Search

Cement clay interlocking (CCI) hollow bricks have been used as a construction material in many developed and developing countries. Many emerging and underdeveloped nations have utilised cement clay interlocking (CCI) hollow bricks as building materials. In India, Andhra Pradesh local makers prepare these cement clay interlocking (CCI) hollow bricks by simply mixing clay, cement, and sand in a traditional method, without following strict design criteria or rules. Previous research has demonstrated that the mechanical characteristics of CCI hollow bricks gathered from various locations in detailed manner respect to hand books on Civil Engineering as per Indian Standards. Bricks from one region had compressive strengths that were significantly lower than the other region Indian Community Standards. Various methods were employed in this investigation to enhance the mechanical characteristics of CCI bricks. New mix patterns were created with the use of sand, cement, and fly ash in this research paper. [ABSTRACT FROM AUTHOR]

AAC was introduced in India in 1970s. However, there were only three factories producing a total of less than 1 million m3/year till 2008. Post 2009, AAC blocks gained popularity due to their numerous advantages, including high strength, excellent insulation properties, fire resistance, sound absorption, and cost advantages over alternate walling materials. The use of AAC blocks has also been promoted by the Indian government's emphasis on sustainable and eco‐friendly building materials. The number of factories increased rapidly to over 150 factories with a cumulative capacity of over 25 million m3/year in 2022 (a growth of 25 times in nearly 15 years). Despite the rapid growth, the share of AAC in walling industry in India is still in the range of 5%–6%. There is still a lot of room for the industry to grow. AAC reinforced products have also been recently re‐introduced in India, though it is still at a very nascent stage and the share of AAC reinforced products in total AAC sales is less than 1%. More than 95% of AAC industry in India uses fly ash as the primary raw material and faced challenges initially to stabilize the design mix, due to variations in raw material characteristics. The rapid growth also resulted in improper implementation of standards and processes, during both production and application. The primary issue on the production side has been lower compressive strength and higher corner chipping. The main challenge on the application side has been improper techniques such as non‐usage of reinforcement beams and fiber meshes, which led to cracks in masonry subsequently. Now, the AAC industry is working together with applicators and researchers to overcome these challenges, in order to consolidate the gains and continue the rapid growth trajectory to become the preferred walling material. [ABSTRACT FROM AUTHOR]

Construction is a process of developing new ventures and is a never-ending activity. The aggregates are the raw materials, which constitute 70-80% in the concrete mixture. Every year, it is estimated that the construction industry in India generates about 10-12 million tonnes of waste annually. Concrete is the most versatile material which is used extensively in the construction field. There is a need to think of alternate materials because of the scarcity of natural aggregates. The use of this recycled coarse aggregate is mainly for two reasons: To decrease CO2 emission which is harmful to environment and to reduce the cost of construction material / cost cutting/reduce the budget of the construction. C&D waste can be reduced, re-used and recovered, dramatically reducing the dumping of demolished waste. The main purpose of recycling is to minimize the amount of waste to be deposited and to preserve natural resources. The present investigation is carried out for evaluation of properties of natural and recycled aggregate concrete. Pozzolanic materials like Fly Ash and Silica Fume are used as mineral admixtures for good workability and for better strength. Cement is replaced with 10% SF and 20% FA in design mix. RAC20 made with different grades of recycled aggregates of GA20, GA25, GA30, GA35 and GA40 with different replacements 50%, 75% and 100%. During mix proportion presoaking of aggregates is done before the mixing of concrete. Three stage mixing approach is adopted for the production of concrete. The density of concrete, compressive strength and water absorption of PC & RAC were determined at ages of 7 and 28 days. The results of compressive strength are found to be lower than target strength. With GA20 at 50% replacement, 95% of the target strength is achieved (27.55MPa). Strength could have achieved with increase in curing period. It is also concluded that the water absorption and density of RAC is lower than NAC. [ABSTRACT FROM AUTHOR]

Policy makers in India have realized the importance of facility for pedestrians and non- motorized vehicles in an urban infrastructure setup. This has resulted in increased utilization of construction materials like Portland cement and crushed stone, which are not environmentally friendly and sustainable. The current study presents the development of paver blocks for pedestrian facility using different wastes. Geopolymer concrete was synthesized by fly ash and recycled asphalt pavement aggregates for making of paver blocks. Paver blocks were produced in laboratory with recycled asphalt pavement aggregate replacement levels of 0%, 20%, 40%, 60% and 80% by weight of virgin coarse and fine aggregates. The developed paver blocks were tested for dimensions and tolerances, water absorption, compressive strength and abrasion resistance as per IS15658:2006 standard. The results of the laboratory study show that recycled asphalt pavement aggregates can be introduced into geopolymer matrix to produce paver blocks of desirable quality. Furthermore, its use in pedestrian facilities provides a new avenue for managing the excessive waste, which otherwise goes in landfills, incurring loss to the paving industry. Therefore, the proposed method can help decision makers to effectively utilize recycled asphalt pavement in paving industry with environment-friendly approach. [ABSTRACT FROM AUTHOR]

Sewage sludge (SS) management has been regarded as a serious environmental and health issue around the globe, especially in developing countries like India, mainly due to the lack of proper regulatory criteria, and appropriate engineering infrastructures. The present research work demonstrates the utilization of Fly Ash (FA) in varying percentages (with an interval of 10%) with SS as brick for sustainable building material with special emphasis on dimensional Effect. The impact of dimensional effect is measured using compressive strength behaviour for a stress rate of 14 MPa/min of two different sizes of brick i.e. D1 and D2 of sizes 7 × 7x7 cm3 and 2 × 2x2 cm3, respectively. Owing to the sintering effect, the maximum strengths of 4.02 MPa and 7.6 MPa are noticed for a composition of 60% SS+40% FA for D1 and 40% SS + 60% FA for D2, respectively. According to the Indian Standards (IS) 13757: 1993, an exhibited strength of more than 3.5 MPa by any brick composition enables it to be used as a common building brick. In general, due to the formation of triangular wedges, the D2 bricks exhibited better strength for any mixing ratio of FA and SS. The added benefit in our study was lower thermal conductivity (0.48 Wm−1K−1) of the prepared fired brick implying its better insulation property. Our study uniquely highlights the possible utilization of FA for stabilizing SS for sustainable substitution of natural clay fired brick. Future study may further investigate the compositional effect of FA on the thermal and thermodynamic attributes of the bricks. Image 1 • Pioneer study on bricks that visualizes dimensional effect along with mechanical properties. • 40–60% fly ash with sewage sludge satisfies Indian codal provisions as construction material. • Thermal conductivity of synthesized brick is lower than conventional fired clay bricks. • Dimensional effect significantly influences the compressive strength behaviour. [ABSTRACT FROM AUTHOR]