Renewable Building Material Research Articles

Innovative robotic-woven willow-clay-composite ceiling elements

Abstract The construction sector contributes 36% to global final energy use and 39% to energy-related CO2 emissions. Consequently, it is imperative to focus on quantifying and reducing environmental impacts e.g., via renewable building materials. The combination of fast-growing willow as tension reinforcement for regionally available and compression bearing clay seems a promising approach. The new attempt is based on the idea of full circularity, as the willow clay composite modules are in the first loop dismountable and can be rearranged and reused for another life cycle. When the composite material comes to its end-of-life, the materials can be theoretically fully recovered. To assess the environmental sustainability of such an innovative composite structure for the first time, a simplified cradle to grave Life Cycle Assessment is performed. The investigation is based on experimental data of the 1 to 1 scale robotically woven willow-clay-composite ceiling demonstrator. First results reveal hot spots, especially in the supply chain of the prototype production process but compared to conventional steel concrete ceiling, the innovative biobased composite is capable to function as a CO2 sink over the entire life cycle. In addition, the resource problem of timber could be circumvented accordingly.

Natural geometrical variations of Italian Phyllostachys edulis bamboo culms for construction purposes

Amid the increasing scarcity of raw materials, utilizing bamboo as a renewable building material offers significant environmental and economic benefits for the European construction sector. However, in Europe, the use of bamboo for construction remains limited due to a lack of studies on geometrical and material characteristics of European-cultivated bamboo species. Although bamboo is not typically grown in Europe, the number of bamboo plantations is steadily increasing in countries like Spain, France and Italy. Bamboos growing in temperate climates, however, are exposed to different environmental conditions during growth compared to bamboos from subtropical and tropical climates, such as those in China or Vietnam. As bamboo’s geometric properties are strongly influenced by the environmental conditions during growth, it is essential to investigate how bamboo culms of the same species grown in Europe compare to those from other regions. The present article reports findings on the geometry and geometric imperfections of 90 four-meter Italian bamboo culms. First, the Italian Phyllostachys edulis bamboo culms examined in this study are briefly introduced. Following, geometric imperfections of bamboo culms are defined, and the geometry measurement concept is presented. Subsequently, variations in internode lengths, diameters, wall thicknesses, ovalities, stem tapers and pre-deflections are described and analyzed. Finally, the findings from the Italian culms are compared with those from Asian Phyllostachys edulis. In summary, this article enhances the understanding of the geometric properties of bamboo grown in Europe, thereby advancing the use of cultivated bamboo culms in Europe and improving the overall understanding of bamboo characteristics across different climatic zones.

Development and property optimization of a sustainable phosphogypsum-based cementitious system with ground-granulated blast furnace slag and carbide slag

β-hemihydrate phosphogypsum (β-HPG) is a promising renewable building material with the potential to reduce phosphogypsum (PG) stockpiles significantly. However, its application is hindered by the low mechanical strength, subpar water resistance, and presence of hazardous components. In this study, ground-granulated blast furnace slag (GGBS) and carbide slag (CS) were together with β-HPG into a high-performance and sustainable phosphogypsum-based cementitious material system (PCMS). Various PCMS specimens were prepared by mixing β-HPG (60 %–100 %), GGBS (0–40 %), and CS (0–40 %). To optimize the PCMS properties, the mechanical, water resistance, and toxicity stabilization investigations of PCMS specimens were performed. Also, the mineralogical and microstructure characteristics of PCMSs were analyzed. The results highlighted that ternary PCMS presented excellent compressive strength and softening coefficient, with low water absorption and P, F leaching concentrations. The formulation with 60 wt% β-HPG and a GGBS/CS ratio of 3:1 showed the best overall property. The primary hydration products included ettringite (AFT), C-(A)-S-H gel, and dihydrate gypsum, contributing to the strength development, water resistance, and toxicity stabilization of PCMS. Furthermore, The increased proportion of GGBS promoted the formation of hydration products, improving the gypsum crystal structure and thus optimizing the properties of PCMS. This study provides valuable insights for further development of green building materials and environmental protection.

Application and performance evaluation of recycled building materials in civil engineering

The concept of renewable materials has received extensive advocacy and promotion in the ongoing development of the construction industry. Furthermore, emerging renewable building materials, such as bio-based composite materials, are continually evolving and gradually being incorporated into civil engineering applications. This paper focuses on the application and performance assessment of recycled building materials in civil engineering. As a crucial component of environmental protection and sustainable development, recycled building materials possess vast potential for application. In this article, the characteristics of common materials such as recycled concrete, recycled steel, and recycled glass are introduced, and their mechanical performance, durability, and other vital attributes are evaluated. Finally, the feasibility and challenges of recycled building materials are analyzed, along with discussions on sustainable development strategies and policy support. The comprehensive research results demonstrate the significant role of recycled building materials in promoting sustainable development in civil engineering, warranting increased support and promotion at the policy and societal levels.

Experimental assessment of modal properties of hybrid CFRP-timber panels

Hybrid timber composites are becoming increasingly widespread to efficiently enhance timber performance. While carbon fibre reinforcement has been explored for strength in timber structures, its impact on vibration performance remains understudied and is crucial as mass timber buildings extend their spans and heights. This work explores the effect of carbon fibre reinforcement on the vibration performance parameters of CLT floor systems. Natural frequency, mode shape, damping and stiffness parameters are evaluated from experimental testing using the Natural Excitation Technique (NExT) combined with the Eigensystem Realization Algorithm (ERA) and robust techniques for selection of physical dynamic properties, verified against numerical finite element models. The findings reveal that, in the case of three-ply Cross-laminated Timber (CLT) panels with depths ranging from 115 mm to 135 mm, introducing reinforcement at ratios below 0.67% led to an enhancement in frequencies, registering an increase of 6% to 11%, although not explicitly accounting for changes in environmental conditions. Moreover, these reinforced panels showed a relevant increase in effective flexural stiffness, ranging from 15% to 22%, when compared to their unreinforced counterparts. This means an improved maximum span of around 4%–6% within current design limits for timber floors influenced by vibration performance. These findings enhance the understanding and design of high-performance composite timber floors, promoting the use of renewable building materials in construction.

To renovate or build with wood? Results from Finnish citizen survey data

Finland shows strong support for reducing its climate footprint originating from the built environment as part of the national carbon neutrality goal by 2035. Two prime examples are increasing wood use in construction and favoring building renovation to alleviate emissions from the use of virgin construction materials. However, the open question remains whether citizens also support these decarbonization pathways. By using national-level data from a randomly sampled citizen survey in Finland (n = 1448), we model citizen preferences to these two decarbonization pathways. The results suggest that a preference to renovate rather than to build anew is shown by respondents of the female gender; over 55 years of age; with a lower household equivalent income; and possessing housing property investment. Wood material is positively favored by respondents with higher age; a lower household equivalent income; living in smaller population centers in the countryside; and owning forestland. Interestingly, the effect of climate agency was negative in both models. This can be interpreted in the wood material case as reflecting conflicting views of negative environmental effects from forest harvesting to produce renewable building materials. In the renovation model case, we argue that the climatic impact of renovations remain weakly understood by citizens in Finland, given that the media and national regulations emphasize operational emissions. These results benefit both policy makers and municipal-level decision making in understanding of acceptability of wood material use and building retrofits among the general public.

Experimental Study on the Effect of Date Palm Powder on the Thermal and Physico-Mechanical Properties of Gypsum Mortars

Date palm leaves have been diachronically applied in building materials in the Middle East and North Africa (MENA) region, so as to enhance specific properties, such as volume stability and strength. This research work concerns an experimental study on the impact of date palm leaflet powder (DPLP) on the thermal and physico-mechanical properties of gypsum mortars. A series of mortar compositions were prepared with different proportions of DPLP (0, 1, 3, and 5% w/w of binder) and variant particle size (0.5, 1, and 1.5 mm). The results showed that the mortars containing DPLP exhibited significant changes in their properties due to variations in DPLP concentration and particle size. Increased DPLP led to lower density, higher porosity, and water absorption rate, whereas mechanical strength and thermal conductivity were decreased according to the DPLP proportion and size. This research provides valuable insights into the use of sustainable and renewable building materials, highlighting the benefits of exploiting agricultural waste in the constructional sector. The findings lay the groundwork for future research and innovation in environmentally friendly construction technologies.

Electrokinetic-mechanism of water and furfural oxidation on pulsed laser-interlaced Cu2O and CoO on nickel foam

The electrocatalytic oxidation of biomass-derived furfural (FF) feedstocks into 2-furoic acid (FA) holds immense industrial potential in optics, cosmetics, polymers, and food. Herein, we fabricated CoO/NiO/nickel foam (NF) and Cu2O/NiO/NF electrodes via in situ pulsed laser irradiation in liquids (PLIL) for the bifunctional electrocatalysis of oxygen evolution reaction (OER) and furfural oxidation reaction (FOR), respectively. Simultaneous oxidation of NF surface to NiO and deposition of CoO and/or Cu2O on NF during PLIL offer distinct advantages for enhancing both the OER and FOR. CoO/NiO/NF electrocatalyst provides a consistently low overpotential of ∼359 mV (OER) at 10 mA/cm2, achieving the maximum FA yield (∼16.37 mM) with 61.5% selectivity, 79.5% carbon balance, and a remarkable Faradaic efficiency of ∼90.1% during 2 h of FOR at 1.43 V (vs. reversible hydrogen electrode). Mechanistic pathway via in situ electrochemical-Raman spectroscopy on CoO/NiO/NF reveals the involvement of phase transition intermediates (NiOOH and CoOOH) as surface-active centers during electrochemical oxidation. The carbonyl carbon in FF is attacked by hydroxyl groups to form unstable hydrates that subsequently undergo further oxidation to yield FA products. This method holds promise for large-scale applications, enabling simultaneous production of renewable building materials and fuel.

Characterization of a Bio-Composite Material (Natural Hydraulic Lime/Date Palm Leaflet) for Architectural Restoration

This scientific investigation aims to characterize the physical and mechanical properties of a new biomaterial designed for architectural restoration. The biomaterial studied is a composite of natural hydraulic lime (NHL) and date palm fibre. The study reports the first experimental characterization of these restorative materials. A series of mortar compositions were prepared with different particle size (0.5, 1, and 1.5 mm). The results showed that the mortars containing DPL exhibited significant changes in their properties due to variations in particle size. Increased DPLP led to lower density but whereas mechanical strength. This research provides valuable insights into the use of sustainable and renewable building materials, highlighting the benefits of exploiting agricultural waste in the constructional sector. The findings lay the groundwork for future research and innovation in environmentally friendly construction technologies.

Achieving sustainable built-environment using bamboo composite frame system with cow-dung masonry infills

In today's rapidly urbanizing world, there is dire need for adopting the principles of green/ sustainable built-environment so as to mitigate the ill effects of environmental degradation and climate change. However, demand for housing is on rise in developing countries like India, where sizeable population, especially the low-income strata, still lacks decent quality structurally safe housing. Extensive use of concrete and steel in construction over more than a century has led to detrimental environmental effects such uncontrolled release of greenhouse gases/ pollutants, deforestation and erosion, leading to now visible outcomes of climate change. Bamboo, on other hand provides a sustainable alternative to concrete and steel as a building material since it absorbs the atmospheric carbon dioxide, produces more oxygen than timber producing trees and is a lightweight and renewable building material. Unlike timber, it matures in four to five years and being grass family, is replenishable in nature. However, from structural point of view, the main drawback of bamboo culm is its large slenderness ratio, which renders it weak in resisting bending and compressive loads. This paper presents an alternate structural system utilizing fibre reinforced bamboo composite (FRBC) to overcome the structural deficiency of a single shoot bamboo and build a prototype structure after detailed laboratory evaluation and structural analysis. Structural elements made from FRBC are utilized for fabricating a prototype 3D frame structure, measuring about 24 m2 in plan, representing a modular unit amenable to horizontal and vertical expansion. Eco-friendly materials like cow-dung based bricks and mortar, which offer net zero additional carbon dioxide emissions and circumvent reliance on cement and river sand, have been utilized as masonry infills after structural evaluation. The built structure provides a proof-of-concept demonstration of the feasibility of using bamboo and cow-dung, sustainable building materials, for achieving a structurally safe built-environment. The technology is especially suitable for countries like India which are endowed with tropical climatic conditions. By adopting such environmentally friendly alternatives, the construction industry can create a healthier environment while addressing housing and infrastructure needs in sustainable manner.

Hygrothermal Performance of Bio-Based Exterior Wall Constructions and Their Resilience under Air Leakage and Moisture Load

The use of renewable building materials in construction is crucial to minimising the environmental impact of new buildings. Bio-based building materials have a wide range of positive properties, many of which are due to their hygroscopic behaviour. The purpose of this study is to investigate the hygrothermal performance of chopped straw, sheep’s wool, and cellulose insulated timber frame external wall assemblies in the presence of air leakage and high indoor relative humidity. For this purpose, tests with different moisture contents, overpressures, and defects in the airtight layer were carried out in an outdoor test stand over a period of 18 months. The results were compared with a conventional mineral wool insulated construction. Both sheep’s wool and cellulose are particularly fault-tolerant insulation materials in combination with timber frame constructions. All three bio-based insulations, despite defects in the airtight layer, showed no mould-prone moisture content. An installation level insulated with sheep’s wool can increase the fault tolerance of constructions with insulation made of hygric and more sensitive building materials. For chopped straw and cellulose, the measured U-value was lower than expected. Further in situ measurements of bio-based structures are important to gain confidence in their hygrothermal behaviour and to increase their use in multi-storey construction.

Simulation calculation and analysis of building energy consumption of multi-story glued laminated timber structures

As the only renewable building material, wood has a strong carbon sequestration effect. Thus, timber structures have the natural advantages of saving energy and reducing emissions. Currently, the research objects of building energy consumption are rarely timber structures. To further control the operational energy consumption of timber structures, this paper takes six-story glued laminated timber beam-column frame and light wood-frame shear wall structures as the research objects. Building energy consumption research is conducted through testing the heat transfer coefficient of the envelope structure, air circulation ratio, and Building Information Modeling (BIM) technology on-site. The results show that the energy consumption of the building is consistent with the current energy consumption of small- and medium-sized office buildings, and the heat gain and loss of the building are mainly due to solar radiation and heat conduction of the envelope, respectively. The airtightness of the building has the greatest influence on the energy consumption of the building, and the type of building structure and window-to-wall ratio have little influence on the energy consumption of the building.

The use and re-use of timber structure elements, within a waste hierarchy concept, as a tool towards circular economy for buildings

Wood is the only natural renewable building material, produced by photosynthesis. It has the ability to preserve the stored carbon in its molecular structure as long as it remains within a structure. Timber dwellings are re-gaining recognition worldwide, especially in remote areas due to their aesthetic superiority, durability and harmony with the natural landscape. Research findings, as well as industrial operations indicate that timber buildings present beneficial environmental impacts, compared to other common building materials. Specifically, timber has substantial strength characteristics, low embodied energy, less CO2 emissions and also an easy and fast construction, combined with minimum disruption to the environment. Moreover, timber buildings have a high potential to reduce waste at site and ability for re-use, when designed for future ease of deconstruction, providing the repeated utilization of the used material, known as, the cascading concept. It is already recognized that successful waste management is a measure towards the containment of climate change. Using timber structures enhances the chances to accomplish the contemporary waste hierarchy concept, which can be implemented according to the application of Design for Deconstruction and Reuse (DfDR) concept, at an early stage. These waste management techniques are strongly related to circular economy, but can only be achieved through the aim of a long-lasting design. Finally, in most countries, the existing building codes should be revised in order to overcome the imposed limitations on the re-use of building materials.

An experimental study for sustaining the architectural heritage value of traditional houses of Bursa

Bursa, the first capital of the Ottoman Empire, is one of the rare historical cities that has survived to the present day without losing its importance. As well as monumental structures such as mosques and Sultan complexes, traditional Bursa houses are also components of architectural heritage that reflect the identity of the city. The traditional building materials of these houses are wood, stone, brick and earth. Today, these materials are known as ecological building materials and their use is very important to ensure sustainability. Especially the application of traditional building techniques based on the use of these materials in restoration works is of great importance in terms of ensuring sustainability not only from an ecological point of view, but also from economic and cultural points of view. In this context, earthen building material consisting of natural raw materials and created by human hands are seen as ecological and renewable building materials. In different parts of the world, many civilizations have used earthen building materials with different usage techniques in the past. This material has not lost its importance to this day. In this study, the earthen building materials used in traditional Bursa houses are examined and their role in sustainable architecture is pointed out. For this purpose, a case study was conducted on traditional Bursa houses in three different historic neighborhoods; Hisar, Tuzpazari and Reyhan regions. Representative earthen building materials were taken from 22 traditional houses and listed with their qualities for experimental studies. Characterization tests were carried out on the samples taken from these houses. The results of the experiments have been used to develop some recommendations for the successful implementation of restorations that will help to carry out sustainable heritage conservation work in Bursa.

Building Integrated Photovoltaic (BIPV) Development Knowledge Map: A Review of Visual Analysis Using CiteSpace

Achieving zero energy consumption in buildings is one of the most effective ways of achieving ‘carbon neutrality’ and contributing to a green and sustainable global development. Currently, BIPV systems are one of the main approaches to achieving zero energy in buildings in many countries. This paper presents the evolution of BIPV systems and predicts their future trends by deriving a base sample of core papers on BIPV systems from 2012 to 2022 from the Web of Science core database and conducting a bibliometric study using CiteSpace scientific visualisation software. To gain a deeper understanding and grasp of the research progress of BIPV systems, research group discovery, research hotspot analysis, and research frontier detection of the relevant literature were conducted. (1) Research groups on the topic were summarised through author coupling network, publication distribution, and country mapping analysis; (2) Research hotspots on the topic were explored through keyword co-occurrence, keyword emergence, and time zone map analysis; (3) Research hotspots on the topic were explored through literature co-citation timeline maps, literature co-citation categories, and literature co-citation clustering analysis to detect the frontiers of research in the field. Finally, we conclude that research trends in BIPV systems are mainly in the areas of heat transfer, thermal performance, renewable energy, solar cell and renewable building materials, and evaluation systems. In the future, BIPV research and applications will move towards interdisciplinary and multinational cooperation, which will maximise the benefits of clean energy conversion in buildings. It will also provide researchers and practitioners with a clearer understanding of BIPV research trends and hotspots, and provide new directions for future research.

AIR PASSENGER TERMINAL DESIGN IN THE FRAMEWORK OF THE SUSTAINABLE DEVELOPMENT STRATEGY

The construction of new passenger air terminals, reconstruction or expansion of existing ones should take place with a decreasing in the impact on the environment, taking into account the strategy of sustainable development and environmental, social and economic aspects recommended by the Global LEED certification system. The construction sector is beginning to realize that sustainability is key and technology has an important role to play in helping to achieve the Sustainable Development Goals. Building information modeling (BIM) can help achieve all of the Sustainable Development Goals. BIM can impress with its performance. Primarily, BIM realizes this advantage through its ability to facilitate communication and coordination, identify clashes, and reduce costs. The information model of the air passenger terminal contains not only geometric data, but also all energy data and information such as insulation type, opaque enclosure structures, glazed structures, energy sources, climate data, aspects of heating, cooling and ventilation. In this case, engineers can work with building energy model BEM. The design, construction and operation of air passenger terminals must be carried out in accordance with the design dimensions of sustainable terminals, it is necessary to implement modern technological developments, such as intelligent systems, BIM-technologies, ecological and renewable building materials, alternative energy sources.

Climate-resilient and resource-conserving architecture through renewable building materials and microclimate improvement

Due to climate change, together with the need to reduce the ecological footprint and the future resource shortages, a climate-resilient and resource-conserving architecture must be reinforced. Dealing with the issue of resources not only affects the materialisation of the building, but also the handling of resources on the building site. The interactions between the environment (sun, wind, precipitation), buildings, sealing, plants and people form a complex system in which small changes in few factors can influence the situation on a large scale. In this context, topics such as microclimate improvement around built infrastructure through greening and rainwater management, will gain in importance. The correct assessment of measures for a sustainable and resilient building is extremely complex and time-consuming and requires extensive, multi-layered know-how and experience. This paper analyses the project “House of Learning“ (MAGK Architekten) and its immediate surroundings and focuses on its climate resilience and neutrality, proposing improvement measures based on the interaction of blue and green infrastructure and the building. The potential favourable conditions are evaluated through microclimate simulations and planning principles implying an integral approach which includes landscape gardeners, building planners and constructors, as well as decision-makers.

Incentive Regulation of Construction Waste Resource Recycling: Subsidy and Tax Incentive

Construction waste destroys the sustainability of environment and economy. In the study of game theory at present, the construction waste resource-based products supply chain only considers that there is only one type of enterprise producing renewable building materials or new building materials in the market, but in the construction market, there is no single type of enterprise. It isvery important for government to protect the environment and promote the resource utilization and development of construction waste. Therefore, this study establishes a game theory model between traditional building materials enterprise and construction waste recycling enterprise, which considers the decision-making behavior of enterprise under no regulation, subsidy incentive regulation, or tax incentive regulation. The findings are listed as follows: (1) both subsidies and tax incentives can effectively improve the economic benefits and production initiative of construction waste recycling enterprise. (2) The impact coefficient of unit new building materials on the environment and the tax rate of unit new building materials are the key factors that affect government decision-making. (3) Resource utilization cost coefficient and builder’s preference for renewable building materials have a great impact on the profits of construction waste recycling enterprise. These results will provide reference for the government to formulate incentive regulations and promote the development of construction waste resources.

Evaluation of dry mass timber assemblies and comparison to cementitious toppings

Mass timber construction is an increasingly common way of building taller and larger wood buildings utilizing renewable building materials with lower embodied carbon. Given the desire for the aesthetic design of exposed mass timber ceilings, it is common for these mass timber panels to require an additional subfloor decoupled by an acoustic interlayer to achieve IBC 1207 requirements. In the efforts to minimize added structural weight and overall embodied carbon, various dry linings were tested as an alternative to traditional cementitious toppings. A 175mm cross laminated timber (CLT) panel was constructed in the laboratory, and numerous ASTM E90 and ASTM E492 tests were performed. This analysis examines the role of dynamic stiffness of the acoustic interlayer and various mass layers in the resulting performance. Assembly transmission loss data from ASTM E90 testing are assessed to understand if it agrees with mass law.

Construction enterprises’ adoption of green development behaviors: an agent-based modeling approach

Many previous studies have used performance evaluation to explore the impact of environmental regulation on the green development of enterprises. However, there are few studies on the process by which enterprises adopt green development behavior. Here, we aim to simulate the whole process by which Chinese construction enterprises adopt green development. We also consider impact of environmental regulation and industry clusters in this process. Using agent-based modeling, we construct a computational experimental simulation model for the adoption of green development behavior by construction enterprises. The model considers the organizational behavior characteristics of construction enterprises and the evolutionary characteristics of the renewable construction materials market. Our results show that in terms of renewable building materials, construction enterprises that actively adopt green development behavior are more sustainable than those that do not. Moreover, with the implementation of sustainable environmental regulations, more enterprises are passively adopting green development behaviors. However, unsustainable environmental regulations do not have a positive effect. The formation of industrial clusters is also conducive to promoting companies’ adoption of green development behaviors. Therefore, construction enterprises should take the initiative to adopt green development behavior and migrate to industrial agglomerations. This practice is not only beneficial to the sustainable operation of the enterprise and the expansion of the enterprise scale, it will also have an optimization effect on the external environment. Here, we take construction enterprises as the breakthrough point and expand research on enterprise green development. We also provide a theoretical basis and insights for enterprises with environmental responsibility to engage in green development behavior.