Abstract

A technical, economic and environmental analysis over the road life cycle shows that concrete pavements are a sustainable paving alternative. However, the election of concrete as material for pavements is limited when only the construction costs are considered in the analysis. There is a continuing development of technology in order to reduce the costs of concrete pavements while maintaining the good performance and durability. Early-Entry Saw-Cutting (EESC) consists of a shallow cut (up to 30 mm depth) that allows a faster construction of Jointed Plain Concrete Pavements (JPCPs) because the joints can be cut just 3-5 hours after concrete placement. In addition, EESC is useful to avoid repair costs for random cracking because it relieves internal concrete stresses. Although EESC has become more accepted, especially in U.S.A, there are some concerns regarding to its influence on the JPCP performance. The objective of this paper is to evaluate the influence of the saw-cutting method on the JPCP performance. For that, a modelling of the activation of transverse joints and their crack width value is made. The modelling takes into account the cut depths of the EESC and the conventional saw-cutting method when they are applied to traditional and short slab JPCPs. In addition, the Load Transfer Efficiency (LTE), related with the crack width, and representative for the JPCP performance is estimated using the experimental verification of the finite-element software EverFE. Finally, practical experiences of JPCP projects in similar conditions as assumed in the modelling are considered in the evaluation, including fibre-reinforced concrete (FRC). It was concluded that EESC is effective to avoid random cracking but special measures need to be taken to evade higher stresses in the JPCPs that are not considered in the design and will negatively influence the JPCP performance. In short slabs, for the analysed conditions, a Relative Joint Depth (RJD) <= 25% results in LTE <= 52% and uncracked joints, therefore longer slabs than the designed ones. In traditional JPCPs a RJD <= 25% results in a very low LTE (<= 30%).