• Energy Research
• 2021-2025close
• civil engineering close
• 12. Responsible consumption close

One effective method to minimize the increasing cost in the construction industry is by using coal bottom ash waste as a substitute material. The high volume of coal bottom ash waste generated each year and the improper disposal methods have raised a grave pollution concern because of the harmful impact of the waste on the environment and human health. Recycling coal bottom ash is an effective way to reduce the problems associated with its disposal. This paper reviews the current physical and chemical and utilization of coal bottom ash as a substitute material in the construction industry. The main objective of this review is to highlight the potential of recycling bottom ash in the field of civil construction. This review encourages and promotes effective recycling of coal bottom ash and identifies the vast range of coal bottom ash applications in the construction industry.

Ordinary Portland cement (OPC) is the primary binder of concrete, accounting for approximately 5% to 7% of greenhouse gas (GHG) and carbon dioxide (CO2) emissions with an annual production rate of more than 4 billion tons. It is critical to reduce the carbon footprint of concrete without sacrificing its performance. To this end, this study focuses on the use of water hyacinth ash (WHA) as a pozzolanic binder in the production of concrete as a partial replacement for cement. Four mixes are designed to achieve C-25-grade concrete with varying proportions of cement replacement with WHA of 0%, 5%, 10%, and 15% of the cement weight. Extensive experiments are performed to examine the workability, strength, durability, and microstructure of concrete specimens. The test results confirm that incorporating WHA in concrete improved its workability, strength, and durability. The optimal results are obtained at the maximum OPC replacement level, with 10% WHA. The use of WHA as a partial replacement for cement greatly reduces the energy required for cement production and preserves natural resources. More research is needed to use WHA on a large scale to achieve greater sustainability in the concrete industry.

Abstract Sustainable retrofitting of existing buildings is a prerequisite for achieving climatic and energy objectives in the EU. Thus, practical tools supporting the evaluation and decision-making process when planning retrofit interventions are required. In specific areas, in addition to energy efficiency, the improvement in building resilience to natural hazards is requested; in several European regions, seismicity poses a significant hazard. This study aims to analyse the state-of-the-art of the integrated methods for the implementation of structural and energy retrofitting. The work consists of reviewing available tools, international sustainability protocols, and methods specifically developed for combined energy and seismic assessment. In the first group of methods, assessment is independently referred to specific criteria for energy performance and seismic safety, quantified according to available codes. Besides, in a second group, integrated evaluation is achieved considering ‘equivalent’ initial or life-cycle costs associated with energy consumption and seismic vulnerability. The collected methods were evaluated for qualitative requirements for optimal integration, such as multidisciplinary, life-cycle approaches, and other indicators. Finally, a critical evaluation is provided, highlighting what can be used for future developments toward a sustainable and resilient retrofitting of existing European buildings.

Nowadays, the increasing demand for concrete is causing serious environmental impact including pollution and waste generation, rapid depletion of natural resources, and increased CO2 emission. Incorporating natural fibers in concrete can contribute toward environmental sustainability. This paper is concerned with the use of natural fibers obtained from the plant species Phragmites australis (PA). The plant is invasive, and rapidly grows abundantly along rivers and waterways, causing major ecological problems. This research is part of a wide range investigation on the use of natural fibers produced from the stem of PA plants in concrete. Using a machine, plant stems were crushed into fibers measuring 40 mm in length and 2 mm in width, and treated with 4% NaOH solution for 24 h. A total of four concrete mixes were prepared with varying additions of treated fibers, ranging from 0% to 1.5% (by volume) with water to cement ratio of 0.5% (by volume). Concrete specimens were tested at 3, 7, and 28 days. Testing included compressive strength, density, total water absorption, and capillary water absorption. The results show that incorporating PA natural fibers reduces the water absorption by total immersion and capillary action by up to 45%. Moreover, there is a negligible decrease in concrete density and strength when fibers were added. It is concluded that adding up to 1.5% natural PA fibers to concrete is a feasible strategy to produce an eco-friendly material which can be used in the production of sustainable building material with adequate mechanical and durability performance.

This study focuses on addressing the challenge of society’s consumer demands through sustainable production processes, as outlined by Sustainable Development Goal 12 established by the United Nations. In this context, this study aims to assess the durability of eco-friendly mortars with mineral waste as alternative raw materials, considering the alkali-aggregate reaction (AAR). For this purpose, scheelite tailing (ST) was used to partially replace Portland cement (PC), and quartzite sand (QS) was used to fully replace conventional sand. The ST was ground and sieved (<75 μm), and part of it was used in its natural form, while the other part was calcined (1000 °C for 1 h). A mixture experimental design was created to select the compositions with the best mechanical performance. All the mortar mixtures were produced with a cementitious material to QS ratio of 1:3. Three mortar compositions (0% ST, 30% natural ST, and 30% calcined ST) were selected to study the resistance to the AAR. Linear expansion measurements, compressive strength tests, X-ray diffraction, thermogravimetric analysis, and scanning electron microscopy were conducted to evaluate the phases formed and the mechanical behavior of the mortars in relation to the AAR. The expansion results demonstrated that QS does not exhibit deleterious potential. Regarding the use of ST, the results indicated that it is possible to partially replace PC with calcined ST without significantly compromising the mechanical performance and durability of the mortars. However, the use of non-calcined ST is not recommended, as it presents deleterious effects on the mechanical properties of the mortars. This study highlights a new sustainable mortar alternative for use in construction without future degradation of its properties.

Accelerated pavement testing (APT) facilities has been demonstrated for years as a multi-purpose solution for pavement and non-pavement research. Even though APTs are widely known in the pavement industry, little has been publicized about their successful applications in non-pavement research. This paper provides a survey of APT applications in non-pavement research. The purpose of the survey is to review and encourage APT owners and agencies to explore the opportunities that APT facilities can present to promote non-pavement research initiatives. The survey demonstrates the ability of APTs to conduct research for bridges, transportation technology, drainage, geotechnical engineering, automobiles, environmental engineering, highway safety, among others. Non-pavement research can be incorporated into APT programs to diversify funding sources for research operations and promote cooperation with other agencies. Finally, suggestions for future and current APTs are made in this paper, including evaluating connected vehicles, work zone applications, smart infrastructure, truck platooning effects on bridge performance, sustainable drainage systems, bridges, advancement in geotechnical methods, sustainable fuels, and unmanned aerial systems.

Numerous studies have been conducted recently on fibre reinforced concrete (FRC), a material that is frequently utilized in the building sector. The utilization of FRC has grown in relevance recently due to its enhanced mechanical qualities over normal concrete. Due to increased environmental degradation in recent years, natural fibres were developed and research is underway with the goal of implementing them in the construction industry. In this work, several natural and artificial fibres, including glass, carbon, steel, jute, coir, and sisal fibres are used to experimentally investigate the mechanical and durability properties of fibre-reinforced concrete. The fibres were added to the M40 concrete mix with a volumetric ratio of 0%, 0.5%, 1.0%, 1.5%, 2.0% and 2.5%. The compressive strength of the conventional concrete and fibre reinforced concrete with the addition of 1.5% steel, 1.5% carbon, 1.0% glass, 2.0% coir, 1.5% jute and 1.5% sisal fibres were 4.2 N/mm2, 45.7 N/mm2, 41.5 N/mm2, 45.7 N/mm2, 46.6 N/mm2, 45.7 N/mm2 and 45.9 N/mm2, respectively. Comparing steel fibre reinforced concrete to regular concrete results in a 13.69% improvement in compressive strength. Similarly, the compressive strengths were increased by 3.24%, 13.69%, 15.92%, 13.68% and 14.18% for carbon, glass, coir, jute, and sisal fibre reinforced concrete respectively when equated with plain concrete. With the optimum fraction of fibre reinforced concrete, mechanical and durability qualities were experimentally investigated. A variety of durability conditions, including the Rapid Chloride Permeability Test, water absorption, porosity, sorptivity, acid attack, alkali attack, and sulphate attack, were used to study the behaviour of fiber reinforced concrete. When compared to conventional concrete, natural fibre reinforced concrete was found to have higher water absorption and sorptivity. The rate of acid and chloride attacks on concrete reinforced with natural fibres was significantly high. The artificial fibre reinforced concrete was found to be more efficient than the natural fibre reinforced concrete. The load bearing capacity, anchorage and the ductility of the concrete improved with the addition of fibres. According to the experimental findings, artificial fibre reinforced concrete can be employed to increase the structure’s strength and longevity as well as to postpone the propagation of cracks. A microstructural analysis of concrete was conducted to ascertain its morphological characteristics.

The difficulty of decomposing solid waste over time has made it a significant global problem because of its environmental impact and the need for large areas for disposal. Among these residues is the waste of the rendering mortar that is produced (falls to the ground) while applied to wall surfaces. The quantity of these materials may reach 200 to 500 g/m2. As a result of local urban development (in Iraq), thousands of tons of these wastes are produced annually. On the other hand, the emission of greenhouse gases in the cement industry has had a great environmental impact. One of the solutions to this problem is to reduce the cement content in the mix by replacing it with less emissive materials. Residues from other industries are considered a relatively ideal option due to their disposal on the one hand and the reduction of harmful emissions of the cement industry on the other hand. Therefore, this research aims to reuse rendering mortar waste powder (RMWP) as a possible alternative to cement in mortar. RMWP replaced the cement in proportions (0, 10, 15, 20, 25, and 30% by weight). The flow rate, flexural and compressive strengths, ultrasonic pulse velocity, bulk density, dynamic modulus of elasticity, electrical resistivity, and water absorption tests of the produced mortar were executed. Microstructural analysis of the produced mortar was also investigated. Results indicated that, for sustainable development, an eco-friendly mortar can be made by replacing cement with RMWP at a rate of 15%, resulting in a 17% decrease in compressive strength while maintaining or improving durability properties. Moreover, the microstructure became denser and more homogeneous in the presence of RMWP.