Effects of self-cementing properties on the performance of a sustainable capillary barrier cover system by using recycled concrete aggregates

In supporting the UK Government to fulfil its targets on carbon emissions and environmental protection, there is an increasingly strong emphasis on recycling and reuse of construction waste in civil engineering. In this study, a sustainable capillary barrier cover system incorporating Recycled Concrete Aggregates (RCA) is proposed to be developed. Fine recycled concrete aggregates (FRC) and Coarse Recycled Aggregates (CRC) will be used to form the fine-grained and coarse-grained soil layers of a two-layer capillary barrier (CCBE). According to previous studies, the permeability of compacted RCA decreases while the strength increases over time due to the self-cementing properties of compacted RCA.

In this study, the primary objective is to investigate the key hydro-mechanical mechanisms that influence single compacted RCA layers and hence assess the performance of a sustainable RCA based capillary barrier cover system. A range of laboratory tests, including 1D soil column tests and 2D flume tests, will be carried out along with numerical simulation and field testing to monitor the long-term performance of the sustainable cover system.

The expected deliverable from this study is an advanced hydro-mechanical model which can be used to analyse compacted RCA elements taking into consideration: (i) the self-cementing characteristics of RCA, (ii) the mechanisms of water infiltration in a RCA based sustainable capillary barrier cover system and (iii) optimum combinations of soil materials and layer thickness for the barrier system under various climate conditions.

A successful outcome of this work is expected lead to improved design methods for barrier systems for structural foundations and landfill structures subjected to dynamic loading and seismic effects.

Funding Notes

there is no funding for this project