A Pavement Repair and Strengthening System (PRSS) is under development at Coventry University offering a pioneering approach to road rehabilitation. It aims to develop a bonded polymer modified overlay with the superior mechanical properties of concrete and the special workability of asphalt to facilitate fast construction by asphalt paving machinery. The utilization of the residual structural potential of the existing worn pavement makes it more sustainable in both environmental and economic terms as an alternative to the wholesale reconstruction of the existing structural concrete pavement. The special concrete mix was optimized by a newly developed method highlighted in this article to provide sound mechanical properties and practical construction solutions for fast repairing techniques. The problems associated with achieving structurally effective bonded concrete overlays, such as reflective cracking due to flexure failure, shear failure and delamination were examined in detail by a considerable number of rigorously conducted laboratory experiments. This paper launches the new mix design method, the geometrical size effect and the efficiency of steel fibre on the structural behaviour of the roller compacted, polymer modified concrete. The new mix design highlighted in the article is the key to achieving good mechanical performance with rapid construction technologies. The investigation of flexural resistance disclosed the size effect on flexural strength in the PMC (Polymer Modified Concrete) beams. A comparison was made between the roller-compacted PMC and the conventional PMC regarding the behaviour of the steel fibre in crack control. A series of tests were carried out on PMC beams with 1%, 1.5% and 2% of steel fibres to evaluate its impact on the shear, splitting tensile, flexural and compressive strength levels. The same PMC was experimentally tested at early ages and proved to have very high strength at an early stage. This can minimise the duration of traffic control and be beneficial for both highways authorities and road users. The investigation on the material and the structural performance will hopefully permit pavement engineers to further exploit its advantages such as economy, convenience and long, maintenance free life that PRSS could offer.
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