Influence of the Fiber Volume Content on the Durability-Related Properties of Polypropylene-Fiber-Reinforced Concrete

Abstract

Polypropylene-fiber-reinforced concrete impacts the early shrinkage during the plastic stage of concrete, and the fiber volume content influences the durability-related properties of concrete. The purpose of this paper was to investigate the influence of fiber volume content on the mechanical properties, durability, and chloride ion penetration of polypropylene-fiber-reinforced concrete in a chloride environment. Tests were carried out on cubes and cylinders of polypropylene-fiber-reinforced concrete with polypropylene fiber contents ranging from 0% to 0.5%. Extensive data from flexural strength testing, dry–wet testing, deicer frost testing, and chloride penetration testing were recorded and analyzed. The test results show that the addition of the fiber improves the failure form of the concrete specimens, and 0.1% fiber content maximizes the compactness of the concrete. The flexural strength of specimen C2 with 0.1% fiber shows the highest strength obtained herein after freeze–thaw cycling, and the water absorption of specimen C2 is also the lowest after dry–wet cycling. The results also indicate that increasing the fiber volume content improves the freeze–thaw resistance of the concrete in a chloride environment. Chlorine ions migrate with the moisture during dry–wet and freeze–thaw cycling. The chlorine ion diffusion coefficient (Dcl) increases with increasing fiber content, except for that of specimen C2 in a chloride environment. The Dcl during freeze–thaw cycling is much higher than that during dry–wet cycling.

Review on the Durability of Polypropylene Fibre-Reinforced Concrete

“…e interfacial transition zones between PPF and cement overlap each other due to the poor dispersion of PPF in concrete, leading to the porosity of concrete, as shown in Figure 9. Wang et al [61] studied the freeze-thaw cycle resistance of concrete with different PPF fibre contents (0.1%, 0.3%, and 0.5%), which were immersed in 3.5% NaCl solution. e rates of mass and dynamic elastic modulus decrease of concrete after freeze-thaw cycle decrease with the fibre content.…”

Natural and Artificial Fibre Reinforced Concrete: A State-of-art Review

“…In the freeze-thaw test, the specimen with 0.5% PPF shows better resistance against salt freezing. However, in a chloride environment, the specimen with 0.1% PPF performs better in the freezethaw and wet-try tests (13). Jia et al (14) confirmed that the interfacial adhesive strength between the cement matrix to PPF was increased when PPF was mixed with Micro-silica (MSi), which acts as a hydrophilic modifier.…”

Birnbaum-Saunders Durability Life Prediction Model of Site-Exposed Concrete in the Saline Soil Area

“…However, due to the long period of outdoor durability tests and data collection difficulty, the current research on the corrosion degradation mechanism and erosion degradation analysis of concrete is mainly based on indoor tests. It mainly considers the main damage factors of structural concrete materials in a certain corrosive environment, designs the accelerated stress level on this basis to obtain the degradation process of structural concrete materials in a relatively short period [8,9], and explores the damage mechanism [10,11] to propose the ways and methods to improve the durability [12,13]. For example, Chen considered the electrochemical coupling effect and moisture convection effect on the transport of chlorine in unsaturated concrete.…”

“…Zhang mainly proposed a coupling model and reduction function for the impact of sulfate and chloride on reinforced concrete durability, as well as quantitatively analyzing the impact of sulfate erosion on chloride ion migration from the perspectives of solution concentration, soaking time, curing time, water binder ratio, and aggregate [16]. On the one hand, these findings provide a good reference and enlightenment for the durability design of reinforced concrete in harsh environments [12][13][14][15][16]. On the other hand, although the indoor accelerated test has many advantages in simulating concrete deterioration, such as a short test period, convenient testing, and few influencing factors, it still has a particular gap with the concrete degradation process in the actual service environment, and it cannot completely achieve the same degradation as the real service environment.…”