Geometrical characteristics and efficiency of textile fabrics for reinforcing cement composites (original) (raw)

Fabric structure and its reinforcing efficiency in textile reinforced cement composites

Composites Part A: Applied Science and Manufacturing, 2003

In polymer matrices reinforced with fabrics, the effectiveness of the reinforcement is reduced when the yarns do not maintain a straight geometry. In cement composites, this concept may not be adequate since the nature of the interaction between the cement matrix and the fabric and its individual yarns is more complex, as concluded from pullout tests. The present paper discusses the bulk properties and geometrical characteristics of textile fabrics that need to be considered in order to predict the performance of cement composites reinforced with textile fabrics. It was found that the geometry of a given fabric could enhance the bonding and enable one to obtain strain hardening behavior from low modulus yarn fabrics, due to the special shape of the yarn induced by the fabric. On the other hand, variations of the geometry in a fabric could drastically reduce the efficiency, resulting in a lower strengthening effect of the yarns in the fabric, relative to single yarns not in a fabric form. Therefore, in cement composites the fabrics cannot be viewed simply as a means for holding together continuous yarns to be readily placed in the matrix, as is the case in composites with polymer matrix.

Effects of Woven Fabric Geometry on the Bonding Performance of Cementitious Composites

Advanced Cement Based Materials, 1998

The effect of the geometry of woven fabrics on the bond between monofilament polyethylene yarns and cement matrix was studied in the present work. The fabrics were all plain weave, with varied fills density: 5, 7, or 10 fills per cm; the warps' density was kept constant at 22 warps per cm. The interfacial bond was evaluated by pullout tests. To characterize the influence of the fabric's geometry on bond performance, the influence of different parameters of the fabric's geometry that may affect bond were separated: (1) pullout of a single crimped yarn untied from the fabric to characterize the influence of the shape of the individual crimped yarn; (2) pullout of a single yarn from free fabric (not embedded in the cement matrix); and (3) pullout of a yarn from a fabric embedded in the cement matrix. Straight yarns were also tested for comparison. It was found that the woven fabric provided a considerably better bond to the cementitious matrix than the bond of a single straight yarn. The crimped geometry of the yarn in the fabric was found to have a significant influence on increasing the bond between the woven fabric and the cementitious matrix.

Effect of fabric material and tightness on the mechanical properties of fabric–cement composites

This study shows the effect of fabric tightness and fabric material on the mechanical properties of fabric–cement composites. Six fabric designs from the same fabric material were used. These fabric designs are vary in the specific tightness. Also, three fabric materials with the same fabric design were used in this work. Different sets of specimens were made, after that these specimens were tested on tensile and bending testing machines. It was found that the mechanical properties of the composite materials were influenced by the length of the warp thread float, i.e. the longer is the yarns float in the fabric, the greater is the tensile strength properties of the reinforced fabric, its construction and the material of the reinforced fabric. Therefore, it is recommended to use fabric with yarns with higher tenacity in the direction of the application of load and with either long float or minimum number of intersections.

Fabric-structural Parameters Affecting the Mechanical Properties of Fabric-cement Composites

Journal of Engineering Research and Reports

This research work studies the effects of fabric structure on the mechanical properties of fabric cement composites. Seven fabric structures from the same fabric material were used. In this work different sets of specimens were made with different fabric layers after that these specimens were tested on tensile, bending and compression testing machines. It was found that the mechanical properties of the composite materials were influenced by the properties of the reinforced fabric. Fabric tensile strength, which is determined by the fabric's structure, construction, and the number of reinforced fabric layers, is the key factor influencing both tensile and flexural strength of the cement composites. Additionally, when the number of fabric layers increases, some attributes of composites, such as tensile and bending strength, increase while compressive strength decreases.

Tensile behavior of textile: Influence of multilayer reinforcement

2012

The interest in the use of textile fabrics as reinforcement for cement based composite materials has been increasing in the last few years. Textile cementitious composites show improved tensile performances; as a matter of fact in addiction to a considerable peak strength, these composites show a strain hardening behaviour even when the reinforcing yarns have a low modulus of elasticity. This was explained by the enhancement in bonding due to the mechanical anchoring provided by the non-linear geometry of the individual yarn within the fabric.

Durability study of textile reinforced cementitious composites with low fiber volume fraction

2017

Steel reinforced concrete is the most popular material for modern building solutions. One of its well-known issues is the high susceptibility of steel to corrosion. In recent times, research has focused on the replacement of steel rebars in reinforced concrete. The use of textiles has gained a strong interest in this context. These textiles can be impregnated into mortars or concrete and are not sensitive to corrosion. However, for practical applications, an analysis of their durability performance and long term behavior is necessary.In this paper textile reinforced cementitious composites (TRCs) with a low fiber volume fraction are studied. To study their long term behavior, the specimens were aged by performing heatrain and freeze-thaw cycles, according to EN 12467. After ageing, the structural performance of the aged specimens was compared to reference specimens by means of a uniaxial tensile test. To compare the structural behavior quantitively, a focus was placed on the mechani...

EFFECT OF PROCESSING ON MECHANICAL PROPERTIES OF TEXTILE - REINFORCED CONCRETE

The objective of this study was to investigate use of pultrusion technique as a cost-effective method for the production of thin-sheet fabric-reinforced cement composites. Cement based composites were developed with different fabric types using cast (hand lay up) process and pultrusion (impregnated) methods. Knitted fabric made from low modulus polypropylene (PP) fabric, woven fabric made from low modulus polyethylene (PE), and bonded glass meshes were used. Tensile and pullout tests as well as SEM observations were used to examine the mechanical, bonding and microstructure properties. It was observed that the processing method significantly affects the bond as well as the tensile performance of the composite. The best performance was achieved for the PP pultruded composites.

Tensile behavior of fabric cement-based composites: pultruded and cast

2007

There is a growing interest in the use of fabrics as reinforcements for cement composites due to their superior performance in comparison to other cementitious composites. This paper compares the effects of two processing methods, casting and pultrusion, on the tensile properties of fabric-cement composites. Four fabric types were used, including bonded glass mesh, woven polyvinylalcohol, woven polyethylene, and warp knitted weft insertion polypropylene.