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AbstractAs the global population has continued to grow, the costs and environmental issues associated with traditional construction materials like cement and river sand have become increasingly problematic. This study explores the innovative enhancement of early-age mechanical properties of 3D-printable mortar through the incorporation of Styrene-Butadiene Rubber (SBR) latex and kaolin. Various sands (Lawrencepur, Chenab, and Ravi) were tested at 120 min for compressive stress, direct shear strength, Young’s Modulus, and Shear Modulus. Lawrencepur Sand exhibited the highest compressive stress (206.75 kPa) and shear strength (74.60 kPa), followed by Chenab Sand and Ravi Sand. Young’s Modulus values were highest in Lawrencepur Sand (7.93 MPa), indicating superior stiffness, while Shear Modulus was highest in Chenab Sand (3.79 MPa). Ravi Sand, despite lower mechanical strengths, was found optimal for printable mortar due to its fine particle size and desirable texture. The incorporation of SBR latex and kaolin resulted in reduced maximum deflection and enhanced load-bearing capacity over time, with Lawrencepur Sand containing 99.64% sand particles and minimal silt bearing the ultimate load effectively. This study highlights the potential of SBR latex and kaolin in improving the early-age mechanical properties and suitability of sands for 3D-printable mortar, providing a balance between mechanical performance and printability. [ABSTRACT FROM AUTHOR]

AbstractThe insulation and noise and vibration damping characteristics of complex systems used by humans, such as automobiles, airplanes and ships are becoming increasingly important from the early design stages to ensure an adequate level of comfort. Especially in the naval fields, the design of insulation plans is crucial to prevent the propagation of noise and vibrations on board of megayachts. Since it is quite complex to identify and correctly model the sources due to their deterministic and random nature, during the early design stage, the focus is on insulation rather than reducing the acoustic levels of the sources themselves. In this article, a method for analyzing sea trials on a superyacht will be proposed with the aim of analyzing how much the insulation materials can limit the levels of vibrational energy on board during the path between sources and receivers. A new a descriptor based on harmonic transmission energy through the structure is proposed for path insertion loss experimental identification. In particular, by using spectral analyses and synchronous averaging of sound levels in various areas of the superyacht, it will be possible to study the vibroacoustic insulation of structural materials and their damping coefficient. [ABSTRACT FROM AUTHOR]

The paper gives a directive toward assessment of resilience of building designed to comply the nearly zero energy standard in the current conditions and also points out the gap in the existing approach for evaluating the effect that the climate changes could have on building material behavior and systems degradation. A method is introduced for evaluating how the variation of energy need and in-situ production can modify the energy balance under the representative concentration pathway of the intermediate (RCP 4.5) and the worst emissions scenario (RCP 8.5). The results for a case study indicate that under RCP 4.5 scenario, the polyethylene foam insulation has the higher increment of heating demand (+ 9.8%) instead the cooling demand decreases by −4.2% (RCP 8.5) and −4.6% (RCP 4.5). The innovative materials are less affected (<1%) by temperature variations. On the other hand, the PV system degradation causes the reduction of in-situ production from −6.9% (RCP 8.5) and −8.0% (RCP 4.5). However, the analysis of the hourly balance suggests that the building resilience would be not compromised. Indeed, by evaluating the ratio between the self-consumption and the total request, it increases compared to the current conditions of around 2%. [ABSTRACT FROM AUTHOR]

In the frame of the Venezia2021 project the private 'Byzantine house' designed by Giuseppe Torres in 1905 was chosen as the emblematic architectural site which marks Venice's transition towards modernity, requiring study of its conservation in the lagoon environment of the city of Venice. In conjunction with the definition of a specific Path of Knowledge of the ground floor, a series of stone and lithoid materials as well as their related deterioration products from the interior rooms were sampled for analysis. The investigations covered a wide range of materials (plasters, mortars, natural and artificial stones, bricks, glass and finishings). They were carried out by means of a multi-analytical approach comprising SEM-EDX and optical microscopy; XRPD; XRF, ion chromatography; and Raman and infrared (FTIR) spectroscopies. The stones identified are linked to the Venetian architectural tradition (Euganean trachyte and Istrian stone). The sands in the mortars are mainly of regional origin and the glass is compatible with traditional Venetian (Murano) recipes. Of particular interest is the presence of an intonachino charged with ground fluorite. The deterioration products are linked to the extensive and intense phenomenon of capillary rising damp and efflorescence deposition induced by the lagoon environment. [ABSTRACT FROM AUTHOR]

Algerian Mzab traditional houses, using passive techniques since the eleventh century (from 1012 to 1882), have seen recent modifications. Analysis of 612 questionnaires and interviews with Mzab residents reveals 81.2% of these houses have been modified. Modifications include adding floors, thinning walls, and replacing lime with cement, driven by the need for space, ventilation, and modernisation. However, such modifications often increase energy consumption, with residents requiring more heating in winter and air conditioning in summer. This reliance on fossil fuels exacerbates regional climate insecurity. Planting roof terraces and using high-insulation building materials can reduce energy consumption in modified Mzab houses. [ABSTRACT FROM AUTHOR]

Compatibility tests are carried out on Ni-based Hastelloy alloys and stainless steel under the influence of the molten chloride salt NaCl-CaCl2-CeCl3 to investigate the corrosion behavior of molten salts with structural materials. Weight change measurements before and after the reaction tests show that the Hastelloy alloys have better corrosion resistance than stainless steel. The effects of molten salt purification on the corrosion behavior in the Hastelloy alloys are explored. The composition of the reacting phases is identified from transmission electron microscopy analysis and the corrosion mode is homogeneous corrosion with Cr and Fe diffusion, followed by Mo and Ni elution. [ABSTRACT FROM AUTHOR]

This study examined the encapsulation of Bacillus sphaericus LMG 22257 spores in biopolymeric microcapsules (MCs) for use in cement mortar, with a focus on enhancing self-healing properties. Biopolymers, including alginate (ALG), chitosan (CTS), carboxymethyl cellulose (CMC), and ALG/CMC blends at various ratios, were employed to fabricate the MCs through ionotropic gelation and freeze–drying. The physicochemical properties of MCs, including size, morphology, and swelling behavior under simulated concrete conditions, were assessed. Among these, ALG/CMC-MCs exhibited superior characteristics and demonstrated the highest urea hydrolysis activity when incorporated into the mortar, indicating optimal spore protection. Despite an initial decrease in compressive strength, the ALG/CMC blend with an ALG:CMC mass ratio of 6:4 achieved a crack healing efficiency of 96.7% over 28 days under cyclic wet-dry conditions. These findings highlight the potential of biopolymer encapsulation for embedding functional microorganisms in construction materials, contributing to a more durable and sustainable infrastructure. [ABSTRACT FROM AUTHOR]

Research on the sustainable production of building materials has been increasing from time to time. The construction industry is one of the sectors that leads to the depletion of significant amounts of nonrenewable resources, such as minerals. The ecosystem is deteriorated, and carbon dioxide (CO2) emissions are enormous in the environment due to the use of fossil fuel-based materials. The purpose of this paper is to review the use of plant fibers (hereafter NF) for reinforcement in cementitious concrete. Concrete, plant fibers, their chemical nature, and characteristics are highlighted in an overview. The most important issues in NF-concrete compatibility were discussed, which could provide research opportunities. Modification of NFs and the cement matrix are examined as methods for improving compatibility and degradation. Moreover, the properties and longevity of cementitious materials that are reinforced with natural fibers are also examined. Finally, the review emphasizes the significant research gaps and future research prospects identified in the reviewed papers. [ABSTRACT FROM AUTHOR]

Nanomaterials have garnered significant attention in recent years for their potential to enhance the mechanical properties of cementitious construction materials, particularly in high-strength concrete applications. This review aims to explore the effects of various types of nanomaterials on the mechanical properties of concrete materials. Current developments in the synthesis, characterization, and use of nanomaterials in the field of cementitious materials are thoroughly examined in this review. The incorporation of various nanomaterials such as nano-silica, nano-titania, carbon nanotubes, nano-clay, and nano-alumina can significantly enhance the mechanical properties of cementitious construction materials, particularly in high-strength concrete applications. These nanomaterials contribute to denser microstructures, improved hydration products, and enhanced interfacial bonding within the cement matrix, ultimately leading to superior mechanical performance. However, proper dispersion, dosage, and compatibility considerations are essential to realize the full potential of nanomaterials in cementitious materials. The optimum % of NS in cement was reported to be between 1 and 8%, whereas the optimum % of graphene oxide (GO) in cement was reported to be only between 0.05 and 0.5%, imparting high strength characteristics to concrete. The findings of the study promote the use of nanoparticles in cement concrete to enhance the strength of high-rise concrete buildings. The results of various studies are compared, and some significant recommendations are also made. Furthermore, this research underscores the practical applications of nanocomposite-based concrete materials while acknowledging their limitations and opportunities. [ABSTRACT FROM AUTHOR]

AbstractPopulation growth and urban expansion have increased impervious surfaces, leading to environmental issues such as stormwater runoff and groundwater depletion. Traditional concrete, while durable, contributes to these problems. There is a need for sustainable construction materials that can address environmental challenges and reduce the consumption of natural resources. Pervious concrete, enhanced with recycled aggregates (RCA) and supplementary cementitious materials (SCMs) like metakaolin (MK) present a potential solution. This study aims to improve the mechanical and durability properties of pervious concrete by incorporating RCA and MK, assessing their effects on workability, density, porosity, permeability, compressive strength and flexural strength. The incorporation of RCA resulted in increased aggregate porosity compared to natural aggregates. Workability was assessed using the slump test, density was measured, and porosity and permeability were evaluated. The results showed that incorporation of RCA generally decreased workability, density and strength, while the addition of MK improved these properties by refining the microstructure. Specifically, mixes with 10% MK demonstrated better performance in terms of increased compressive and flexural strengths, improved density and reduced porosity. The ANN model showed high accuracy in predicting compressive and flexural strengths. The study concludes that RCA and MK can enhance the mechanical and durability properties of pervious concrete. [ABSTRACT FROM AUTHOR]

AbstractConcrete structures have high massive building materials than steel structures and possess very low thermal conductivity and high specific heat capacity. However, an efficient approach to reducing high production cost and structural weight of concrete elements without impacting their strength evolve as a growing necessity that leads to innovation in the Light weight concrete (LWC) fields such as aerated concrete and foamed concrete. Those large bubbles seem highly likely to get a break, move upwards through buoyancy and may get lost, while concrete has been mixed, transported, placed and vibrated. Hence to prevent increased bubble spacing, and air loss and to increase concrete durability, a sort of micron-sized air-cells could be generated in aerosol form, by passing out compressed air to dense form generating surfactants. Therefore to circumvent certain drawbacks of conventional LWC, the study delineated to bring out an innovative air-cell impregnated concrete (AIC) material, with homogenous mixing of cement, sand, water and uniformly distributed micron-sized air-cells wherein course-aggregates were replaced with air-cells. This uniform air-cell distribution creates durable concrete with unique feature characteristics since the micron-sized air-cells will be stable and does not collapse. The suitable surfactant towards contributing the strength and durability of proposed AIC structure are assessed, based on results. [ABSTRACT FROM AUTHOR]

Residential buildings consume approximately 36% of total electricity consumption in Cyprus and this is expected to continue increasing in the coming years. This study explores the potential for energy savings in residential buildings in Cyprus through optimising building envelopes and insulation materials. Using building information modelling and energy modelling software, the study analyses 120 combinations of building envelopes and eight insulation materials, identifying an optimal combination of wall, roof, and flooring materials that could result in 32% energy load reductions and 27% lower life-cycle costs compared to the median scenario. High-density rock wool insulation on roofs and double-glazed windows were also found to offer both monetary and energy performance benefits. A sensitivity analysis revealed that the current high energy prices could provide greater economic incentives to adopt these optimisation strategies. Optimising building materials in Cyprus could play a critical role in climate strategy while also offering significant economic benefits. [ABSTRACT FROM AUTHOR]

The use of alternative masonry units and technologies in traditional masonry work could reduce the life cycle energy of buildings. This study investigates the life cycle energy assessment of houses constructed using concrete blocks, eco-bricks and polymer bricks to evaluate the impacts of masonry units on the life cycle energy of buildings. Three bungalows of approximately 110 m2 each, having the same geometry but different types of wall materials, namely eco-bricks, polymer bricks, and concrete blocks, were used for the analysis. The study found embodied manufacturing energy of 0.346 MJ/kg for eco-bricks and 0.518 MJ/kg for polymer bricks. Approximately 85-86% of the total life cycle energy constitutes the operational phase energy. The polymer brick and eco-brick buildings had the least embodied construction energy of 14% of the total life cycle energy. The life cycle energy of concrete block buildings was 17.547 GJ/m2 at 50 years of service life. Buildings made of polymer bricks and eco-bricks had lower life cycle energy than the concrete block building. The study suggests a prudent selection of building materials by developers and construction professionals based on life cycle energy assessment to reduce the energy consumption of the building sector. Although the study focus is limited to eco-bricks, polymer bricks, and concrete blocks as masonry units in the Nigerian construction context, the method employed in the study is applicable to the energy analysis of other construction materials and geographical locations. [ABSTRACT FROM AUTHOR]

The incineration of municipal solid waste (MSW) produces byproducts known as MSW incineration (MSWI) ash. The reuse of MSWI ash as a construction material prevails in several areas of the world, namely Europe and Asia, however, reuse in the United States (US) lags due to regulatory requirements for disposal practices. Developing a recycling program for MSWI ash provides an alternative end-of-life disposal scenario for material currently landfilled and supplements the reliability of mining of natural aggregates. This study provides a programmatic review of the past decade of challenges and opportunities a local government in the US has experienced to implement a recycling program for their MSWI bottom ash (BA) as a construction aggregate in road materials, such as hot mix asphalt, concrete pavement, and road base. The regulatory and practical challenges in the U.S. are presented, including meeting mechanical and environmental performance requirements (e.g., strength and leaching-to-groundwater). The novel approach to overcoming these challenges include blending MSWIBA from two facilities with common aggregates, creating suitable construction materials. Interfacing with local and state agencies, such as the Department of Environmental Protection and Transportation resulted in additional testing to establish the MSWIBA as a beneficial use material and obtain essential approvals for advancing reuse opportunities. This paper synthesizes available data regarding the challenges, opportunities, and implementation of this recycling program by reviewing the experiences of an MSWI facility in the US to provide fundamental guidance to those considering similar applications. Implications: The reuse of municipal solid waste incinerator bottom ash (MSWIBA) lags in the United States (US) due to regulatory limitations and lack of precedence. This manuscript details the steps of a local government in the US to establishing a novel recycling program for their MSWIBA, including performance evaluation, regulatory interfacing, and outreach. This critical review provides a comprehensive document containing appropriate considerations required to implement similar MSWIBA recycling programs in the US and offers lawmakers, policymakers, and MSWI operators knowledge regarding opportunities and challenges associated with pursuing this avenue. [ABSTRACT FROM AUTHOR]

Quarry fines are secondary materials that can be reused for road construction, commonly after improving their properties through stabilising. To better understand and characterise these recycled materials, we created an image-based, two-dimensional representation of the particles that compose the material. This computational representation enables (1) the quantification of the (area-based) gradation from images, (2) a detailed particle-by-particle characterisation and (3) potentially, random rearrangement of the particles into reconstructed specimens for further computational analyses. The images of cement-stabilised quarry fines were obtained using a scanning electron microscope. The particles were isolated and characterised using image processes and a computational approach (MATLAB code). The techniques and code presented herein can be applied as well to other granular-based materials. The MATLAB code and associated files are available as an open resource in GitHub (). [ABSTRACT FROM AUTHOR]

Parents boost STEM skills by scaffolding children's attention and discovery during play, but many need support doing so. Using human-centered design (HCD) methods, we created activity kits fostering parents' (a) involvement in and (b) valuing of parent-child play to promote preschoolers' STEM skills. Study 1 documents how HCD methods informed the design of guided activity kits. In initial home visits, we videorecorded six parent-child dyads playing with basic building materials. Play revealed minimal parental STEM scaffolding and talk. Collaborating with 18 families and drawing on prior research, parent interviews, videotaped play sessions, and advisory-board members' expertise, the interdisciplinary research team designed and refined activity kit prototypes. Study 2 was a randomized field test comparing use and evaluation of final guided kits (n = 50) versus basic kits (n = 25) that contained identical building materials and challenges but omitted scaffolding guides. Both groups received kits by mail every other week for 10 weeks. Relative to parents given basic kits, parents given guided kits (a) reported significantly more sustained use of the kits across the 10 weeks, (b) felt more self-efficacy in fostering their child's STEM learning, and (c) judged that their child had achieved greater STEM-skill learning from program use. [ABSTRACT FROM AUTHOR]

AbstractThis study examines how the state categorises and governs the urban poor in the Philippines, implementing different housing policies for citizens who can pay regular prices and the urban poor who cannot. Slum dwellers who cannot afford land are categorised as “underprivileged and homeless citizens” and receive state protection. Meanwhile, those considered able to afford land are classified as “professional squatters” and are subject to imprisonment and/or fines. Since the 2000s, the state protection has been via market-driven policies, which have proven insufficient as local governments and private developers relocate slum dwellers for high-end housing projects that force these dwellers to purchase relatively expensive socialised housing in suburbs with inadequate infrastructure or livelihood opportunities. This article reviews the inadequacy of state protection by examining the role of courts that might protect slum dwellers from the state’s market-driven policies. This analysis indicates that, based on the building materials of houses, the courts are likely to define slum dwellers as professional squatters. This is not necessarily an accurate reflection of their living standard, compared to income. Underprivileged and homeless citizens are easily relocated under market-driven policies, and if they resist in court, they are likely to be treated as professional squatters. [ABSTRACT FROM AUTHOR]

AbstractLimestone calcined clay cement (LC3) is identified as an auspicious solution to the exhaustion of natural resources intended for use as construction materials. This is seen as a means of reducing both the carbon dioxide emissions and the environmental effects of energy-intensive cement manufacture. Three novel types of LC3 cements and mortar varieties were synthesized, characterized, and their potential use was assessed. Microstructural investigations were performed using experimental techniques such as XRD, XRF, FTIR, SEM, setting time, and thermal analysis. Physical and mechanical properties were also evaluated at 2, 7, and 28 d. The results showed that hydrated phases alongside the original ones were encountered. SEM micrographs exhibited some features belonging to the already detected phases. The mechanical strength of the manufactured LC3 samples (up to 35 MPa) was quite promising compared to that of commercial cements. From the above, it could be stated that the used materials might be a good substitute for clinker in the manufacture of LC3 cements. LC3-50 and LC3-52 may both be used in favor of CPJ35 and CPJ45, respectively. [ABSTRACT FROM AUTHOR]

AbstractRapid urbanization, poverty and socio-economic inequalities are causes of the backlog of informal settlements in South Africa, as dwellers cannot access formal housing schemes. Such unplanned settlements often need more basic services, social facilities and adequate housing. Nevertheless, informal settlements are core parts of the urban form rather than places for eradication. This article examines self-building and community-led upgrading practices in three case studies of partially and non-serviced informal settlements in Durban. It adopts action research participatory methods to coproduce knowledge and map various perspectives around community-led housing upgrading, building materials and construction skills in an effort to enhance community resilience and self-reliance. The findings reveal the key drivers and challenges associated with self-building, informal procurement and overall project management of the housing process. Successful grassroots practices demonstrate community ownership and dweller control beyond the physical upgrading per se. The lessons learned call for inclusive, participatory, and incremental approaches for effective community organization, self-reliance, social capital and livelihood development. [ABSTRACT FROM AUTHOR]

Glutinous rice mortar is a traditional lime-based building material which was first used in China during the Southern Song Dynasty (1127-1279 CE) according to ancient Chinese documents. The Tieguai Tomb, dating back to the late Northern Song Dynasty (960-1127 CE) in Nanling, Southern China, was built by using mortar for its tomb chamber, making it the earliest mortar tomb found in China to date. In this study, X-ray fluorescence spectroscopy (XRF), X-ray diffraction (XRD), thin-section petrography, Fourier transform infrared spectroscopy (FTIR), and starch grain analyses were conducted to comprehensively investigate the manufacturing techniques of the mortar from the Tieguai tomb. The results show that the mortar is a type of organic–inorganic mixed material made of glutinous rice pulp, lime, clay, and fine sand. This finding indicates that glutinous rice mortar had already been used as a building material as early as the late Northern Song Dynasty, which is the earliest use record for this material in China. This study also provides direct scientific evidence for exploring the origin of glutinous rice mortar and is of great importance for reconstructing the history of Chinese traditional building materials and architectural techniques. [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]

As a result of firing pulverized coal in thermal power plants, enormous amounts of fly ash (FA) are produced as industrial waste. The release into the atmosphere and storage of this industrial waste remains one of the major environmental problems that threaten human health by contributing to air, water, and soil pollution. The recovery and reuse of FA in the construction industry is the only economic solution to the existing problem. In this study, the potential radiological risk caused by the usage of FA in concrete and cement production as a main component and its storage in landfill sites was evaluated for people and works by estimating radiological parameters (activity concentration and alpha index, annual effective doses, and the corresponding excess lifetime cancer risks) based on activity concentrations of terrestrial radionuclides in FA. Also, the radiological risk to the workers working in the FA landfill site was evaluated using the Residual Radioactivity Onsite 7.2 code. The average activity concentrations of terrestrial radionuclides in FA samples from the Tunçbilek lignite coal-fired thermal power plant at Kütahya province of Turkey were measured as 417, 156 and 454 Bq kg−1 for 226Ra, 232Th and 40K, respectively. When using up to 35% by mass of FA in cement and concrete, the average values of the radiological parameters revealed that they were within the recommended safety limits. However, code estimations showed that a regular worker in FA storage would be exposed to a total effective dose rate greater than 3 mSv y−1. [ABSTRACT FROM AUTHOR]

High-performance building envelope materials, components and systems have been developed to achieve reduction in energy demand and meanwhile maintaining a satisfactory indoor environmental quality. The performance of building envelopes is generally assessed through numerical and experimental methods. Experimental work conducted with outdoor testbeds provides live data under real weather conditions, and therefore become an effective approach to evaluating the performance façade technologies. This paper reviewed 82 outdoor testbeds employed in studies on performance of building envelopes. They are categorized according to scale and form. Representatives in each category are discussed in details, and the main features are compared and summarized systematically. The functions of testbeds are analyzed according to the dedicated experimental purposes. Different construction materials and structures are also compared. On this basis, recommendations are made for future design, construction and application of outdoor testbeds. [ABSTRACT FROM AUTHOR]

With the high incidence of chronic diseases, precise nutrition is a safe and efficient nutritional intervention method to improve human health. Food functional ingredients are an important material base for precision nutrition, which have been researched for their application in preventing diseases and improving health. However, their poor solubility, stability, and bad absorption largely limit their effect on nutritional intervention. The establishment of a stable targeted delivery system is helpful to enhance their bioavailability, realize the controlled release of functional ingredients at the targeted action sites in vivo, and provide nutritional intervention approaches and methods for precise nutrition. In this review, we summarized recent studies about the types of targeted delivery systems for the delivery of functional ingredients and their digestion fate in the gastrointestinal tract, including emulsion-based delivery systems and polymer-based delivery systems. The building materials, structure, size and charge of the particles in these delivery systems were manipulated to fabricate targeted carriers. Finally, the targeted delivery systems for food functional ingredients have gained some achievements in nutritional intervention for inflammatory bowel disease (IBD), liver disease, obesity, and cancer. These findings will help in designing fine targeted delivery systems, and achieving precise nutritional intervention for food functional ingredients on human health. [ABSTRACT FROM AUTHOR]

Silica aerogels (SA) have exceptional thermal insulation capabilities, however, their superhydrophobic nature hinders the formation of a uniform composite when combined with cement slurry. To address this issue, an aqueous solution was employed to disperse SA particles using sodium dodecyl sulfate (SDS). Subsequently, the dispersed micelles were coated with polydopamine (PDA) through in situ polymerization. This approach effectively enhanced the dispersion of SA in cement slurry and improved its connection force with the cement hydration products, thereby mitigating the adverse effects of aggregated SA on the mechanical properties of the cement composite. The successful PDA coating led to the formation of smaller aggregated micelles, resulting in a 30% improvement in compressive strength of cement composites containing modified SA compared to those using unmodified SA, while maintaining the desired thermal conductivity properties. With a strategic increase in the quantity of modified SA, a remarkable thermal conductivity of 0.1351 W/m·K was achieved without significantly compromising the compressive strength, which reached about 13.94 MPa. This enhanced compressive strength surpassed that of conventional thermal insulation materials like expanded polystyrene (EPS) and foam concrete. Consequently, this novel technique has the potential to markedly enhance the thermal insulation of cement composites without excessively impacting their compressive strength, thus contributing to the development of green insulation and energy-saving building materials. [ABSTRACT FROM AUTHOR]

Despite their undeniable potential for promoting sustainability in construction materials, the characteristics of recycled aggregates (RCA), seawater, and sea sand may vary significantly, thereby affecting their use in structural concrete. This study exploits these materials to investigate their performance in producing sustainable concrete and establishing its mechanical and fracture behavior. The so produced material, referred to as seawater sea sand recycled aggregate concrete (SSRAC) could lend a hand in widening the usage of RCA and sea sand in a variety of applications where the use of ever-depleting natural materials as concrete constituents becomes an issue. Consequently, the variables of the study include the type of water (fresh versus seawater), type of coarse aggregate (RCA versus natural coarse aggregate, NCA), and the type of fine aggregate (dune sand versus sea sand). For each water type, three concrete mixtures are produced using NCA-dune sand, RCA-dune sand, and RCA-sea sand combinations. Analyses of the mechanical characteristics of the concrete, including compressive strength, flexural strength, modulus of elasticity, and fracture toughness, were conducted based on experimental tests. X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) analyses were also conducted on the designed specimens to investigate their microstructure. In terms of fracture characteristics, the use of seawater resulted in improvement in the fracture toughness. The use of recycled aggregate along with seawater resulted in improved compressive strength. However, natural aggregate concrete (NAC) showed higher flexural strengths than recycled aggregate concrete (RAC). The results also revealed that the addition of sea sand had a detrimental impact on all mechanical characteristics. Thus, optimizing the concrete composition in which the investigated materials partially replace the conventional concrete constituents is required in order to consider alternative constituents to generate sustainable concrete for practical applications. [ABSTRACT FROM AUTHOR]

For thousands of years, mortar-based materials — including bedding mortars, plaster floors, internal wall plasters, external wall renders and stuccos, and concrete — have been key construction materials in many cultures throughout the world. This paper gives an overview and examples of the use and development of mortar-based materials in cultures across the Middle East, Europe, Asia, and Mesoamerica, prior to the development of hydraulic cements in the late 18th and early 19th centuries. [ABSTRACT FROM AUTHOR]

Natural radionuclide activity concentrations were measured in ceramic, gypsum, and brick samples from manufacturers, dealers, and construction sites in and around Addis Ababa, Ethiopia, using an HPGe detector. The study's main aim is to assess the activity concentration of building materials and their health impacts. Average activity concentrations (Bq kg−1) for 226Ra in ceramic, gypsum, and brick samples were obtained as 81 ± 1, 1.34 ± 0.17, and 39 ± 1, respectively. In ceramic, gypsum, and brick, concentrations of 232Th were obtained as 166 ± 4, 0.68 ± 0.18, and 103 ± 3, respectively, while concentrations of 40K were found to be 755 ± 16,15 ± 1, and 921 ± 24, respectively. Some of the materials that were tested, especially the ceramic samples, had slightly higher concentrations of radionuclides in comparison to other analysed samples. In all samples except ceramic, Raeq was < 370 Bq kg−1, which is the recommended limiting dose for bulk medium. Furthermore, the corresponding radiological parameters, such as absorbed dose, annual effective dose equivalent, excess lifetime cancer risk (ELCR), internal (Hin) and external (Hex) hazard indexes, gamma index (Iγ), and alpha index (Iα) were determined. The ELCR average values in this study are slightly higher than the global average, and the indoor and outdoor absorbed dose rates are greater than the limiting criteria of 84 and 59 n Gy h−1, respectively. Therefore, it is important to assess the potential radiation risk of ceramic samples, which should be used in a controlled manner to reduce gamma exposure to residents. Finally, the computed data could be used as a baseline to assess any future radiation exposure from construction materials. [ABSTRACT FROM AUTHOR]

The core part of this study is comprised of using the soft computational approach for analyzing the thermoelastic reaction of a concrete sandwich beam with transversely-graded composite face sheets as an advanced building material exposed to an axially-directed abrupt thermal load. First of all, the relations governing motion are extracted from the principles of three-dimensional elasticity theory. Besides, the time-variable relations of heat conduction are derived based on the Fourier heat conduction cooperating with Lord–Shulman theorem of heat transfer. Continuity of the displacements and stresses on the core's borders interacting with face sheets is taken into consideration. To find the solution of the time-variable governing equations of motion, the Laplace transform in conjunction with the differential quadrature approach (DQA) is utilized. Transforming the system's reaction from Laplace space to the time domain is done through an extended expression of Dubner and Abate's approach. To speed up the computational process, a soft computational approach on the bases of optimizing a deep neural network with a shuffled frog leaping algorithm (SFLA) is implemented. Efficiency of the applied methods is inspected though comparing their outcomes with those obtained from the existing literature for different boundary conditions. [ABSTRACT FROM AUTHOR]

This study investigates the plastic deformation-induced fcc → hcp → bcc phase transition within nanograins in an ultra-strong gradient nanostructured surface layer on Fe45Mn35Cr10Co10 compositionally complex alloy (CCA), subjected to a single point cubic boron nitride turning process. High-resolution transmission electron microscope observations reveal a novel atomic movement mechanism of this transition following a unique Nishiyama-Wassermann orientation relationship. Unlike the previously validated Bogers-Burgers-Olson-Cohen model, which follows different orientation relationships and relies on two shear components, this study demonstrates that the phase transition in this CCA is cooperatively completed by two sets of half-partial dislocation dipoles and associated atom shuffling. Statement of Novelty A novel atomic mechanism of fcc → hcp → bcc phase transition, cooperatively completed by two sets of partial dislocation dipoles and atomic shuffling, provides potential implications for advanced structural materials. [ABSTRACT FROM AUTHOR]

This study presents a critical historical review of one century of methods, results and regulations concerned with permeability testing of concrete and other stone building materials, keeping under a magnifying glass the triad of factors invasiveness-reliability-insight with the objective of scouting the feasibility of a near-zero-invasiveness practice, alternative to some recent standards. This practice is herein proposed for integrating actions of surveying, sampling and watertightness testing of a concrete cover object of a life cycle appraisal in a reinforced concrete structure for possible replacement from a perspective of sustainability and evaluated on a historical documental basis. Two main conclusions of this study are: the feasibility, on a historical documental basis, of cutting specimens for permeability testing from thin regions of concrete cover, and the great importance for the decision-maker to have access to sufficient diagnostic data suitable to let her/him discern the self-sealing or self-unsealing nature of the concretes under investigation. [ABSTRACT FROM AUTHOR]

Non-phthalate plasticizers are being increasingly used in commercial and consumer products, to replace phthalates. Among major non-phthalate plasticizer groups, we chose five alternative plasticizers of DEHA, DINCH, DEHTP, ATBC, and TOTM, and conducted a systematic literature review for current knowledge on their use and occurrences in major sources, and their exposure and endocrine outcomes in humans. Relevant articles published between January 2000 and December 2022 were identified from PubMed and Scopus search and analyzed. For occurrence, biomonitoring, and endocrine-related outcomes, 79, 73, and 14 studies were finally identified, respectively. The alternative plasticizers were widely used in food packaging, children's products, hygiene products, medical devices, and construction materials, and frequently detected in indoor dust. Food packaging materials and children's products were major sources of direct exposure to humans. Human exposure to alternative plasticizers is reported mostly via biomonitoring of urine. Urinary levels of DEHTP and DINCH metabolites were higher among infants, children, and pregnant women than in general adults. In humans, DEHTP, DINCH, or ATBC exposure were associated with sex hormone disruption and reproductive outcomes, but these associations varied by sex and age. This review showed that the use of and exposure to these alternative plasticizers have increased over time. Their potential health implications, especially among susceptible humans, warrant greater attention and further investigation. [ABSTRACT FROM AUTHOR]

Radon is a radioactive noble gas omnipresent in the environment, being part of the 238U and 232Th decay chains present in the Earth's crust. The gas can easily leak through the ground but also be present in natural construction materials and migrate into indoor places where it can be a carcinogen when inhaled. Studying the content and removal of indoor radon is crucial for the evaluation and mitigation of its radiological risks to public health. For more than 100 years, the removal by adsorption of the radon has been performed on activated charcoal. There is little progress in the field of radon adsorption at ambient conditions; the main progress is in the use of zeolite materials, having well-defined three-dimensional porous structures and radiation resistance. This study concerns a report on the state of the art of the application of zeolites in radon adsorption. Furthermore, an optimized approach for measuring the radon content in indoor environments and, consequently, its removal has been proposed. Adsorption systems based on zeolites have the potential to replace activated charcoal as a material of choice, allowing to facilitate the development of simple and compact radon adsorption systems. [ABSTRACT FROM AUTHOR]

The performance of reclamation cover systems could be affected by the colonization of plant roots, which may modify the hydrogeological properties of the construction materials. A four-year field investigation was conducted using six experimental cells with various soil layering designs over AMD-generating tailings reclaimed with an oxygen-barrier cover combined with an elevated water table. Both herbaceous and woody vegetation were installed on top of the cells to compare the influence on the properties of the cover material. Consecutive and undisturbed cores were collected from the cover's functional layer in 2020 and 2021, respectively. Root parameters, such as root length density, and hydrogeological properties were measured on the core samples to assess the possible relationships between the two categories of variables. Root observation trenches were also cut in each cell to better analyze the root density and occurrence profiles. Results showed that, within the four-year monitoring period of the study, both herbaceous and woody vegetation roots mostly colonized the top overburden layer of the cell (>86% visible roots) and barely occupied the functional layer of the reclamation cover (<10% visible roots). The observed maximum desorption rates for the functional layer were lower than the predicted values, which could be a short-term effect of the fine roots. No significant impact of roots on the main hydrogeological variables controlling the oxygen barrier efficiency were noted. At the end of the four-year study period, the hydrogeological behavior of the functional layer in all cells with/without vegetation/additional soil layers was found to be similar. [ABSTRACT FROM AUTHOR]

Airborne respirable crystalline silica (RCS) has been a widely recognized hazard in the United States for nearly 100 years, yet it continues to pose a risk to construction tradespersons, among others. RCS exposures vary widely depending on site conditions and tools and materials used. The proper use of engineering, administrative, and personal protective equipment (PPE) controls can effectively reduce exposure to RCS. Historically, others have reviewed available RCS exposure data among construction trades and reported that there were considerable data gaps and variability that needed to be addressed. This current assessment aimed to synthesize available peer-reviewed exposure studies to determine potential RCS exposures during the use of common construction materials and evaluate to what extent data gaps and variability persist. Twenty-eight studies were identified that reported RCS exposure during construction tasks. After conversion to the unit of µg/m3, reported measurements from samples collected for varying durations ranged from 6.0 to 75,500 µg/m3 for work with concrete, 80 to 4,240 µg/m3 for work with brick, <59 to 10,900 µg/m3 for work with mortar, 90 to 44,370 µg/m3 for work with engineered stone, and 70 to 380 µg/m3 for work with roof tile. To better facilitate pooling data across studies, future researchers should report their sample duration, clarify how time-weighted average (TWA) exposure data are calculated, report the silica content of the material being manipulated, and specify whether samples were collected while the task was performed in isolation or on a worksite where other silica-containing materials were also actively handled. When reporting results as respirable quartz, it is important to note whether any other polymorphic forms of silica were detected. It is ultimately the employer's responsibility to train employees and monitor and control RCS exposures on construction worksites. To do this effectively, it is important to have a clear understanding of the tasks, materials, and site conditions where intervention is most urgently needed. [ABSTRACT FROM AUTHOR]

AbstractThis study aims to evaluate the mechanical characteristics of Kenaf Textile Reinforced Concrete (KTRC) specimens to address the growing interest in sustainable construction materials. The research investigated various parameters, including modulus of rupture, total toughness, and toughness indices, while also exploring the impact of polypropylene (PP) chopped – fibre, the number of textile layers (3 and 5), and their arrangement (symmetric and asymmetric) on the mechanical properties of KTRC. The results demonstrated that Kenaf meshes could be used as natural and cost-effective reinforcement in TRC. Increasing the number of reinforcement layers significantly enhanced total energy absorption, and the combination of chopped fibre and Kenaf meshes contributed to maintaining the crack strength of the composites. The results of the three-layer specimens demonstrate that as the percentage of PP fibres increases from 0% to 0.5% and 1%, there is a noticeable increase in toughness compared to the reference samples. Specifically, the toughness of the samples increased by 978.6, 1381.1, and 1520.7, respectively. Eventually, the behavior of the specimens until the moment of complete rupture mostly depends on the number of layers in the thickness of the specimen. [ABSTRACT FROM AUTHOR]

On the 2nd runway of Shanghai Pudong International Airport, the field assessment was conducted for rigid pavement stabilization using cementitious grout. The support performance of underlying layers and voids beneath slabs were considered, and the deflection testing was performed before and after grouting. The performance of pre-treatment and post-treatment pavements, and effects of injecting depth and curing time on grouting treatment were statistically analyzed. Results indicated that the support performance of underlying layers along the wheelpath was gradually getting deteriorated and non-uniform during the service period, and the number of voids beneath slabs would also increase annually. The injecting depth at 10 cm under subbase layer was proposed for rigid pavements with the crushed stone subbase layer. Besides, the performance evaluation of cementitious grouting stabilization for rigid pavement was recommended after 60-day curing. Finally, results demonstrated that the objective of pavement stabilization for the 2nd runway was successfully achieved. [ABSTRACT FROM AUTHOR]

The interlayer bonding condition in asphalt pavement significantly affects pavement performance. This study employed machine learning techniques to predict interlayer shear strength (ISS). Feed-forward artificial neural networks (ANN) and random forest (RF) models were developed and compared with traditional multiple linear regression (MLR). Utilizing 156 datasets, divided into 70% training and 30% testing, model performance was assessed using R-squared, mean squared error (MSE), root mean squared error (RMSE), and mean absolute error (MAE). SHapley Additive exPlanations (SHAP) was utilized for model interpretation. The results indicated that the ANN and RF models outperformed MLR, explaining over 95% of experimental data. RF exhibited superior performance with lowest MSE, RMSE, and MAE (0.0029, 0.0538, and 0.0376 MPa). SHAP analysis highlighted the significance of temperature, normal stress, shear deformation rate, and curing time as influential variables in ISS prediction. Elevated temperature adversely influenced ISS, while normal stress, shear deformation rate, and curing time positively contributed to ISS. [ABSTRACT FROM AUTHOR]

The colonisation of building materials by microorganisms is the first step in terms of a subsequent biodeterioration and an occurrence of potential building-associated health hazards. Contrary to many studies to date, focusing mainly on old buildings with symptoms of biocorrosion, this research focuses on the bioreceptivity of selected unused building materials and the factors determining the intensity of their colonisation. The experiments were carried out in parallel in India and Poland, with the use of indigenous microflora from a given region. They revealed the similar dynamics of the microbial multiplication in concrete and plasterboard and the extreme intensity of the process: after only 10 weeks under favorable conditions, the number of bacteria and fungi reached 107 CFU/g of dry weight of the material. The stimulation of microbial growth by individual environmental factors was slightly different in Indian and Polish studies: in India, the strongest stimulating factor was the periodic increase in humidity, while in Poland, the highest intensification of growth was observed in samples enriched with organic matter. Mould biodiversity turned out to be higher in India, although some types of fungi common to both regions were isolated. [ABSTRACT FROM AUTHOR]

The ductile-to-brittle transition (DBT) is an important characteristic that restricts the use of body-centered cubic metals as structural materials at low temperatures. This study shows a design of heterogenous lamellar microstructure (HLM), which is implemented in a low-density steel to promote the occurrence of delamination parallel to the direction of the main crack propagation, and result in delamination toughening effect. When the Charpy impact test temperature was reduced from room temperature to −196°C, the impact absorbed energy displayed a linear decline. The design of HLM brings a new pathway for developing economical BCC-structured metal plates with reliable low-temperature toughness. This is the first time of utilizing 'delamination toughening' to fully suppress the ductile-to-brittle transition in a body-centered cubic metal plate. [ABSTRACT FROM AUTHOR]

In this research, we used a self-developed compact D-D neutron generator and designed a neutron radiation biological device. The research results showed that lead was the material with the best neutron permeability; thus, hard lead was selected as the structural material for this device. Our research disclosed a phenomenon that differed from conventional wisdom, namely, the dose contribution of the neutrons reflected from the hard lead material at the top of the device was about twice that of the polyethylene material. Therefore, hard lead was also selected for the material of the top reflector in this device. The study also showed that the device had good dose uniformity, and the standard neutron absorption dose in each irradiation zone could be obtained according to the simulation results. This device may further promote the development of future research work such as neutron radiation biological effects and mutation breeding. [ABSTRACT FROM AUTHOR]

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This study investigates the feasibility of utilizing ureolytic-type bacteria in lightweight foamed concrete to enhance its compressive strength. Previous research focused on microorganisms in different types of concrete, but there is a lack of study on microorganism incorporation in low-density foamed concrete. Bacillus megaterium was introduced in the production of microbial-based lightweight foamed concrete, inducing mineral precipitation through microbial activities. Four mix proportions were prepared: a control mix (LFC-CM) and LFCs incorporated with varying concentrations of B. megaterium. All specimens underwent water curing. Results show significant improvements in compressive, flexural, and splitting tensile strengths of microbial-based LFC compared to control samples due to microbial-induced calcite precipitation. This research has implications for sustainable construction materials. The potential future directions include optimizing microbial dosage, exploring different ureolytic bacteria, and investigating the long-term durability and performance of microbial-based lightweight foamed concrete. This study contributes to knowledge on microbial-based construction materials, providing insights for sustainable concrete solutions. [ABSTRACT FROM AUTHOR]

We used powder hot extrusion followed by annealing to fabricate a dual-phase AlCoCrFeNi2.1 eutectic high-entropy alloy consisting of both non-recrystallized and recrystallized grains with dense nano-sized precipitates arranged in heterogeneous structures. The resulting alloy exhibits superior tensile properties with a yield strength of ∼1.2 GPa, an ultimate tensile strength of ∼1.5 GPa, and a uniform elongation of ∼18%. Such multiscale microstructure results in exceptional strain hardening of the AlCoCrFeNi2.1 alloy by activating remarkable hetero-deformation induced (HDI) stresses. Our study provides an effective approach to fabricating high-performance structural materials via dual-phase heterogeneous microstructure design. [ABSTRACT FROM AUTHOR]

In this review, a highly pertinent and debatable issue in the maritime industry has been addressed. Although fracture mechanics theories have expanded substantially in recent decades, researchers of the present era in the marine industry still pay little attention in incorporating fracture characteristics into account while designing the structural components. Besides the fundamental strength characterization methodologies, which include establishing the ultimate strength, hardness and impact characteristics, the authors firmly advocate that the fracture parameters of the marine-grade materials must be carefully considered during structural design phase, decidedly for weldments of similar and distinct materials. Nonetheless, these types of paradigms are an inevitable part in prominent sectors, viz., nuclear reactors, pipeline industry and space missions. Owing to this, fracture mechanical investigations performed in marine fields incorporating the standard fracture parameters like stress intensity factor (K), J-integral (J), etc. are thoroughly discussed in this review. The application of different specimen types, viz., compact tension (CT) specimens, single edge notched bend (SENB) and single edge notched tension (SENT) specimens, is also succinctly summarized. The shortcomings of the experimental studies are suggested, and a thorough discussion is also done regarding the potential application of fracture mechanical characterization on marine grade materials and their weldments. [ABSTRACT FROM AUTHOR]

Water treatment plants (WTPs) produce thousands of tons of sludge annually, which is destined for landfill disposal, an environmentally and economically impractical alternative. Chemical, mineralogical, and morphological characterization besides environmental classification has been performed for WTP sludge and it was evaluated application potential in building materials, from a literature review. The characterization was carried out by X-ray fluorescence spectrometry, X-ray diffraction, scanning electron microscopy analysis, and leaching and solubilization tests. The results show that the presence of activated charcoal residues from water treatment in one type of sludge was of little relevance for changes in the properties of the waste. Both sludges have a wide range of particle sizes, consisting mainly of silica, aluminum and iron oxides, as well as kaolinite, quartz, and iron minerals. Special attention must be paid to the solubilization of metallic contaminants to avoid contamination risks and order to make the application safer and more effective, it is necessary to study deeply ways to inert the WTP sludge. The sludges studied have a high potential for application in ceramic products, mortars, geopolymers and concrete paving stones. Depending on the type of building material, different contents of sludge in natural or calcined state can be incorporated. [ABSTRACT FROM AUTHOR]

A large amount of cesium hydroxide (CsOH) is generated during a light water reactor severe accident (SA) and transported through leaky parts to the environment. During that process, some CsOH may interact with oxidized structural materials and change their physicochemical properties. Accurate examination of this interaction is required by source term analysis to derive consistent and appropriate source term transport models, i.e., for SA, decommissioning, and dismantling work of a nuclear reactor. To obtain detailed interaction characteristics, in this study CsOH was exposed to Fe3O4/Fe2O3 and Cr2O3 under a simulated SA environment over a wide temperature range, from 300°C up to 1050°C. As a result, Cs2FeO4, CsFeO2, and Cs2CrO4 were observed at respective temperatures. Cs2FeO4 is stable only at low temperatures and decomposes to form CsFeO2 at about 591°C. However, both Cs2FeO4 and CsFeO2 could react with Cr2O3 to form more stable Cs2CrO4, which melts at 957°C and then completely evaporates at higher temperatures. [ABSTRACT FROM AUTHOR]

Modern concrete technology places a strong emphasis on incorporating diverse resources, particularly industrial byproducts, into the concrete production process. The utilization of fly ash, a notable industrial waste, has gained increasing importance due to its potential to enhance concrete properties and provide economic advantages. In this study, we conducted experimental investigations on concrete, varying the concentrations of graphene oxide (ranging from 0.1% to 0.5%) and coal ash (at levels of 5%, 10%, and 15%). We evaluated the mechanical characteristics of concrete, including compressive strength, tensile strength, and flexural strength, by creating a total of 45 different mix specimens across 15 distinct mix formulations. Remarkably, the combination known as 4GOCA (Graphene Oxide and Coal Ash at 5%, 10%, and 15%) exhibited the highest strength, demonstrating a remarkable 65% increase compared to the reference mix. Similarly, both 2GOCA and 3GOCA demonstrated strength gains exceeding 50%. The unique aspect of this research lies in its innovative utilization of graphene oxide and coal ash in the concrete mix, showcasing the potential for sustainable and high-performance construction materials. [ABSTRACT FROM AUTHOR]

The factors of the building's structure's overstrength performance need to be researched to decrease the large amount of the structural materials and the investments caused unreasonably by the overstrength performance. Taking the Guangzhou West Tower as an example, the main reasons why the Guangzhou West Tower model structure was not damaged after encountering an earthquake (PGA = 620 gal) in the shaking table test was revealed. The overstrength performance of lateral force-resisting system of the Guangzhou West Tower building's structure was researched, which is caused by the artificially adjusted earthquake influence coefficient of the long-period segment of response spectrum. The response spectrum analysis and the elastic/plastic incremental dynamic time history analysis were conducted to obtain the overstrength coefficient of the lateral force-resisting system that was calculated with the overturning moment at structural base. The analysis results showed that the yield overturning moment at structural base exceeds the seismic demand at the point where PGA = 400 gal, which could verify the reliability of the results of shaking table test. The artificial magnification of the long-period segment of response spectrum and the irrational correlation between the seismic grade and the building's height are important reasons that increase the overstrength capacity of long-period building's structure. [ABSTRACT FROM AUTHOR]

This study aims to find solutions to the weak water resistance problems of earthen buildings and reduce the frequency of the periodic maintenance they require by using admixture materials in the production of soil building materials which will be tested for their effectiveness in the enhancement of earthen buildings' water resistance. In the study, the chemical and mineralogical properties of the cohesive (clayey) soil material, which is locally called 'Gavcin' and used on flat soil roofs in the Kemaliye district of Erzincan province, were determined by XRF and XRD methods whereas the grain size distributions of them were analyzed through granulometric and hydrometric analysis. For the analysis, six different admixture materials were mixed with the original material and the liquid limit (WL), plastic limit (WP), plasticity index (IP), and soil's natural unit volume weight of the original material versus the admixture-added materials were determined. Mortars were produced with original and additive materials in order to determine their physical properties. Unit volume weights, specific gravity, density, compaction-porosity, weight water absorption potential, hardened volumetric water absorption and capillary water absorption (capillarity) capacities of the produced mortars were determined on the 28th and 365th days, respectively. In terms of consistency limits, the most satisfactory experimental results were obtained from G3 and G7 samples (29.3% and 31.3% of Liquid limits and 27.9% and 27.4% of plastic limits). In addition, these two specimens were observed to be most resistant specimens to capillary suction at the end of 28 and 365 days. [ABSTRACT FROM AUTHOR]