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Annually, industries related to agricultural products generate substantial volumes of waste biomass, presenting critical challenges for solid waste management due to its environmental and health implications. Pyrolysis emerges as a significant technique for converting such waste into biochar (BC), a material with notable internal microstructure, porosity, and chemical properties, contingent on the feedstock and processing conditions. BC is recognized for its exceptional water retention and alkalinity, primarily utilized for soil enhancement and fertilization. Its application across various fields, particularly in enhancement for sustainability, has gained momentum. This review meticulously explores BC's role in sustainable composites, focusing on geopolymers and alkali-activated binders through a comprehensive examination of existing literature, underscored by bibliometric analysis. This pioneering review, leveraging the PRISMA framework and VOSviewer for bibliometric insights, aims to bridge the research gap in this evolving domain, offering a critical assessment of BC's integration in sustainable construction materials, its challenges, and future research directions. Hence, this pioneering systematic review represents the first-ever exploration within the research domain of BC's applications in geopolymers and alkali-activated materials, marking a foundational step toward understanding its potential and challenges in sustainable engineering practices. [Display omitted] [ABSTRACT FROM AUTHOR]

The use of structural steelwork (SS) for buildings continues to grow worldwide owing to its sustainability benefits. However, the market share of SS in the building sector of Hong Kong greatly lags behind other markets. This paper focuses on providing a comprehensive understanding of the issues that greatly drive or inhibit SS adoption in Hong Kong from a project lifecycle perspective. The methodology encompasses both qualitative and quantitative approaches. Semi-structured interviews were conducted with 28 professionals from developer, structural engineering consultant, main contractor, steel specialist contractor, and steel stockholder companies. The results identified 12 driving factors and 25 barriers affecting SS adoption in Hong Kong. A questionnaire survey with 118 practitioners was carried out to identify the most important driving factors and barriers. The results revealed that "increased speed of construction" and "must-have requirements" were the two most important driving factors; while "shortage of skilled labor", "shortage of supervisors working directly under main contractors", "high construction costs", "shortage of experienced designers and draughtsmen", and "lack of education, training, and design experience on structural steelwork" were the five most critical barriers. This may imply that education and training are needed to improve knowledge and skills of professionals and workers, and thus to ensure an adequate supply of manpower. The findings of this study not only contribute to the existing body of knowledge on SS practices but also provide valuable references for helping practitioners and policymakers to promote sustainable construction methods within the building sector. • Increased speed of construction and must-have requirements are important drivers. • Manpower shortages in the design and construction phases are critical barriers. • High construction cost also inhibits the use of structural steelwork. [ABSTRACT FROM AUTHOR]

In this paper a toolbox (Greenometer) to assess the greenness level of manufacturing companies is proposed. The assessment approach is based on capturing the relative greenness position of any company among other industries from different sectors as well as within the same sector. The assessment was based on selected greenness attributes and their composing indicators at each of the two levels of the developed Greenometer. Geometric Mean Method (GMM) was adopted to be the generic assessment technique for cross industries greenness evaluation, while Data Envelopment Analysis (DEA) was employed to assess the greenness level of intra-industries layer. Three different industrial applications were used to demonstrate the applicability of the developed Greenometer. Results highlighted how the proposed tool can be a useful for manufacturing managers not only in understanding their green performance position at various levels, but also aiding them in their green transformation/improvement efforts. Specifically, the Greenometer assessment scores will help in setting plans through highlighting prioritized areas of required improvement as well as offering quantitative targets and tracking metrics along the transformation journey. [ABSTRACT FROM AUTHOR]

This study incorporates the use phase in the life cycle assessment (LCA) of reinforced concrete structures that are composed of one-way slabs. Sustainable construction is one of the main future objectives of the European Union; therefore, useful and reliable tools will be necessary for its implementation. The usefulness of the LCA for the selection of structural alternatives depends on the data quality. The Environmental Product Declarations collect the production phase of building materials, but it is necessary to incorporate the particularities in the implementation and use phases. This work proposes a stage that considers the use phase in the structural part that does not belong to the building envelope and provides a methodology that reflects the characteristics of each climate zone where it is applied. All of the representative variables to define the structure of a building are combined: column grids, variations in the geometry of one-way slabs, and different materials. A discrete model that incorporates 360 cases is constructed to compare the reliability of the model with a study on real structure projects. The results show the importance of the use phase in residential buildings with respect to the effects generated during the other phases (production, execution and demolition), as well as its high variations, up to 140.4%. [ABSTRACT FROM AUTHOR]

Abstract: Rammed earth is an ancient construction technique that has been gaining renewed attention due to its potential to produce more environmentally sustainable constructions. Yet, studies that quantify the gains in strength by varying key parameters (binder content, dry unit weight) are still limited, hindering an efficient use of resources (materials and energy) when adopting this technique. Seeking to fulfil this gap, this paper presents equations that quantify the effect of parameters (dry unit weight, lime content, and fly ash content) on the compressive strength of Botucatu residual soil – fly ash – lime blends. Such equations allow different values to be assigned to each of these parameters (resulting in distinct strength results). This enables dosages that minimize resource consumption and maximize resource reuse/recycling to be devised. To illustrate that, eight dosages options are proposed for a target strength using the proposed equations and assessed against a number of criteria. The results indicate that dosages that are able to simultaneously minimize resources consumption and maximize resource recycling can be produced. [Copyright &y& Elsevier]

The incessant production of cement has increased the amount of CO 2 being released into the atmosphere; thus, aggravating the issue of global warming which has an adverse effect on the environment. Therefore, a more sustainable approach and a careful review of the existing admixtures used to replace conventional concrete have become highly imperative. To this end, many investigations on geopolymer concrete (GeoPC), which exhibit similar or better durability and high strength when compared to conventional concrete, have been carried out by various researchers. GeoPC concrete has the advantage of cement replacement with supplementary cementitious materials that are combined with alkali activated solutions. GeoPC is a relatively new, innovative and sustainable engineering material with many advantages over ordinary concrete. For example, it exhibits higher early strength, lower natural resource consumption, low cost and ability to form various structural shapes. GeoPC is an essential material that can be used for concrete building repairs, maintenance of road transport infrastructure and reducing the negative environmental effects. Therefore, this paper presents a comprehensive review of GeoPC material, its constituents, production techniques, curing regimes, properties and its potential applications in the construction industry. • Geopolymer concrete has a distinguished property of being reduced the use of vibration and cement. • The main function of developing geopolymer concrete is to reduce the emissions of CO 2 in the atmosphere. • The rate of strength development of geopolymer concrete is mainly relied on the source of material and alkaline activators. • Geopolymer concrete has emerged as a new engineering material, contributing towards sustainable construction products. [ABSTRACT FROM AUTHOR]

Extensive research has devoted to facilitating sustainable construction and demolition waste management. Waste disposal charging scheme is an effective tool in fostering waste reduction and minimising environmental burden. However, the determination of waste disposal charging fee was mostly designed for cost recovery at present rather than meeting the future needs. This study develops a generic system structure for determining an optimum waste disposal charging fee for sustainable development and elaborates dynamic relationships between social/economic factors and waste disposal charging fee. A comprehensive system dynamics model was constructed to predict the optimum waste disposal charging fee by integrating quantitative and qualitative factors from the literature and questionnaire survey, which was then validated with the historical data in Hong Kong. The use of this model assesses and projects the structure, interactions of the complex system in waste disposal charges in an integrated and holistic manner. Two sets of policy scenario analysis were conducted for evaluating the effects of the newly modified waste disposal charging fee implemented by the Hong Kong government and identifying an optimum range of waste disposal charging fee. The simulation results indicated that the newly modified waste disposal charging fee is ineffective to achieve construction and demolition waste reduction in the long term. To devise policy strategy for sustainable waste reduction, the optimum increment percentage on original landfill and public fill charging fees should not exceed 250% and 400%, respectively. The proposed model serves as a scientific approach for decision-makers to better design the architecture in the complex system of construction and demolition waste management. Image 1 • Behavioural dynamic relationships of charge and waste management are identifed. • System dynamics model can be adopted to determine optimum waste charges. • Newly revised waste charge is insufficient to achieve sustainable waste reduction. • Optimum increases in landfill disposal and public fill fees are within 250% and 400%. • Understanding of generic system structure facilitates waste charge determination. [ABSTRACT FROM AUTHOR]