Earth material is environmentally more sustainable than traditional building materials, such as bricks and blocks. The benefits of earth construction are multiple, especially with regard to the ...uniqueness as a way of preserving the artisanship and cultural values of architectural heritage. Unfortunately, construction professionals in the United Kingdom are unfamiliar with many aspects of earthen architecture. A number of interrelated barriers inhibit the acceptance of earth-based material and make it an unpopular choice among construction professionals in the UK. The aim of this study is to develop an understanding of such barriers by identifying and analysing them in light of perceptions held across societies, cultures, and acceptability among professionals. To get to the aim, an interpretivist philosophical stance was taken in this research and a critical analysis of up-to-date literature on various barriers was carried out. The Delphi technique and in-depth interviews were then overseen to substantiate which barriers hindering the acceptability of earth-based material in UK urban construction. A series of interconnected barriers such as, absence of supply chain networks, prejudicial conflict, reticence to changing familiar methods of construction as well as lack of knowledge, skill, and training were identified by experts as the key factors hindering the acceptability of earth-based construction material in the UK.
Earth is not widely used in the UK and a vast majority of local construction professionals are unaware of the potential of contemporary earthen architecture and construction. A number of interrelated ...factors (inhibitors) render earth globally unpopular, and, in the UK in particular, earth is not readily exploited. Certain factors (enablers), no doubt, may increase the acceptance level of earthen construction and technology, and a key aim of this article is to deliver an in-depth investigation and present a clear understanding of how certain enablers may support the widespread acceptance of earth-based material in the context of UK urban housing. In order to achieve this aim, an Interpretivist research philosophy was employed. It comprises a detailed review of the current literature and Delphi method (designed to identify generic enablers that may support acceptance of earth); in-depth interviews employed to validate and contribute to an extensive list of drivers that may promote the widespread acceptance of earth in the background of UK urban housing. A number of interrelated enablers such as offering earth-based material courses in universities, organizing training programmes for all stakeholders, promoting earth building via British media, increased funding on earth construction innovation and exhibiting exemplar earth architecture are found to be the key enablers of acceptance of earth in the UK urban housing. However, this study recommends that implementing all these enablers along with constructing exemplar earth structures in all local areas of the UK would increase public acceptance of earth.
Soils in Saudi Arabia are emerging as potential sustainable building materials, a notion central to this study. The research is crucial for advancing construction practices in arid areas by enhancing ...soil thermal properties through stabilization. Focusing on Hejaz region soils, the study evaluates the impact of stabilizers such as cement, lime, and cement kiln dust (CKD) on their thermal behavior. This investigation, using two specific soil types designated as Soil A and Soil B, varied the concentration of additives from 0% to 15% over a 12-week duration. Employing a TLS-100 for thermal measurements, it was found that Soil A, with a 12.5% cement concentration, showed a significant 164.54% increase in thermal conductivity. When treated with 2.5% lime, Soil A reached a thermal conductivity of 0.555 W/(m·K), whereas Soil B exhibited a 53.00% decrease under similar lime concentration, reflecting diverse soil responses. Notably, a 15% CKD application in Soil A led to an astounding 213.55% rise in thermal conductivity, with Soil B recording an 82.7% increase. The findings emphasize the substantial influence of soil stabilization in improving the thermal characteristics of Hejaz soils, especially with cement and CKD, and, to a varying extent. This study is pivotal in identifying precise, soil-specific stabilization methods in Saudi Arabia’s Hejaz region, essential for developing sustainable engineering applications and optimizing construction materials for better thermal efficiency.
Earth materials have been used in construction as safe, healthy and environmentally sustainable. It is often challenging to develop an optimum soil mix because of the significant variations in soil ...properties from one soil to another. The current study analyzed the soil properties, including the grain size distribution, Atterberg limits, compaction characteristics, etc., using multilinear regression (MLR) and artificial neural networks (ANN). Data collected from previous studies (i.e., 488 cases) for stabilized (with either cement or lime) and unstabilized soils were considered and analyzed. Missing data were estimated by correlations reported in previous studies. Then, different ANNs were designed (trained and validated) using Levenberg-Marquardt (L-M) algorithms. Using the MLR, several models were developed to estimate the compressive strength of both unstabilized and stabilized soils with a Pearson Coefficient of Correlation (R
) equal to 0.2227 and 0.766, respectively. On the other hand, developed ANNs gave a higher value for R
than MLR (with the highest value achieved at 0.9883). Thereafter, an experimental program was carried out to validate the results achieved in this study. Finally, a sensitivity analysis was carried out using the resulting networks to assess the effect of different soil properties on the unconfined compressive strength (UCS). Moreover, suitable recommendations for earth materials mixes were presented.
•Perlite, vermiculite, volcanic scoria, and expanded polystyrene hollow concrete blocks were produced blocks in the field at a commercial scale.•Thermal conductivity of perlite and scoria blocks was ...over 60% lower than that of the commercially made blocks.•Scoria blocks resulted in a 2.4 and 1.15-fold decrease in CO2 emissions compared to conventional and control blocks.
Sustainable development programs focus on reducing traditional energy usage and finding alternative energy sources. Thermal insulation materials can improve energy efficiency and reduce negative environmental impact, and be cost-effective by using low density, strong heat resistance, good thermal conductivity, and durability. Consequently, a novel arrangement of hollow concrete blocks was manufactured on-site in this research. In order to assess the commercial viability of these hollow concrete blocks, four distinct variants (perlite, vermiculite, scoria, and polystyrene) were investigated. Economic viability, fuel energy use, and CO2 emissions were also assessed using experimentally obtained thermal resistance. All the newly produced blocks have fulfilled the compressive strength and absorption criteria set by the standards for non-load-bearing blocks. The perlite and scoria blocks, with their respective lowest dry density of 1544 and 1673 kg/m3, qualified as lightweight concrete blocks. As a result, their thermal conductivity was over 60% lower than that of the commercially made blocks. In addition, the scoria block proved to be the most cost-effective option. When compared to a normal market block, the best scoria wall may enhance the heat resistance by 144%. In terms of the net present value (NPV) for 40 years, this solution cut energy consumption from 272 to 109 $/m2 (about a 150 % reduction). As an additional benefit, constructing a wall out of scoria blocks resulted in a 2.4 and 1.15-fold decrease in CO2 emissions compared to conventional and control blocks. Furthermore, this study emphasizes the potential environmental benefits, such as saving natural resources, energy, and money by using these by-products to make greener concrete masonry units.
Abstract
Earth materials have been used for thousands of years and are considered as one of the oldest construction materials. Recently, due to energy crises and the need to adopt energy-conservative ...solutions in construction sectors, earth buildings have drawn attention worldwide and reemerged since the 1950s. The materials, which are mixtures of natural soils and possible stabilizing materials, are considered as one of the foremost solutions to develop structures that are environmentally friendly due to several properties like low CO2 emission and thermal comfort. Also, the availability of such materials makes them the perfect solution for load-bearing residential house construction and no major processes are required prior to construction. However, understanding the behavior of such materials is challenging due to the large variation in their properties which is attributed to several factors like the sensitivity to water, density, curing conditions, etc. Therefore, in this paper, earth materials (both stabilized and unstabilized) are discussed in different terms including soil suitability, strength, and assessment methods or criterions. The effect of different parameters on the soil performance is analyzed based on previous studies and recommendations are presented, and a number of correlations are prepared based on the data of previous studies. Moreover, the criteria presented by many studies and standards to assess the earth performance are discussed thoroughly. Finally, numerical modeling of such materials is discussed. Such a study is expected to help both engineers and researchers to understand the role of different features on the earth materials and how to utilize them to come up with the optimum performance. Also, the study reveals the lack of development of a classification system that helps in selecting proper materials for earth construction in future.
The practice of designing load-bearing walls with stabilized earth-based material is currently increasing in most developed countries. Potentialities of earth-based materials have room for more ...exploration, investigation, and promotion among building industry stakeholders globally. This research aims to analyze the compressive strength and durability of “Hamrah” Soil to assess its fitness in construction. Such a study is intended to get international and local (Saudi Arabia) construction practitioners’ confidence about soil usage in the construction industry. To achieve this goal, sufficient soil material was procured from the Al-Hofuf region in eastern Saudi Arabia. Several geotechnical experiments were carried out to characterize and identify Hamrah Soil properties. The soil samples were classified in adherence to both the Unified Soil Classification System (USCS) and the American Association of State Highway and Transportation Officials (AASHTO) system. Stabilizing agents (cement and lime) were added at different percentages (0, 2.5, 5, 7.5, 10, 15% of the dry soil weight) to enhance their structural properties. Based on the acceptance criteria of 2 MPa strength, more than 5% cement maximized the stabilized rammed earth (SRE) sample strength more than 2 MPa (up to 6.3 MPa at 15% cement content), whereas 10% lime reached only1.46 MPa, which proved the efficiency of cement stabilization over lime. Micro-characterization techniques utilizing XRD, SEM, and durability tests also lent credence to the effectiveness of cement in the stabilization regime, giving more fibrous formations and a reduction in weight loss below the acceptable limits compared with the case of lime stabilization.
Soil improvement using chemical admixtures has been extensively investigated in the recent past and these admixtures are abundantly being used on various construction projects. However, there is a ...need to elucidate the long-term performance of stabilized geomaterials under aggressive pore fluid environments such as high salinity of groundwater in coastal areas. This study presents the effects of the concentration of pore fluid salinity on the post-stabilization behavior of cement-treated Marl specimens to brine solution from Sabkha deposits and rejected water from a water treatment plant. Unconfined compressive strength (UCS), mineralogy, chemical, and microstructural evaluations have been carried out in this regard. minerals like albite and muscovite completely leached out of the samples after 28 days of soaking in a saline environment. A new mineral Attapulgite was formed at various concentration levels of the pore fluid. Significant changes in the chemical composition were also observed in various phases of the experiments. Moreover, at all salinity levels, the UCS initially increased to a maximum of 75 % which later reduced to a value less than the original strength whereas the elastic modulus (E50) increased as the soaking period progressed. Lastly, it is emphasized that the engineering properties of treated soils exposed to aggressive pore fluids should be carefully assessed for a reliable prediction of the long-term performance of geotechnical structures.
The universal popularity of stabilized earth construction (SEC) with its innovative techniques is growing. Stabilized rammed earth (SRE) and compressed stabilized soil block (CSEB) are the major ...contemporary forms of earth-based material that have now been experimented in Saudi Arabia. However, concrete masonry units (CMU) are more popular than any form of SEC in Saudi Arabia due to the lack of confidence in the structural strength of earth-based material. Therefore, this research was aimed to examine the geotechnical properties, strength, and durability of Al-Hassa stabilized White Soil and to recommend its structural suitability for SEC in Saudi Arabia. Several geotechnical tests, including the grain size distribution, consistency limits, and standard Proctor test, were conducted to characterize and identify the properties of two soil samples collected from different locations in Al-Hassa. Two different stabilizing agents (cement and lime) were used to stabilize the soil at different dosages (i.e., 2.5, 5, 7.5, and 10% of the dry weight of the soil). The performance of the stabilized samples was assessed in terms of both the compressive strength and durability. Al-Hassa White Soil exhibited a strength of more than 2 MPa (up to 5.10 MPa with 10% cement) stabilized with 5% cement, while lower strengths were achieved with lime. The durability of the cement-stabilized soil was assessed using the wet/dry cycles. Soils stabilized with cement exhibited less weight loss than the threshold value recommended by the Portland Cement Association. Finally, the changes in the microstructure of the stabilized soil were observed using X-ray diffraction and the scanning electron microscope.
High plastic soils tend to show poor engineering performance especially low compressive strength, and soil-cement stabilization is one of the most popular practices to enhance their performance. ...However, all clayey soil-cement stabilization may not yield the expected outcome. This research was carried out to determine if the compressive strength and durability improve by adding natural sand while stabilizing Al-Qatif green soil with cement. To achieve this objective, characterization tests were performed to determine the geotechnical properties of the investigated soil. Cement was added to soil samples at various percentages (0%, 2.5%, 5%, 7.5%, and 10% of the dry soil weight) to enhance the soil’s structural properties. The soil sample stabilized with 10% cement and cured for 28 days gained the highest strength of 1.73 MPa, which is below the required 2 MPa. However, when the soil sample was stabilized with 5% cement with the addition of 50% sand and cured for 28 days, it gained strength of 2.89 MPa, which passed the strength criteria. It was observed that the strength gain increased proportionately with the increase of sand content, with 50% sand content yielding the highest strength gain of more than 100% at each tested cement content. The durability of the stabilized soil samples improved, too, as reflected by the significant reduction in weight loss with the increase in cement sand content.
