Self-compacting mortars and concretes for horizontal structures are cementitious mixtures that are both fluid and homogeneous, with the particularity of flowing under the effect of their own weight. Thanks to their homogeneous texture they offer the possibility of achieving good quality of finishing and many such advantages become the reason for their applications especially in slabs and floors. However, self-compacting mortars or concretes show considerable shrinkage and cracking problems when used in floors and slabs (Weiss et al., 1998). Because of their large moisture exchange surfaces, the floor screeds are subjected to significant drying effects and in particular plastic shrinkage. If the movements are restrained, the risk of cracking is high. In this respect the use of fibers is a good alternative to using reinforcement bars and welded wire mesh. Indeed on site a clear decrease in cracking caused mainly by the shrinkage can be observed as soon as the fibers are incorporated in the screed. This study is conducted to demonstrate the effectiveness and the effects of glass fibers on the control of cracking phenomena due to shrinkage by determining their mechanisms of action at young age. The study is carried out in two parts: Firstly, free shrinkage behavior is analyzed in the fiber reinforced floor screed. Secondly, the restrained behavior at young ages using recently developed uni-axial tensile testing machine is investigated.

The use of fibres as an alternative to steel welded wire mesh and rebars is today an extensive practice for the reinforcement of concrete floors. But although the use of fibres as the only reinforcement for slabs-on-ground can lead to a highly improved productivity, simpler execution, increased durability, etc., the proportion of fibre-reinforced concrete (FRC) solutions is still very limited with respect to its potential.

This paper presents the application of the fib Model Code 2010 (MC2010) to the design of a glass-macro-fibre-reinforced concrete slab-on-ground, using finite element analysis and nonlinear fracture mechanics, easily enabled by the material constitutive equations proposed by the MC2010. The relatively high post-cracking performance provided by glass macro-fibres at low crack openings is especially convenient for highly indeterminate structures such as floors, where the ultimate capacity involves very low crack openings (usually below 0.3 mm). The MC2010 approach allows these specific material and structural behaviours to be taken into account, leading to competitive FRC floor designs.

The ACI Committee 544 on fibre-reinforced concrete (FRC) has been involved in development and dissemination of technical information for nearly a half century. A key advantage in using FRC is the reduction in construction time compared to the traditional reinforcing bars or welded wire mesh. Application areas for FRC have extended to areas where high early strength and ductility are important and include pavement, shotcrete and structures such as bridge deck slabs, or rock slide stabilization. In these cases, the material properties must be measured using experimental test data obtained from an experimental program. Test results must be analysed in order to obtain effective stress strain responses that can be incorporated in analytical, or computer simulation. A list of examples including wall panels, hydraulic structures, airport pavements, and industrial floor overlays are described. To maintain integrity without collapse, such structural elements need to be designed with proper material models and analysis tools discussed.

The purpose of this report is to compare the corrosion resistance of several proprietary combinations of stucco and wire reinforcing mesh (lath) to enhance corrosion protection against chloride environments. The lath is produced by spot welding galvanized steel wire and was tested pre-welding, post-welding and after a post-weld chromate treatment. The effect of the weld joint and the chromating on the initial rapid corrosion, typical of zinc embedded in cement-based materials, was first investigated. Despite the loss of zinc at the welds, there was little difference in corrosion rates of the non-welded and welded specimens. The chromating, however, was found to be highly beneficial in eliminating the initial rapid corrosion. A second set of tests investigated the comparative corrosion behavior of the lath in OPC-based stucco and a commercial calcium-aluminate-based stucco (Stucco A) in chloride solution. The study showed the Stucco A to provide less protection than the OPC stucco. Addition of lime to Stucco A, which is not recommended by the manufacturer, resulted in greater corrosion protection.

LCPC (Central Laboratory for Roads and Bridges, a French public research laboratory) has developed for five years a new concept of concrete pavement. It is based upon the following ideas: - High-Performance Concrete shows unique qualities with regard to pavement applications, like high tensile strength, durability, freeze-thaw resistance, abrasion resistance and prevention of steel corrosion; - but economy does not promote the use of HPC in conventional pavement, since the gain in flexural strength leads to a decrease in slab thickness, which does not compensate the increase of material unit cost (i.e. the cost per unit surface increases when replacing normal- by high-strength concrete); - HPC qualities are mostly desirable at the top surface of the pavement. Therefore, HPC Carpet consists in a thin, 60-mm HPC wearing course, reinforced by a welded wire mesh, cast upon a conventional concrete (or cement-treated material) structural layer. Thanks to a complex of polymer and geotextile, there is no bond between the two layers, so that reflexive cracking from the base to the course layer is avoided. However, cracking due to traffic loads is permitted in both directions, the dense reinforcement being supposed to maintain the course layer integrity. The paper will give an overview of this research, which encompassed design calculations, thermal instability verification, fatigue tests on a 10-m full scale model and an experimental construction site near Lyon (France). Here, a 120-m long test section has been built in 2003, and is currently submitted to a heavy truck traffic. To date, the behavior is excellent. In conclusion, the economical potential of this new concept will be highlighted. Rehabilitation of old concrete pavements – where slabs are partly cracked, with moderate rocking – appears as a promising market.