Simulation and test of flexural performance of polyvinyl alcohol-steel hybrid fiber reinforced cementitious composite

Abstract

The flexural performance of polyvinyl alcohol-steel hybrid fiber reinforced engineered cementitious composite with characteristics of low drying shrinkage special focus on impacts of steel fiber content and matrix strength has been investigated in both experimental and theoretical aspects in this paper. Four matrix types with water to binder ratio of 0.25, 0.35, 0.45, and 0.55 and three additional steel fiber contents in the composite with polyvinyl alcohol fiber content of 1.7% in volume were used in the test program. The experimental results show that cracking and flexural strength of the composites are increased with the addition of steel fiber. This enhancement becomes more and more pronounced with decreasing of water to binder ratio of the composites. Meanwhile, fracture mechanics-based flexural model is used to simulate the flexure performance of the polyvinyl alcohol -steel hybrid fiber reinforced engineered cementitious composite with characteristics of low drying shrinkage. The model results show that a double peak load is expected of the composites under bending load. The first peak is controlled by the fracture toughness of matrix or cracking strength of matrix, and the second peak is governed by the fiber bridging. The effect of addition of steel fiber in engineered cementitious composite with characteristics of low drying shrinkage on the first peak is unapparent. The impact of steel fiber on the second peak is significant. This enhancement of additional steel fiber gradually decreases with the decrease of water to binder ratio of the matrix, which coincides well with the experimental findings. The test results are compared to the model and reasonable agreement is found.

Static and dynamic mechanical properties of eco‐friendly polyvinyl alcohol fiber‐reinforced ultra‐high‐strength concrete

“…With the development of structural engineering, high‐strength concrete (HSC) or ultra‐high‐strength concrete (UHSC) characterized by a lower water‐to‐binder ratio, addition of fine and active admixtures (i.e., silica fume, fly ash and ground granulated blast furnace slag, and so on) as well as special curing technologies is proposed and designed by a large number of researchers and engineers . However, it has been widely recognized that concrete, especially HSC or UHSC, is a typical brittle material, and after its first cracking in tension, localization of deformation will occur immediately followed by decreasing load . Resultantly, the durability and life of concrete structures are deteriorated seriously.…”

“…On the one hand, a class of high‐performance fiber‐reinforced cementitious composite, called engineered cementitious composite (ECC), has been micromechanically developed to provide an ultimate strength higher than the first cracking strength . The typically extreme tensile strain capacity of ECC can be more than 2% while only a moderate amount of fibers (generally less than 2% in fraction) is required .…”

“…1,2 However, it has been widely recognized that concrete, especially HSC or UHSC, is a typical brittle material, and after its first cracking in tension, localization of deformation will occur immediately followed by decreasing load. 3,4 Resultantly, the durability and life of concrete structures are deteriorated seriously. To overcome these shortcomings and enhance mechanical performance of concrete, randomly distributed fibers have been introduced as a reinforcement material during the last few decades.…”

“…On the one hand, a class of high-performance fiberreinforced cementitious composite, called engineered cementitious composite (ECC), has been micromechanically developed to provide an ultimate strength higher than the first cracking strength. 3,4,7,8 The typically extreme tensile strain capacity of ECC can be more than 2% while only a moderate amount of fibers (generally less than 2% in fraction) is required. 7 Since 1990s, the mechanical and durability-related performances of ECC are explored and discussed at material and structural component levels, such as in the works of Alrefaei et al, 9 Li et al, 10 Bezerra et al, 11 Lepech et al, 8 Lee et al, 7 Xu et al, 12 Ahmed and Mihashi, 13 Li et al, 3 Zhang et al, 4 and Li et al 14 Moreover, ECC has been applied in some engineering practice cases.…”

Mechanical Attributes of Uniaxial Compression for Calcium Carbonate Whisker Reinforced Oil Well Cement Pastes

“…Since the distance was smaller, the thickness of the weak link of the fiber-matrix layer was thinner which indicated that the fiber could adhere the matrix with much fastness; this meant that the mechanical strength was well developed. As assumed, the CaCO 3 whiskers were well dispersed in the three-dimensional direction in the cement paste and the equation of the average distance of the CaCO 3 whiskers was shown as follows [24][25][26]:…”