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Sustainability in the materials we use for construction is a prime concern, focusing on reducing the embodied energy and carbon footprints of the materials used. The cement used in concrete products is responsible for a significant proportion of Man's CO2 emissions and its production requires substantial energy input, as do fired clay products. For...
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... there were few but wide-ranging specifications, the more conservative value was selected (as in unsupported wall length) or an average value (as in distance from corner of building to opening). The specifications selected are shown in Table 5 with justification for the selected values also given. ...Context 2
... the specifications given in Table 4, a set of building plans were developed for an earthquake resistant rammed earth house. Exploded view, floor plan and an isometric view have been produced using the information from Table 5 as shown in Figure 3. According to Eurocode 8 [65] a number of aspects need to be considered at the conceptual design stage of a building in order for it to meet two key requirements for building in seismic zones, i.e. no collapse and damage limitation performance levels are attained. ...Context 3
... overall floor area for this building will be 36.9m 2 . Additional rooms can be added as long as buttresses and overall wall lengths do not exceed the dimensions specified in Table 5. A reinforced concrete horizontal band will then be cast on top of the wall tying the foundation, plinth beam, rammed earth walls and horizontal band together using the vertical reinforcement bars. ...Citations
... Earth is an ancient building material that, in recent years, has attracted the interest of both the scientific community and construction industry because of its low environmental footprint compared to conventional alternatives, such as concrete or fired bricks [MINKE, 2000;MOREL et al., 2001;LIT-TLE and MORTON, 2001;ARRIGONI et al., 2017;BRU-NO et al., 2017a, b;BECKETT et al., 2017;VYNCKE et al., 2018;ANYSZ and NARLOCH, 2019;NGUYEN et al., 2019;COCCO et al., 2022;TAN et al., 2022;THOMPSON et al., 2022;LOSINI et al., 2023a;PARDO, 2023]. To date, the major issues associated to earth materials are: a) their poor durability when exposed to rainfall infiltration or capillary rise and b) the absence of well-established methods to estimate their hygrothermal inertia [AL-LINSON and HALL, 2010;PACHECO-TORGAL AND JALALI, 2012;MCGREGOR et al., 2016;MEDJELEKH et al., 2017;SOUDANI et al., 2017;BRUNO et al., 2020;FABBRI et al., 2022;LALICATA et al., 2023c, d]. ...
Raw earth is emerging as a viable building material with a lower carbon footprint than conventional concrete and fired bricks. Raw earth is an excellent passive hygrothermal regulator, which improves occupants' comfort while reducing the need for active heating/cooling. Modelling the coupled hygrothermal behaviour of earthen materials is however highly complex and requires the introduction of some simplifying assumptions. The degree of hygrothermal coupling depends on the chosen equations of moisture and heat transfer including the specific forms of the water/ vapour permeability functions and retention law. The influence of these assumptions is here investigated via a simple one-dimensional transfer model, which simulates the behaviour of an earth wall subjected to time-dependent cycles of temperature and relative humidity on the two faces. Results show that the complexity of the governing equations can be greatly reduced by neglecting the variations of vapour mass and the dependency of suction on temperature without losing accuracy. In addition, the moisture buffering capacity of the material strongly depends on the liquid permeability which, in turn, is a function of both saturated permeability and water retention properties.
... In the realm of civil engineering, the quest for materials that can enhance the structural integrity of buildings, especially in seismically active zones, is of paramount importance [1,2]. One such material that has gathered significant attention is the lightweight aggregate. ...
This study aimed to predict the split tensile strength (STS) of lightweight concrete having silica fume (SF) as supplementary cementitious material (SCM) under
thermal stresses. Machine learning (ML) models including a conventional machine learning (CML) model as Artificial Neural Networks (ANN) and ensemble machine
learning (EML) models, particularly Random Forest (RF) and Gradient Boosting (GB) were developed to predict the STS. Dataset comprising of 96 instances was
splitted into 80% for training and 20% for testing phase respectively. With the help of the 80% training data and subsequent hyperparameter tuning, various CML and
EML models were developed. ML models were analysed statistically for both the training and testing phases, under the model performance parameters, line diagrams,
and Taylor diagrams. After the thorough statistical analysis, it was concluded that the GB as an EML model outperformed all other ML models. This was demonstrated
by the fact that it had constantly higher model performance parameter values of RMSE, MAE and R2 as 0.151, 0.115 and 0.977 for training and 0.23, 0.196 and 0.908
for testing respectively. Also, from the line diagrams which shows a good correlation with the actual and predicted STS values and from the Taylor diagram of the
various ML models for both the phases, it was concluded that the GB model is found superior model for this specific study.
... Furthermore, susceptibility to climatic parameters, including humidity and solar radiation, introduces internal variations in the material, thereby compromising its structural performance. Additionally, the fragile nature of this construction type poses a considerable risk, particularly during seismic events, potentially leading to structural weakening or even imminent collapse [3][4][5]. ...
... Structures built with earthen building techniques, such as adobe, cob, and rammed earth, represent 15% of the sites on the World Heritage List (Arto et al. 2020;Saidi et al. 2018). In addition, many earthen houses are built in earthquake-prone areas (Thompson et al. 2022). One of the best-known examples is the devastating Bam earthquake in Iran, which killed nearly 20% of the local population, mainly due to the collapse of traditional adobe houses (Maheri et al. 2005;Spence 2007). ...
Building with rammed earth has become increasingly popular in recent years because it is highly sustainable and has little environmental impact. More than half of the world's population lives in earthen houses, many of which are located in earthquake-prone areas such as Croatia. However, their seismic performance still needs to be researched, especially considering local construction techniques. One of the first steps in this process is the experimental testing of such walls. Four models of rammed earth walls were constructed using traditional local building techniques and experimentally tested under in-plane cyclic loading to investigate their seismic behaviour. The model walls were built using locally available soil material. The new particle size distribution envelope for determining the suitability of soil material for rammed earth construction was proposed for the first time. The building material was chosen according to the envelope. Moreover, walls were made using two different material compositions—i.e., natural soil from eastern Croatia and “man-made” soil with the addition of fine gravel. The main objective, the seismic performance of the RE walls, was evaluated in terms of their bearing capacity, behaviour after yielding, failure mode, stiffness degradation, initial elastic stiffness, and energy dissipation capacity.
... The use of available local materials where there are few forest resources as well as their structural, thermal, and acoustic properties have stimulated its utilization even at the present day [3], [4]. Even more, the technique has experienced a revival and some guidelines and standards have been proposed [5]. Unfortunately, these types of structures are susceptible to natural deterioration, especially if they are not properly maintained [6]. ...
There is a significant number of structures in the world built with earth materials that deteriorate over time. Typically, this deterioration is neither quantified nor used as input for safety analysis of ancient infrastructure. The aim of this work is to propose a novel way to consider the influence of the weathering on the mechanical properties of adobe units. To achieve this objective, adobe samples recovered from a deteriorated sector (old adobe) of a colonial-style chapel built in adobe (Tausa, Colombia) and similar materials from a local soil deposit as a source for restoration of the chapel (new adobe) were studied. Samples using the new adobe were prepared by compaction under controlled moisture. Half of the samples of new adobe were exposed to ambient conditions while the other half and old adobe samples were subjected to accelerated ambient conditions by using a weathering machine (controlling UV radiation, temperature, and moisture). Samples were tested at different periods by unconfined and triaxial compression tests. Results show that old adobe is not sensitive to weathering while new adobe exhibit variations in strength and stiffness. It was observed that these properties in new adobe initially increase with exposure to weathering until reaching twice than those obtained in old adobe samples but tend to reduce with longer periods of exposure. Therefore, deterioration factors of up to two are proposed for vulnerability and safety analysis of new constructions in these materials. Deterioration factors are proposed to be used as a first approximation to quantify the climatic effect over the mechanical response of the adobe.
... However, most of earth construction nowadays is located in less developed countries, and has been associated with low-income status [2], which could possibly explain the low attention that these constructive solutions have been given in the majority of the developed countries. This poor interest in earth constructions may be the cause of the scarce number of specific guidelines and construction codes [3]. Earth construction comprise a set of techniques depending on the properties of the soil use for the mix, and specially their humidity content. ...
While rammed earth structures are a sustainable design alternative, they are particularly vulnerable to horizontal forces such as seismic loads. Traditional seismic design techniques follow four main principles. (i) Improving connections and forming closed contours. (ii) Stabilizing structural elements by providing resistance and deformation capacity, and by improving the diaphragm action of floors. (iii) Allowing partial collapse through redundancy of structural elements. (iv) Counteracting horizontal loads by providing additional resistance with new structural elements. In this work, special attention has been given to external reinforcements such as TRM (Textile Reinforced Mortars), which have given good results in masonry walls. The references of the use of TRM in earthen walls are scarce, but TRM has been found to increase the compressive and shear strength and ductility of rammed earth. In this paper, special attention is given to the bonding phenomena based on experimental results with TRM reinforced masonry elements. Even in cases with severe damage due to fire exposure, TRM could improve the mechanical response of masonry walls under combined gravity loads and in-plane cyclic shear forces. Carbon fibers showed the best performance after high-temperature exposure, but debonding failure can occur when the TRM-masonry interface is damaged. In the case of TRM applied to rammed earth walls, the bonding between the two materials is expected to be poor; therefore, special connectors would be required to ensure anchorage of the TRM to the earth surface.KeywordsRammed EarthMasonrySeismic behaviorStructural retrofittingFire damageTRMBonding
... Furthermore, susceptibility to climatic parameters, including humidity and solar radiation, introduces internal variations in the material, thereby compromising its structural performance. Additionally, the fragile nature of this construction type poses a considerable risk, particularly during seismic events, potentially leading to structural weakening or even imminent collapse [3][4][5]. ...
Heritage buildings in high seismic hazard areas usually have high vulnerability due to many factors affecting their seismic performance, including material properties, construction procedures applied and preservation conditions. One especially vulnerable structural system used for thousands of years, is the one using compacted soils as a construction material, called rammed earth structure. As rammed earth walls dry and harden, material properties and strength increases. However, weather phenomena during time like storms, floods, ice and snow change walls water content and could change overall structural behavior if there is no protection covers over walls. The aim of this work is to analyze the influence of weather on the seismic performance of rammed earth walls. Water content profiles of two selected walls were calculated and evaporation flux was modelled from experimental data in reduced scale models inside a climatic chamber. After, a finite element model was used for computing dynamic linear and nonlinear performance of earthen walls subjected to selected strong motion records, in different weather conditions. Results indicated that wall shear modulus increase as matric soil suction increase, rising earthen wall’s stiffness in dry conditions, increasing vibration frequencies. Under different water content situations, wall’s stiffness change, vibration frequencies decay and seismic performance changes considerably. Nonlinear walls’ behaviour indicates variable differences between dynamic results under saturation and under residual dry conditions. Those differences will have considerable impact in the design, construction, strengthening or rehabilitation programs on rammed earth buildings, impact that has been neglected when considering earthquake resistance and vulnerability of heritage constructions.KeywordsRammed earth wallsweather impactseismic performancematric soil suctionpesidual dry conditions
... Earthen building materials not yet covered by DIN standards are regulated in the Lehmbau Regeln (clay-building rules) [39]. At the international level, similar standards are under development [40][41][42][43][44][45]. However, although structures made of CMMs are built worldwide [46], there is still a considerable lack of uniform specifications and regulations both for the suitability testing of the materials used and for quality monitoring [47,48]. ...
Increasing demand for sustainable, resilient, and low-carbon construction materials has highlighted the potential of Compacted Mineral Mixtures (CMMs), which are formulated from various soil types (sand, silt, clay) and recycled mineral waste. This paper presents a comprehensive inter- and transdisciplinary research concept that aims to industrialise and scale up the adoption of CMM-based construction materials and methods, thereby accelerating the construction industry’s systemic transition towards carbon neutrality. By drawing upon the latest advances in soil mechanics, rheology, and automation, we propose the development of a robust material properties database to inform the design and application of CMM-based materials, taking into account their complex, time-dependent behaviour. Advanced soil mechanical tests would be utilised to ensure optimal performance under various loading and ageing conditions. This research has also recognised the importance of context-specific strategies for CMM adoption. We have explored the implications and limitations of implementing the proposed framework in developing countries, particularly where resources may be constrained. We aim to shed light on socio-economic and regulatory aspects that could influence the adoption of these sustainable construction methods. The proposed concept explores how the automated production of CMM-based wall elements can become a fast, competitive, emission-free, and recyclable alternative to traditional masonry and concrete construction techniques. We advocate for the integration of open-source digital platform technologies to enhance data accessibility, processing, and knowledge acquisition; to boost confidence in CMM-based technologies; and to catalyse their widespread adoption. We believe that the transformative potential of this research necessitates a blend of basic and applied investigation using a comprehensive, holistic, and transfer-oriented methodology. Thus, this paper serves to highlight the viability and multiple benefits of CMMs in construction, emphasising their pivotal role in advancing sustainable development and resilience in the built environment.
... Other ways of recycling nonbiodegradable waste 15,23,24 , such as plastics, are considered low-cost materials. Furthermore, some researchers have developed user-friendly material that is accessible through a variety of inventions and technics, including compressed earth blocks [25][26][27][28][29] , dome construction [30][31][32] , rammed earth [33][34][35] , and vault construction [36][37][38] . Some even relate the advanced technologies 39 (e.g. ...
Building material is one of the essential aspects in accommodating the supply and demand of low-cost housing in Indonesia. Recently, several researchers have devoted much time and effort to developing waste recycling for building materials since it is more ecologically benign, particularly for non-degradable waste. This article focuses on recycling disposable diaper waste as composite material for a structural and architectural component of the building based on Indonesian building standards. In addition to offering a broad perspective on the implementation of experimental findings, the design scenario comprised the construction of low-cost housing with a floorplan area of 36 m². The experimental results indicate that disposable diapers waste to use as composite materials of the building has a maximum capacity of 10% for structural components and 40% for nonstructural and architectural components. The prototype housing also reveals that 1.73 m³ of disposable diaper waste can be decreased and utilised for a housing area of 36 m².
... The earthen building materials not yet covered by DIN standards are regulated in the Lehmbau Regeln [30]. At the international level, similar standards are under development [31][32][33][34][35][36]. However, although structures made of CMM are built worldwide [37], there is still a considerable lack of uniform specifications and regulations both for the suitability testing of the materials used and for quality monitoring [38,39]. ...
An inter- and transdisciplinary concept has been developed, focusing on the scaling of industrial circular construction using innovative compacted mineral mixtures (CMM) derived from various soil types (sand, silt, clay) and recycled mineral waste. The concept aims to accelerate the systemic transformation of the construction industry towards carbon neutrality by promoting the large-scale adoption and automation of CMM-based construction materials, which incorporate natural mineral components and recycled aggregates or industrial by-products. In close collaboration with international and domestic stakeholders in the construction sector, the concept explores the integration of various CMM-based construction methods for producing wall elements in conventional building construction. Leveraging a digital urban mining platform, the concept aims to standardize the production process and enable mass-scale production. The ultimate goal is to fully harness the potential of automated CMM-based wall elements as a fast, competitive, emission-free, and recyclable alternative to traditional masonry and concrete construction techniques. To achieve this objective, the concept draws upon the latest advances in soil mechanics, rheology, and automation and incorporates open-source digital platform technologies to enhance data accessibility, processing, and knowledge acquisition. This will bolster confidence in CMM-based technologies and facilitate their widespread adoption. The extraordinary transfer potential of this approach necessitates both basic and applied research. As such, the proposed transformative, inter- and transdisciplinary concept will be conducted and synthesized using a comprehensive, holistic, and transfer-oriented methodology.
