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Concrete stands as a fundamental material in the construction industry. However, it encounters challenges such as cracking, crumbling, or disintegration at elevated temperatures, attributed to high thermal stresses and low tensile strength. This study addresses these issues by reinforcing concrete samples with steel and polypropylene fibres, exposing them to temperatures ranging from 25 to 800°C, and conducting mechanical tests. In order to provide a comprehensive examination, a concrete mixture containing lightweight aggregate was also prepared and tested along with other mixtures. The test results showed that adding steel and polypropylene fibres enhanced or maintained compressive strength up to 200°C compared to the control sample. Furthermore, samples containing steel fibres exhibited the highest tensile strength across all temperatures. Notably, at 600°C and above, the lightweight concrete sample demonstrated comparable or superior compressive strength as well as tensile strength compared to the control sample. In addition, it was observed that polypropylene fibres began to melt at 400°C, leading to a decline in compressive and tensile strength in samples containing this fibre type at temperatures exceeding 400°C. [ABSTRACT FROM AUTHOR]

The recent emphasis on sustainability issues in construction materials has increased the interest to examine the effect of recycled aggregates on the performance of pervious concrete. This study investigated the effects of different types of recycled coarse brick aggregates (RCBAs), maximum RCBA size and using recycled fine brick aggregates (RFBAs) on the performance of pervious concrete. This has been done by testing void, density, compressive strength, splitting tensile strength, permeability, dust clogging and abrasion resistance. The quality of effluent passed through pervious concretes was also studied. According to the results, the usage of different types of RCBA decreased the compressive strength of pervious concrete, with the highest strength reduction of 55.3% which was obtained for 50% RCBA type A. A larger porous network of concretes by the incorporation of RCBA resulted in a higher permeability coefficient of up to 24.9%. Moreover, using RFBA in pervious concrete produces a much denser matrix and hence provides higher compressive and splitting tensile strengths and lower permeability coefficient. The permeability loss of pervious concretes due to dust clogging can also be decreased at 50% incorporation of different types of RCBA. Furthermore, results showed that RCBA types mainly influence the abrasion resistance of pervious concrete. Statement of Novelty: Different types of waste bricks may have different physical and mechanical properties which necessitated comprehensive experimental research about their performance in pervious concrete. To cover the gaps in this field, this research was conducted to investigate the effect of three major factors including (1) three different types of recycled coarse brick aggregates, (2) maximum aggregate size and (3) using recycled fine brick aggregates on the performance of pervious concrete. [ABSTRACT FROM AUTHOR]

The recycling of construction wastes holds significant importance both environmentally and economically. While extensive research has been conducted on aggregates derived from various wastes, the recycling of pervious concretes (PC) has been largely overlooked. This study addresses this gap by examining the porosity and mechanical properties of PC manufactured using aggregates obtained from recycled PC. The investigation focuses on three key factors: aggregate size (5/15, 10/15, and 15/25 mm size fractions), fiber inclusion (dosages of 0.1%, 0.2%, and 0.3% by volume), and aggregate type (limestone aggregate and recycled aggregate). Through image processing techniques, void characteristics including amount, structure, and homogeneity were quantified. Results indicate that the use of recycled aggregate led to a decrease in compressive strength ranging from 29% to 65%, depending on aggregate size fraction and fiber content. Porosity assessments revealed higher porosity in concrete utilizing recycled aggregate, with computer-based methods yielding values closely aligned with volumetric results. [ABSTRACT FROM AUTHOR]

Concrete surface crack detection is a critical research area for ensuring the safety of infrastructure, such as bridges, tunnels and nuclear power plants, and facilitating timely structural damage repair. Addressing issues in existing methods, such as high cost, lengthy processing times, low efficiency, poor effectiveness and difficulty in application on mobile terminals, this paper proposes an improved lightweight concrete surface crack detection algorithm, YOLOv8-Crack Detection (YOLOv8-CD), based on an improved YOLOv8. The algorithm integrates the strengths of visual attention networks (VANs) and Large Convolutional Attention (LCA) modules, introducing a Large Separable Kernel Attention (LSKA) module for extracting concrete surface crack and local feature information, adapted for features such as fracture susceptibility, large spans and slender shapes, thereby effectively emphasizing crack shapes. The Ghost module in the YOLOv8 backbone efficiently extracts essential information from original features at a minimal cost, enhancing feature extraction capability. Moreover, replacing the original convolution structure with GSConv in the neck network and employing the VoV-GSCSP module adapted for the YOLOv8 framework reduces floating-point operations during feature channel fusion, thereby lowering computational complexity whilst maintaining model accuracy. Experimental results on the RDD2022 and Wall Crack datasets demonstrate the improved algorithm increases in mAP50 by 15.2% and 12.3%, respectively, and in mAP50-95 by 22.7% and 17.2%, respectively, whilst achieving a reduced model computational load of only 7.9 × 109, a decrease of 3.6%. The algorithm achieves a detection speed of 88 FPS, enabling real-time and accurate detection of concrete surface crack targets. Comparison with other mainstream object detection algorithms validates the effectiveness and superiority of the proposed approach. [ABSTRACT FROM AUTHOR]

This paper presents linking computational research of the multilayer structure of the cladding of a three-layer panel made of highly porous polystyrene concrete developed using a new technology in comparison with traditional ones. The calculation of the thermal efficiency of the exterior fence was carried out in three stages, where the thermal regime was calculated from the values of temperature fields in the ELCUT 6.6 system, and the humidity and air modes were determined by the analytical method in the Maple system. The territory of central Kazakhstan (Karaganda) was selected as the research region, where the research showed that equating the thickness by the values of the actual and required heat transfer resistances of traditional multilayer structures to the developed one, the thickness of traditional structures increases from 3.09% to 27.83%. Moisture accumulation relative to the developed one occurs in all the studied structures. Thus, if in some cases of traditional structures moisture is collected by 2.61% and 9.48% less, in others moisture is collected by 27.94% and 119% more. However, the value of evaporated moisture during the drying period showed that all the moisture will evaporate during the specified period. Thus, all the structures meet the conditions for the inadmissibility of moisture for the annual period and the period of moisture accumulation. Moreover, the values of the actual and required permeabilities to air satisfy the condition, which affected the values of the temperature fields taking into account air filtration; the developed structure showed a positive effect for this value, and in traditional structures, the value of τ i n t decreased to 1.35 °C depending on the option. The analytical results of the thermal inertia values of the developed and traditional multilayer structures showed that the developed structure exceeds traditional ones by up to 30.04% depending on the option, which is positive in the cold period. It was also found that the market prices of all traditional structures exceed the developed one by 1.2–2.5 times, depending on the design, which also emphasizes the positive aspects of the new design. Thus, the findings of this research will positively complement the catalog of products of external multilayer cladding structures made of effective materials and can be used by research communities and design organizations in the design of residential buildings. [ABSTRACT FROM AUTHOR]

Ceramsite concrete is one of the most widely used lightweight concretes at present. Although mechanical properties of ceramsite concrete have been extensively discussed, its permeability characteristics are neglected in previous studies. Considering the importance of permeability resistance to concrete, the permeability grade and residual compressive strength after permeability of ceramsite concrete are analyzed in this study. The influence of ceramsite content and size on the permeability grade and residual strength of ceramsite concrete were investigated by the orthogonal experimental method. To further understand the above influence, an improved Bayesian framework for small sample data is also established to analyze the permeability grade and residual strength. Results show that the water–binder ratio and the content of 20–30 mm ceramsite aggregates are the most and least significant influencing factors affecting the permeability characteristics, respectively. The 5–10 mm and 10–20 mm ceramsite aggregates play secondary roles. Increasing 5–10 mm and 10–20 mm ceramsite aggregates is not helpful for improving the permeability resistance of ceramsite concrete. Compared with the orthogonal method, the proposed Bayesian framework is a useful tool for revealing the effects of various factors, which can cut the time cost and provide parameter visualization for the analysis process. Results show that the permeability resistance and residual strength of ceramsite concrete are improved significantly under optimal conditions. The permeability grade and residual strength are increased 200% and 80.3%, respectively. In addition, the residual strength may be more suitable for evaluating the permeability characteristics than the permeability grade. [ABSTRACT FROM AUTHOR]

This study examines the utilization of granite stone-crushing waste in the production of porous concrete, with a particular emphasis on the influence of aggregate composition and cement paste layer thickness on the material's strength and density. Two types of aggregates were employed in this study: granite crushing screenings and granite crushed stone. The impact of aggregate grain size on the properties of porous concrete properties was investigated, and it was found that the use of granite screenings (2.5–5 mm) resulted in superior concrete characteristics compared to granite crushed stone (5–10 mm). This study puts forward a method for optimizing the composition of porous concrete to achieve an optimal balance of compressive strength and density. A method for the design of porous concrete was proposed, incorporating experimental results and the dependencies of strength on the water/cement ratio (W/C). Equations were developed to predict concrete strength based on W/C and cement paste layer thicknesses (CPLTs). The method provides preliminary mix proportions, which should be validated and adjusted for the final design. The findings demonstrate the potential for utilizing stone-crushing waste to produce environmentally sustainable and high-quality porous concrete. [ABSTRACT FROM AUTHOR]

This paper presents experimental and numerical investigations on the behavior of eccentrically loaded lightweight aggregate concrete encased steel (LWACES) columns after exposing to elevated temperatures. Sixteen concrete encased steel (CES) columns were considered in the study, 12 of which were exposed to elevated temperature then eccentrically loaded up to failure at different eccentricity ratios. The effect of temperature on the load–displacement relationships, failure load, and failure modes of the concrete encased steel (CES) columns was monitored and evaluated. Experimental results have shown that as the temperature increases, the load bearing capacity of the CES columns decreased. It has also been showed that, at high temperature, the normal‐weight concrete encased steel (NWCES) columns experienced larger degradation of the load bearing capacity compared to that of LWACES columns. Also, this study presents a numerical simulation of the behavior of LWACES columns at elevated temperatures with eccentric compressive load. The numerical model was implemented in conducting parametric study to understand the effect of temperature distribution, concrete cover, eccentricity ratio, and high temperature levels on the behavior of the thermally exposed (CES) columns. Numerical results have revealed that, at temperature value of 500°C, the ultimate capacity of LWACES with eccentricity ratios of 0.75, and 1 has decreased by 17%, and 23%, respectively, compared to that of the column with eccentricity ratio of 0.5. [ABSTRACT FROM AUTHOR]

Lightweight concrete offers numerous advantages for modular construction, including easier construction planning and logistics, and the ability to offset additional dead loads induced by double-wall and double-slab features. In a previous study, authors proposed incorporating lightweight aggregate into foamed concrete instead of adding extra foam to achieve lower density, resulting in lightweight concrete with an excellent strength-to-density ratio. This paper further investigated the performance aspects of foamed concrete with lightweight aggregate beyond mechanical strength. To evaluate the effect of aggregate type and foam content, three mix compositions were designed for the lightweight concrete. Specimens were prepared for experimental tests on thermal conductivity and drying shrinkage of lightweight concrete. Results showed that while both the increase in foam volume and the incorporation of lightweight aggregate led to higher drying shrinkage, they also contributed to improved insulating properties and reduced potential of cracking. Using typical multi-storey modular residential buildings in Hong Kong and three other Chinese cities as case studies, simulations were performed to assess potential savings in annual cooling and heating loads by employing the proposed lightweight concrete. These findings demonstrate the practical benefits of using foamed concrete with lightweight aggregate in modular construction and provide valuable insights for further optimization and implementation. [ABSTRACT FROM AUTHOR]

Engineering applications including pervious concrete require effective packing of aggregates to optimize strength. Size and shape distribution of aggregates significantly affect the performance. Computational methods numerically represent shape of aggregates, from image analysis, the effectiveness of has not been compared and verified. This study aims to analyse the representability of shape aspects of aggregates by different computational methods. Crushed aggregates were grouped into 5 clusters, and each group was milled in a Los Angeles machine for different degrees (0–2000) to induce morphological changes on the aggregates. Aggregates ranging from 5 to 30mm in diameter were obtained (7191 in total). imageJTM, was used to compute dimensions and shape factors of aggregates from 14 computational methods. Statistical tests, Pearson's Correlations and Principal Components Analysis and machine learning classification tools, Decision-tree, Random-Forest, Naïve-Bayes, Support-Vector-Machines, K-Nearest-Neighbours and Perceptron were employed to assess. In conclusion, no shape factor could be singularly used to numerically represent the morphological changes on aggregate particles but a combination of shape factors is required. Data matrix had three primary dimensions. Combination of Circularity, Kumbrein-Solidity and Barksdale-Shape-Factor yield best representation of aggregate shape. Regression Tree classification method had the highest accuracy (0.9) in classifying milled and unmilled aggregates. [ABSTRACT FROM AUTHOR]

Porous asphalt concrete (PAC) is a low-impact medium with strong stormwater management capabilities. However, the air voids inside the PAC mixture will gradually be clogged due to sediment entering the interior of the PAC pavement in the service period. Meanwhile, the permeability of PAC pavements can be partially restored using cleaning equipment. This study investigates the changes in microscopic void characteristics of PAC under the effect of clogging and cleaning. Three kinds of PAC specimens with different void content were clogged by aeolian sand and cleaned by high-pressure water washing after complete clogging, in which the air void content, the shape parameters (roundness and aspect ratio), number, equivalent diameter, fractal dimension of air voids for the PAC mixes were quantified by X-ray computed tomography (CT) and image processing techniques before and after clogging and cleaning. Moreover, a relationship between air void microparameters and measured air void content (volume method) was established. It was found that air void shape, air void content, air void number, and equivalent diameter had a significant impact on the clogging and cleaning effect of PAC pavement, but the fractal dimension did not have a considerable impact. The migration depth of the clogging material increased gradually with the increase of air void content, and the most severe clogging was at about 10 mm from the top surface. The air void number within 1 mm increased significantly due to particle clogging. Before the construction of the road, some microscopic void parameters of PAC will be predicted from air void content measured by volume method, and combined with the results of local clogging particle size distribution, a reasonable PAC gradation will be selected to generate much larger voids than the clogging particles to improve the anticlogging performance of PAC pavement. [ABSTRACT FROM AUTHOR]

The mechanical properties of porous concrete, such as strength and durability, are significantly influenced by moisture transport, particularly in the case of recycled aggregate concretes. The pore distribution and pore size of the concrete, as well as the ambient temperature in the surrounding environment, exert a significant influence on the moisture transport. This paper establishes the fractal Fick’s law, the fractal Darcy law, and the fractal Richards equation. In conclusion, a fractal model for the diffusion and permeability in porous concrete is established. This study examines the mechanisms of moisture diffusion and water permeability in concrete. The comparison of the theoretical prediction with the experimental data indicates a high degree of congruence, thereby suggesting that the concrete’s relative humidity response can be predicted by the established model. This provides a foundation for the optimal design of concrete with required mechanical properties in special applications. [ABSTRACT FROM AUTHOR]

This paper proposes a structure for concrete composite materials for electromagnetic interference shielding applications. It comprises an array of helical-shaped conductive particles as chiral additives. Unlike the previous studies using large quantities of conductive additives, this study provides a lightweight concrete composite due to the utilization of a small number of additives with a high level of shielding effectiveness in a wide frequency range. The heart of the proposed structure lies in leveraging the evanescent wave propagation in a circular waveguide, resulting in considerable shielding effectiveness. Under particular conditions, the helical particles can imitate a below-cutoff cylindrical waveguide and its dominant mode surface current on the helical wire. This phenomenon significantly attenuates the transmitted power from the array of helical particles in its resonance frequency range. Besides presenting the composition that exploits the magnetoelectric properties of the particles, this paper compares it with a traditional concrete composite, including randomly distributed sinusoidal steel rods. This second approach is examined using both experimental measurement and full-wave simulation methods. The results of this study indicate that the appropriate geometry of the conductive additives, in this case, chiral particles, and their arrangement in a regular array rather than a random distribution can enhance the efficiency of the conductive additives. This idea paves the way for more robust, efficient, and lightweight concrete composite materials, thanks to the recent advances in modern civil engineering manufacturing methods. [ABSTRACT FROM AUTHOR]

Self-Compacting Concrete (SCC) is a concrete with high workability. It fills the molds and passes between the narrow openings of reinforcing steel bars without the need for any mechanical pressure or compaction and without the need of a vibrator. Structural Lightweight Self Compacting Concrete (SLWSCC) is an innovative concrete developed in recent years. This concrete type combines the characteristics of lightweight concrete and SCC. This study focused on preparing the appropriate mixture to obtain SLWSCC by using Lightweight Expanded Clay Aggregate (LECA) as a volumetric partial replacement of coarse aggregate by 20, 40, 60, and 80%, reinforced by volumetric ratios of single and hybrid Micro steel Fiber (MF) and Hooked steel Fiber (HF) of 1.5 MF, 0.75 HF+0.75 MF, 1 HF+0.5 MF, and 1.5 HF (%) to evaluate the fresh properties through slump flow, T500mm, V-funnel, L-box, and segregation tests. The results showed that all mixtures fell within the limits of EFNARC/2005. It was found that single and hybrid fiber addition reduces slump flow, L-box, and segregation, while the T500mm and V-funnel values increased. The hard properties of SLWSCC reinforced by fibers, such as compressive strength, flexural strength, splitting tensile strength, oven dry density, and water absorption were studied. The addition of fibers raises compressive, splitting tensile, and flexural strength, with the maximum augmentation of 21.4, 43.4, and 53.8%, respectively, occurring when adding 1 HF + 0.5 MF. The highest value of oven dry density was acquired when adding 1.5 MF and the highest water absorption rate was acquired after the addition of 1.5 HF. [ABSTRACT FROM AUTHOR]

Although pervious reduces surface runoff and replenishes groundwater resources, industrial applications are hindered by uncertainty in properties during mass productions. Most experimental studies correlated design parameters to performance parameters predominantly analysing porosity measured from water replacement method. This explains only a fraction of porosity and leads to inappropriate correlations between the influencing parameters. This study quantified porosity using a novel image analysis. 480 samples of pervious concrete were cast varying aggregate to cement ratio and compaction levels and performance parameters such as, wet-density, compressive strength, apparent, actual and effective porosities were assessed. The developed novel image analysis method facilitates accurate computation of porosity and actual, apparent and effective porosities was analysed quantified and optimised. An optimum A/C ratio was observed as 4.0 corresponding to 30 blows of compaction and a resultant actual porosity of approximately 0.2. Further the study establishes relationships between different types of porosities and their performance implications. [ABSTRACT FROM AUTHOR]

Geopolymer concrete (GPC) is emerging as a sustainable alternative to conventional Portland cement-based concrete due to its significantly reduced carbon footprint and enhanced durability. To mitigate the environmental hazard posed by the disposal of fly ash (FA) and ground granulated blast furnace slag (GGBS) waste and reduce cement consumption, effective promotion of the geopolymerization technique is necessary. Incorporating sintered fly ash coarse aggregate (SFA) in GPC makes the concrete light in weight. This study involves the synthesis of geopolymer technology using FA and GGBS, as the primary source material. Due to the lack of an appropriate mix design method for using SFA in GPC, their application as a structural concrete is scanty. By using FA and GGBS with 100% SFA, a novel mix design methodology that offers greater simplicity and consistency is established in the present study. The proposed method is further verified by developing different concretes with alkali content to binder (AC/B) ratios ranging from 0.3 to 0.8. Fresh densities range between 1860 and 1930 kg/m3 and maximum compressive strength of nearly 50 MPa was attained after 28 days of ambient curing. The binder penetration and internal curing in SFA indicate that GGBS and FA have a superior synergistic effect on the efficacy of lightweight GPC using SFA. [ABSTRACT FROM AUTHOR]

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The energy consumption of buildings, particularly for space heating and cooling, is a major global concern. It accounts for a substantial portion of household energy use and varies based on environmental factors and climate conditions. Environmental factors highly influence energy-saving strategies of buildings in different climate areas. Addressing this challenge necessitates innovative approaches to building design and materials. This study aims to explore the energy performance of different walling materials in varying climates, including desert, subtropical, and tropical regions. Using transient systems simulation program multi-zone software, simulations were conducted on five room models with ten different walling materials. Notably, autoclaved aerated concrete and cellular lightweight concrete consistently demonstrated better performance in both Kuwait and Australia, resulting in reduced cooling and heating demands. The study emphasizes the significance of selecting building materials based on local climate conditions. It highlights the potential for future exploration of advanced materials like phase change materials and cool roofs. By considering local climate conditions, energy-efficient buildings can be constructed. Future research should focus on advanced materials to further enhance energy efficiency. [ABSTRACT FROM AUTHOR]

The utilization of recycled materials in concrete technology has gained significant attention in recent years, promoting sustainability and resource conservation. This paper investigates the behavior of lightweight self-compacting concrete (LWSCC) with recycled tire steel fibers (RTSFs). The effects of RTSFs on the flowability of the composite material and its density were assessed. The mechanical properties of the developed material were examined and beam tests were performed, aiming to assess its feasibility for structural applications. The compressive and tensile strengths were determined to evaluate the mechanical properties of the developed concrete mixtures. The beam tests were conducted to assess the flexural behavior of the beam specimens. Three different steel fiber contents of 0, 0.5, and 1% volumetric fractions of concrete were used in this study. The test results indicate that incorporating the fibers did not negatively impact the flowability and density of the LWSCC mixtures. In addition, the use of RTSFs enhanced the tensile strength of the developed concrete mixtures, where fibrous concrete showed increases in the splitting tensile strength in the range of 38 to 76% over that of non-fibrous concrete. On the other hand, the compressive strength of the mixtures was not affected. The test beams with RTSFs exhibited improved flexural performance in terms of delaying and controlling cracking, enhancing ultimate load, and increasing ductility. Compared with the control non-fibrous beam, the increases in the cracking load, ultimate load, and ductility index were up to 63.8, 9.3, and 16%, respectively. The test results of the beams were compared with theoretical predictions, and good agreement was found. [ABSTRACT FROM AUTHOR]

The bond strength at the interface zone between two concrete sections plays a critical role in enhancing long-term durability, ensuring that both materials perform homogenously. Ensuring compatibility at the interfaces between repair and concrete materials is one of the most challenging aspects of constructing composite systems. Despite various studies, a comprehensive understanding of the engineered cementitious composite (ECC) bonding mechanism at the repair interface is still limited. The objective of this research is to identify the interfacial properties between lightweight concrete (LWC) and engineered cementitious composite (ECC) with varying fiber dosages of polyvinyl alcohol (PVA) and glass fibers under different surface roughness conditions. The study tested LWC-ECC specimens in direct shear using slant shear and bi-surface shear tests, recording the maximum shear stress at failure. Two grades of LWC—normal-strength lightweight concrete (NSLW) and high-strength lightweight concrete (HSLW)—were used as substrates, while the ECC overlays contained varying fiber dosages: 2% PVA, 1.5% PVA with 0.5% glass, 1.0% PVA with 1.0% glass, and 0.5% PVA with 1.5% glass. The surface conditions considered included grooved and as-cast substrates. The results indicated that the highest bond strength was achieved by specimens with 1.5% PVA and 0.5% glass fiber, with a maximum shear strength of 24.05 MPa for grooved HSLW substrates. Interface roughness had minimal impact on shear strength for NSLW substrates but significantly affected HSLW substrates, with bond strengths varying from 13.81 MPa to 24.05 MPa for grooved surfaces. This study demonstrates the critical role of fiber dosage and surface roughness in enhancing the bond performance of composite materials. [ABSTRACT FROM AUTHOR]

The utilization of dredged sediment (DS) as a transformative material in building applications presents an ideal consumption strategy. This study endeavors to create a novel ceramsite lightweight aggregate (LWA) through the co-sintering of DS and rice husks (RHs), further integrating this LWA into the construction of pervious concrete. Results revealed that the optimum production procedure for the DS-based LWA incorporated a 21% RH addition, a sintering temperature of 1100 °C, and a sintering duration of 21 min. Notably, the optimal ceramsite LWA, denoted as SDC-H, exhibited a cylinder compressive strength of 28.02 MPa and an adsorption efficiency for Pb2+ of 94.33%. Comprehensive analysis (encompassing bulk density, cylinder compressive strength, water absorption, and the leaching concentrations of heavy metals) confirmed that SDC-H impacted the specification threshold of high-strength light aggregate derived from solid waste (T/CSTM 00548-2022). Substituting 50% of SDC-H led to a diminution in the mechanical properties but an improvement in the dynamic adsorption capacity of the innovative pervious concrete, registering a mechanical strength of 26.25 MPa and a cumulative adsorption capacity for Pb2+ of 285 mg/g. These performances of pervious concrete containing 50% SDC-H might correlate with the evolution of an interconnected and open-pore structure. [ABSTRACT FROM AUTHOR]

Disposal of water treatment sludge (WTS) has become an important issue of global environmental concern due to problems and costs. This study explored the feasibility of cold-bond methodology to produce an eco-friendly core–shell lightweight aggregate (LWA) from WTS, expanded perlite (EP), and cement. The effect of cement and WTS content on the properties of the LWA was studied. The findings revealed that the crushing strength, loose bulk density, 24-h water absorption, and 28-d water absorption of produced LWA ranged from 0.45 to 3.1 MPa, 1.05 to 1.25 g/cm3, 12.4 to 22%, and 22 to 27%, respectively. In addition, increasing the WTS content in the shell has a positive impact on the pH of the produced LWA. Furthermore, the SEM microstructure graphs revealed the efficient interference in the LWA particles between the cement–WTS composite and the perlite. The results also prove the possibility of using the produced LWA to produce structural lightweight concrete, with compressive strength, splitting tensile strength, and dry density of 24 MPa, 2.98 MPa, and 1840 kg/m3, respectively, with a consistent thermal conductivity of 0.72 W/m K and good acoustic insulation. [ABSTRACT FROM AUTHOR]

Research into lightweight structural concrete using volcanic tuff is of great importance to the construction industry. These materials have excellent thermal insulation properties, which helps improve the energy efficiency of buildings. A three-factor experimental design was used to build the statistical model. The test methods used were methods for determining the crushability of volcanic tuff, determining the average density, compressive strength and thermal conductivity of lightweight structural concrete. The influence of basalt fiber on the properties of lightweight structural concrete has been determined. The optimal compositions of lightweight structural concrete using tuff have been selected. The compressive strength of lightweight structural concrete reached 32.0 MPa. The average density range is 1754.6–2114.0 kg/m3. Good thermal conductivity values were obtained in the range of 0.653–0.818 W/m·K. The article obtained the optimal compositions of lightweight structural concrete using volcanic tuff as a filler. [ABSTRACT FROM AUTHOR]

Lightweight aggregate concrete, known for its light weight, thermal insulation, and excellent durability, has garnered significant attention and is considered an ideal material for lightweight ultra-high-performance concrete. Previous research has discovered that prewetting lightweight aggregates can continuously release water during the setting and hardening process of concrete, providing internal curing. However, the moisture release behavior of prewetted lightweight aggregates under different temperature and humidity conditions, as well as their internal curing mechanisms in low water–cement ratio mixtures, remains unclear and requires further investigation. In response to environmental sustainability, this study utilizes industrial waste γ-C2S to produce a high-strength carbonized γ-C2S lightweight aggregate (CC) and primarily compares the water absorption and release characteristics of three different types of lightweight aggregates, focusing on the influence of curing temperature and humidity on the water release behavior of the prewetted CC and establishing a water release model for the prewetted CC in cement-based materials. The experimental results indicate that the water absorption rates of the self-made high-performance lightweight aggregate (CC), magnesian lightweight aggregate (MC), and shale lightweight aggregate (SC) conform to the typical Boxlucas equation. In an air environment, the CC has the longest water release duration, followed by the MC, with the SC being the fastest. The water storage performance of the prewetted SC was poor, while the 100% prewetted CC exhibited better water storage during the mixing stage. When the CC is 100% prewetted, it can significantly increase the free water content in the interfacial transition zone, aiding in the hydration of the interfacial transition zone and enhancing the efficiency of shrinkage compensation by the expansive agent. This improvement contributes to the mechanical strength and volumetric stability of cement-based materials. [ABSTRACT FROM AUTHOR]

The construction industry is responsible for a significant share of global material consumption, including natural resources. Therefore, the United Nations Sustainable Development Goal 12.2 on sustainable management and efficient use of natural resources cannot be achieved without significant advances and contributions from the construction sector. Furthermore, various materials used by the construction industry contribute to the development and expansion of the LEED (Leadership in Energy and Environmental Design) system. LECA (Light Expanded Clay Aggregate) is one such material that enhances LEED performance through its key benefits, including lightness, thermal insulation, sound insulation, and fire resistance. One of the most effective methods for reducing the weight of concrete is the incorporation of lightweight aggregates, and the advantages of LECA include lessening loads and enabling reduced cross-sections, directly improving the sustainability of the built environment via reduced materials consumption. This study aims to develop a prediction model for the compressive strength of LECA-incorporated concrete through a meta-analysis. More than 140 data points were compiled through literature via 15 separate studies, and results were analyzed to conduct the meta-analysis. Moreover, an experimental program was carried out to verify the model and evaluate its accuracy in predicting compressive strength. Results from the developed model and the experimental program were in accordance with concrete having lower compressive strengths compared to those at high strength values. Likewise, more accurate results were obtained for concrete mixes that have w/b ratios of 0.5 or higher. Concrete mixes that have higher amounts of LECA by volume of concrete yielded more accurate results when using the prediction model. A sensitivity analysis was carried out to quantify the impact of several parameters on the compressive strength of LECA concrete. [ABSTRACT FROM AUTHOR]

Lightweight aggregates are a material used in many industries. A huge amount of this material is used in construction and architecture. For the most part, lightweight construction aggregates are obtained from natural resources such as clay raw materials that have the ability to swell at high temperatures. Resources of these clays are limited and not available everywhere. Therefore, opportunities are being sought to produce lightweight artificial aggregates that have interesting performance characteristics due to their properties. For example, special preparation techniques can reduce or increase the water absorption of such an aggregate depending on the needs and application. The production of artificial lightweight aggregate using various types of waste materials is environmentally friendly as it reduces the depletion of natural resources. Therefore, this article proposes a method of obtaining artificial lightweight aggregate consolidated using two methods: drum and dynamic granulation. Hardening was achieved using combined methods: sintering and hydration, trying to maintain the highest possible porosity. Waste materials were used, such as dust from construction rubble and residues from the processing of PET bottles, as well as clay from the Bełchatów mine as a raw material accompanying the lignite overburden. High open porosity of the aggregates was achieved, above 30%, low apparent density of 1.23 g/cm3, low leachability of approximately 250 µS. The produced lightweight aggregates could ultimately be used in green roofs. [ABSTRACT FROM AUTHOR]

Gold tailings is formed as an industrial waste during gold mining and processing. The aim of the current study is to use it to prepare foamed concrete as subgrade filler. The effect of wet density (600, 700 and 800 kg/m3) and tailings content (15, 30, 45 and 60 wt%) on fluidity, compressive strength, elastic modulus, drying shrinkage, freeze–thaw resistance, hydration heat and pore structure were investigated. It was found that incorporating tailings into foamed concrete decreases the compressive strength as tailings adversely affected the pore structure, resulting in increased porosity, enlarged and connected pores, and reduced sphericity. To meet the requirement of subgrade filler, the tailings content was limited to 30 wt% when the designed wet density was 600 kg/m3 and it was 45 wt% when the wet density increased to 700 and 800 kg/m3. Nevertheless, increasing the tailings content effectively reduced the drying shrinkage and early age hydration heat which are favorable for massive foamed concrete construction. Besides, the incorporation of gold tailings is helpful to the freeze–thaw resistance of 600 and 700 kg/m3 foamed concrete for application in seasonal frozen areas. [ABSTRACT FROM AUTHOR]

This study compares the workability, mechanical, and thermal characteristics of structural self-compacting lightweight concrete (SCLWC) formulations using pumice aggregate (PA), expanded perlite aggregate (EPA), fly ash (FA), and silica fume (SF). FA and SF were used as partial substitutes for cement at a 10% ratio in various mixes, impacting different aspects: According to the obtained results, FA enhanced the workability but SF reduced it, while SF improved the compressive and splitting tensile strengths more than FA. EPA, used as a fine aggregate alongside PA, decreased the workability, compressive strength, and splitting tensile strength compared to the control mix (K0). The thermal properties were altered by FA and SF similarly, while EPA notably reduced the thermal conductivity coefficients. The thermal conductivity coefficients (TCCs) of the K0–K4 SCLWC mixtures ranged from 0.275 to 0.364 W/mK. K0 had a TCC of 0.364 W/mK. With 10% FA, K1 achieved 0.305 W/mK; K2 with 10% SF reached 0.325 W/mK. K3 and K4, using EPA instead of PA, showed significantly lower TCC values: 0.275 W/mK and 0.289 W/mK, respectively. FA and SF improved the thermal conductivity compared to K0, while EPA further reduced the TCC values in K3 and K4 compared to K1 and K2. The compressive strength (CS) values of the K0–K4 SCLWC mixtures at 7 and 28 days reveal notable trends. Using 10% FA in K1 decreased the CS at both 7 days (12.16 MPa) and 28 days (22.36 MPa), attributed to FA's gradual pozzolanic activity. Conversely, K2 with SF showed increased CS at 7 days (17.88 MPa) and 28 days (29.89 MPa) due to SF's rapid pozzolanic activity. Incorporating EPA into K3 and K4 reduced the CS values compared to PA, indicating EPA's lower strength contribution due to its porous structure. [ABSTRACT FROM AUTHOR]

In order to improve structural fire-resistant behaviors, this paper designed a two-layer functionally graded ultra-high performance concrete (FGUHPC) structure composed of a UHPC layer and a lightweight aggregate concrete (LWAC) layer. UHPC layers are adopted to provide structural bearing capacity and protected by LWAC layers from elevated temperature. Splitting tensile tests and three-point flexural tests were conducted under ambient and elevated temperatures to evaluate interfacial bond performance and flexural bearing capacity, where two interfacial treatments were adopted and compared. The experimental results revealed that FGUHPC members exhibited good integrity during heating, no explosive spalling occurred and the maximal temperature at interfacial regions was 266°C. The interfaces showed desirable bond performance under ambient temperature while the splitting tensile strength was decreased by around 85% in the case of high temperature. Flexural test results indicated that the structural stiffness would be reduced by around 42% under elevated temperature, as a result, the maximal deflection was increased from 2.5 mm to 3.7 mm. SWM could significantly improve interfacial bond performance and prevent debonding failure of specimens at the postfire state, leading to higher structural bearing capacities. The bearing capacities of specimens with and without interfacial treatments were 42.7 kN and 38.4 kN respectively under ambient temperature, which remained about 88% after elevated temperature. [ABSTRACT FROM AUTHOR]

This work discusses the applicability of lightweight aggregate-encapsulated n-octadecane with 1.0 wt.% of Cu nanoparticles, for enhanced thermal comfort in buildings by providing thermal energy storage functionality to no-fines concrete. A straightforward two-step procedure (impregnation and occlusion) for the encapsulation of the nano-additivated phase change material in lightweight aggregates is presented. Encapsulation efficiencies of 30–40% are achieved. Phase change behavior is consistent across cycles. Cu nanoparticles provide nucleation points for phase change and increase the rate of progression of phase change fronts due to the enhancement in the effective thermal conductivity of n-octadecane. The effective thermal conductivity of the composites remains like that of regular lightweight aggregates and can still fulfil thermal insulation requirements. The thermal response of no-fines concrete blocks prepared with these new aggregates is also studied. Under artificial sunlight, with a standard 1000 W·m−2 irradiance and AM1.5G filter, concrete samples with the epoxy-coated aggregate-encapsulated n-octadecane-based dispersion of Cu nanoparticles (with a phase change material content below 8% of the total concrete mass) can effectively maintain a significant 5 °C difference between irradiated and non-irradiated sides of the block for ca. 30 min. [ABSTRACT FROM AUTHOR]

It is most effective to reduce floor impact noise as close to the sound source as possible. In apartments, there are multiple layers in the floor system, from floor finishing to the structural concrete slab. Apart from the floor finishing, mortar lies at the top layer of the floor system, followed by autoclaved lightweight concrete, insulation, and the concrete slab. The present study aims to identify the reduction characteristics of light and heavy floor impact noises by changing the glass transition temperature of an SBR (styrene–butadiene rubber) latex mortar. To achieve this, structural tests were undertaken to find the appropriate mix proportions of SBR latex in the mortar, meeting the glass transition temperature based on the physical test results regarding the latex mortar. As seen in the study method and process, because this study aimed to both increase and decrease the strength compared to general mortar, a 7% mixture ratio of Tg 4 °C SBR latex was decided upon for the strength increase, while a 5% mixture ratio of Tg −16 °C SBR latex was chosen for the strength reduction. A mock-up specimen was created using the SBR latex-modified mortar according to the identified mix proportions, and the characteristics of light- and heavy-weight floor impact noises of the SBR latex-modified mortar were then examined. Comprehensive analysis of the reduction performance of the floor impact noise revealed that the Tg −16 °C SBR latex-mixed mortar showed a reduction effect of about 2–5 dB for light-weight impact noise and about 7–10 dB for heavy-weight impact noise. [ABSTRACT FROM AUTHOR]

In today's environment, where energy is desired to be used more efficiently, it has been understood that the interest in the use of lightweight concrete with superior performance in terms of thermal insulation properties has increased. On the other hand, it has been stated that construction waste increases rapidly, especially after severe earthquakes. In this context, encouraging the use of recycled concrete waste and efficient disposal of construction and demolition waste is of great importance for the European Green Deal. It is also known that pollutants such as COx and NOx stick to facades over time, causing environmental pollution and visual deterioration. It has been reported that materials with photocatalytic properties are used in lightweight concrete facade elements to prevent such problems. This study examines the effect of using recycled concrete aggregates on the thermal properties of self-cleaning lightweight concrete mixtures (SCLWC). For this purpose, an SCLWC containing 1% TiO2 and 100% pumice aggregate was prepared. By replacing pumice aggregate with recycled concrete aggregate at the rates of 15%, 25%, 35%, 45% and 50%, four different SCLWCs with self-cleaning properties were produced. High-temperature resistance, thermal conductivity performance, microstructure analysis and photocatalytic properties of the produced mixtures were examined. It has been understood that the unit volume weight loss of SCLWC mixtures exposed to high temperatures generally decreases due to the increase in the recycled concrete-aggregate substitution rate. However, it was determined that the loss of compressive strength increased with the increase in the amount of recycled concrete-aggregate replacement. Additionally, it was determined that the thermal-conductivity coefficient values of the mixtures decreased with the use of pumice. After SCLWC mixtures were exposed to 900 °C, small round-shaped crystals formed instead of C–S–H crystals. [ABSTRACT FROM AUTHOR]

The meso‐structure of pervious concrete significantly influences its overall performance. Accurately identifying the meso‐structure of pervious concrete is imperative for optimizing the design of pervious concrete, considering its mechanical properties and functionality. Therefore, to address the difficulty of recognizing the meso‐structures of pervious concrete, a method utilizing deep learning image semantic segmentation techniques is proposed in this study. First, based on the classical deep learning model, three models, namely, Res‐UNet, ED‐SegNet, and G‐ENet, are proposed for recognizing pervious concrete meso‐structure using deep learning image semantic segmentation techniques. These models introduce a residual module, a hybrid loss function, and a differential recognition branching structure to enhance the ability to recognize detailed information within pervious concrete meso‐structure and small targets. Second, the respective recognition performances of these methods on the meso‐structure of pervious concrete were thoroughly analyzed by experiment. The results indicate that the proposed three recognition methods for recognizing the meso‐structure of permeable concrete outperform conventional techniques not only in terms of efficiency but also in recognition accuracy and the ability to distinguish and identify aggregates, pores, and cement binders. In terms of comprehensive recognition effectiveness, the Res‐UNet model outperforms, followed by ED‐SegNet and G‐ENet. Furthermore, the computational efficiency of these three recognition methods meets the requirements of engineering applications. [ABSTRACT FROM AUTHOR]

Translation abstract A supermarket made of infra‐lightweight concrete – Proof of stability for a fire wallInfra‐lightweight concrete (ILC) is a special form of lightweight concrete which, due to its low density, possesses improved thermal insulation properties in comparison to normal concrete. ILC facilitates the construction of monolithic, single‐layer building skins without any added thermal insulation or facade cladding. This way, the building components are effectively simplified in comparison to conventionally insulated concrete members and the recyclability is significantly improved. In addition to that, structural elements made of ILC have a reduced CO2 footprint in comparison to conventional composite elements of the building envelope. After 15 years of research and several completed construction projects in the housing and education sector, a commercial retail building has been realized. For this project, an individual approval for a firewall built out of ILC was obtained based on a fire test in combination with a transfer concept based on calculations. This article demonstrates the transfer concept as well as a simplified structural analysis concept for the proof of stability developed for the special application of a firewall. [ABSTRACT FROM AUTHOR]

Residential bathroom drainage noise is a primary source of indoor noise that directly affects quality of life and physical and mental health. Therefore, based on the acoustic theory and the finite element simulation technology, this paper proposes a method to simulate the drainage noise characteristics and its impact range jointly using the flow and acoustic fields. The pressure at the pipe wall caused by the internal flow field of the bathroom drainage pipe is calculated by the Fluent software. Simulations are carried out with the Virtual Lab software to predict the drainage noise characteristics and spatial distribution and to analyse the influence of factors such as the door position, riser position, and the partition wall material on the noise distribution. The results show that drainage noise has prominent high-frequency characteristics, the position of the bathroom drainage pipes and doors affects the spatial noise distribution, and the sound insulation performance of a partition wall with ordinary fired bricks in the bathroom is slightly better than that of ordinary concrete bricks, lightweight aggregate concrete blocks or fly ash blocks. This paper provides a theoretical basis and practical reference for reducing the impact of residential drainage noise and creating a healthy and comfortable indoor acoustic environment. [ABSTRACT FROM AUTHOR]

Functionally Graded Concrete (FGC) allows for a significant reduction in the mass of concrete components while maintaining their structural and functional requirements and improving recycling capacity. This is achieved by inserting spherical mineral hollow bodies into the structure where no material is required. Within the scope of this work, the behavior of FGC slabs exposed to fire is investigated both experimentally and numerically and compared to a corresponding solid cross-section. Therefore, FGC specimens are placed in a test furnace and subjected to fire exposure for 90 min. The temperature distribution, bending load-bearing capacity, and spalling behavior are investigated. The results of the numerical simulation of the solid cross-section are in good agreement with the values provided in the building code. However, for the FGC cross-section, differences in temperature at characteristic measurement points between the experimental and numerical results are observed, presumably due to convection. The experimental results suggest that the bending load-bearing capacity of the investigated FGC cross-section could be potentially greater than that of a corresponding solid cross-section. Furthermore, as expected through analytical analysis, the fire tests confirm that no spalling of the FGC specimens occurred. [ABSTRACT FROM AUTHOR]

To investigate the shear performance of assembled bamboo scrimber (BS)-lightweight concrete (LC) connection systems, three groups of nine BS-LC shear connections were fabricated in this work using BS, LC, dowels, and grout. The experimental parameters included the dowel diameter and fabrication process (cast-in-place vs. assembly). Push-out tests were conducted on the specimens, and traditional linear variable displacement transducer (LVDT) measurements and the advanced digital image correlation (DIC) technique were employed to determine performance indicators such as the cross-section slip of composite members. Subsequently, the method for calculating the shear capacity of assembled BS-LC connection systems was theoretically analyzed. The research results showed that the load-slip curves measured by DIC were highly correlated with those measured by LVDT, thus, validating the reliability of the DIC data. According to the DIC data, the variations in slip of the shear connection over the interface height were further analyzed. An equation for calculating the shear capacity of dowel shear connectors was proposed based on theoretical analysis with comprehensive consideration of the experimental indicators such as the failure mode, load-slip curve, shear stiffness, and shear capacity of the specimens. The theoretical calculation values were in good agreement with the experimental results. [ABSTRACT FROM AUTHOR]

The creation of lightweight aggregate self-compacting concrete (LWA-SCC) is a challenging endeavor with substantial consequences for the construction sector. However, the absence of firmly established design suggestions and recommendations as well as the limited availability of design approaches pose a noteworthy obstacle. To accomplish the anticipated mechanical properties while minimizing production costs as well as preserving natural resources, a thorough comprehension and understanding of the optimal combination of binders and coarse aggregate content is required. This study examines the impact of several supplementary cementitious materials (SCMs) such as silica fume (SF) and metakaolin (MK) on the fundamental mechanical characteristics of ecofriendly LWA-SCC mixes prepared with 100% sintered fly ash aggregate (SFAA) as a replacement of natural coarse aggregates (NCAs). A total of nine LWA-SCC mixes were prepared including one base SCC mix. The base SCC mix (C-SFAA100) encompasses 100% ordinary portland cement (OPC) as the sole binder, and 100% natural fine aggregates (NFAs) along with 100% SFAA. The remaining eight mixes were further parted into two Series. Series I and Series II comprise SF and MK as a replacement for OPC by 7.5%, 10%, 12.5%, and 15%, respectively. The fundamental mechanical characteristics such as compressive strength, split tensile strength, direct shear, and elastic modulus were measured after several intervals. In addition, microstructural analyses were also executed to appraise the overall efficacy of LWA-SCC combinations. The results such as the compressive strength of the SCC mixes CSF15-SFAA100 and CMK15-SFAA100 increased by 11.3% and 18.5%, respectively, after a curing time of 90 days compared to the base SCC mix C-SFAA100 confirmed that the incorporation of SCMs into LWA-SCC mixtures improves their mechanical characteristics. [ABSTRACT FROM AUTHOR]

This article presents an experimental analysis on the use of carbon fiber reinforced polymer (CFRP) sheets to enhance the flexural performance of lightweight concrete slabs. The study found that repairing the slabs with CFRP sheets increased their load capacity and prevented crack propagation. However, the effectiveness of the rehabilitation decreased with increasing damage. The article also provides a list of references related to the behavior and performance of various types of concrete structures, which can be valuable for researchers and engineers in the field. [Extracted from the article]

The objective of the REALight project is the development of a thermal process to produce lightweight aggregates in pilot scale and the implantation of a method to recover gypsum. Beside construction and demolition waste, various industrial by‐products are studied as raw materials. The raw materials have so far been unused or used in applications with lower quality requirements. To prove the performance of the lightweight aggregates, their technical properties are tested and their use in different applications is studied, e.g., for lightweight mortars as well as lightweight concretes. [ABSTRACT FROM AUTHOR]

At high temperatures, concrete may exhibit adverse mechanical behavior that compromises the safety of structures. Thus, it is necessary to study and develop concrete that can obtain greater performance in situations of exposure to high temperatures. In this regard, the present study investigates the replacement of 25% of sand by expanded vermiculite in different types of concrete and its performance when subjected to room temperature and punctual temperatures, of little content in literature, such as 200°C, 400°C and 800°C. This study also innovates by proposing the evaluation of prototypes exposed to high temperatures exclusively according to the perspectives of Brazilian technical standards, without resorting to international guidelines. Thus, the consistencies of the mixtures were determined and analyzed, as well as physical and mechanical tests that were carried out with the produced concrete. Among the results found are: vermiculite reduces the workability of the concrete mixture; vermiculite is not recommended for high-performance concrete, as it can significantly reduce its mechanical properties; in general terms, concrete that has a design strength of 50 MPa benefits from replacing the fines aggregate with vermiculite. From 400°C of exposure, all of the concrete samples showed cracks. The spalling phenomenon was also noticed in some specimens. The developed concrete samples cannot be characterized as lightweight concrete according to Brazilian standards, but o can be recommended as structural concrete given that their apparent specific mass is greater than 2000 kg/m³. [ABSTRACT FROM AUTHOR]

Given the widespread use of lightweight composite wall panels in building structures, it is crucial to comprehend their seismic performance. This paper proposes a new lightweight concrete composite exterior wallboard (LCEW) featuring truss-type thermal barrier connectors (TBCs). Through the proposed static test, the damage morphology and hysteresis curve of the specimen are obtained; the hysteresis characteristics, skeleton curve, stiffness degradation, etc., are investigated; and the damage modes are summarized. The results demonstrate that the steel frame structure can effectively adapt to the use of LCEW, resulting in an approximately 20% increase in the frame structure's bearing capacity. Second, the wall panels with a uniform transverse arrangement of TBCs could not perform as well, as they could only delay the crack opening. To give full play to its effect, it should be combined with the direction of the main tensile zone of the wall panels. Meanwhile, the sliding gusset connections effectively released the frame action at the system level. [ABSTRACT FROM AUTHOR]

Rehabilitating water-damaged structures in buildings results in increased material extraction and energy use, and, consequently, a higher carbon footprint of the housing industry. Despite its prevalence, quantifying the carbon footprint caused by water damage or flooding has not gained much attention. Thus, this study investigated the quantitative carbon footprint associated with rehabilitating flooding in a detached house caused by torrential rain. Three different construction methods of the house were looked at; a timber frame construction, a masonry variant made by concrete blocks of Lightweight Expanded Clay Aggregate (LECA), and an alternative with exterior walls composed of concrete-moulded Expanded Polystyrene (EPS) foam boards. A life-cycle assessment according to NS 3720 was used to investigate the carbon footprint (CO2eq.) of typical flooding in a detached building. Rehabilitating the flooding in a house with concrete-moulded boards resulted in a lower carbon footprint (2.45 × 103 CO2eq.) than rehabilitating the same flooding in a house with LECA masonry (7.56 × 103 CO2eq.) and timber frames (2.49 × 103 CO2eq.). However, the timber-frame house had the lowest total carbon footprint (2.95 × 104 CO2eq.) owing to their original low footprint. This study found that flooding significantly contributed to the carbon footprint of buildings and, therefore, the topic should be given attention when choosing a construction method and moisture safety strategy. [ABSTRACT FROM AUTHOR]

Mortar that is typically employed for interior or exterior coatings can be characterised using laboratory-prepared specimens according to specific test standards; however, its performance undergoes changes following application on substrates. When selecting mortar, it is vital to anticipate its in-service behaviour after its application on substrates to make the most informed choice. Most of the research work carried out to date analyses the characteristics of mortar in laboratory specimens. Some studies analyse these characteristics after its application to support, but very few exist that compare both behaviours. With this objective in mind, this research determined the properties of mortar when cured within laboratory moulds and assessed the behaviour of the same mortar after application on diverse substrate types. This study specifically evaluated the behaviour of a pre-dosed hydraulic lime mortar when applied on concrete blocks, lightweight concrete blocks, concrete slabs, hollow ceramic bricks, and solid ceramic bricks. Later, this behaviour was compared to the same type of mortar hardened in laboratory moulds and the same type of mortar applied on substrates and subjected to accelerated ageing. Moreover, data from previous experimental work were used to compare the behaviour of the pre-dosed hydraulic lime mortar with that of pre-dosed cement mortar when applied on similar substrates. The research drew upon a comprehensive characterisation of the physical and mechanical parameters of mortar, revealing that the performance of these types of mortar undergoes significant changes after application on substrates under in-service conditions, mainly when applied on more porous substrates. It was concluded that the application of mortar to substrates increased bulk density, decreased open porosity, enhanced compressive strength, and resulted in faster capillary absorption. For mortars subjected to accelerated ageing, a notable reduction in water vapour permeability was observed, which was attributed to changes in the pore profile. [ABSTRACT FROM AUTHOR]