In recent years, there has been an increased focus on the research of earthen construction, driven by the rising demand for low-cost and sustainable building materials. Numerous studies have investigated the properties of compressed earth blocks (CEBs), however, very few have examined the properties of earth-based mortar. Mortar is an essential component and further investigation is required to enhance the mechanical performance of CEB structures. The study focuses on raw earth mortar (REM), which is a rudimentary mix of water with natural earth consisting of sand, silt and clay. Through experimental investigation, the fresh and hardened properties of three REM mixes were examined to determine the influence of cement stabilisation and jute fibre reinforcement. Shear triplet CEB assemblages were manufactured and tested to determine the initial shear strength of each mortar mix. The addition of 20 mm jute fibre at 0.25 % by weight increased the compressive and flexural strength of cement-stabilised raw earth mortar by 12 % and 20 % respectively. The addition of jute fibre also enhanced the initial shear strength, angle of internal friction and coefficient of friction during shear triplet testing. Finite element analysis (FEA) was undertaken to model the failure mechanism of the CEB assemblages, employing the use of cohesive zone modelling. The results of the FEA provided a satisfactory correspondence to the behaviour observed during experimental analysis and were within +/- 5.0 % of the expected values. The outcome of this investigation demonstrates the potential of REM and contributes to the development of low-cost and sustainable earth construction.

This research examines the influence of blast furnace slag (BFS) on the physico-mechanical properties of compressed earth blocks (CEBs) stabilised with cement and/or lime. A three-factor mixture design is employed to assess the effects of BFS, cement and lime on key properties such as dry density, water content and compressive strength at 28 and 90 days. The study maintains a constant dune sand proportion with soil substitutions up to 20% (420 grams), while the BFS, lime and cement proportions vary with soil substitutions up to 15% (315 g). The findings indicate that mixtures with over 7.5% cement and equal proportions of lime and BFS, as well as a ternary mixture of 10% cement, 2.5% lime and 2.5% BFS, deliver superior strength. Notably, the optimal compressive strength with a high desirability score of 0.93 is achieved using around 14% cement and 1% lime. Proctor curve analysis shows that BFS-cement-lime substitution reduces water content and increases dry density. Statistical analysis confirms the model's robustness in predicting compressive strength, supported by high F-values and low probabilities, and highlights its effectiveness in guiding design decisions. Additionally, the study's evaluation of rupture types offers further insights into material strength and validates adherence to testing standards.

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.

Modern research is focused on the discovery of new compounds that meet the requirements of modern construction. An example of low energy consumption is that buildings consume between 20% and 40% of energy. In this research, the effect of fiber addition on the properties of compacted earth bricks composed of clay and sand and fixed with cement is studied. Fiberglass or palm are used in different proportions (0% and 0.4%). This is done by studying the change in mechanical and thermal properties. The study focuses on clarifying the role of fiber type and the amount of compressive force applied to the soil. To change the properties of bricks. This is studied using experimental methods and systematization criteria. The results showed a decrease in density by 9.1%, with a decrease in water absorption by 8%, an increase in brick hardness by 42.7%, and a decrease in thermal conductivity by 22.2%. These results show that the addition of fiber improves mechanical and thermal properties. Which reduces energy consumption. The results are important because they explain the changes that occur in the earth block when palm fibers and glass are added and how they are used to improve earthen buildings.

Alternative construction materials can allow the modern built environment to abide by sustainability and circularity. This snapshot review highlights some advances made in the stabilization of compressed earth blocks (CEB) using alternative binders in the context of Burkina Faso. The review put forward the considerations of the reactivity and processing of earth materials and binders to produce stabilized CEB. Moreover, it highlights the effects of the changes at chemico-micro-scale of materials to the macro-scale densification, strengthening, and hardening of stabilized CEB. Furthermore, it relates the physical and mechanical properties through the coefficient of structural efficiency and correlates the resistance to surface abrasion with the resistance to bulk compression of stabilized CEB. This could later be extended to the structural efficiency of CEB masonry and allow to easily assess the strength from the quasi-non-destructive test of abrasion.

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.

Conventional practices in earth construction, such as cement stabilization and the energyintensive firing of bricks, contribute significantly to carbon emissions due to the processes involved in cement production and kiln operation. Additionally, concerns over the low strength of earth-based materials have limited their broader applications. This research addresses these challenges by implementing ultra-high pressures (200 MPa and 400 MPa) and bio-binders (animal glue and xanthan gum) to enhance earth materials for construction. Unstabilized earth mixture and normal pressure case (20 MPa) are also included in this study for comparison. A customdesigned mold and a specialized production process are developed to fabricate cylindrical earth samples for testing. After undergoing three hours of consolidation and 28 days of curing, unconfined compressive strengths are measured. Scanning electron microscopy is used to investigate the influence of ultra-high pressures and bio-binders on the microstructures of compressed earth blocks. The experimental results demonstrate that animal-glue- and xanthan-gumstabilized samples under ultra-high pressure achieve compressive strengths comparable to traditional fired bricks, while unstabilized samples exhibit the strength of cement-stabilized rammed earth. This research demonstrates that ultra-compression combined with bio-binder stabilization presents a viable strategy for reducing the carbon footprint of earth construction while significantly enhancing the mechanical properties.

To investigate the impact of relative humidity on the mechanical properties and microscopic pore structure of air lime-stabilized compressed earth, unconfined compression strength (UCS), mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM) tests were conducted by varying the air lime content and relative humidity (RH) in compressed earth. The results revealed three typical failure modes in unconfined compression strength tests of lime-stabilized compressed earth. Both the unconfined compression strength and characteristic parameters of pore structure in lime-stabilized compressed earth exhibited a trend of initial increase, following by a decrease as the air lime content and relative humidity increased. At the microscopic level, the relative humidity and air lime content interacted with the changes in macro-level unconfined compression strength, and the increase of both could promote the lime hydration reactions, inhibiting the crack development. Considering the influence of relative humidity, mechanical performance, and economic benefit improvement, the recommended air lime content for high humidity and low humidity were 0-28% and 0-26%, respectively, offering valuable insights for the optimization and application of lime-stabilized compressed earth as a modern construction material for structural walls.

This paper investigates the effect of integrating Alfa fibers into compressed earth blocks (CEBs) stabilized with varying Portland cement contents. CEB composites were manufactured with earth stabilized using different cement contents (5% and 10% by weight) and Alfa fibers reinforcement (0-0.4% by weight), compressed at 10 MPa with a compaction loading press. After 28 days of drying, the CEBs underwent diverse experimental tests to evaluate their physical, mechanical, and durability properties. The findings indicated that incorporating fibers led to a diminution in unit weight, ultrasonic pulse velocity, and dry compressive strength. Moreover, an increase in water absorption was linked with higher fiber content and less cement stabilizer. Despite the drop in mechanical strength, CEBs with lower cement (5%) and higher fiber content (0.4%) show better thermal performance. Thermal conductivity values were decreased from 0.5166 W/m.K (10% cement without fibers) to 0.3465 W/m.K (5% fibers with 0.4% fibers). The findings show also satisfactory erosion resistance, which could play a crucial role in areas prone to extreme weather events (floods and storms). According to the findings of this research, this material has potential as a promoting composite for the building materials industry.

This comprehensive literature review investigates the impact of stabilization and reinforcement techniques on the mechanical, hygrothermal properties, and durability of adobe and compressed earth blocks (CEBs). Recent advancements in understanding these properties have spurred a burgeoning body of research, prompting a meticulous analysis of 70 journal articles and conference proceedings. The selection criteria focused on key parameters including construction method (block type), incorporation of natural fibers or powders, partial or complete cement replacement, pressing techniques, and block preparation methods (adobe or CEB). The findings unearth several significant trends. Foremost, there is a prevailing interest in utilizing waste materials, such as plant matter, construction and demolition waste, and mining by-products, to fortify or stabilize earth blocks. Additionally, the incorporation of natural fibers manifests in a discernible reduction in crack size attributable to shrinkage, accompanied by enhancements in durability, mechanical strength, and thermal resistance. Moreover, this review underscores the imperative of methodological coherence among researchers to facilitate scalable and transposable results. Challenges emerge from the variability in base soil granulometry and disparate research standards, necessitating concerted efforts to harness findings effectively. Furthermore, this review illuminates a gap in complete lifecycle analyses of earthen structures, underscoring the critical necessity for further research to address this shortfall. It emphasizes the urgent need for deeper exploration of properties and sustainability indicators, recognizing the inherent potential and enduring relevance of earthen materials in fostering sustainable development. This synthesis significantly contributes to the advancement of knowledge in the field and underscores the continued importance of earth-based construction methodologies in contemporary sustainable practices.