Adobe Blocks Research Articles

Effect of the coconut fibers and cement on the physico-mechanical and thermal properties of adobe blocks

This work aimed to investigate the effect of cement and coconut fibers on the thermal and physico-mechanical characteristics of adobe blocks. Thus, a clayey raw material consisting of kaolinite (62 wt%), quartz (31 wt%), goethite (2 wt%) with a plasticity index of 21.5 % was used to manufacture adobe blocks amended with cement and coconut fibers. First the adobe blocks were formulated with an optimal cement content of 4 wt% before adding coconut fibers up to 1 wt%. The physico-mechanical and thermal characteristics of manufactured composites were then studied. According to the results obtained, the incorporation of coconut fibers into the clay-cement matrix decreases the apparent density and volume shrinkage and increases the porosity of the adobe blocks. The presence of coconut fibers in adobe blocks promotes the phenomenon of water absorption. The combined effect of the formation of calcium silicate hydrate (CSH) and hydrogen bonds between fibers molecules and those of clayey minerals leads to an improvement in the mechanical properties of adobe blocks. The thermal conductivity of adobe blocks decreases with the fiber content due to the presence of pores and cellulose molecules in the fibers which have an insulating nature. Taking into account their physico-mechanical and thermal properties, adobe blocks containing 0.6 wt% coconut fibers and 4 wt% cement are suitable for building sustainable habitats and thermally comfortable.

Adobe Blocks Reinforced with Vegetal Fibres: Mechanical and Thermal Characterisation

The present study is based on the characterisation of adobe blocks of the central region of Portugal. It is recognised that the safeguarding of the existing building stock of constructions in the traditional adobe construction technique, through different levels interventions, should also preserve the historical and cultural identity of the area as well as the traditional construction techniques, starting from the ground itself. Soil, as a repository of valuable information on the history of the site, underpins the conservation and preservation process. However, the soil is a local expression of the site, and a precise knowledge of its characteristics is necessary to hypothesise building recovery strategies. For this reason, the characteristics of adobe blocks from old buildings in the village of Torres in Anadia, in a rural area that has not yet been the subject of scientific research, were evaluated. These adobe blocks were taken from the buildings to be used in the laboratory to determine the similar mixing rates for the new adobe mixtures by analysing the material’s chemical, physical, mechanical, and thermal properties, as well as its particle size distribution. In the study area, a wetland was identified characterised by a notable presence of vegetation, namely bunho and junco (Schoenoplectus lacustris L.). These fibres, which can be assimilated to Typha, are wild aquatic plants that can impair the biodiversity of wetlands but which, used as reinforcement for the production of adobe bricks, can stimulate new, more sustainable forms of economy in in the area, which is classified as rural. The fibres were divided into two groups of 10–30 mm and 30–60 mm in length, and compositions with an additional 1 to 3% of fibres were formulated. This experimental approach was useful for understanding how the length and quantity of these fibres influence the performance of the material, thus contributing to improving knowledge about the behaviour of adobe blocks in relation to the incorporation of vegetable fibre reinforcement. The research findings reveal that the length of the fibres and percentage of incorporation have a significant impact on the mechanical behavior of the material, particularly in relation to its compressive strength up to 50%. The tested formulations were also assessed with respect to capillarity, for which most of the formulations were classified as weakly capillary, with a capillary index (Cb) of less than 20. With respect to thermal conductivity, the incorporation of fibres led to a reduction of up to 20%. The characterisations demonstrate that the optimisation of adobe is the initial stage in attaining comprehensive insight into the heritage of traditional construction in the central region of Portugal, with a particular focus on the village of Torres and the ancient adobe construction technique.

Study on seismic failure mechanism and damage model of unconstrained adobe block walls

Through the quasi-static cyclic in-plane loading test of three kinds of unconstrained adobe block walls, namely plain adobe wall, modified mud adobe wall and modified adobe wall, the failure mode and seismic performance of each specimen were clarified. Using residual deformation and cumulative energy dissipation as failure parameters, a two-parameter seismic damage model of unconstrained adobe block walls was established. and a calculation method for the adjustment coefficients of energy consumption items was provided. The results showed that the failure mode of the typical unconstrained adobe block wall under earthquake action was not affected by the modification of adobe materials, and the final failure mode was shear failure along the mud crack and the inclined crack extending through the block. Furthermore, the proposed seismic damage model can well reflect the evolution law of earthquake damage of adobe block walls, and the recommended damage index boundary values for five performance levels were given, providing a reference for performance-based seismic design and damage assessment of adobe block walls.

Implications of agro-industrial wastes on the durability and erosion characteristics of unfired soil-blocks reinforced with paddy straw fibers: Sustainable earth construction

On Earth, there is an abundance of soil that has been utilized to build homes for millions of people. Manufacturing compacted stabilized adobe blocks requires adequate water added to the appropriate soil type that has been admixed with binders and fibers to attain maximum density. The mixture is then compressed using the appropriate adobe-forming machine. Currently, the major environmental and human health risks worldwide come from industrial and agricultural wastes because of disposal concerns. The production and use of cement and cement blocks bring numerous economic and environmental issues. Utilizing locally available resources and enhancing standard production and testing methods are two feasible options for sustainable growth. Researchers have seen the promise of earthen construction as an alternative building material, and it is becoming more popular in the context of sustainable development. Marble dust (MD) (Industrial waste), sugarcane bagasse ash (SBA), and paddy straw fiber (PSF) (Agricultural wastes) were utilized in this research to manufacture the unfired admixed soil blocks. This study utilizes marble dust composed up to 25%–35%, paddy straw fiber constituted 0.8%–1.2%, and bagasse ash made up 7.5%–12.5% of the soil. The marble-dust-bagasse-ash-soil mix was strongly adherent to PSF, according to SEM investigation. In addition, as is apparent from the image, the number of pores is insignificant. These images support the preceding conclusions regarding this sample’s increased flexural and tensile strength. The primary constituents discovered on the surface of an unfired ad-mixed soil block strengthened with PSF of length 75 mm were silica (Si) and oxygen (O), according to the EDS examination. Aluminum (Al) and magnesium (Mg) were found in trace amounts. The endurance characteristics of the block were determined by conducting different tests on the eighty-one (81) design mixes of the produced unfired ad-mixed adobe blocks, followed by modeling, optimization and microstructural analysis. The results show that the recommended technique improves the durability characteristics of admixed soil blocks without burning better than burnt bricks.

Shaking table tests on single-bay timber-framed wall specimens with fired brick and adobe block infills and mortise-tenon joints

In-plane uniaxial shaking table tests were carried out on full-scale single-bay timber-framed masonry wall specimens characteristic of Ottoman-period mansions in mainland Greece. The posts were connected to the sill-beam with cylindrical mortise-tenon joints. Two infills were investigated: solid fired clay bricks with lime-cement mortar and adobe blocks with earth mortar. Both specimens proved able to withstand significant base accelerations up to 1.0 g with little damage, exhibiting rocking behavior, with the post tenons lifting up from the mortises due to exceedance of friction at the contact surfaces. The earth material specimen presented higher uplift, top displacement and acceleration. A short comparison with static monotonic and cyclic tests is also presented.

ADOBE WITH TERMITE MOUND SOIL FOR SUSTAINABLE HOUSE CONSTRUCTION IN GAMBELLA

The Gambella community in Ethiopia uses their indigenous knowledge of mixing termite mounds soil with locally available straws to build their mud houses. Mud houses constructed with termite mounds are comparatively stronger than those prepared with other soils, but they have severe durability issues due to shrinkage cracks that necessitate regular maintenance which is not affordable by many. This research paper presents technology intervention to resolve these issues faced by the community by introducing an alternative method of house construction called adobe. As part of this research 144 blocks of adobes were cast by using locally available materials and their performance was evaluated by conducting several strength and durability tests. The experimental results revealed that adobe prepared with termite mounds soil, 1.5% straws, and 2.5% of binder provides excellent strength and durability. The compressive strength was measured to be 2.6 MPa. Enhanced durability in terms of reduced shrinkage (17%), a low initial rate of absorption (0.29), and water absorption (0.26) were found in the adobe blocks. This indicates adobe is certainly the best solution to the existing houses' durability issues and a best-class sustainable solution for the construction of houses in Gambella, Ethiopia. Keywords: Adobe, Mud Houses, Compressive strength, Durability, Straw, Chikka Bets

Modeling Earthen Treatments for Climate Change Effects

Adobe has been used globally for millennia. In the US Southwest, cultural heritage sites made of adobe materials have lasted hundreds of years in an arid/semi-arid environment. A common prediction across multiple climate change models, however, is that rainfall intensity will increase in the US Southwest. This increased erosivity threatens the long-term protection and preservation of these sites, and thus resource managers are faced with selecting effective conservation practices. For this reason, modeling tools are needed to predict climate change impacts and plan for adaptation strategies. Many existing strategies, including patching damaged areas, building protective caps and shelter coating walls are already commonly utilized. In this study, we modeled adobe block construction, subjected extant walls to a local 100-year return interval rainfall intensity, and tested earthen-coat-based strategies to minimize the deterioration of earthen fabric. Findings from the resultant linear models indicate that the patching of earthen architecture alone will not prevent substantial damage, while un-amended encapsulation coats and caps provide similar, and significantly greater protection than patching. The use of this model will enable local heritage resource managers to better target preservation methods for a return on investment of the material and labor costs, resulting in better preservation overall and the retention of culturally valuable resources.

Evaluation of the Properties of Adobe Blocks with Clay and Manure

The development of new building materials that meet technological, economic, and environmental criteria has been highlighted in recent decades, especially regarding the use of alternative raw materials or new production methodologies. In this context, the objective of this project was to promote the development of adobe blocks using clay and manure, contributing to the sustainable development of the construction sector due to the use of adobe blocks, produced by the raw earth technique. Initially, the raw materials were characterized through chemical composition by XRF, mineralogical composition by XRD, granulometry, and Atterberg limits. Later, adobe blocks were produced manually, measuring 20 × 10 × 8 cm3, using three dosing techniques: (i) blocks with clay and manure; (ii) blocks with clay, sand and manure; and (iii) blocks stabilized by Portland cement and hydrated lime. The tests evaluated were compressive strength, water absorption, and durability. The characterization results of the raw materials show that the material used in the research are suitable for production of adobe blocks. The mechanical parameters prove a disadvantage of adobe blocks: their low resistance. Even so, the results with the use of adobe improve the strength of the material, due to the solidification of the adobe structure. In addition, the use of stabilization, mainly Portland cement, allows the results obtained in the research to be compatible with other published articles. Thus, it is concluded that the use of manure and stabilization, such as Portland cement, improve the mechanical behavior and stability of the blocks, which increases the durability of the material.

Analysis of Energy Efficient Features in Traditional Hill Architecture of Himachal Pradesh, India for its Indoor Performance in Sub-Tropical Climate

Vernacular architecture of any region highlights the architecture and construction methods developed by the locals, in need to provide indoor thermal comfort amidst outdoor climatic conditions which is done using the locally available materials and construction techniques in response to the climatic conditions and geographic location. At present in India, standardized building materials and construction methods are adopted for modern buildings due to the easy availability of materials and also serving well economically. This paper presents the results of a field study and simulations to investigate the thermal and energy performance of selected case study, two traditional houses using adobe blocks, rammed earth and stone construction are compared to a modern house using a masonry envelope, the construction material is altered by adding insulation to the building envelope to study the differences in the performance of original construction. The case study is located in Dharamshala town in the upper reaches of Kangra valley, Himachal Pradesh, India having a sub-tropical humid climatic condition. Hourly indoor temperatures of the houses were monitored and a field survey was done to collect the data, and simulations were carried using dynamic thermal simulation software DesignBuilder, the monitored data was then used to match the parameters in simulation models. The results show that indoor temperatures of traditional mud house provide better thermal comfort when compared to modern house, however, slightly high energy demand in traditional house is observed due to increase in discomfort hours.

The Compressive Strength of Adobe Block Masonry Walls

Masonry is a composite material that is fabricated using natural and/ or artificial units that are joined together with mortar. The natural units include stone amongst others, while the artificial includes bricks and blocks that could be made out of concrete or fired clay products as well as adobe (stabilised or unsterilized). The wide spectrum of the units used in masonry wall fabrication demands that appropriate tests should be conducted to determine their compressive strength and by extension the effectiveness of the wall masonry in performing its inherent architectural design functions of the building such as environmental protection of its inhabitants. An experiment was conducted (i) to determine the structural suitability of stabilised adobe block masonry under uniform and concentrated loading and (ii) to determine adobe block masonry design guidelines. All block units for the test masonry were fabricated using the appropriate Portland cement: sand mix of 1: 11 identified using mix trials for the adobe block categories that were greater than 11.1 N/mm2. The concrete mix was prepared using a concrete mixer and moulded. Moulding was conducted using modified standard 6-inch adobe block mould that led to a 300 mm x 150 mm x 100 mm block. The blocks were cured for seven days under polythene sheets. There were two sets of masonry tests running in parallel; (1) the compressive strengths of the simulated stabilised adobe block masonry under uniformly distributed loads (prism tests) with three different mortar regimes; weak (1:8), medium (1:5) and strongest (1:3) and (2) masonry characteristic compressive strengths under concentrated loads (wall tests) using only the medium mortar mix (1:5). Prism specimens (300 mm x 150 mm x 460 mm) and wall specimen (920 mm x 150 mm x 460 mm) had three replications and cured under laboratory ambient environment conditions for 28 days prior to testing. Test specimens were subjected to compression under uniaxial uniformly distributed loads applied vertically and continuously at a rate of 1 N/mm2/minute to failure. There were 3 wall tests running parallel for each of the 4 block Portland cement proportions at the 1:5 mortar mixes. Data were analysed using MS Excel featuring descriptive statistics. Confidence intervals (95%) using the Student t-test were used to compare variations between and within specimens. Vertical deformations and time to failure were analysed using video tapes through Daub 2.0, video editing free download software. The results indicated that with the prism tests the increase in Portland cement masonry block proportion from 5% - 15% (3.0 N/mm2 - 15.4 N/mm2) significantly increased the masonry characteristic compressive strength at all mortar compressive strengths. However, the masonry characteristic compressive strengths were significantly less than that of the corresponding block. This trend was similar to the wall tests. At high block and low mortar compressive strengths, prism failure was initially by vertical tensile cracking through the mortar followed by the block, whereas at high masonry block and mortar strengths, failure was sudden and typically manifested by initial vertical tensile cracking and eventually side splitting of the block and mortar.Wall failure at low concentrated loads, was initially manifested by vertical cracks along the joint directly below the load point, and at its edges on both sides of the wall. The proposed design guidelines for stabilised adobe block masonry included mortar designations (a), (b) and (c) with masonry mortar proportions by volume (cement: sand) of 1:3, 1:5, and 1:8, respectively, under uniform and concentrated loads were proposed for use in adobe block masonry for agricultural structures.

Adobe mixtures reinforced with fibrillated polypropylene fibers: Physical/mechanical/fracture/durability performance and its limits due to fiber clustering

This study assesses the feasibility of the incorporation of fibrillated polypropylene fibers (FPFs), an engineered multidimensional and multifilament fiber mostly used to reinforce concrete mixtures, into adobe mixtures (AMs), a traditional and manually-made material used to produce adobe blocks. The incorporation of FPFs was assessed using increasing dosages (0%, 0.25%, 0.5%, and 1% in wt% of clay soil) of FPFs. These fibers were gradually added and mixed with the clayey soil prior to incorporation of water to promote uniform mixtures with adequate fiber distribution to reduce the formation of fiber clusters. The impact of FPFs was evaluated in terms of its effects on the bulk density (physical), compressive and flexural strength (mechanical), flexural toughness indices (fracture) and water erosion resistance (durability) of AMs. Results indicate that increasing dosages of FPFs monotonically reduce average values of bulk density, as well as compressive and flexural strength of AMs. On the other hand, these increasing dosages of FPFs monotonically increase average values of water erosion resistance as well as flexural toughness indices, varying the flexural failure mode from brittle (unreinforced AM) to ductile (reinforced AMs) because of the adequate bonding and FPF-bridging effect after the crack generation as confirmed by instrumentation as well as digital image correlation evaluations implemented in this study. The significant reductions of bulk densities and compressive and flexural strengths obtained for fiber-reinforced AMs were related to the increasing number of fiber clusters found for increasing dosages of FPFs within the fiber-reinforced mixtures, which was evaluated using scanning electron microscopy analyses. For example, positively the AM incorporating 1% of FPFs increased, on average, the flexural toughness by 674% and reduced the bulk density and water erosion depth by, on average, 9% and 64%, respectively, when compared to the unreinforced AM. However, this large dosage of FPFs also generated a significant reduction of the compressive strength (60% on average) and the flexural strength (43% on average) when compared to the plain mixture. On the other hand, a small dosage of FPFs (0.25%) generated less significant improvements in terms of flexural toughness, bulk density, and water erosion (on average, increment of 58% and reductions of 2% and of 38%, respectively, when compared to the unreinforced AM). Yet, the latter mixture presented reductions, on average, of compressive and flexural strengths of 24% and 16%, respectively, when compared to the plain mixture, and these reductions were significantly smaller than the reductions obtained by the largest FPF dosage, due to the significantly smaller number of fiber clusters presented by the 0.25% dosage when compared to the 1% dosage. Finally, the mechanical performance limitations exhibited by the incorporation of FPFs, especially in large dosages, are related to generated fiber clusters due to the inherent morphology of these FPFs as well as the traditional manual confection process of AMs. Therefore, this study recommends the implementation of FPFs in AMs, but in small dosages and/or suggests the implementation of a mechanical mixing/compaction process that guarantee a more uniform fiber distribution that reduces the generation of fiber clusters.

A New Mixture Criterion for the Improvement of the Compressive Strength of Adobe Using Zeolite as Stabilizer

The use of zeolite as a stabilizer for adobe has proven to have the ability to improve its physical and chemical properties. This is shown in the positive results in terms of strength gain and water absorption resistance in adobe blocks. In this work, an investigation was carried out to evaluate the use of zeolite as adobe stabilizer. The adobes were made with two different types of soil with different content of zeolite (5, 10, 15, 20% by weight) maintaining the zeolite-lime ratio 1:1. The samples were tested on compressive strength and water absorption. The deterioration of the adobes was analyzed under conditions of extreme humidity. The results of this study revealed that adobe behavior is influenced by the synergistic relationship between soil, zeolite and lime, showing significant changes in compressive strength even under extreme humidity conditions. It was also observed that the chemical composition of the soil influenced the development of the pozzolanic reaction. The stabilization of adobes with 15% of zeolite showed the best mechanical behavior, before and after deterioration assay. Hence, zeolite promises to be a good alternative as a stabilizer in adobe construction systems.

Addition of Sawdust and Polystyrene in the Elaboration of Adobe Blocks for Single-Family Homes and its Effect on Temperature Variation and Acoustic Conditioning in Ambato, Tungurahua

This experiment evaluates the use of sawdust and expanded polystyrene (EPS) in the elaboration of adobe blocks as thermal and acoustic constructive elements with low environmental impact. To begin with, a soil selection and analysis process were carried out based on E-080 standard, then traditional adobe blocks with a percentage of 5%, 10% and 15% of sawdust and EPS were added in each mix. A suitable chamber was built to carry out the tests, based on specific standards, the chamber was divided into two rooms by a wall of the abode block with the addition of sawdust and expanded polystyrene using a 5mm layer of mortar to correct joint errors, this was considered appropriate for making temperature and sound measurements with the SPARK LXi Data logger (PS-3600A). Based on the Ecuadorian Construction Standard, comfortable reference values were determined for the measurements. After 28-day elaboration, the blocks were tested under compression. This test showed that all the analyzed samples exceeded the minimum resistance of 1MPa established in the E-080 standard. It was the highest compressive strength obtained in blocks with 5% of sawdust and EPS with a maximum resistance of 2.66 MPa. In addition, it was obtained that the wall made of 10% and 15% of adobe sawdust and EPS present the best performance to thermal variation and acoustic conditioning based on the standards NCh 352, NCh 851 - NCh 849 and NCh 2865.

Effectiveness of Salty Sand in Improving the Adobe’s Thermomechanical Properties: Adrar Case Study (South Algeria)

Adobe constructions have always existed, particularly in the Sahara’s dry and scorching regions. This material has a high thermal inertia and can protect buildings from inclement weather. Its mechanical resistance, on the other hand, is still low and has to be increased. The current research, thus, investigated the effect of sand salinity on the thermal and mechanical properties of adobe. The sand needed to create adobe blocks was purchased from 2 distinct locations. The first one was normal sand while the other one was salty sand rich in SO4- sulfate. We considered different ratios of each sand from 10, 20 up to 90 %. The results showed that the adobe made from the sulfate-containing sand improved the compressive strength by about 36 % from 1.91 to 2.58 MPa, and flexural strength by about 71 %, from 0.35 to 0.60 MPa, and reduced the thermal conductivity by 14 % from 0.86 to 0.72 w/mk. HIGHLIGHTS Improving the compressive strength by about 36 % Improving the flexural strength by about 71 % Improving its thermal behaviour and inertia by about 3 % Testing more of 90 samples Studying two different locations Analyse Mineral and physical Analyse of clay and sands from the arid zone GRAPHICAL ABSTRACT

Characterization of Adobe Blocks: Point-Load Assessment as a Complementary Study of Damaged Buildings and Samples

Adobe masonry is one of the oldest construction systems still in use today, Mexico has an enormous cultural heritage with traditional adobe houses being very representative of the rural communities and their culture. The 2017 Puebla Earthquake on September 19th struck the country causing the loss, destruction, and damage of historic buildings in several Mexican states, with the traditional earthen dwellings being the most vulnerable structures to these events. The fast abandonment of the local materials and techniques entails further research regarding the characterization of these construction systems, therefore, reconstruction efforts first require the recovery of the construction technique. After the seismic events, adobe samples of the remaining adobe structures of Jojutla de Juarez were collected. This population was one of the most affected in all the country, and, because of the major losses suffered, the study was conducted to determine the material properties of the dwellings’ adobe shards and natural quarry clays of the region. The characterization included destructive and non-destructive tests, mineralogical and granulometry analyses, and composition of the adobe samples of the buildings, as well as the aggregates. As a novelty, the compressive strength of the pieces was tested by two methods: the traditional compression strength test and the point-load test, in order to obtain the indicative values and the correlation equations between both tests. From the formal analysis and the laboratory, it was observed that the adobes from Jojutla presented different compositions which combined with the building malpractices and alterations to the traditional systems caused unpredictable behavior during the earthquake. The conduction of point-load tests in situ, as a part of a complete characterization methodology, could be an alternative to study the mechanical properties of patrimonial or damaged building samples before its disappearance.

Finite element analysis of single-storey unreinforced alternative masonry walls

The most commonly cited obstacles to the uptake of alternative masonry units on a meaningful scale, despite significant research investment, are a lack of standards and understanding of their structural behaviour. This paper contributes to the body of knowledge on finite element analysis of alternative masonry structures, towards improved understanding of their structural behaviour. Two critical masonry wall configurations, in the context of South African low-income, government-subsidised housing, are analysed using the simplified micro-modelling approach, under ultimate limit state wind and seismic actions. Three alternative masonry materials are characterised and employed in the numerical analyses, geopolymer, compressed-stabilised earth and adobe blocks, as well as conventional concrete blocks as benchmark. Despite the wide spectrum in masonry materials analysed, the chosen modelling approach captured the major failure mechanisms well. The four materials performed as expected relative to one another, but most wall/material configurations failed to resist the required design load, including the conventional concrete masonry material.

Numerical investigation of optimal wall materials for effective thermal performance in warm and hot climatic regions

Purpose Heat gain in buildings occurs due to heat transfer through the building fabric or envelope, especially the walls and roof. The purpose of this paper is to identify and recommend the suitable wall materials for better thermal performance in buildings in warm and hot climatic zones of India. As India lies between the tropic of cancer and the equator, the solar radiation from the sun falls more on the walls than the roofs of the buildings. Thus, it is imperative to protect the walls from heat gain to promote thermal comfort in naturally ventilated buildings and reduce the energy loads due to artificial cooling systems in air-conditioned buildings. Design/methodology/approach In this paper, an investigation of heat flow characteristics in steady-state and the transient state for five different uninsulated wall structures using computational fluid dynamics (CFD) software has been carried out. The climate conditions at Madurai, India have been considered for this study. Findings The findings of the study revealed that aerated autoclaved concrete (AAC) and hollow clay blocks (HCB) for external walls in naturally ventilated buildings in warm climatic regions could improve the building’s thermal performance index and reduce peak indoor operative temperature by about 6°C–7°C. The results of steady-state and transient state analysis were found to be in good agreement with the results of the reviewed literature. Research limitations/implications Over the past few decades, only very few architects and builders have been successful in influencing their clients to accept alternate materials such as AAC blocks, HCB, stabilized earth blocks, adobe blocks, fly-ash bricks as an alternate to conventional bricks in an attempt of highlighting their benefits, such as; materials that are easily available, more energy-efficient, can withstand the extreme weather conditions, promote thermal comfort and cost-effective. This paper provides strong evidence that AAC and HCB blocks are the most appropriate materials for improving the thermal performance of envelope walls in regions where the outdoor temperatures are above 40°C. Originality/value This paper has made an attempt to identify the appropriate wall materials for effective thermal performance in warm and hot climates. A comparative analysis between five different wall types under the existing solar conditions has been analyzed using CFD simulation study in steady-state and transient conditions under summer conditions and the appropriate wall materials have been suggested. There has been no attempt carried out so far to analyze the thermal performance of different walls using 24 h transient approach in CFD.

Adobe blocks reinforced with natural fibres: A review

Global warming is being a major threat to all living organism affecting climate change, sea level etc., scientist focus on innovations that are eco-friendly and sustainable. In the growing concern of awareness regarding sustainable building material and environmental issues. Adobe blocks top in the study of eco-friendly materials because of the significant benefits like sustaining indoor air quality, indoor temperature maintenance, and its low environmental repercussions. Though the blocks are often used in rural areas of developing countries for ages now, research on this field has blossomed latterly as it has some limitations in terms of strength and durability properties. In this review, plant fibre fused blocks are studied to understand the influence of the fibres in adobe block properties. This review paper is based on twenty-fivemajor investigations which includes the characterization of natural fibre along with their cellulose content, and the tables of material compositions, and the mechanical, hygrothermal properties and the durability performance of earth matrix. The study also highlighted the significance of analysing the properties of the fibre to be fused and reported the lack of testing in durability criteria like abrasion, life expectancy, fire resistance etc., Developing adobe blocks will help in many environmental perspectives especially in terms of global warming and climate change and can also help in achieving minimal energy and resource utilization.

CONTRIBUTION TO THE STUDY OF AN ECO-MATERIAL BASED ON EARTH STABILIZED BY VEGETABLE FIBERS AND ALOE-VÉRA JUICE

This study falls within the framework of sustainable development, and is mainly interested in the renovation of the mileage technique formerly used by our ancestors, which is the Adobe. This durable and vulnerable material is a very interesting aspect to treat. In this context, a contribution for the study of an eco-material has been proposed. This is the land use stabilsee by adding vegetable fiber and the juice of aloe vera for making adobe block as eco-material more efficient and sustainable. Several properties are studied and the results have shown the important advantage of adding aloe-vera as a stabilization technique and the addition of fiber to the physico-mechanical and the durability of the earth material (Adobe).

Mechanical and damage similarities of adobe blocks reinforced with natural and industrial fibres

Adobe is an earthen-based material that consists of the use of a clayey soil and, most of the times, straw fibres to manufacture blocks that are afterwards sundried. This study reviews the use of three types of fibres: vegetal, industrial and animal, for the manufacture of adobe blocks. Overall, all the fibres increase at least one order of magnitude the impact strength of plain adobe blocks and reduced the shrinkage cracking of adobe plasters in at least 50% with respect to plain adobe. Compressive and flexural strength average values were not increased nor decreased by the addition of fibres. The intrinsic variability of the mechanical properties of plain adobe persists with any of the fibres tested in this study. Based on the findings of this study, we recommend using jute fibres with a dosage of 0.5% and a length of 30 mm. Keywords: Crack control, natural fibres, industrial fibres, adobe blocks, impact strength