Water Absorption Research Articles

Cement Board Using Discarded Peanut Shell (Arachis Hypogaea)

This study investigates the use of powdered peanut shells as a sustainable alternative in cement board production. With the growing emphasis on eco-friendly construction materials, exploring alternative resources is essential. Cement boards were fabricated incorporating powdered peanut shells at varying percentages (5%, 10%, and 15% by weight) relative to the total weight of the cement mixture. The preparation involved calculating the sample volume, adjusting the mixture weight to account for the peanut shells, and setting the water-cement ratio to 0.46. The process included grinding the peanut shells, measuring all components, and thoroughly mixing them before molding. The mixtures were cured in a controlled environment to promote proper setting. The physical, mechanical, and thermal properties of the resulting boards were evaluated according to ASTM standards and analyzed using SPSS. Notably, the 5% mix achieved the highest density (1.60 g/cm³) and demonstrated excellent heat resistance, while the 15% mix exhibited the greatest thickness (1.24 cm) and lowest water absorption (10.99%). The 10% mix resulted in the highest compressive (11.28 MN/m²) and tensile strengths (0.24 N/cm²). The findings suggest that incorporating powdered peanut shells significantly improves the properties of cement boards, presenting a viable and sustainable construction option. Future studies should focus on optimizing these mixtures and assessing their long-term durability.

Advancements in Geopolymer Concrete for Marine Infrastructure: An Optimization of Performance Considering Workability, Compressive Strength, Capillary Water Absorption, Porosity, and Chloride Migration

Advancements in Geopolymer Concrete for Marine Infrastructure: An Optimization of Performance Considering Workability, Compressive Strength, Capillary Water Absorption, Porosity, and Chloride Migration

Study on the impact of water absorption processes on the application of wood waste in composite material production

The issue of recycling and reusing waste from the wood processing industry has garnered significant attention from researchers, as effective solutions could yield economic benefits while mitigating environmental impacts. This article focuses on the development of artificial wood using unsaturated polyester resin combined with waste materials from carpentry workshops, specifically investigating its water absorption properties. Research findings indicate that the water absorption coefficient of the samples increased with longer immersion times, higher organic filler content, and larger particle diameters. The calculated density reveals a broad spectrum of solid industrial boards that can be produced from these compositions, suggesting that consistent forming conditions enhance economic viability. Notably, optimal results were achieved with samples made from mixed wood powder without prior sorting, which contributes to reduced production costs, aligning with the study's objectives. Furthermore, the investigation highlighted that the water absorption coefficient escalates with increased soaking time, organic filler content, and particle size, indicating that in humid environments, it is advisable to limit both filler content and particle size to maintain performance. Overall, the studies confirm the feasibility of utilizing wood powder as a filler, with varying particle diameters imparting distinct characteristics to the final product. These findings underscore the potential for innovative approaches to wood waste management in the industry.

Experimental research on mechanically and thermally activation of nano-kaolin to improve the properties of ultra-high-performance fiber-reinforced concrete

Abstract The rising demand for ultra-high-performance concrete (UHPC) necessitates innovations in sustainable materials. This study explores the substitution of ordinary Portland cement (OPC) with thermally and mechanically activated nano-kaolin in varying proportions from 0.5 to 0.25%. A uniform quantity of double-hooked end steel fibers was added to all the mixes. Activated nano-kaolin variants showed significant enhancement in UHPC properties. Specifically, UHPC with 0.20% thermally activated kaolin (B3-TAK-20) exhibited a 21.6% increase in compressive strength and a 25.5% increase in modulus of elasticity at 90 days, with the modulus of rupture doubling compared to the reference mix. These improvements are attributed to the amorphous nature of thermally activated nano-kaolin, resulting in a denser concrete matrix and reduced porosity. Beyond the optimal 0.20% kaolin replacement, an increase to 0.25% diminished compressive strength. Durability tests showed enhanced acid resistance, with only a 6.7% mass loss for the thermally activated nano-kaolin mix and a consistent reduction in water absorption by 14.4% as kaolin proportions increased from 0.5 to 0.25%. The study also noted a decrease in water absorption by 22.9 and 12.3% at 56 and 90 days, respectively, indicating the thermally activated nano-kaolin’s enhanced performance. This research underscores the potential of activated kaolin as a viable alternative to OPC, paving the way for more sustainable UHPC production.

Environmental Conservation by Using Recycled Aggregates: Enhancing Sustainability in Road Construction

Every day, construction and demolition waste is generated worldwide. As the road business and traffic grow, construction materials have evolved to include more unorthodox features. Road construction and maintenance rely significantly on quarried aggregates, resulting in high resource extraction demands. There is a trend toward employing secondary (recycled) materials rather than primary (virgin) ones to address this. This transformation requires the use of a variety of secondary and tertiary components, including waste byproducts. Numerous studies have been conducted to study and analyze the suitability and practical application of recycled materials in the field. Some recycled materials have better qualities than others, proving satisfactory performance in real-world circumstances. However, concerns about their incorporation persist, based on laboratory research and field observations. These concerns emphasize the necessity for more in-depth research to address potential difficulties. It is claimed that using recycled and tertiary materials in road construction can greatly help to save natural resources. This study predicts the attributes of selected materials, such as gradation, water absorption, maximum dry density, impact value, flakiness, and elongation, to establish their appropriateness for the production of Granular Sub-base (GSB) and Wet Mix Macadam (WMM).

PLASTIC BLOCK FOR BUILDING CONSTRUCTION MATERIAL

Plastic wrap waste increase from time to time. Efforts are needed to utilize them as they are less demanded for recycling by the private sectors in Bali and Indonesia. This paper describe effort to use combination of waste thin plastic wrap as plastic block for wall construction material. The plastic wrap wastes were cut into 5-10 mm size, then they were melted in a hot waste engine oil at 200°C. The mixture was then poured into a metal mold, slightly cooled down and compressed using a compression machine. The mixtures produced was without and with added rice husk ash as filling material. The size of the plastic block was 20×10×8cm. It was found that the densities of the samples were less than 1gram/cm3, the compressive strength can achieve 25kg/cm2, the Porosities were low, ranges from 0.220-0.290%, the Initial Rate of Suctions (IRS) were very low ranges form 0.0004-0.00075 kg/m2.minute, and the and water absorptions were also low (0.02-0.03) %. In general, the compressive strengths were comparable to low quality bricks commonly produced.

Microstructural Evolution and Damage Mechanism of Water-Immersed Coal Based on Physicochemical Effects of Inorganic Minerals

Coal seam water injection technology enables seam permeability enhancement and facilitates outburst risk reduction. This study investigated the microscale effects of water infiltration on coal and the evolution mechanisms of its mechanical properties. To this end, we systematically analyzed dynamic changes (such as mineral composition, pore structure, and mechanical performance) in coal soaked for various durations using X-ray diffraction, low-field nuclear magnetic resonance (NMR), and uniaxial compression testing. The results indicate: (1) the coal NMR T2 spectrum displays three characteristic peaks, corresponding to rapid water absorption, uniform transition, and stabilization stages of soaking traditionally divided according to peak area variation trends. (2) The coal strength decreases with progressive soaking, influenced by water content, pore volume, mineral composition, etc. Its compressive strength and elastic modulus drop by 22.4% and 19.5%, respectively, compared to the initial values. (3) The expansion of clay minerals during immersion reduces average pore size. In contrast, quartz particle displacement, pore water movement, and soluble mineral dissolution increase pore volume, reducing the overall structure strength. (4) The dominant factors driving the degradation of mechanical properties vary across immersion stages, including water content and specific mineral concentration. This work offers new insights into how hydraulic technology alters coal seams, providing theoretical support for optimizing water injection strategies in the seam.

Evaluation of the performance of low-fat (oil-fat) dressings based on chemically modified Guayabo plantain starch (Musa paradisiaca L.).

Guayabo plantain (GP) starch was chemically modified by acetylation to evaluate its role as a stabilizer and emulsifier in low-fat dressings. Native starch (NS) from GP was chemically modified starch (MS), and its functional properties, such as water absorption index, water solubility index, swelling power, gelatinization temperature (Tg), were evaluated. Additionally, functional groups and morphology were identified using Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy. Low-fat dressings were prepared using NS and MS at two concentrations, 2% and 3% (NS2, NS3, MS2, MS3), and the stability of the dressings was evaluated over a storage period of 28 days at 4 °C ± 2.0 °C. The percentage of acetylation and the degree of substitution obtained were 2.48% and 0.01, respectively, complying with current regulations. MS showed a higher amylose content (23.62 ± 1.89%) than NS (16.01 ± 0.43%). The Tg of MS decreased, and the appearance of bands at 1012 and 1723 cm-1 in the FT-IR spectra suggested a modification in the functional characteristics of starch due to acetylation. Emulsions of MS at 2% and 3% (MS2 and MS3) showed a smaller droplet size and higher interfacial dispersion. However, MS3 had higher viscosity, which contributed to an increase in hydrophobicity and delays in flocculation and subsequent coalescence. This research study provides useful information on the use of 3% MS dressings in new food formulations, reducing fat content while preserving functional characteristics, thus ensuring greater stability.

Enhancing crack self-healing properties of low-carbon LC3 cement using microbial induced calcite precipitation technique

Limestone Calcined Clay Cement (LC3) is a promising low-carbon alternative to traditional cement, but its reduced clinker content limits its self-healing ability for microcracks, affecting durability. This study explores the application of Microbial Induced Calcite Precipitation (MICP) technique to enhance the crack self-healing capacity of LC3-based materials. Bacillus pasteurii was utilized to induce calcium carbonate precipitation to improve the crack self-healing capacity of LC3, thereby addressing its limited durability due to reduced clinker content. Experimental tests focused on optimizing the growth conditions for B. pasteurii, evaluating the compressive strength, capillary water absorption, and crack self-healing rates of the modified LC3 material. Results showed that under optimal conditions (pH of 9, inoculation volume of 10%, incubation temperature of 30°C, and shaking speed of 150 rpm), the bacterial strain exhibited maximum metabolic activity. The Microbe-LC3 mortar demonstrated a self-healing rate of up to 97% for cracks narrower than 100 μm, significantly higher than unmodified LC3. Additionally, the compressive strength of Microbe-LC3 was enhanced by approximately 15% compared to standard LC3 mortar after 28 days. The capillary water absorption was reduced, indicating improved durability due to the microbial-induced calcium carbonate filling the pores. This study confirms that MICP technology is a viable approach to significantly enhance the performance of LC3, contributing to the development of more durable and sustainable cementitious materials for construction applications.

Restructuring the Basic Design of Several Accelerator-Based Concrete Mixes by Integrating Superplasticizers

The increasing demand for infrastructure, the need to consolidate aging structures, and the effects of climate change imply the replacement or improvement of traditional concrete. This study investigates three accelerators and their mixtures (Ca(NO3)2·4H2O, Al2(SO4)3·18H2O, and Na2S2O3·5H2O) (series I) and their counterparts with superplasticizers (Dynamon SR41) (series II) as additives in standard concrete to improve its functionality. The standard concrete and new concrete mixes were analyzed using X-ray diffraction (XRD), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX), and tests for water absorption, bulk density, and compressive strength. XRD analysis showed that all concrete mixes had similar structures composed of quartz, portlandite, larnite, calcium silicate, ettringite, albite, and muscovite in varying proportions. Their microstructures, as shown by SEM images, revealed the presence of ettringite, portlandite, and C-S-H gel at high magnification (1–5 kx). The addition of the superplasticizer remodeled the surface of the concrete mix, reducing the pore radius and increasing its compaction. These changes helped to reduce its bulk density while increasing the compressive strength. The results showed that all the concrete mixtures are similar to the standard concrete and can replace it for better functionality, but Na2S2O3·5H2O with superplasticizer concrete mixture had the higher compressive strength, supplying additional benefits.

Enhanced mechanical and self-healing properties of rice husk ash-incinerated sugarcane press mud biogeopolymer pastes.

This study examines the use of rice husk ash (RHA) and incinerated sugarcane press mud (ISPM) as precursors in the lime/pozzolan geopolymer system and the effect of the bacterium Lysinibacillus sp. WH on the mechanical properties and microstructures. The RHA-to-ISPM ratio was varied, and the geopolymer pastes were cured at ambient temperature. The results show that an increase of ISPM content up to 5% improves strength and reduces water absorption and voids, while higher ISPM levels beyond 5% degrade the quality of geopolymer paste. An increase in ISPM content reduces setting times due to an increase amount of calcium in the pastes. Notably, the addition of bacteria resulting in a reduction of setting times has been proved for the first time in this work. Moreover, the addition of bacteria can enhance all mechanical properties and introduce self-healing abilities, with microcracks healing within < 20 days of treatment, regardless of mix proportions. Microstructural studies, using a scanning electron microscope (SEM), Fourier Transform Infrared Microscopy (FT-IR), X-ray diffraction (XRD), and Rietveld refinement analysis, reveal that bacteria increase cristobalite, and decrease quartz, thus resulting in strength enhancement of geopolymer pastes. Furthermore, this work is the first to provide evidence that bacteria tend to reduce the efflorescence formation as confirmed by a decrease in gaylussite. These findings pave ways to the production of more sustainable geopolymer systems via upcycling wastes and prolonging service life due to bacterial activity.

Effect of N,N′-Methylenebisacrylamide on properties of porous semi-IPN hydrogels from Acrylamide, Maleic Acid, and its use for Urea absorption

Hydrogel is a three-dimensional polymer that can absorb large amounts of reagents while maintaining structural integrity. This material has been applied in many fields especially in smart agriculture. To improve the economic viability, the reusability of hydrogels in agricultural engineering over multiple cycles of adsorption and desorption is an urgent requirement. This can be solved if the crosslinker is used properly. Therefore, in this work, a series of porous semi-IPN hydrogels based on linear polyacrylamide, acrylamide, maleic acid, and N,N′-methylenebisacrylamide (MBA) were synthesized. The hydrogels were evaluated for the impact of MBA content on the characteristics and applicability as a urea fertilizer carrier. The chemical composition, morphology, mechanical, and rheological properties, swelling behavior, urea absorption and desorption of hydrogels with crosslinker content in the range of 0.5-2.0 % were investigated. The porous structure was confirmed by scanning electron microscopy images. Changing the MBA content significantly affected all characteristics of the hydrogels. In particular, increasing the MBA content decreased the equilibrium swelling ratios in all investigated environments. The maximum amount of urea loaded into the hydrogel was also reduced from 435.88 to 188.50 mg/g. This increase also changed the swelling mechanism from non-Fickian to Fickian, whereas the urea release mechanism changed from Fickian to non-Fickian. Finally, the hydrogels demonstrated stability in soil over multiple cycles of water absorption and release. This study provides valuable insights into designing a semi-IPN hydrogel with desired properties that meet the application requirements of modern farming techniques.

Comparative study of fibers extracted from the stems and roots of the Cameroonian pennissetum purpureum for their applications in compressed earth brick reinforcement and textile engineering

This work focuses on the extraction and experimental characterization of pennisetum purpureum fibers extracted from stems and roots, harvested in the Batié Kingdom, in the West Region of Cameroon. After extracting fibers using the boiling water technique, they are chemically treated to improve their properties and performance and to facilitate their incorporation into various composite materials. For the physical characterizations, it is measured: the absolute and apparent densities, the linear mass, the water absorption rate, and the diameter via the microscope. The mean values of the diameters and the measure of their frequency distributions are calculated, followed by the statistical analysis using the maximum entropy principle, in order to find the most probable diameter necessary for technological applications. For the mechanical properties, only the tensile tests are performed, with the determination of the young modulus of both the stems and roots. The results thus obtained showed that the fibers of the stems have an absolute density of (1.35 g/cm3), a linear mass of (54.6 tex), an apparent density of (0.45 g/cm3), a water content of (12.73%), an absorption rate of (142.46%), a porosity of (65.91%), a mean diameter of (7 mm), an elastic modulus of (3.98 GPa), a tensile strength of value of (1186.59 MPa) and an elongation of 16.17%, while the root fibers have an absolute density of (1.34 g/cm3), a linear mass (16.76 tex), an apparent density of (0.37845 g/cm3), a water content of (12.25%), an absorption rate of (193.16%), a porosity of (71.92%), a diameter of (4 mm), an elastic modulus of (1.55 GPa), a tensile strength of a value of (1960.35 MPa) and an elongation of 60.6%. Thus, the fibers of the stems have good mechanical properties, which make them an appropriate material in several applications, such as the reinforcement of composite materials.

All-natural, hydrophobic, biodegradable cellulose-based straws through simultaneous esterification and filling with stearic acid for cold beverages.

Disposable plastic straws have caused severe environmental pollution because microplastics produced in the degradation process harm human health and marine ecosystems. Paper straws as substitutes need to be incorporated into hydrophobic agents and other chemicals to achieve hydrophobicity, which may be harmful to human health. In this study, a novel and purely natural hydrophobic cellulose-based straw was made from bleached bamboo fibers (BBF) and stearic acid (SA). The prepared straw (BBF/SA@straw) exhibited improved hydrophobicity, biodegradability, and applicability. The water absorption rate was maintained at 58.66 % using single-factor analysis and response surface methodology and the maximum water contact angle was up to 133o. Additionally, the paper straw was almost completely degraded after 50 days in soil. Moreover, it could be used normally in water at 0 °C and 25 °C and was suitable for various beverages (tea, coffee, coke, and milk), demonstrating an extensive application prospect. This work supplies a promising and green alternative to plastic straws, alleviating the burden of white pollution in the environment.

Engineering characteristics of one-part alkali-activated slag-based paste incorporating nano-silica and calcined oyster shells ash

ABSTRACT This study investigates the influence of nano-silica up to 5% by mass on the hydration, engineering properties, and microstructure of one-part alkali-activated slag-based paste with up to 20% calcined oyster shell ash (COSA). Adding nano-silica reduced workability and accelerated setting times. A mixture with 3% nano-silica and 20% COSA showed a 31.55% increase in compressive strength, improved thermal conductivity from 0.434 W/(m · K) to 0.715 W/(m · K), and reduced water absorption from 10.43% to 3.02% when compared to those mixtures with only COSA. These improvements are due to nano-silica interacting with calcium hydroxide, forming hydration products such as ettringite and C-S-H gel, which fill micropores and strengthen the microstructure. This rapid hydration and strength development make it ideal for precast manufacturing. Thus, incorporating nano-silica allows efficient use of up to 20% COSA, making it a sustainable and eco-friendly construction material.

Impact of geopolymer aggregate on the mechanical properties and durability characteristics of concrete

This study examined the use of geopolymer aggregate (GPA), produced from slag and an alkaline solution, as a substitute for coarse aggregate in conventional concrete. The research aimed to evaluate how different proportions of GPA (25%, 50%, 75%, and 100% replacement) affect the durability and mechanical properties of concrete. A series of tests were conducted, including slump, compressive strength, flexural strength, chloride resistance, sulfate resistance, sorptivity, and water absorption. The results demonstrated significant improvements in concrete properties with the inclusion of GPA. The compressive strength of GPA concrete ranged from 31 to 38 MPa, showing a 10%–15% increase over that of standard concrete. Flexural strength improved by 6% at 7 days and 7.5% at 28 days compared to control mixes. Water absorption was reduced by 42.58%, and sorptivity decreased by 47.9% compared to ordinary aggregate concrete. GPA concrete also excelled in acid resistance, with a weight loss of 28.6% and a lower reduction in strength compared to traditional acidic aggregates. In sulfate resistance tests, GPA concrete showed a 31% reduction in both weight and strength loss. These results highlight the advantages of using GPA as an alternative to conventional coarse aggregates. GPA not only enhances the mechanical and durability properties of concrete but also presents a more sustainable option, contributing to reduced environmental impacts associated with traditional aggregate materials.

Investigation of the effect of urease bioadditives on porosity and water absorption of cement composites

The results of the application of the biomineralization process in concrete to improve concrete properties such as porosity and water absorption are presented. As a result of the research, an assessment of the activity of various bioadditives based on the Bacillus subtilis strain and isolates isolated from samples of chernozem soil of the Yelets district of the Lipetsk region was given.It was found that the immobilized bacteria slightly differ from the native form in terms of urease activity, however, when stored for more than 50 days. they maintain their activity at a high level, and native microorganisms lose their ability to function, reducing urease activity by 10 times practically to minimum values. It was also revealed that when using Portland cement of various types, there is a decrease in water absorption up to 30%, and porosity decreases up to 40%.The use of different types of fine aggregate also affects porosity, so when using the same parts of sand P1 and P2, porosity is lower than with a homogeneous fine aggregate.It was also noted that all samples had increased strength characteristics – compressive strength and bending strength by 15–25%, respectively. Thus, the use of bioadditives is optimal to achieve improved concrete characteristics.

High‐performance engineered geopolymer composites: A sustainable approach using recycled brick waste

AbstractThis study examines the viability of using construction waste, specifically recycled brick waste powder (RBWP), as an alternative conventional industrial byproduct (fly ash) in the manufacturing of engineered geopolymer composites (EGC). The EGC mixtures are made with 40 μm diameter and 12 mm length polyvinyl alcohol (PVA) fiber. RBWP replaces class‐F fly ash in EGC by 0, 20%, 40%, 60%, 80%, and 100%. This study produces six distinct EGC mixtures in total. The flexural strength, abrasion resistance, sorptivity, and water absorption of the EGC are investigated. Microstructural characterization is carried out using scanning electron microscopy (SEM). Based on the results, when fly ash is replaced by 40% and 100%, respectively, adding RBWP to the EGC mixes significantly improves flexural strength by 39% and midspan deflection by 169%. Nevertheless, abrasion resistance significantly improves when fly ash is completely replaced with RBWP, even though sorptivity and water absorption increase by about 128% and 240%, respectively. The volume change is reduced by 25.4% when RBWP is used. Furthermore, the SEM study shows that the RBWP undergoes active geopolymerization in the EGC mixes.

Effect of Different Admixtures on Mechanical Properties of Concrete Paving Block: A Comparative Study

Ever since their introduction nearly a century ago, concrete paving blocks have become increasingly common. They evolved into an alternative to burned clay brick and natural stone. Concrete paving blocks are used to lay down areas for vehicles and pedestrians as well. Durability is one of the most crucial elements in the production of high-quality concrete paving blocks. The aim of this study is to optimize the mechanical properties of concrete paving block units by experimenting with different admixtures. Compressive strength, water absorption, oven dry density, and drying shrinkage are among the attributes that were evaluated. The cost of production was also contrasted with and without the use of an admixture to achieve a comparable compressive strength. The results showed that admixtures could be used to produce high early strength units, and this was considered to be an economical factor in the production of concrete paving block units. At all ages, the use of admixtures increased these units' compressive strength by 30–40%. Although they did slightly increase density, additives also decreased the absorption and drying shrinkage of concrete paving block units.

Enhancing green polyethylene composites with filler heat treatment: Pecan nutshells and Pinus sawdust impact

The aim of the present study was to produce sustainable composites using green low-density polyethylene (LDPE) reinforced with heat-treated lignocellulosic residues. The transformation processes were employed to enhance the chemical compatibility of lignocellulosic wastes with the polymer matrices of the composite materials. Sawdust from pine wood (PW) and milled pecan nutshells (NS) were subjected to a thermal treatment at 180°C for 2 h. These heat-treated residues were then homogenized with the polymer matrix and molded through hot compression. The resulting wood polymer composites (WPCs) were subjected to various characterization tests, including density, mechanical properties, infrared spectroscopy, thermal stability, hygroscopic behavior, and morphology. Comparing the composites, the inclusion of heat-treated fillers led to reductions in water absorption and thickness swelling, especially for the NS. Furthermore, the composites didn’t exhibit increased flexural strength and/or tensile strength after the bio-components treatment. The insertion of thermally treated lignocelluloses also resulted in slight decreases in equilibrium moisture content and apparent contact angles.