Microstructural Characterization of Prefabricated Hempcrete Blocks

Sustainable building materials have been developed to reduce the polluting emissions and the exploitation of natural resources of the building sector. Among these materials, an outstanding category is that of nature-based solutions which are produced recovering waste or by-products of agricultural cultivations and using them as vegetal aggregates to replace the traditional ones. This paper focusses on hempcrete which is produced mixing the by-product of industrial hemp cultivation (i.e., shives) and lime to obtain a sustainable, breathable and insulating material. The strength of hempcrete develops through carbonation of the binder that, leading to the formation of calcium or magnesium carbonates and mineralization of shives, determines the microstructure and hence most of the characteristic properties of the material. The aim of this research is to investigate how carbonation influences the microstructure of hempcrete when different recipes are used for blocks production. This study consists in the characterization of the material through techniques such as XRD (X-ray Diffractometry), SEM (Scanning Electron Microscopy) and TG-DTG (thermogravimetric analyses). Moreover, the evolution of carbonation is studied analyzing samples at different maturation times. The investigation of the carbonation reaction degree is also crucial to evaluate the environmental performances of the material because it allows the quantification of the carbon dioxide uptake. Also, periodic characterization allows to assess the durability of hempcrete and to select the best formulation according to the designed application and the corresponding service conditions.

Determinants of sustainable building materials (SBM) selection on construction projects

The complexity and fragmented nature and the multiple stakeholders in the construction industry often make it difficult to come up with a firm decision regarding sustainable building materials selection. The wrong choice could negatively impact the project objective and performance outcome. This study assessed the critical factor influencing the choice of sustainable building materials (SBM) selection on construction projects in the Southeast geopolitical zone of Nigeria. Data were collected using a well-structured questionnaire, non-probability (purposive and snowball) sampling techniques, and an internet-mediated survey. Data analyses were carried out using the appropriate descriptive and inferential statistical tools and exploratory factor analysis (EFA). The study revealed recycled plastic, natural clay and mud, stone, bricks and tile, cellulose, stray bales, grasses, limestone, and wood timber, are the commonly used sustainable building materials. Also, their level of awareness is high while their adoption is moderate. EFA revealed that the major clusters of determinants of the choice of green building materials are: emissions minimisation, low running cost and reusability, low thermal and energy consumption efficiency, low cost and high health and safety consideration and waste minimisation. The key factors influencing the choice of sustainable building materials selection in construction are: reducing greenhouse gas emissions from buildings, materially embodied energy cost, operating and maintenance costs, non-toxic or low toxic emissions generated by the products/materials, recyclability of the building materials, availability of the technical skills, renewable (reusable) properties, inhibiting the impact of buildings on the environment, safety and health of the occupants, and appearance and aesthetic. It is recommended that consideration be given to these factors in selecting sustainable/green building materials in the designs and specifications of construction projects.

SUSTAINABLE MATERIALS AND INNOVATIONS IN CONSTRUCTION

Строительство - отрасль материального производства, в которой создаются основные фонды производственного и непроизводственного назначения: готовые к эксплуатации здания, строительные конструкции, сооружения и их комплексы. В данной статье исследуются инновационные технологии и устойчивые строительные материалы, производство которых подразумевает минимальный ущерб экологии и здоровью населения. Construction is a branch of material production in which fixed assets of industrial and non-industrial purposes are created: ready-to-use buildings, building structures, structures and their complexes. This article examines innovative technologies and sustainable building materials, the production of which implies minimal damage to the environment and public health.

Barriers to the use of sustainable materials in Australian building projects

PurposeAlthough the adverse effects of construction activities on the environment and the need for sustainable construction practices are recognised in both research and practice, any significant shift in the selection and use of construction materials from the sustainability perspective has not taken place in many building projects. Still, conventional construction materials are widely used in building projects in both developed and developing countries. This study attempts to identify the main barriers to the use of sustainable materials in building projects in an advanced economy such as Australia.Design/methodology/approachThis study adopted a questionnaire survey approach to examine the main reasons behind the low usage of sustainable materials in building projects. Based on the relative importance index, exploratory factor analysis and multinomial logistic regression analysis, the study examined the main barrier measures and barrier factors to the use of sustainable materials in building projects.FindingsThe findings reveal that critical barriers to the use of sustainable materials are related to cost and profit considerations, the unwillingness of the key stakeholders to incorporate these materials into building projects, lack of incentives and government policies. The factor analysis reduced the critical barrier measures into three factors: techno-economic considerations, cost and delay concerns and resistance to use. Furthermore, multinomial regression analysis based on the extracted factors identified techno-economic considerations as the main barrier factor to the use of sustainable materials in building projects.Practical implicationsThe empirical results of this research can inform construction practitioners, organisations and policymakers on how to increase the use of sustainable building materials in the construction industry.Originality/valueIdentification of barriers to the use of sustainable building materials is a prerequisite to improve their uptake and use in the construction industry. The study fills a gap in the existing research on the use of sustainable materials in building projects in Australia.

Sustainable Material Awareness, Belief and Readiness in Housing Development

The construction industry is one of the industries accounting for a large proportion of Vietnam's overall GDP. It is also one of the least sustainable industries with extensive use of non-renewable resources. A study on the current situation of occupational awareness of sustainable building materials, identifying factors that prevent the diffusion of sustainable building materials is critical. The present study raised the theoretical basis of using sustainable building materials for the construction industry. Questionnaire data from 130 valid responses were used to carry out statistical analysis and make interpretation of results. The results indicate no significant difference between the two groups of respondents in awareness, belief, and readiness towards sustainable materials. The awareness and readiness levels are higher among construction practitioners who have experience. The present findings might suggest several courses of action to solve the problem of sustainable materials being overlooked. Our research suggests that it is essential for policymakers to encourage stakeholders to consider sustainability more seriously. The research findings have profound managerial implications that experienced practitioners might significantly impact the decision-making process in the realm of sustainable orientation. Future work should concentrate on integrating sustainable building materials into innovative and transformative practices in the construction industry. Keywords: sustainable materials; awareness; belief; readiness; Vietnam; construction industry