New insights into the splitting failure of textile-reinforced concrete

摘要

Textile-reinforced concrete is ideally suited to complement ordinary steel-reinforced concrete, as the use of textile reinforcement with its outstanding mechanical properties and durability allows the construction of slender, lightweight structural elements. Despite the increased interest in this innovative composite material making it a subject of various research projects carried out during the past two decades, questions regarding its specific properties remain. An economically driven trend towards using rovings with a high yarn count and coated with a stiff impregnation material has surfaced in recent years, which has led to an increased occurrence of splitting failures in textile-reinforced concrete elements. This paper describes investigations aimed at clarifying the theoretical background of this failure mode. Preliminary experimental studies were carried out to identify and quantify the impact of several influencing parameters thought to be responsible for inducing longitudinal cracking in textile-reinforced concrete. In subsequent numerical computations with a particular focus on bond behaviour, the stress distribution in the concrete during fibre strand pull-out was visualised. The analysis of the different investigations carried out by the authors showed that the geometric characteristics of the fibre strands have a significant influence on bond behaviour and particularly on splitting failure in textile-reinforced concrete.