Double-curved textile reinforced concrete panels with tensile strain-hardening characteristics

The construction of buildings with fi-ee-form surfaces can be accompanied with relatively high costs. An innovative method to produce free-form surfaces in concrete is the application of double-curved precast panels produced with a flexible re-usable mould technique. Traditional placing of reinforcing bars to strengthen such panels causes practical problems, since only thin rebars are able to follow the movement of the mould during the production process. The use of flexible textile reinforcement can overcome such production limitations and effectively strengthens the panels. This paper discusses results of an experimental study on the behaviour of glass fibre textiles in concrete produced with a flexible re-usable mould. The movement of the mould during production might affect the position o f the textiles and thus the flexural capacity of the panels. The accuracy of the production method related to the position of the textiles was determined by measurements and indicated that the textiles were able to follow the deformation o f the mould. The friction of fibres inside a bundle not directly bonded with the mortar assured ductility of the panels. The proposed method to reinforce the panels proved feasible and a pronounced strain-hardening behaviour was obtained due to the action of the textiles.