Silvio Weiland

Textile Reinforced Concrete for Flexural Strengthening of RC-Structures-Part 2: Application on a Concrete Shell

The first practical application of the innovative strengthening method using textile reinforced concrete was carried out in October/November 2006 in the retrofit of a reinforced-concrete roof shell structure at the University of Applied Sciences in Schweinfurt, Germany. Since textile-reinforced concrete had not yet been standardized as a construction material, a single “special-case” technical approval was sought from and granted by the appropriate authorities for this particular application of textile reinforced concrete. This strengthening method entailed the layer-by-layer application of three layers of fine-grained concrete and textile fabric comprising 800 tex carbon rovings onto a rough, sandblasted concrete surface. The resulting strengthening layer has a thickness of only 15 mm (0.6 in.) and extended the roof structure’s service life.

Flexural Strengthening of RC Structures with Textile-Reinforced Concrete

Textile-reinforced concrete (TRC) is a high-performance composite in which technical textiles made of high-performance fibers are embedded in a fine-grained concrete matrix. Textile-reinforced concrete extends concrete applications to completely new fields. Besides slender new concrete elements, strengthening of already-existing concrete structures by thin textile-reinforced concrete layers is possible. This type of strengthening noticeably increases both the ultimate load-bearing capacity and serviceability of reinforced concrete structures. This aspect is shown in the present paper using experimental results of TRC-strengthened slabs.

Textile-Reinforced Concrete for Flexural Strengthening of RC-Structures—Part 1: Structural Behavior and Design Model

The use of technical textiles to reinforce concrete (i.e., textile reinforced concrete [TRC]) extends into entirely new areas of application. The thick concrete covers, as required for steel reinforced concrete, are no longer needed due to the corrosion resistance of textile materials. Slender structural members with thicknesses as small as 10 mm (appr. 4 in.) are possible. Additional characteristic features of textile reinforcement include two-dimensional planar characteristics, as well as ease of deformability and adaptability to complex and curved geometries. This can be exemplified by a pedestrian bridge built of TRC. Various geometric forms, such as slabs, beams, T-beams, shells, and columns can easily be strengthened using TRC. Dimensioning of elements and structures using TRC requires detailed knowledge of the load-bearing behavior of this composite material. Indeed, such behavior resembles that of steel reinforced concrete; however, this behavior is more heavily influenced by the bond between the textile reinforcement and the fine concrete, as well as the bond between filaments within the textile reinforcement. Minimal thicknesses also make it possible to strengthen existing concrete structures using TRC. Such strengthening increases both the ultimate load bearing capacity, as well as the serviceability, of the structure. Experimental results of strengthened slabs and beams, as well as a design model for flexural strengthening, is presented in this paper.

Strengthening of RC Structures with Textile Reinforced Concrete (TRC)

Strengthening by textile reinforced concrete noticeably increases both the ultimate load bearing capacity as well as the serviceability such as deflections, crack widths and crack spacing are reduced. This paper will give an overview of the ongoing research work with this new composite material Textile Reinforced Concrete (TRC).