With the increasing concerns on the impact of cement production on the environment and the need to protect the environment, the use of mineral additives as cementitious material to partially substitute cement is being considered as an effective option. One of such material is fired clay brick which can be sourced as generated waste from clay brick industry. This has an added advantage of reducing industrial waste and preserving the natural resources. The experimental objective of this study is to examine the possibility of utilizing clay brick waste as partial replacement for Portland cement in concrete. The clay brick was finely ground into powder size, and after grinding, the morphological characterization of the powder materials was carried out using scanning electron microscopy (SEM). Moreover, the chemical composition of the brick material was determined using X-ray fluorescence (XRF). Laboratory tests were carried out to determine the workability, split tensile and compressive strength properties of the concrete with 0%, 10%, 20%, 30% and 40% partial replacement of cement with ground clay brick (CB). From the test results, the chemical composition of the brick powder meets the standard requirements for pozzolanic material, with the SEM revealing an amorphous solid mass. The workability of the concrete reduces with increase in brick powder content. A significant improvement of the split tensile and compressive strength of the concrete was achieved at 10% cement replacement, after which a decrease in strength with increasing ground clay brick content was recorded. The use of ground clay brick of not more than 15% was recommended for concrete production.

This study reviews recent literature on the mechanical and durability properties of concrete incorporating seashells as partial or full substitutes for conventional materials. The study summarizes various contributions elucidating the various waste seashells utilized, the growing worldwide aquaculture production, seashell material preparation and treatment, chemical composition, physical properties, and different mechanical and durability test methods adopted by previous studies such as compressive strength, split tensile strength, flexural strength, modulus of elasticity, freeze-thaw resistance, water permeability, air content, chemical attack, carbonation, and weight loss. The study showed that mechanical properties indicate reductions of different percentages with increases in substitution ratio at 5% to 75%, compared to control mixes. However, relative increases in mechanical strength were recorded with the increase in curing age up to 90 days. Influence of seashells on durability properties varied across various durability tests at different seashell percentages. In a nutshell, the use of seashells in concrete production has a good effect, and further innovative research can solidify its utilization in the drive towards sustainable development.

Across the world, ballasted railway tracks are utilised extensively due to their cost efficiency, ease of drainage, and capacity to withstand cyclic imposed loadings from heavy trains. In spite of these benefits, the ballast is often considered as a flexible medium; as such, its continuous deterioration is largely disregarded. Geotechnical challenges such as ballast contamination in the form of particle fragmentation, deposition of weathered materials, upward pumping of clay and fines from underlayers, and coal intrusion have led to differential settlements and reduced drainability of tracks, thereby exacerbating track maintenance costs. This study reviews existing works of literature to expound on the mechanisms for ballast contamination and to highlight the fundamental parameters that guide the characterisation and performance evaluation of railway ballasts. The study shows that ballast fragmentation accounts for about 76% of commonly recorded contaminations, while it is also observed as the most critical to track stability. As such, a variety of indices and specifications for ballast gradation have been established worldwide to guide practice in ballast characterisation and performance evaluation. However, the mechanisms of ballast fragmentation and deterioration require further research to guide the improvement of contemporary guidelines, and mitigate the risk of abrupt track failures, especially in developing countries.

This study was carried out to review different types of available innovative construction materials. It was found that advancement in nanotechnology, use of mineral admixture, glass and plastic, biological materials, wood and other construction materials have contributed significantly to the growth of discovery and production of innovative construction materials. The implementation of some innovative construction materials, meets the requirements for sustainability, durability, reliability, safety, cost reduction, increasing quality, better mechanical and physical characteristics, flexibility in extreme conditions and locations, simple assembly and environmentally friendly. Construction materials used to carry out project consumed about 40% of the entire cost of the project in the construction industry. The success stories were recorded in the area of turning industrial and agricultural wastes to wealth. This reviewed paper will enrich the database for innovative materials entering the construction industry.