Comparative study of steel fibre-reinforced concrete and steel mesh-reinforced concrete at early ages in panel tests

Adoption of artificial lightweight aggregate in precast manufacture

“…8%). These findings are in line with those of Ding and Kusterle (1999), who did not show any significant trend relating to the ability of the steel fibres (using contents in the range of 40-60 kg/m 3 ) to improve the compressive strength of normal-weight concretes with curing periods of less than 24 h. This is perhaps due to the fact that, although the failure of the compressive sample essentially results from tensile and tensile-shear effects, which the SFR content should abate, it is likely that the failure of the cube samples is actually initiated by tensile strains and microcrack formation within the lightweight aggregate itself. The subsequent bond-cracking will then occur at the aggregate paste interface, with the macro-scale cleavage cracking thus being able to initiate and propagate in a manner that is largely independent of the need for the cracks to propagate through the cement matrix.…”

“…Furthermore, the failure type was much more akin to that of a two-way spanning slab than the 'pullout' cone observed for the previous samples ( Figure 5(d)). The amount by which the pull-out capacity of the anchor was improved by the addition of the 50 kg/m 3 steel fibre content is similar in magnitude to the improvement observed by Ding and Kusterle (1999) for the punching shear capacity of normal weight concrete slab elements, although these elements did incorporate a slightly higher fibre content (60 kg/m 3 ). It can therefore be concluded that the ability of steel fibre reinforcement to significantly influence the shear capacity of concrete within the early stages of strength development is similar for both normal and lightweight SPFA concrete variations.…”

“…Although a number of studies (Gau et al, 1997;Libre et al, 2011) have found steel fibre inclusion has a beneficial effect on the mechanical properties of lightweight concretes at a later stage of strength development, data with respect to its effect on concretes cured for periods of less than 3 d are extremely limited. However, the ability of this reinforcement type significantly to improve the early-age characteristics of more standard, normal-weight high-strength concretes has already been identified and demonstrated by research, such as that by Ding and Kusterle (1999). Their work investigated the effect of using various steel fibre dosages (20-60 kg/m 3 ) on the concrete's resulting compressive strength and punching resistance at the early-age time intervals of 10, 18, 30 and 48 h. This study is of particular interest, with a shear failure directly relevant (although inverted) to the expected anchor failure type.…”

“…In addition, the ability to ensure the effective compaction of the mix, as well as a suitable dispersion of fibres, was also stated to become difficult above this limit. A steel-fibre-reinforced concrete (SFRC) dosage level of 50 kg/m 3 was therefore selected, with this quantity, thus also allowing for a direct comparison with previous studies conducted in normalweight concretes (Ding and Kusterle, 1999).…”

Evaluación del comportamiento de vigas en voladizo de concreto reforzado con fibras ante la aplicación de cargas cíclicas

“…Subsequently, and as reported by Marmol (2010), scientific studies on this subject were undertaken by Griffith in 1920 andRomualdi in 1963. According to Nataraja et al (2000) Ding and Kusterle (1999) have stated that the compressive strength increase is insignificant; other authors, like Alfonso and Badillo (2011) have reported compressive strength increases over 20%.…”