ReStart

ReStart develops an eco-friendly floor system that combines steel, RAC, and timber, aiming to reduce material use, minimise waste, and lower carbon emissions.

The project at a glance

Start date:

01 Jan 2026
Duration in months:

30
Funding:

Fonds National de la Recherche (FNR), CORE (Junior)
Principal Investigator(s):

Qiuni FU

About

The construction industry is a major contributor to global resource consumption and CO₂ emissions, making it a prime target for circular economy strategies. This project, ReStart, introduces a novel hybrid slim floor system integrating steel, recycled aggregate concrete (RAC), and timber to enhance resource efficiency and reduce carbon emissions. The system utilizes puzzle-shaped composite dowels to connect RAC slabs with steel beams and incorporates timber as both permanent formwork and part of timber-concrete composite slabs. The overarching aim is to enable a reliable and cost-effective nonlinear design of slim composite beams using RAC, with particular attention to time-dependent effects due to creep and shrinkage. The research is structured into three main objectives: (1) characterizing the shear behaviour of steel-RAC composite dowels and developing a mechanics-based resistance model; (2) investigating the impacts of RAC creep on dowel performance and ultimate shear resistance under varying stress levels and loading sequences; and (3) assessing the strain-limited plastic resistance of composite beams using steel-RAC composite dowels at the cross-section and member levels, considering the influence of compact cross-sections with a steel T-profile and long-term effects. The project will deliver new knowledge and analytical tools — including a shear resistance model for steel-RAC composite dowels, reduction factor for long-term effects, a moment reduction factor at the cross-section level — along with design recommendations for strain-limited plastic (nonlinear) design of composite beams using composite dowels.