Imagine a world where construction is both durable and sustainable. Scientists are making this a reality by harnessing the power of rice husk ash (RHA) as a partial substitute for cement.
By leveraging machine learning techniques, they have developed prediction models for the compressive strength of RHA concrete, offering a cost-effective and efficient alternative to traditional methods.
“The study aimed to reduce the negative environmental impacts associated with the manufacturing of concrete. Environmentalists strongly believe cement must be replaced with a substance with a lower carbon footprint,” explained a member from the American University of Ras Al Khaimah (AURAK).
The construction industry, a major consumer of plastic and a significant contributor to greenhouse gas emissions is under increasing scrutiny for its environmental impact. Cement production, which emits large amounts of CO2, is a primary concern. The US Geological Survey (USGS) estimates that the annual global production of 4 billion tons of cement accounts for 7% of all CO2 emissions, with 0.9 tons of CO2 released per ton of cement produced.
To tackle this, the study utilized artificial intelligence (AI) to create predictive models for the compressive strength of RHA concrete. Unlike traditional methods, ML techniques efficiently map the relationship between input elements and response parameters, saving both time and cost.
The second phase of the research, conducted at AURAK, focused on the laboratory effects of using RHA as a partial cement replacement. Concrete mixtures with 5%, 10%, and 15% RHA by weight were tested for strength and durability in both fresh and hardened states at various ages.
The results showed that incorporating RHA enhances several properties of concrete, including later-age compressive strength, abrasion resistance, and moisture barrier characteristics. Additionally, it significantly reduces drying shrinkage, a key factor in concrete durability. This research promises more sustainable concrete production with reduced environmental damage.
“The outcomes of the test results point to the viability of using RHA in concrete for the production of economical, durable, and environmentally friendly concrete mixtures. Such mixtures represent an important step in the direction of sustainable construction practices,” said Roz-Ud-Din Nassar from the Department of Civil and Infrastructure Engineering at AURAK.
Innovative efforts like this are part of a broader trend toward sustainable construction. In 2020, engineers from Heriot-Watt University in Scotland launched Kenoteq, introducing the K-Briq made from up to 90% of building waste. This innovative brick emits only one-tenth of the CO2 of conventional bricks.
Similarly, in 2023, scientists in Panama discovered an insulation material from rice husks. They processed the husks and combined them with cellulose from used newspapers, adding Borax for fungal resistance and fire retardance, resulting in a sustainable insulation material.