Bio-based insulating concrete : environmental assesment, aging and recyclability – BELIEVER

Biobased building materials are a promising way of valorizing agricultural by-products, with many environmental benefits (local availability, renewability and biogenic carbon storage potential). The use of these materials, encouraged by public policies, represents a lever for reducing the major environmental impact of the building sector. In France, the new RE2020 environmental regulations now include an LCA approach. In this context, the BELIEVER project aims to propose more precise environmental assessment tools adapted to biobased construction materials such as hemp concretes. Achieving this main objective implies acquiring new knowledge concerning the ageing mechanisms of hemp concretes and their consequences on their microstructure and macroscopic properties, and demonstrating the feasibility of recycling hemp concrete waste. The proposed scientific approach is based on the interdisciplinary and complementary expertise and tools of the BELIEVER project consortium, covering the plant, the mineral matrix, the interface and the environmental assessment of the material's properties over time. The scientific objectives are: i) To understand and model the ageing mechanisms of hemp concretes at the microstructural scale, and their consequences on macroscopic properties. ii) To assess the potential of recycling construction site waste and deconstruction products for the formulation of durable, efficient hemp concretes. iii) To assess the carbon flows and environmental impacts, taking into account the specific characteristics of biobased building materials in general, and hemp concrete in particular, in terms of carbon storage, changes in properties over time and end-of-life scenarios.