Mechanical Properties of Hybrid Ultra-High Performance Engineered Cementitous Composites Incorporating Steel and Polyethylene Fibers.

Yingwu Zhou,Feng Xing,Lili Sui,Bin Xi,Kequan Yu

doi:10.3390/ma11081448

Yingwu Zhou, Feng Xing + Show 3 more

Open Access

https://doi.org/10.3390/ma11081448

Copy DOI

Abstract

This paper presents the authors’ newly developed hybrid ultra-high performance (HUHP) engineered cementitious composite (ECC) with steel (ST) and polyethylene (PE) fibers. From this point on it will be referred to as HUHP-ECC. The volumes of steel and PE fibers were adjusted to obtain different mechanical properties, including compressive strength, tensile, and flexural properties. We found that tensile and flexural properties, including bending strength and ductility indexes, increased with higher PE fiber amounts but reduced with the increased ST fiber volume. Notably, the compressive strength had the opposite tendency and decreased with increases in the PE volume. The ST fiber had a significantly positive effect on the compressive strength. The fluidity of HUHP-ECC improved with the increasing amount of ST fiber. The pseudo strain-hardening (PSH) values for all the HUHP-ECC mixtures were used to create an index indicating the ability of strain capacity; thus, the PSH values were calculated to explain the ductility of HUHP-ECC with different fiber volumes. Finally, the morphology of PE and ST fibers at the fracture surface was observed by an environmental scanning electron microscope (ESEM).

Highlights

The engineered cementitious composite (ECC) was designed based on the micromechanics theory [1,2,3] and featured with the strain-hardening behavior
Values for all the hybrid ultra-high performance (HUHP)-ECC mixtures were used to create an index indicating the ability of strain capacity; the pseudo strain-hardening (PSH) values were calculated to explain the ductility of HUHP-ECC with different fiber volumes
The morphology of PE and ST fibers at the fracture surface was observed by an environmental scanning electron microscope (ESEM)

Summary

Introduction

The engineered cementitious composite (ECC) was designed based on the micromechanics theory [1,2,3] and featured with the strain-hardening behavior. The conventional polyvinyl alcohol fiber (PVA) ECC has a tensile strain capacity of more than 3% and a maximum tensile strength between and 6 MPa, with a fiber volume fraction of no more than 2% [4,5,6]. The tensile strain capacity of ECC is about 300 to 500 times larger than that of normal concrete [1,3]. Researchers (including the authors) used ultra-high molecular weight polyethylene fiber (UHMWPE or PE for short) to develop ultra-high performance engineered cementitious composites (UHP-ECC) [8,9,10,11]. The UHP-ECC already has vast development prospects in all kinds of civil engineering applications

Methods

Results

Conclusion