Executive Summary : | The construction industry's significant contribution to greenhouse gas emissions has raised environmental concerns, leading to the development of environmentally friendly construction materials. Concrete is a prime example of this, as it is the most durable and reliable construction material. However, the production of Ordinary Portland Cement (OPC) is the second-largest contributor to CO2 emissions in the world, with an expected 25% increase in consumption in the next decade. Limestone, the primary source for OPC production, becomes a critical shortfall after 25 to 50 years. Cement production also emits nearly one ton of CO2 into the atmosphere, and energy consumption is a major challenge for sustainable development. To address this issue, the research aims to replace 65% of cement with ultra-fine fly ash with different concentrations of lime water in the production of very high-volume ultrafine fly ash concrete (VHVUFFAC). This will minimize CO2 emissions and utilize industrial waste. Corrosion of reinforced concrete structures is a major global problem, leading to significant repair and retrofitting costs. The quality of the skin/surface/cover zone of concrete significantly influences its durability. The type of formwork used during construction significantly affects the performance of the surface skin. Controlled permeable formwork (CPF) is an active technique used to improve the quality of the surface skin of concrete. The CPF system consists of a textile liner that allows water and entrapped air to drain out from the near surface concrete while retaining cement and other fine particles. This mechanism lowers the water-to-cement ratio, enriches cement content, and decreases surface porosity in the cover zone, creating a uniform surface without blowholes, pinholes, and surface blemishes. |