Pullout Behavior of Recycled Waste Fishing Net Fibers Embedded in Cement Mortar.

Jun Kil Park,Dong Joo Kim,Min Ook Kim

doi:10.3390/ma13184195

Abstract

In this study, recycled waste fishing net (WFN) short fibers were proposed to be used as short fiber reinforcements. The pullout resistance of WFN short fibers embedded in cement mortar was investigated by conducting fiber pullout tests. Three types of WFN short fibers and two types of commercial polypropylene (CP) fibers were investigated. To quantitatively compare the pullout resistance of WFN short fibers and CP fibers, pullout parameters, including peak pullout load (peak bond strength), peak fiber stress, slip at peak load, and pullout energy (equivalent bond strength) of the pullout specimens, were analyzed. In addition, the analysis of fiber images, captured by using a stereoscopic digital microscope, before and after pullout tests, elucidated the different mechanisms of fiber pullout corresponding to the type of fibers. The bundled structures of the WFN fibers generated mechanical interaction between fiber and matrix during fiber pullout; consequently, they produced higher bond resistance and more damage on the surface of fibers after the pullout. Therefore, the bundled WFN fibers showed comparable pullout resistance with CP fibers.

Highlights

Fiber-reinforced cement composites (FRCCs) have been developed since the 1970s to prevent the brittle failure of cement composites [1,2], and various types of reinforcing fibers have been developed to enhance the tensile strength and toughness of cement composites [3]
FRCCs are still more expensive than normal concrete; the use of FRCCs is limited to specific structures, such as high-rise buildings, protection facilities, tunnel lining, and structural foundations [11,12]
This study proposed to use waste fishing net (WFN) short fibers as short fiber reinforcements instead of commercial fibers because the use of WFN would be beneficial for reducing the costs and for preventing environmental pollution

Summary

Introduction

Fiber-reinforced cement composites (FRCCs) have been developed since the 1970s to prevent the brittle failure of cement composites [1,2], and various types of reinforcing fibers have been developed to enhance the tensile strength and toughness of cement composites [3]. Synthetic fibers generally have lower tensile strength and modulus of elasticity than steel fibers; they have excellent corrosion resistance [10]. The diameter of micro-fibers is between and μm, and the length is between and size of fibers. The diameter of micro-fibers is between 5 and 100 μm, and the length is between 55 and 30 mm mm [23],. Micro-fibers are generally added to cement mortar to enhance the tensile is between 30 and 60 mm [24]. Micro-fibers are generally added to cement mortar to enhance the strength, whereas macro-fibers are effective for the ductility of cementitious composites [25]. Tensile strength, whereas macro-fibers are effective for the ductility of cementitious composites. Micro-fibers are generally added to cement mortar to enhance the strength, whereas macro-fibers are effective for the ductility of cementitious composites [25]. [25].

Methods

Discussion

Conclusion