rubberized concrete. Rubber-based aggregate almost did not affect water transport properties, while water vapour transport properties increased with rubber amount in the mix. No significant changes on concrete characteristics related to rubber incorporation occurred at temperatures up to 300 °C. However, after exposure to 400 °C, significant changes in measured concrete properties were observed, which was in line with the thermogravimetric analysis of the used tyre-based rubber. Nevertheless, based on rubberized concrete functional properties at common ambient conditions it can be considered as an alternative lightweight material, bringing benefits to the environment and economy as it is produced from crap available in a large amount and at a negligible cost. [ABSTRACT FROM AUTHOR]

This study evaluated the technical viability and performance of two different production processes of 3-layer sugarcane-bamboo-based particleboard (3LP) (3LP-PL: pressing in each layer; and 3LP-NPL: non-pressing in each layer) throughout their thermal, physical, mechanical and microstructural properties. The thermal conductivity was determined according to the methodology established by ASTM-E1530: 2011. Physical and mechanical properties were evaluated following the ABNT NBR 14810:2013 Brazilian Standards recommendations. Microstructural properties of the 3LP studied was assessed by using the Micro-CT technique. Thermal conductivity values of both 3LP were lower than the value required by Brazilian Standards for wood-based particleboards. Physical results indicated that the non-pressing in each layer during the 3LP production resulted in less thickness swelling (TS) and water absorption (WA). Modulus of rupture (MOR) and modulus of elasticity (MOE) of the 3LP-NPL showed an increase of 38 and 29% compared to the 3LP-PL respectively. Additionally, an increase of 31% was found for the internal bond (IB) value of the 3LP-NPL compared to the 3LP-PL. Considering the results achieved for the 3-layer sugarcane-bamboo-based particleboard the non-pressing in each layer during production presented lower TS and WA values and higher MOR, MOE and IB values. [ABSTRACT FROM AUTHOR]

• Geopolymer composites represent great potential as eco-friendly alternatives to traditional construction materials. • Precursors nature and curing conditions are key factors to improve the mechanical characteristics of geopolymer composites. • Natural fibers can significantly improve the flexural strength and toughness of geopolymer composites. • Mechanical properties of fiber-reinforced geopolymer are substantially controlled by fibers size, amount, and orientation. The construction sector is a significant contributor to global greenhouse gas emissions, resource depletion, and environmental degradation. Therefore, sustainable development in the construction sector is essential to reduce its environmental impact. Geopolymer materials have attracted particular attention offering technical properties similar to those of Portland cementitious materials with a much lower CO 2 emission and lower environmental impact. Their use as clean insulating materials seems promising due to their excellent thermal and mechanical properties. Moreover, natural fibers, such as bamboo, flax, hemp, and jute, can be used as reinforcement within the geopolymer matrix, providing additional benefits such as improved tensile and flexural strength, reduced density, and improved thermal and acoustic insulation properties. Hence, this review paper aims to explore the raw materials and manufacturing conditions involved in the formation of compact and porous geopolymer materials. In addition, the various factors affecting the properties of geopolymer materials are critically discussed and compared with those of Portland cementitious materials. Moreover, the impact of many variables, including fiber size, fiber orientation, and fiber content on the performance of natural fiber-reinforced geopolymer composites are highlighted, providing insights for future research developments. [ABSTRACT FROM AUTHOR]

Three different types of plastic waste replacing up to 50% of natural aggregates are used in concrete mix design. A wide set of basic physical, mechanical, thermal, and hygric properties of developed concretes is determined and their assessment is made using a comparison with reference data. The mechanical parameters, though decreasing with the increasing amount of plastic aggregates, are found satisfactory for non-bearing concrete structures. The up to seven times lower thermal conductivity, as compared with the reference material, provides an evidence of greatly improved thermal insulating capabilities. The hygric properties of designed concretes are characterized by an increase of water and water vapor transport parameters and a decrease of water vapor adsorption capacity with the increasing amount of plastic aggregates. Based on the obtained experimental results, a conclusion can be made that the designed lightweight concretes containing plastic waste aggregates present a prospective solution from the points of view of both plastic waste disposal and improvement of buildings' energy efficiency. [ABSTRACT FROM AUTHOR]

In this study, the influence of different alkaline activators (Na + and K + ) on the mechanical, thermal, and microstructural behaviors of metakaolin-based geopolymer mortars was investigated. Four types of mortars were manufactured, and the only difference between them was the alkaline-activating solution. Potassium and alkaline sodium silicates and potassium and sodium hydroxides were used in combination as the alkaline-activating solutions. Compressive strengths, indirect tensile strengths, and longitudinal moduli of elasticity of the mortars were evaluated along with thermal property analysis (thermogravimetric analysis and differential thermal analysis) and scanning electron microscopy (SEM). All the mortars exhibited similar compressive strength, >80 MPa, at 28 days. It was possible to observe a high gain in the mechanical strength in the early ages, which is characteristic of geopolymers. The increase in mechanical strength ranged approximately from 72% to 81% after 3 days and from 86% to 93% after 7 days with respect to the strength at 28 days. Mortars produced with alkaline sodium silicate exhibited a heterogeneous microstructure with a large number of pores, while those containing potassium silicate were denser and exhibited low porosity. Such different morphologies of the mortars are a result of the type of the alkaline cations used; their effect could also be perceived in the thermal performance of the mortars, with better performance induced by potassium silicate and potassium hydroxide. [ABSTRACT FROM AUTHOR]

The research evaluated the properties of cold-mixed epoxy asphalt (EA) and cold-mixed epoxy styrene–butadiene–styrene (SBS)-modified asphalt (ESA) for paving steel-deck bridges. Compared with ESA, EA showed longer pot life and better processability at ambient temperature, as revealed by curing rheology analysis. The cured EA showed higher glass-transition temperature, superior thermal stability, tensile strength and elongation at breaking than ESA. These may be as a result of: (i) the high thermal stability of asphalt, (ii) the formation of a cross-linking network in the cured material, and (iii) the good compatibility between the epoxy resin and the asphalt. [ABSTRACT FROM AUTHOR]

Over the past three decades, growing interest in the properties of thermal envelopes and their enhancement has led to the development of new sustainable materials. Nevertheless, Concrete Masonry Units (CMUs) with negligible thermal properties are still widely manufactured in unsustainable processes for use in the thermal envelopes of buildings. Hence, this research aims to reuse certain by-products for the development of CMUs with better thermal properties. In addition to the reference concrete, one set of blocks was manufactured with 5% sawdust in substitution of fine aggregate and another set of blocks with the same level of fine aggregate replacement together with 15% lime mud in substitution of cement. The physical, mechanical, and thermal performance of the CMUs evaluated in this paper showed that the addition of sawdust in the CMUs improved their thermal properties. On the other hand, the addition of lime mud partially counteracted the decrease in strength caused by the incorporation of the sawdust. [ABSTRACT FROM AUTHOR]

The industrial and academic world is becoming more interested in advanced composite materials owing to the increasing global awareness on environmental and social issues. From this point of view, novel epoxy hybrid composites were prepared by utilizing bean pod as an agricultural waste and calcined kaolin with the addition of varying ratios (0.5–5.0 wt%) to fixed weight of 3 wt% bean pod. The resulting hybrid composites were characterized by different analyses and tests to evaluate physico-mechanical and thermal properties. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses showed uniform dispersion of hybrid filler in the neat epoxy resin which revealed better compatibility between hybrid filler and epoxy resin. Tensile strength of hybrid composite including 2 wt% calcined kaolin (39.8 MPa) was higher than those of the other hybrid composites. The water sorption percentage of the hybrid composites was effectively decreased until 0.87% with increasing amount of calcined kaolin. The hybrid composite including 5 wt% calcined kaolin exhibited highly corrosion resistance to alkali and salty solutions compared to acidic reagents. Thermogravimetric analyses (TGA) and vicat softening temperature (VST) tests revealed that an important improvement was not observed in degradation temperatures of the hybrid composites; however, residue at 650 °C increased up to 21.0% in the presence of calcined kaolin. It can be said that the hybrid composites mentioned above came into prominence with high tensile strength, quite low water uptake and excellent corrosion resistance in alkali and salty environments. [ABSTRACT FROM AUTHOR]

Lightweight concrete and cementitious composites are increasingly studied by researchers due to their advantageous performance in reducing structural load and building’s operational energy consumption. In this research, a comprehensive and thorough study was carried out to investigate the effects of different lightweight fillers on both the mechanical and thermal properties of lightweight cementitious composites, or LWCCs. Four different types of lightweight fillers (LWFs) including expanded polystyrene (EPS) beads, dry-expanded thermoplastic microspheres (ETM), hollow glass microspheres (HGM), and fly ash cenospheres (FACs) are studied in conjunction with various particle sizes, shell wall thickness, and proportions. Both mechanical and thermophysical properties were tested for these LWCCs after 28-day curing. The results indicated that the thermal property of LWCC is mostly governed by the volume fraction of LWFs and it can be accurately predicted by the Felske equation, whereas the mechanical properties are heavily affected by the type and property of LWF particles included. It was revealed that most fly ash cenospheres (FAC) and hollow glass microspheres (HGM) with higher density are suitable for producing LWCC materials that may be used for structural applications, whereas lower density HGMs and LWFs with soft polymer shell are more suitable for nonstructural thermal insulating components. [ABSTRACT FROM AUTHOR]

This paper investigates residual thermal and mechanical properties of high-performance fiber-reinforced cementitious composites (HPFRCCs) proportioned with high-volume fly ash after exposure to 200, 400, 600, and 800 °C. The investigated thermal and mechanical properties include the thermal conductivity, specific heat, compressive strength, tensile strength, tensile ductility, and density. The effects of five mix proportioning variables on the material properties are evaluated, which include the water-to-binder ratio (0.24–0.36 by mass), sand-to-binder ratio (0.36–0.66 by mass), fly ash content (60%–75% by mass), polyvinyl alcohol fiber content (1.5%–2.2% by volume), and superplasticizer content (0.10%–0.15% by mass). Experimental results reveal significant dependence of the residual thermal and mechanical properties on temperature and the mix proportion, which can be attributed to a series of chemical and physical reactions that occur at elevated temperatures. This study can facilitate optimization of mix proportions of HPFRCCs for enhanced thermal and mechanical performance in fire or high temperature applications. [ABSTRACT FROM AUTHOR]

Aiming to increase sustainability in the field of construction, this study investigates possible alternative materials, considered as by-products, for the manufacture of greener low-strength concretes, intended for the manufacture of Concrete Masonry Units (CMUs); using sawdust in replacement of sand and wood ash and lime mud in replacement of cement. The by-products are characterized by means of physical and chemical analyses, to determine their potential use in concrete; then ten different concrete mixes, each with different amounts of by-products, and a reference concrete are tested. The effects of these by-products on the density, absorption, voids, compressive strength, thermal conductivity, thermal diffusivity, and specific heat of the concrete are all investigated. [ABSTRACT FROM AUTHOR]

This study investigated the effects of ammonium polyphosphate (APP) content on the mechanical, thermal and flammability properties of kenaf/polypropylene (KF/PP) and rice husk/polypropylene (RH/PP) composites prepared by melt mixing technique. Polyethyleneoctene grafted maleic anhydride (POE-g-MAH) has been used as compatibilizer. The PP/KF/APP and PP/RH/APP composites were investigated using flexural and impact tests, scanning electron microscope, thermogravimetric analysis (TGA), differential scanning calorimeter and limiting oxygen index (LOI) test. Flexural modulus of PP/KF/APP and PP/RH/APP composites significantly improved from approximately 1.1–2.5 and 0.9–2.1 GPa, respectively, by the addition of 10 phr APP. The flexural strength of the composites also increased by the incorporation of 10 phr APP. In addition, the impact strength of the PP/RH/APP composites increased above 10 phr APP content. From the TGA results, incorporation of APP into PP/RH and PP/KF composites increased the char residue and thermal stability of the composites. Furthermore, the addition of APP increased the flame retardancy of the PP/KF/APP and PP/RH/APP composites with a significant increase of LOI at 10 phr. [ABSTRACT FROM AUTHOR]

This paper aims at evaluating thermal and mechanical behaviors of concrete mixed with shape stabilized phase change material (SSPCM) in order to apply the concrete mixed with SSPCM for structural members. Toward that goal, material tests are performed on cylindrically shaped specimens having different water to cement ratios, SSPCM content, and temperature conditions. In addition, two different mixture methods are tested; the first is to add SSPCM to the concrete mixture, and the second is to replace the fine aggregate with the same amount of SSPCM. From the tests for thermal behaviors, it is observed that the thermal conductivity decreases and specific heat increases as SSPCM content increases. Regarding mechanical behaviors, the compressive strength and elastic modulus of concrete mixed with SSPCM decrease with SSPCM content, and the reduction rate is linearly proportional to the mass fraction of SSPCM to concrete. When the specimens are exposed to temperature higher than the melting point of the SSPCM, the compressive strength of the concrete is decreased. However, full recovery of the decreased strength is also observed when the heated specimens are cooled down to room temperature. Based on the experimental findings, an equation for calculating strength of concrete mixture is proposed and used to design mix proportions of concrete mixed with SSPCM. The material tests show that the specimens fabricated according to the proposed method satisfy the target strength. [ABSTRACT FROM AUTHOR]

Reactive powder concrete (RPC) is highly susceptible to serious damages and explosive spalling during high temperature owing to its dense microstructure. Over the past few years, the demand of RPC in construction industry increased due to ultra-high strength and durability requirements. This raises concerns about fire resistance of RPC. Recently, numerous studies have been carried out to explore the residual and hot-temperature performance of RPC. Within this framework, the experimental results about the thermal, mechanical and deformation properties of RPC at both test modalities are compiled and compared. Important mechanical properties focused in this paper are compressive strength, tensile strength, flexural strength, elastic modulus and stress-strain behaviour. Among thermal and deformation properties; thermal conductivity, specific heat capacity, mass loss, free thermal strain and load-induced thermal strain are discussed. Meanwhile, mechanism of fire induced spalling and its influencing factors like moisture content, water-binder ratio, fibres and supplementary cementitious materials are studied as well. A relationship among spalling critical temperature and standard cube compressive strength has been developed. Furthermore, the relationship among spalling resistant steel fibres dosage with standard cube compressive strength has been obtained. A comparison of compiled fire resistance data of RPC with existing code provisions is also presented. These code provisions are found to be more conservative for residual test data rather than hot-temperature test data. The residual strength of RPC after exposure to high temperature was relatively higher than hot-temperature strength at most temperature ranges. This study shows a lack of experimental data about deformation and thermal properties of RPC exposed to high temperature. Overall, those factors have been highlighted in the paper that improve high temperature performance of RPC. [ABSTRACT FROM AUTHOR]

The cementitious construction material, cemented paste backfill (CPB), is extensively used in underground mining operations worldwide. After the CPB is placed in the field, the evolution of its mechanical and thermal properties strongly affects its stability and the heat transfer within it. An experimental setup is designed to enable the curing of CPB samples under different stresses, filling rates, initial temperatures and drainage conditions as well as the monitoring of the changes in capillary pressure, temperature, amount of drained water and electrical conductivity in the CPB samples during curing. Furthermore, extensive testing is carried to investigate the combined effects of initial temperature, curing stress and drainage on the mechanical, microstructural and thermal properties of CPB. The obtained results reveal that these properties are strongly influenced by the initial backfill temperature, curing stress and drainage conditions, and their interactions. These can significantly affect the cement hydration, capillary pressure development and pore structure of CPB. [ABSTRACT FROM AUTHOR]

With the flourish development of energy-saving solutions for building, the demands of phase change material (PCM) modified building materials are urgently increasing. Herein, we report a novel route to prepare clay geopolymer mortar incorporated PCM by vacuum absorption method, where PCM is produced with paraffin as heat-absorbing material and expanded perlite as p supportive material by vacuum adsorption method. The paraffin immobilized in three-dimensional network structure during the process of phase change is evidenced by scanning electron microscope (SEM), different scanning calorimetry (DSC), compressive strength, dry density and thermal conductivity. The proportion of paraffin in the composite is 55.47% by mass, and the phase change temperature and latent heat were 35.59 °C and 96.77 J/g, respectively. The compressive strength, dry apparent density, and thermal conductivity coefficient were 8.0 MPa, 1678 kg/m 3 , and 0.46 W m −1 K −1 , respectively. [ABSTRACT FROM AUTHOR]

• Physico-mechanical properties of gypsum compounds with waste cellulose acetate (CA). • Waste CA fibres were extracted from discarded cigarette filters. • Slightly lighter composites were obtained by adding waste CA fibres. • Mechanical strength increased for most of the waste CA-containing composites. • Composites with waste CA fibres presented a lower thermal conductivity. The influence of waste cellulose acetate (CA) fibres in the physico-mechanical (i.e. density, surface hardness - Shore C, flexural and compressive strength) and thermal properties (i.e. thermal conductivity coefficient) of gypsum-based composites was evaluated in this study. Furthermore, complementary stereomicroscopy and scanning electron microscopy analysis were carried out. Lighter composites were obtained with ensuing incorporation of waste CA fibres. In comparison to the control material, an improvement on flexural and compressive strength, up to ∼9 % and ∼1 %, respectively was observed. Moreover, a slight declining trend in thermal conductivity was found with increasing replacement level (up to ∼16 % decrease). [ABSTRACT FROM AUTHOR]

• Effect of both crumb rubber and polypropylene fibers on properties of geopolymer mortar. • Crumb rubber enhances the ductility and toughness of geopolymer mortar. • Crumb rubber improves the thermal properties of geopolymer mortar. • Regression models accurately predict mechanical and thermal properties are introduced. Nowadays, geopolymers play an important role in developing eco-friendly construction materials to avoid the pollution that comes from the Portland cement industry. Geopolymers show enhanced mechanical properties while ductility tends to be relatively low. Moreover, the thermal properties of construction materials are important in terms of energy-saving and sustainability. On the other hand, by increasing the used rubber tires and with low recycling processes, these wastes become a serious environmental problem. So, this work is directed to develop and investigate enhanced rubberized geopolymer composites regarding ductility as well as thermal properties. To achieve these targets, reusing Crumb Rubber (CR) from used rubber tires as a partial replacement of sand by volume was investigated with (10 %, 20 %, and 30 %) replacement ratios and different CR particle sizes (0–1 mm, 1–3 mm, 4 mm, and 0–4 mm). Parallel with using CR, polypropylene fibers with different volume fractions of (0.5 %, 1.0 %, and 1.5 %) were implemented. The effect of CR content and size on the Physical, mechanical, and thermal properties have been investigated. Additionally, the effect of incorporating polypropylene fibers in rubberized geopolymer mortar has been studied. The results indicated that despite the mechanical properties of rubberized geopolymer mortars tend to be lower, the mode of failure, toughness, and performance under flexural due to the synergistic influence of rubber and fibers have been improved remarkably. Additionally, the results of the transient plane source method indicated that thermal conductivity, thermal diffusivity, and heat capacity have been significantly enhanced in terms of heat insulation. Incorporating 20 % CR with 1 % fibers increases the flexural toughness by 27.5 % more than the mix containing 1 % fiber only. Incorporating 30 % CR decreased the thermal conductivity by about 39.7 %. Furthermore, the regression analysis by developing numerous relationships was proposed. The results of the regression model revealed that the models developed were adequate in explaining the effect of the independent parameters on the responses. It will be helpful to the engineers in deciding the levels of the fibrous rubberized geopolymer composites parameters for desired performance properties serving some environmentally friendly construction applications. [ABSTRACT FROM AUTHOR]

• The effects of high temperature on LWC with carbon nanotubes (CNTs) and structural LECA as coarse aggregates are investigated • The addition of CNTs to LWC brings in an improvement of the tensile properties at high temperature • LWC containing CNTs exhibits a lower thermal conductivity, to the advantage of the insulating power of concrete in fire The effects of elevated temperature on lightweight structural concrete (LWC) containing Carbon Nanotubes (CNTs) and structural Lightweight Expanded Clay Aggregates (LECA) as a substitute for coarse aggregates are investigated. Mechanical properties such as compressive, indirect tensile strength (in splitting and bending) of a 7-day and 28-day structural LWC (with and without CNTs) have been evaluated under different temperature ranges from ambient temperature up to 800 °C. Moreover, in order to capture all aspects, along with characterizing the mechanical response of the concrete, thermal conductivity has also been measured to understand the thermal behavior of structural lightweight concrete. Hereafter, to bring together different results so that the similarities and differences can be seen, each achieved result from present research has been compared to that of literature. Results indicate that all mechanical properties of the structural LWC containing CNTs were improved at different temperatures compared to those without CNTs. The reasons for the improvement were interpreted by Scanning Electron Microscope (SEM). Moreover, thermal test results demonstrate a decrease in thermal conductivity to the advantage of possible high-temperature applications. [ABSTRACT FROM AUTHOR]

The purpose of this investigation was to evaluate the properties of bio-flour-filled composites. The composites used in this study were prepared from polypropylene, wood flour (WF) and cotton stalk bark (CSB). CSB was added with different concentrations (2.5 wt.%, 5 wt.%, 10 wt.%, 15 wt.%, 30 wt.%). Maleic anhydride grafted polypropylene (PP-g-MA) was served as a compatibilizer to increase the interfacial adhesion between the ingredients. Water absorption, morphology, mechanical and thermal properties were investigated. The results indicated that the flexural properties and tensile modulus of cotton stalk bark plastic composites (CSBPCs) were increased with the increasing concentration of CSB. However, the tensile strengths exhibited a negative correlation with the CSB content, which reached 32.9 MPa when the adding of CSB was 30 wt.%. The moisture absorption of CSBPC showed a higher value than that of neat PP, and it was increased with the increasing concentration of CSB. The thermal experiments showed that the decomposition temperatures of CSBPCs were higher than that of PP. [ABSTRACT FROM AUTHOR]

This paper presents the effects of two types of alkali activators (Na and K-based) on the residual mechanical properties of steel fibre reinforced geopolymer concretes (SFRGC) after exposed to various elevated temperatures and compared with those of steel fibre reinforced concrete (SFRC). Compressive strength, indirect tensile strength and elastic modulus of above three types of steel fibre reinforced concretes are measured after exposure to elevated temperatures of 200, 400, 600 and 800 °C. Results show that the SFRGC containing Na-based activators exhibited much higher residual compressive and indirect tensile strength at all elevated temperatures including at ambient condition than its K-based counterpart and SFRC. However, the retention of residual compressive strengths relative to ambient is comparable in both Na- and K-based SFRGC and both SFRGCs showed original (ambient temperature) compressive strength retention capacity up to about 500 °C temperature. In the case of indirect tensile strength, the K-based SFRGC showed ambient temperature strength retention capacity up to about 700 °C temperature with more than 60% increase in residual indirect tensile strength at 400 °C. In the case of elastic modulus the SFRC, however, showed slightly higher retention capacity than the SFRGC. Good correlations between the indirect tensile strength and the compressive strength and between the elastic modulus and the compressive strength of all three types of fibre reinforced concretes are observed. Existing model to predict the compressive and indirect tensile strengths of SFRGCs is found to underestimates the test results, however, it predicts reasonably well the elastic modulus of SFRGCs. New empirical equations to predict the compressive, indirect tensile strength and elastic modulus of SFRGCs are also proposed. Both SFRGCs also show negligible damage in terms of surface cracking after elevated temperatures heating compared to visible surface cracks in SFRC. [ABSTRACT FROM AUTHOR]

Basalt fiber-reinforced polymers (B) composite laminates have been extensively used over the last decade in externally strengthening of reinforced concrete (RC) slabs and beams in flexure and shear. Basalt fibers have higher thermal resistance, corrosion resistance, and ductility than the commonly used carbon (C) laminates. However, there is a lack of knowledge about the mechanical properties of such laminates and their hybrid combinations when exposed to elevated temperatures. This paper presents the results of an experimental program that studies the mechanical properties of carbon (C), basalt (B), and their hybrid combinations (BC, CBC, CCB, BBC, and BCB) of multiple layers at elevated temperatures. The experimental program consists of 140 coupon specimens were prepared and tested after being exposed to different temperatures ranging from 25 to 250 °C. The results showed that both the elastic modulus and the tensile strength of the C and B laminates degraded with the increase in temperature. However, the degradation was greater in the C composite sheets. Based on the experimental results, it was also observed that the mechanical degradation was the highest in C laminates, which reached to almost 90% at 250 °C. In addition, the elastic modulus and tensile strength values had shown that the BBC and B laminates had the highest mechanical performance when exposed to elevated temperatures. In addition, analytical models are proposed from the generated test data to predict the variation in the elastic modulus and tensile strength with temperature. The obtained results and proposed models can be used as input parameters in the analysis and design of externally strengthened members with such FRP laminates. This study strongly endorses the use of B and hybrid combination of B and C laminates in strengthening RC slabs and beams. [ABSTRACT FROM AUTHOR]

In this work, in order to investigate the reinforcement effects of organic montmorillonite (OMMT) modified epoxy mortar binders (EMBs), a series of OMMT/EMB composites with different OMMT loadings were prepared. The structure and thermal stability of OMMT were studied by X-ray diffraction (XRD), Fourier transform infrared spectrum, and thermogravimetric analysis (TGA). The effects of OMMT on the structure, glass transition, damping properties, thermal stability, mechanical properties and morphology of EMB were characterized by XRD, dynamic mechanical analysis, TGA, tensile test, and scanning electron microscopy. XRD results indicated that epoxy chains intercalated into the OMMT layers and led to the expansion of OMMT layer spacing. The presence of OMMT increased the glass transformation temperature, crosslink density of the neat EMB. Furthermore, the incorporation of OMMT improved the thermal stability of the EMB. The OMMT/EMB composites showed higher tensile strength and Young’s modulus than the neat EMB. Homogenous dispersion of OMMT in EMB matrix was observed. [ABSTRACT FROM AUTHOR]

High temperature resistance is one of the most important parameters which affects the durability and service life of materials. Due to synergistic interaction of different mechanisms, mechanical performance can be lowered especially for the multi-component composite materials exposed to high temperature. Standard or steam cured slurry infiltrated fiber concrete (SIFCON) and slurry specimens were subjected to 300, 600, 750 and 900 °C in the scope of present study. Exposing the specimens to 300 °C enhanced the mechanical performance, while higher temperatures have detrimental effects on the SIFCON composites such as the loss in the cross section of steel fibers and the destruction of C–S–H structure. Mechanical test results were in accordance with micro-structural and thermal analyses. [ABSTRACT FROM AUTHOR]

In this study, cement mortar with paraffin/expanded perlite materials was prepared by direct mixing method. The effect of paraffin/expanded perlite material content on mechanical and thermal properties of cement mortar were investigated. The experimental results showed that the paraffin was confined in the porous structures of expanded perlite by capillary force. The average mass percentages of paraffin in paraffin/expanded perlite material reached as high as 65%. It was a physical interaction between paraffin and expanded perlite. Compressive strength and flexural strength of cement mortar decreased with increasing amount of paraffin/expanded perlite materials. Cement mortar with 20 wt% paraffin/expanded perlite materials had good heat storage property and thermal stability compared to ordinary cement mortar. [ABSTRACT FROM AUTHOR]

The main objective of this paper is to demonstrate that it is possible to make precast concrete floor blocks with more than 50% replacement of natural aggregate with recycled aggregate made with crushed clay bricks and roof tiles. In first phase of the research, the physico-mechanical properties of concrete with recycled and with natural aggregate were tested. The second phase explored the properties of precast concrete floor blocks. Their geometrical, mechanical, thermal and acoustic properties were determined. Based on experimental research it can be stated that it is possible to make precast concrete floor blocks with recycled aggregate with the fulfilled thermal, cost and environmental requirements. [ABSTRACT FROM AUTHOR]

This article presents an investigation of the properties of natural fiber based composite building materials that is applicable for hot and humid climatic regions. These materials were made of cement mortar containing coconut coir fiber and oil palm fiber, both waste products from agricultural manufacturing in Thailand. They are intended to be used as roof sheet and siding to reduce heat transfer through buildings and energy conservation. The investigation focused mainly on the effects of both cellulose fibers on the physical, mechanical and thermal properties of products. Test results showed that increasing the percentage replacement of natural fibers tends to reduce the density, compressive strength and flexural strength of the materials. Fiber cement products mixed with coconut fiber yielded lower density than that of oil palm fiber. The mixtures of fiber cement products containing up to 15% of both natural fibers by weight of binder yielded the acceptable physical and mechanical properties. Furthermore, the thermal conductivity of the natural fiber cement sheets was 60% less than that of the control specimen. The results of this research can be used as a guideline for using agricultural residues to develop fiber cement products for residential building applications. [ABSTRACT FROM AUTHOR]

Polymer mortar with excellent mechanical strength and durability has been widely used in road pavement and other construction industry. In this study, two kinds of brucites, synthetic and natural brucites were incorporated in the epoxy mortar binders as flame retardants. The components and morphology of the two kinds of brucites were investigated. The flame retardancy of brucite-modified epoxy mortar binders was evaluated by the horizontal burning and limiting oxygen index tests. The influence of flame retardants on the rotational viscosity, the thermal and mechanical properties of epoxy mortar binders was determined by differential scanning calorimetry, thermogravimetric analysis, and universal test machine. Furthermore, the morphology of flame retarded-epoxy mortar binders was characterized by scanning electron microscopy. The addition of brucites significantly improved the flame retardancy, thermal stability and tensile strength of epoxy mortar binders. Especially in the case of the addition of 20 wt% synthetic brucites in epoxy mortar binders, from FH-3 to FH-1 reduction in the horizontal burning classification, 5.5% improvement in limiting oxygen index, 15% increment in tensile strength were obtained. [ABSTRACT FROM AUTHOR]

[Display omitted] • A total of 88 plastic composites were classified into six categories based on their filler type. • Plastic composites present materials (wt%), analysis methods, standards and sample dimensions. • Thermophysical properties (ρ, λ, Cp, volumetric specific heat) were reviewed and shown by plastic composite. • Compressive, tensile and flexural strengths were the three mechanical properties explored by category. • Explored plastic composite features summarize thermal conductivity range values from 0.02 to 2.23 W/(m·K). Plastic waste management represents a significant problem worldwide, but also, an opportunity for construction materials development. This manuscript explores plastic composite trends, emphasizing thermal and mechanical features. Data obtained from literature over 88 plastic composites were classified into six filler-based categories, 78% presented mechanical data, whereas only 40% provided thermal characterization. The explored features summarize thermal conductivity range values from 0.02 to 2.23 W/(m·K) and Compression Strength between 0.1 and 158 MPa within the recycled plastic composites repository with densities from 50 to 2100 kg/m3, similar to those considered conventionally a feasible possibility to reduce energy demand through low-energy architectural envelopes. [ABSTRACT FROM AUTHOR]

• Self-heating alkali activated slag mortars (AASMs) with GP are studied. • Degree of formation of electrically conductive GP paths in AAM matrix is analyzed. • Electrical, thermal and mechanical properties are determined. • Links between microstructure and functional properties are assessed. • Model formulas for compressive strength – porosity relations are developed. Alkali activated materials can be considered as eco-friendly substitutes of Portland cement-based composites which leads to their recent increasing use in the construction industry. In this paper, electrical, thermal, and mechanical properties of alkali activated slag mortars containing graphite powder (GP) in various dosage are analyzed and linked with microstructural characteristics. The use of GP in the amount of 8.75 wt% is found to lead to a good self-heating performance of up to 9.9 W. The electrical conductivity of 4.62·10−2 S/m, compressive strength of 22.7 MPa, flexural strength of 6.9 MPa, and thermal conductivity of 1.36 W/m·K present a satisfactory mix of properties for most self-heating applications. [ABSTRACT FROM AUTHOR]

Incorporation of phase change material (PCM) in building materials has been an important research topic in recent years. The use of PCM intends to increase the thermal inertia of buildings and reduce the consumption of energy for cooling and heating. This paper studies experimentally the mechanical and thermal properties of geopolymer mortar synthesized with low calcium fly ash and different amount of PCM. First the effect of incorporated PCM on the unit weight and compressive strength of geopolymer mortar was evaluated. Then scanning electron microscopy (SEM) imaging was performed to identify the change of micro structure of the geopolymer mortar after incorporation of PCM. The thermal properties of the geopolymer mortar containing different amount of PCM were also characterized using differential scanning calorimetry (DSC) analysis. Finally model tests were performed using small cubicles built with geopolymer mortar slabs containing different amount of PCM to evaluate the effectiveness of geopolymer mortar wall with incorporated PCM in controlling the heat flow and internal temperature. The results indicate that both the unit weight and compressive strength of the geopolymer mortar decrease slightly after PCM is incorporated, mainly due to the small unit weight and low strength and stiffness of the PCM. However, the compressive strength of geopolymer mortar containing up to 20% PCM is still sufficiently high for applications in buildings. The results also show that the incorporation of PCM leads to substantial increase of heat capacity and decrease of thermal conductivity of the geopolymer mortar and is very effective in decreasing the temperature inside the cubicles. Therefore, the geopolymer mortar with incorporated PCM can be used as building walls to effectively increase the thermal inertia of buildings and reduce the consumption of energy for cooling and heating. [ABSTRACT FROM AUTHOR]

The paper mainly aims to study the effect of the incorporation of barley straws and wood shavings on the physico-mechanical properties of sand concrete intended for the construction in arid zones. Basing on the study at fresh state, the experimental work has been firstly devoted to searching for optimal compositions of the composite. Then, a second study has focused on the physico-mechanical characterization of sand concrete without lignocellulosic materials. Finally, a special experimental program has been devoted to the study of sand concrete with lignocellulosic materials. The obtained results show that it is quite possible to develop a lightweight sand concrete by the incorporating, separately and in combination, of barley straws and wood shavings. Moreover, it has been noted that the combined addition of barley straws and wood shavings gives the best physico-mechanical results which were strongly confirmed by a microstructure study. With combined addition, the problem of shrinkage was relatively solved: decreases of about 11.76% and 39.02% were recorded in comparison with the cases where barley straws and wood shavings are taken separately. In addition, the thermal diffusivity has been reduced of about 35.47% with respect to the basic composition. Due to its higher deformability, the barley straw improves the toughness and ductility of sand concrete and reduces its dimensional variations. Indeed, the studied composites, offer to the local constructions important technical and economic interests: good thermal insulation and efficient energy saving and low cost of materials. [ABSTRACT FROM AUTHOR]

• Mechanical property parameters of ETFE membrane at different temperatures are given. • The thermal expansion coefficient of the ETFE membrane is given. • The thermal deformation model is given. • The thermal deformation mechanism is proposed. This study focused on the mechanical properties of the ethylene tetrafluoroethylene (ETFE) membrane at temperatures between −20 and 140 °C, the thermal expansion performance from the ambient temperature of 25 °C to 140 °C, and the thermal deformation performance from the ambient temperature of 25 °C to 80 °C. According to the experimental study, the mechanical properties, the glass transition temperature, the coefficient of thermal expansion (CTE), and the thermal deformation strain model of ETFE at different temperatures were obtained. Finally, the thermal deformation mechanism is proposed, namely that the thermal deformation strain is equal to the thermal expansion strain and elastoplastic strain produced by the change of the strain–stress relationship. [ABSTRACT FROM AUTHOR]

Highlights: [•] We compare mechanical properties of lightweight concrete with vermiculite and EPS. [•] Lower amount of lightweight aggregate and air-entraining provides higher strength. [•] Vermiculite lightweight concrete has lower thermal conductivity than with EPS. [•] EPS lightweight concrete has higher strength and is lighter than with vermiculite. [Copyright &y& Elsevier]

Highlights: [•] This paper reviews the feasibility of using PCM in concrete. [•] There are generally three probable means of PCM incorporation in concrete. [•] The three predominant are immersion, impregnation and direct mixing. [•] Method of PCM incorporation has a great influence on the properties of concrete. [•] The influence on the fresh, mechanical and thermal properties is reviewed. [Copyright &y& Elsevier]

• Raw and treated doum fibers were used to produce compressed earth brick (CEB). • The mechanical and thermophysical properties of CEB are investigated. • The reinforcement by doum fibers decreases density and increases water absorption. • The addition of fibers decreases thermal conductivity and compressive strength. • The use of doum fibers promises the production of an ecological building material. This work investigates the physical and mechanical properties of compressed earth brick (CEB) reinforced with raw doum fibers (RDF) and treated doum fibers (TDF). Firstly, the raw materials were characterized. Then CEB reinforced by fibers varying from 0 to 2% by mass were elaborated. The addition of RDF and TDF reduces the compressive strength by 25% and 35% respectively. However, the inclusion of fibers improves the thermal insulation of CEB and decreases its density of about 16%. The research finding indicates also that the capillarity absorption increases with the increase of fiber content. These results indicated that the use of doum fibers to produce ecological building materials has a promising future. [ABSTRACT FROM AUTHOR]

• Boron nitride-doped expandable graphite (EG) microcapsule (BN-PMEG) was prepared. • BN improves the thermal conductivity of microcapsule. • BN and EG form an expressway network for heat transfer. • High thermal conductivity BN -PMEG reduces the risk of combustion of natural rubber. The flammable feature limits the application of natural rubber in building fields. Although expandable graphite (EG) microcapsule has good compatibility with natural rubber (NR), the organic wall material of microcapsule has the disadvantage of low thermal conductivity and increases the risk of combustion of NR. In this study, EG microcapsule was prepared via in-situ polymerization (BN-PMEG) whilst its organic shell with high compatibility and thermal conductivity was developed by boron nitride (BN)-doped. The composite structure and thermal performances were analyzed via scanning electron microscope test (SEM), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TG). Following this, the cone calorimeter test, limiting oxygen index test, vertical burning test, time to ignition test, tensile strength and fracture test were used to describe the fire behavior and mechanical properties. The results indicate that the BN is embedded in the PMMA shell and the diameter of BN-PMEG is 20–50 μm. According to the mechanical property and thermal conductivity test, BN-PMEG have better compatibility with NR than expansible graphite and increases the thermal conductivity of NR composites. Our work provides a new choice for designing and applying rubber composite materials in buildings. [ABSTRACT FROM AUTHOR]

Highlights: [•] Lightweight EPS concrete was produced by partially replacing EPS beads with foams. [•] A noval method to evaluate homogeneity of concrete during setting was developed. [•] Segregation of EPS concrete was significantly reduced at an optimum foam content. [•] Strength of EPS concrete was enhanced by introduction of a proper amount of foam. [•] EPS foamed concrete is ductile and exhibits a high energy absorption capacity. [Copyright &y& Elsevier]

Abstract: Mechanical, hydric and thermal properties of lime–metakaolin plasters hydrophobized by zinc stearate added to the fresh mixture are analyzed in a wide range of hydrophobe dosage. The water absorption coefficient of analyzed plasters is found to decrease very fast with the increasing zinc stearate content in the mix, while both the compressive and bending strength decrease only moderately. The open porosity, water vapor diffusion properties and thermal properties are affected positively by the addition of zinc stearate. Taking into account the mechanical, hydric and thermal properties, together with the economical factors and recommendations of the supervisory authorities of architectural heritage on the properties of renovation renders, the lime–metakaolin plaster with the zinc stearate amount of 1% of the mass of binder can be considered as an optimal solution. [Copyright &y& Elsevier]

Abstract: This paper presents the results of an experimental study on the use of polyamide powder waste to produce a new lightweight plaster material with improved thermal properties. Plaster blends were prepared using different volumetric proportions of polyamide. The characteristics of the tests specimens were defined and tested by fixing the consistency at a good workability and then determining the mechanical properties, Shore C hardness and the water vapour permeability that correlates with the pore structure obtained with Mercury Intrusion Porosimetry (MIP). The compatibility of the interface zone of materials was analysed using Fast Scanning Electron Microscopy (FSEM), in order to define the effect of the polyamide on the microstructure of the lightweight plaster. Moreover, its thermal behaviour was examined by thermogravimetry and thermal conductivity analysis. Our results show that an increase in the amount of polyamide affects the properties of the plaster, decreasing its density and mechanical properties, as well as increasing its permeability and its thermal resistance. These results confirm that plasters produced with recycled polyamide are comparable to lightweight plasters made with traditional materials. [Copyright &y& Elsevier]

Abstract: An extensive set of parameters of several lime–metakaolin plasters, including basic material characteristics, mechanical and fracture-mechanical properties, durability characteristics, hydric parameters and thermal properties, is presented. In a comparison with the reference lime plaster without any additives, the experimental results show three- to five-fold increase in strength, about 25% decrease of water vapor diffusion coefficient, 20% decrease of water absorption coefficient and a very high increase of freeze/thaw resistance. Using the lime of very high purity in lime–metakaolin plasters (98.0% of CaO+MgO) is found preferable to lower-purity limes; the main differences are observed in the freeze/thaw resistance, mechanical and fracture-mechanical parameters. A comparison with two commercial renovation plasters shows that the only notable advantage of the best commercial plaster studied over the best lime–metakaolin plaster is in its lower moisture diffusivity but it can be matched relatively easily by using hydrophobization admixtures. Therefore, it can be concluded that the lime–metakaolin plasters can find a wider application range in the renovation of historical buildings in the future and may at least partially replace the current renovation plasters as a cheaper and equally effective solution. [Copyright &y& Elsevier]

Abstract: A wide set of parameters of concrete containing 10% of ground granulated blast furnace slag as Portland cement replacement involving basic material characteristics, mechanical and fracture-mechanical properties, durability characteristics, hydric and thermal properties and chloride binding characteristics is determined and compared with the parameters of reference Portland cement concrete with otherwise the same composition. The experimental results show that the replacement of Portland cement by even such a low amount of ground granulated blast furnace slag as environmental more friendly and still valuable alternative binder either affects positively or at least does not worsen in a significant way the substantial properties of hardened concrete mix. The mechanical and fracture-mechanical properties are found to be very similar as compared to the reference mix, the liquid water transport parameters of the mix containing slag are significantly better, the basic durability characteristics such as the frost resistance and corrosion resistance similar and very good, the resistance against de-icing salts slightly worse. These findings may be significant for the future use of slag in the countries where its available amount is decreasing and its more efficient use as a binder than it was common to date can appear necessary. [Copyright &y& Elsevier]