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The brick walls of ancient buildings have got a lot of tiny and closely connected pores inside, so they can soak up water really well. This can easily cause problems like getting powdery and having efflorescence. To stop water from spoiling the grey bricks, this paper focuses on the brick walls of historical buildings in Kaifeng City. Based on our investigation, we study the distribution features of the problems. This paper tells about using the method of negative pressure infiltration to change the grey bricks. We measure all kinds of basic indicators and analyze how different ratios of modifiers affect the water properties and dry-wet cycle tests of the grey bricks. We look at the changes in the inside shape through SEM to show how it changes the grey bricks of ancient buildings. Second, we improve the wet walls by using a way that combines blocking and drainage. The main things we studied and the conclusions are like this: We use sodium methyl silicate and acrylamide polymer as modifiers to soak the historical grey bricks under negative pressure. We figure out the best ratio through orthogonal experiments. We analyze things like the water vapor permeability, how long it takes for a water drop to go through, the compressive strength, the water absorption rate, and the height of water absorption of the modified bricks. The results show that the crosslinking agent and acrylamide monomer have a big influence on how high the capillary water goes up in the modified bricks. The air permeability of the modified grey bricks with acrylamide polymer goes down a bit, but it's still okay. The surface of the modified grey bricks is very hydrophobic and there are fewer pores inside. The mechanical properties of the modified grey bricks get better in different degrees. The water absorption rate and the height of capillary water absorption go down. The modified grey bricks can really cut down the erosion of water on the wall when used in real life. They can reduce salt crystallization and efflorescence caused by rising water, and so make the brick walls of historical buildings last longer. This is super important for protecting historical buildings in Kaifeng City and taking care of other similar structures. Also, by using a way that combines blocking and drainage, and putting polymer infiltration reinforcement and the ventilation of the moisture drainage pipe together, the results show that this combination can really lower the height that capillary water goes up in the brick wall. So we get a way to control how wet the wall is.

期刊论文 2025-07-01 DOI: 10.1016/j.cscm.2025.e04422 ISSN: 2214-5095

Local ecological materials in construction represent a fundamental step toward creating living environments that combine environmental sustainability, energy efficiency, and occupant comfort. It is part of an organizational context that encourages the adoption of these methods and processes. This study aims to improve the use of locally available materials, particularly soil and agricultural residues, in the Errachidia region (southeastern Morocco). In particular, date palm waste fiber, a widely available agrarian by-product, was incorporated into the soil to develop six different types of stabilized earth bricks with fiber contents of 0 %, 1 %, 2 %, 3 %, 4 %, and 5 %. The aim was to evaluate their thermophysical, mechanical, and capillary water absorption properties. Thermal properties were determined using the highly insulated house method (PHYWE), a specific methodology for assessing thermal properties in a controlled, highly insulated environment. In addition, mechanical measurements were carried out to assess compressive and flexural strength. The results obtained showed that the addition of date palm waste fibers to brick based on soil improves the thermal resistance of the bricks. Flexural and compressive strength increased up to 3 % of fiber content, while a reduction was observed above this value. The 3 % fiber content is optimal for the stabilization of brick based on soil. Then, the increase of fiber content in bricks resulted in an increase in water absorption with a decrease in the density of the bricks. Physical and chemical characterization (XRD, FTIR, SEM, and EDX) of the soil and date palm waste fibers was carried out with geotechnical soil tests. The results obtained showed that the soil studied satisfies the minimum requirements for the production of bricks stabilized by fibers. These bricks can be considered an alternative to conventional bricks in ecological construction.

期刊论文 2025-06-01 DOI: 10.1016/j.clwas.2025.100283

Research on the performance of solidified soil in capillary water absorption seawater environments is necessary to reveal the durability under conditions such as above seawater level in coastal zones. Taking soda residue-ground granulated blast furnace slag-carbide slag (SR-GGBS-CS) and cement as marine soil solidifiers, the deterioration characteristics of solidified soil resulting from capillary seawater absorption were elucidated systematically through a series of tests including capillary water absorption, unconfined compressive strength, swelling, local strain, and crystallization. The microscopic mechanism was analysed through nuclear magnetic resonance and X-ray diffraction tests. The results showed that cement-solidified soil exhibited higher water absorption and faster swelling compared with SR-GGBS-CS solidified soil in the one-dimensional seawater absorption state. In the three-dimensional seawater absorption state, solidified soil with low GGBS dosage experienced a significant transition from vertical shrinkage to swelling during the capillary water absorption process, leading to a substantial decrease in strength after 7 days of crystallization. Cement-solidified soil displayed non-uniform and anisotropic swelling, along with the formation of more external salt crystals. Overall, the soil solidified with 25% SR, 10% GGBS, and 4% CS demonstrated robust resistance to capillary absorption deterioration in a seawater environment due to its minimal water absorption and swelling, uniform surface strain, weak salt crystallization, and limited strength deterioration caused by capillary water absorption.

期刊论文 2025-05-19 DOI: 10.1680/jenge.24.00117 ISSN: 2051-803X

Despite its advantages, conventional soil-cement has limitations in terms of mechanical strength and durability, especially in environments with high humidity or high structural demands. The development of high-performance soil-cement (HPSC) presents significantly superior mechanical properties. The decentralized production of these panels has resulted in a cost reduction of more than 40%, making them an affordable alternative for low-income communities. Even so, providing technical support for the popularization of HPSC is crucial for the advancement of civil construction and to enable the expansion of affordable and sustainable housing for vulnerable communities. This study focuses on the development of a high-performance soil-cement panel, including its manufacturing process and the materials used. The panel was produced using Yellow Argisol soil, found locally in abundant quantities, modified with sand. Measurements of flexural strength and water absorption were carried out, together with a comparison of the strength of high-performance concrete (HPC) found in the literature. The developed panels present an average flexural strength of 6.71 MPa. Additionally, water absorption reached 5.99%, indicating the high performance of this material, which is comparable to high-performance concrete but more economical and sustainable. This contribution confirms the viability of transferring HPSC technology and highlights its social impact on civil construction.

期刊论文 2025-05-17 DOI: 10.3390/buildings15101697

Waste tire textile fiber (WTTF), a secondary product from the processing of end-of-life tires, is predominantly disposed of through incineration or landfilling-both of which present significant environmental hazards. The incineration process emits large quantities of greenhouse gases (GHGs) as well as harmful substances such as dioxins and heavy metals, exacerbating air pollution and contributing to climate change. Conversely, landfilling WTTF results in long-term environmental degradation, as the synthetic fibers are non-biodegradable and can leach pollutants into the surrounding soil and water systems. These detrimental impacts emphasize the pressing need for environmentally sustainable disposal and reuse strategies. We found that 80% of WTTF was used for the production of thermal insulation mats. The other part, i.e., 20% of the raw material, used for the twining, stabilization, and improvement of the properties of the mats, consisted of recycled polyester fiber (RPES), bicomponent polyester fiber (BiPES), and hollow polyester fiber (HPES). The research shows that 80% of WTTF produces a stable filament for sustainable thermal insulating mat formation. The studies on sustainable thermal insulating mats show that the thermal conductivity of the product varies from 0.0412 W/(m center dot K) to 0.0338 W/(m center dot K). The tensile strength measured parallel to the direction of formation ranges from 5.60 kPa to 13.8 kPa, and, perpendicular to the direction of formation, it ranges from 7.0 kPa to 23 kPa. In addition, the fibers, as well as the finished product, were characterized by low water absorption values, which, depending on the composition, ranged from 1.5% to 4.3%. This research is practically significant because it demonstrates that WTTF can be used to produce insulating materials using non-woven technology. The obtained thermal conductivity values are comparable to those of conventional insulating materials, and the measured mechanical properties meet the requirements for insulating mats.

期刊论文 2025-05-08 DOI: 10.3390/su17104288

This paper presents the results of experimental testing of adobe masonry assemblages to study their flexure and bond behaviors. The properties of soil and water absorption of adobe units also were investigated. The plasticity index of the soil was 7.56, which was higher than that reported for the adobe soil in a few regions of the world. The silt and clay contents of the soil also were higher than those of the soil used by researchers elsewhere. High water absorption of the adobe units (27.37%) indicated their low cohesion characteristic, which was evidenced by low bond strength. The flexural strength of the wallettes tested in a direction parallel to the bed joints was less than that of those tested perpendicular to the bed joints. The tensile bond strength determined by the bond wrench method was considerably smaller than the flexural strength of the wallettes. The observed flexural and bond strengths of the adobe masonry also were smaller than those reported in the literature.

期刊论文 2025-05-01 DOI: 10.1061/JSDCCC.SCENG-1632 ISSN: 2996-5136

In this research, the effect of using alpha fibres on the physico-mechanical properties of compressed earth bricks (CEBs) was investigated. CEBs were produced using soil, lime and different amounts (0%, 0.5%, 1%, 1.5% and 2%) of raw (RAF) or treated alpha fibres (TAF). First, the diameter, density and water absorption of RAF and TAF were determined. Then, the produced CEBs reinforced by these fibres were subjected to compressive strength, thermal test, density and capillarity water absorption tests. The obtained results showed that the addition of RAF and TAF leads to a reduction of the thermal conductivity by 33% and 31%, respectively. The finding also indicated that the density was decreased by 26% and 17% with the inclusion of TAF and RAF respectively. Besides, the compressive strength was reduced and water absorption coefficient was increased when fibres reinforced CEBs but remaining within the standard's recommended limits. Moreover, the addition of fibre improves the acoustic properties of samples by 98%. The CEBs developed in this paper could be an alternative to other more common building materials, which would lead to a reduction of energy demand and environmental problems.

期刊论文 2025-04-04 DOI: 10.1080/19648189.2024.2422362 ISSN: 1964-8189

The issue of water-enriched surrounding rock induced by excavation disturbances in loess tunnels represents a significant challenge for the construction of loess tunnel projects. Based on the concepts of lime sac water absorption, expansion, and compaction, consolidation, and drainage of surrounding rock and soil, as well as active reinforcement, a tandem water-absorbing and compaction anchor with heat-expansion and compaction consolidation functionality has been developed. To facilitate the engineering design and application of this novel anchor, a consolidation equation for cylindrical heat source-consolidated soil was derived under conditions of equal strain and continuous seepage. Considering the impact of temperature in the thermal consolidation zone on soil permeability, an analytical solution for the average degree of consolidation of the surrounding soil after support with the water-absorbing and compaction anchor was provided. The correctness of the solution was verified through engineering examples, demonstrating the reasonableness of the theoretical calculation method used in this study. The analysis of consolidation effects in engineering examples demonstrates that the excess pore water pressure in the borehole wall area dissipates rapidly after reaming, exhibiting an exponential decay over time. By the 100th time step, the pore pressure decreases from 100 kPa to 63.2 kPa. As consolidation continues, by the 1000th time step, the pore pressure further reduces to 21.6 kPa. The region with significant changes in pore pressure amplitude is primarily located within the plastic zone of the reamed hole, while the rate of pore pressure change in the more distal elastic zone is generally lower. The consolidation process effectively dissipates the excess pore water pressure and converts it into effective stress in the soil, indicating a notable active reinforcement effect of the water-absorbing compaction anchor. Within the plastic zone, the attenuation rate of excess pore water pressure is 85%. Under different drainage conditions at the borehole wall, the dissipation rate of excess pore pressure in Model 1 (Assuming drainage conditions around the water absorbing anchor rod) is greater than that in Model 2 (Assuming that there is no drainage around the water absorbing anchor rod), with the average degree of consolidation in Model 1 being 22% higher than in Model 2. Under the conditions of Model 1, the active reinforcement effect of the water-absorbing compaction anchor is more pronounced, providing better reinforcement for the surrounding rock and soil. To ensure the reinforcement effect, the theoretical design should consider a certain surplus in the filling quality of the lime water-absorbing medium. The research findings are of significant importance for advancing the theoretical structural design and engineering practical application of this new type of anchor.

期刊论文 2025-03-31 DOI: 10.1088/2631-8695/adbe27 ISSN: 2631-8695

Plant-based macromolecules such as lignocellulosic fibers are one of the promising bio-resources to be utilized as reinforcement for developing sustainable composites. However, due to their hydrophilic nature and weak interfacial bonding with polymer matrices, these fibers are mostly incompatible with biopolymers. The current research endeavor explores the novel eco-friendly oxalic acid (C2H2O4. 2H2O) treatment of sisal fibers (SF) with different concentrations (2, 5, and 8 % (w:v)) and exposure duration (4, 8, and 12 h). Optimum treatment conditions were achieved through the single fiber strength testing of SFs. The tensile strength of the treated fiber with 8 % concentration and 12 h exposure duration (TSF/8/12) increased by approximately 60 % compared to untreated SF. Fourier transform infrared spectroscopy (FTIR), morphological observation, X-ray diffraction (XRD), and thermogravimetric analysis (TGA) of untreated and treated fibers confirmed that TSF/8/12 has better mechanical and crystallinity behavior than its counterparts. The thermal stability and maximum degradation temperature of the TSF/8/12 are 232 degrees C and 357 degrees C. Sustainable composites were fabricated by introducing the treated SFs (30 wt%) as reinforcement in a bio-based poly (butylene succinate) (bio PBS) matrix. The experimental evaluation of mechanical properties, thermal degradation behavior, and water absorption established that treated fiber-reinforced biocomposites (bio PBS/TSF/8/12) have strong interfacial bonding between constituents that resulted in better thermal stability and decreased water uptake than untreated sisal fiber (USF)based composites (bio PBS/USF). The results of the soil degradation confirmed that SFs expedite the rate of degradation of composites due to the increased availability of hydroxyl groups.

期刊论文 2025-03-01 DOI: 10.1016/j.ijbiomac.2025.139507 ISSN: 0141-8130

The study of cellulose-based hydrogels arises from the pressing need for sustainable materials. However, the weak mechanical and biodegradation properties of cellulose hydrogels necessitate the need of other materials to overcome this problem. Therefore, this study aims to enhance the mechanical properties extending the biodegradation period of cellulose hydrogels by using epichlorohydrin (ECH) as a chemical crosslinking agent and garlic extract as an antibacterial material. It was found that a 10% ECH crosslinking concentration provided highest percentage of water absorption which is 656.05%, making the 10% ECH the optimal percentage to combine with garlic extract. At 10%, garlic extract concentration had a greater inhibitory effect on biodegradation with a lowest weight percentage value of 34.27% and high water absorption value exceeding similar to 500%. Therefore, the modified cellulose-based hydrogels can be used in applications involving the water usage and water retention for long-term purposes which is that refers in this experiment to the how long the hydrogel can remain effective in the soil, such as for agricultural applications.

期刊论文 2025-03-01 DOI: 10.17576/jsm-2025-5403-07 ISSN: 0126-6039
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