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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

Phosphogypsum (PG) is produced in large quantities, and its main resource utilization is in the construction sector. This study investigates the feasibility of using PG to manufacture phosphogypsum composite cement-based permeable bricks (PGCPB), focusing on the effects of aggregate size distribution, water-to-binder ratio, and slag powder (SP) content on their mechanical and durability properties and assesses the potential risks related to heavy metal content in PGCPB. The results indicate that the highest 3-day compressive strength of PGCPB is 21.1 MPa at a water-cement ratio of 0.26. The maximum 3-day compressive strength of 25.78 MPa is achieved when the fine-to-coarse aggregate ratio is 3:2. At 14 days, SEM observations reveal that incorporating 20% SP leads to an optimal crystalline microstructure and a denser matrix, corresponding to flexural and compressive strengths of 4.47 MPa and 15.25 MPa, respectively. The 14-day flexural and compressive strengths of the cementing material are 4.47 MPa and 15.25 MPa, respectively, when the SP content is 20%. With an increase in PG proportion, the 28-day compressive strength of PGCPB declines, the water permeability coefficient first rises and then falls, and its frost resistance progressively deteriorates. When PG content is 20-30%, PGCPB meets the JC/T 945-2005 permeability standard and reduces carbon emissions by 22.91% compared to conventional cement-based bricks. Environmental risk assessments confirm that PGCPB poses no risk to either soil ecology or human health, making it a safe and eco-friendly material for pavement applications.

期刊论文 2025-06-18 DOI: 10.1007/s43452-025-01251-1 ISSN: 1644-9665

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

The traditional brick-firing process, characterized by high energy consumption and significant pollutant emissions, poses environmental challenges that require innovative solutions. This research addresses these challenges by reducing natural resource usage, energy consumption, and gas emissions through the production of mudbricks in which 5-10 wt% of the clayey soil is replaced by tea grounds. This approach uses waste products and efficient manufacturing techniques aimed at achieving zero carbon emissions. The meticulous selection and processing of organic waste draws inspiration from ancient practices in which plant residues were used to enhance the durability and performance of building materials. This study demonstrates that the inclusion of 10 wt% tea grounds enhances the workability of the clay by 15 %, as the lignin and hydrogen bonds in the tea rearrange the molecules, hardening the material in a similar way to the starch retrogradation process in bread. These mud- bricks provide a 25 % improvement in thermal insulation compared to standard mudbricks, potentially reducing reliance on energy-intensive heating and cooling systems by up to 20 %. It also show a 30 % enhancement in impermeability relative to mudbricks made without tea grounds, with a 10 % increase in compressive strength.

期刊论文 2025-04-18 DOI: 10.1016/j.conbuildmat.2025.140982 ISSN: 0950-0618

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

This study contributes to the understanding of the vernacular raw-earth heritage of the Champagne region in France, where such structures are currently being documented. The research investigates the mineral composition, grain size distribution, and physico-chemical, mechanical, thermal, and hydric properties of seven adobe types derived from soils with varying compositions (predominantly silicate or limestone-based soils). In particular, the influence of calcite content, which spans a wide range from 0 % to 84.9 %, was examined. The results indicate a strong dependency of peak compressive strength on calcite content: higher CaCO3 levels correspond to lower peak compressive strength. Additionally, the study reveals that the metal oxide content of soils is a critical factor directly associated with mechanical performance. Interestingly, it was observed that historical builders often used weaker adobes for load-bearing purposes and stronger ones for filling, likely without adherence to formal construction standards. Rather than compressive strength, wall design appears to have played a more critical role in structural stability. Regarding thermal properties, calcite content showed minimal influence on diffusivity, specific heat capacity, and thermal conductivity across all adobe samples. Furthermore, all adobes demonstrated excellent to very good moisture regulation performance, with corresponding Moisture Buffer Values varying from 1.65 to 3.09 g/(m2.%RH). The findings of this study underscore the potential of traditional raw-earth techniques in rediscovering and evaluating earthen architecture, with implications for promoting sustainable and environmentally friendly contemporary earthen construction and renovation practices.

期刊论文 2025-04-04 DOI: 10.1016/j.conbuildmat.2025.140582 ISSN: 0950-0618

The clay brick industry is facing significant challenges related to improving its physico-mechanical properties and durability performance of sustainable products. The current study aimed to investigate the effect of stabilizers (lime and cement) on the clay brick properties of three soils. The investigated soils were taken from different regions of Algeria. A series of laboratory experiments were carried out to examine the effect of lime and cement addition with different ratios of 2%, 4%, 6%, 8%, and 10%, on the mechanical properties. The assessment was based on compressive strength, flexural strength, total and capillary water absorption tests. The test results showed that the lime addition to soils A and B led to a significant increase in compressive strength (CS) by 47% and 101%, respectively. The highest values obtained were for the 8% ratio. The obtained gain in compressive strength soil C reached its maximum CS at 6% ratio, and the obtained gain was 44%. However, for cement addition, the highest CS values were obtained at the 10% ratio for all studied soils. The observed gains in compressive strength for soils A, B, and C were 24%, 15%, and 33%, respectively. Flexural strength (FS) followed a similar trend, with lime addition improving (FS) by up to 400% for soil A at an 8% ratio. Cement addition also enhanced (FS), with the highest improvement of 103%, which was observed for soil A at a 10% ratio. It was also observed that lime addition significantly decreased the total absorption by up to 36% at an 8% ratio for soils A and B, and at 6% for soil C. In contrast, the total absorption decreased uniformly with the cement addition up to the 10% ratio. The lowest absorption observed at a 10% ratio was 11.95%. Lime addition also decreased the capillary absorption of clay bricks, and the lowest value was observed at an 8% ratio for both soils (A and B) and 6% for soil C. The CA values decreased by approximately 24% for soils A and B and 14% for soil C. In the case of cement addition, it was noted that the capillary absorption had the same pattern as the total absorption. The percentage decreases in CA were 41%, 40%, and 38% for soils A, B, and C, respectively. These results indicate that the enhancement of clay brick was observed for lime addition ranging from 2% to 8%. Therefore, good mechanical strengths were obtained at a 10% cement ratio.

期刊论文 2025-02-01 DOI: 10.3390/buildings15040631

The rising demand for housing, propelled by population growth, calls for affordable and reliable construction materials. Compressed Stabilized Earth Blocks (CSEB), an environmentally friendly construction material, serves as a potential solution. The clay soil retrieved from the Olifantsfontein Resource Facility, previously unused and occupying valuable space, was repurposed to produce CSEB, aligning with the company's waste reduction commitment. Soil analysis following South African National Standards (SANS) and American Society for Testing and Materials (ASTM) guidelines, revealing poorly graded sand with silt and clay. River sand was chosen based on particle packing theory to achieve a well graded PSD. Three mixtures with varying clay and river sand proportions, while maintaining a constant cement content of 5%, were prepared. Optimum moisture content was determined through trials with different moisture levels. A compressive strength test, both dry and wet, along with a water absorption test, were conducted to evaluate the brick's performance under variable conditions. Results showed that increasing clay content improved compressive strength, classifying the bricks as load-bearing. The study's compressive strength test results ranged between 3-5 MPa, with dry compressive strength outperforming wet compressive strength. On average, the three mixtures exhibited a water absorption of 11.31%, although mix designs with varying clay content showed different average water contents due to the water-absorption properties of cement and the water-holding capacity of clay. Overall, the findings demonstrate the potential of Olifantsfontein clay as a sustainable construction material for meeting the increasing demand for housing.

期刊论文 2025-01-01 DOI: 10.1007/978-3-031-75507-1_56 ISSN: 2211-0844

The earthen construction sector attracts worldwide attention, and earthen bricks are widely used. The conThe earthen construction sector attracts worldwide attention, and earthen bricks are widely used. The construction industry has also progressed in its use of natural green resources such as plant fibers to design building struction industry has also progressed in its use of natural green resources such as plant fibers to design building materials that are both economically and ecologically sustainable. However, the valorization of plant waste in materials that are both economically and ecologically sustainable. However, the valorization of plant waste in construction represents a crucial environmental challenge. The present study focuses on the development and construction represents a crucial environmental challenge. The present study focuses on the development and characterization of a new, low-cost earth-based building material stabilized with cement and corn straw fibers in characterization of a new, low-cost earth-based building material stabilized with cement and corn straw fibers in southeastern Morocco. Different earth bricks stabilized with different cement contents and corn straw fibers were southeastern Morocco. Different earth bricks stabilized with different cement contents and corn straw fibers were developed. The physico-chemical characterization of the soils used in the design of the bricks was carried out, developed. The physico-chemical characterization of the soils used in the design of the bricks was carried out, using physico-chemical, mineralogical and geotechnical characterization, including X-ray diffractometer (XRD) using physico-chemical, mineralogical and geotechnical characterization, including X-ray diffractometer (XRD) analysis, Fourier transform infrared (FTIR) spectra and energy dispersive X-ray (EDX) analysis. The first results analysis, Fourier transform infrared (FTIR) spectra and energy dispersive X-ray (EDX) analysis. The first results reveal that the predominant minerals in oasis soils include ferrous clinochlore, muscovite, calcite and quartz, reveal that the predominant minerals in oasis soils include ferrous clinochlore, muscovite, calcite and quartz, which are mainly composed of silt and sand. Then, the eligibility of these soils for compressed earth brick (CEB) which are mainly composed of silt and sand. Then, the eligibility of these soils for compressed earth brick (CEB) construction was assessed, adhering to established guidelines for the identification of suitable soil types. In construction was assessed, adhering to established guidelines for the identification of suitable soil types. In addition, the thermal properties of the bricks were determined, finding that the use of corn straw fibers improves addition, the thermal properties of the bricks were determined, finding that the use of corn straw fibers improves the thermal performance of the bricks, and cement stabilization leads to an improvement in the bricks' methe thermal performance of the bricks, and cement stabilization leads to an improvement in the bricks' mechanical properties. chanical properties.

期刊论文 2024-12-01 DOI: 10.1016/j.clwas.2024.100160

Olden adobe structures had been commonly built on raw clayey earth hence the technique was exposed to be an eco-green and globally sustainable construction. Nowadays, modern construction materials lack long-lasting stability, affordability, and eco-friendliness. On the other hand, overutilization of earth-based materials led to the depletion of natural resources. So, global construction societies were raised to develop organic construction for an eco-friendly environment. This paper reviewed the recent research on the earthen clay adobe bricks and mortar stabilized with Agro-wastes and how they contended with adaptability and stability standards. The literature study focuses on the ability of the rejuvenated clay adobes rather than the traditional clay adobes of historical times. Agro-waste, non-agro-waste, and some synthetic components were used to enhance the adobe's mechanical, durable, and thermal behavior. This review emphasized altering raw clay and Agro-waste or waste additives by endorsing W/B proportions. From the literature, the scientific interpretations were conferred to attain possible usage of alternate binders and Agro-waste additives with viable W/B ratio. The prime findings of this review were subjected to define modifications of raw clay by adding disposal wastes and alternate binders to resolve the shortage of raw clay resources. Nominal mixing strategies of altered clay bricks are to be prescribed since adobes have no specific standards. The renovations of earthen adobe construction are essential to progress and to satisfy commercial needs as an environmentally sustainable material.

期刊论文 2024-09-01 DOI: 10.1007/s41062-024-01656-6 ISSN: 2364-4176
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