Degradation of basalt FRP bars in alkaline environment

Abstract

This paper investigates the degradation of basalt fiber reinforced polymer (BFRP) bars used for concrete construction in an alkaline environment. The relationships between tensile strength, elastic modulus, shear strength and moisture absorption rate over time are analyzed using a tension test, short-beam test and moisture absorption weighting. The tensile strength degradation of BFRP bars was further compared with that of Glass FRP (GFRP) bars in the literature. The results indicated that BFRP bars exhibit relatively good resistance to alkaline corrosion, maintaining more than 60% of their original strength after 9 weeks at 55 ° C in an alkaline solution. The moisture absorption of BFRP bars conforms to Fick ' s law, which shows that the degradation mechanism is controlled by matrix and related interface degradation. This finding is supported by comparison with the shear strength degradation trend. Compared to GFRP bars under similar alkaline conditions, BFRP bars exhibit a similar degradation rate during the initial phase, but maintain higher tensile strength and strength retention over time.

Bond-Slip Behavior of Basalt Fiber Reinforced Polymer Bar in Concrete Subjected to Simulated Marine Environment: Effects of BFRP Bar Size, Corrosion Age, and Concrete Strength

“…Numerous researches have been carried out on mechanical properties and bond durability of BFRP bars or BFRP reinforced concrete [11][12][13][14]. The tensile strength loss of BFRP bars was as high as 40% after immersion in 55 ∘ C alkaline solution for 63 days [11], and the bond strength of BFRP bars in concrete immersed in artificial seawater for 90 days exhibited a 25% reduction [12]. Tighiouart et al [13] confirmed that it was easy bleeding at the interface between BFRP bars and concrete when the large diameter BFRP bars were used, resulting in a decreased bond strength between BFRP bars and concrete.…”

“…It should be noted that the bond-slip behavior of BFRP bars in concrete was different from that of steel bar [16,17]. Although some achievements about the bond-slip behavior between BFRP bars and concrete have been made [11,[16][17][18][19][20][21][22][23][24], most of them were focused on small size BFRP bars (<B 10 mm). However, the bond-slip behavior between large size BFRP bars and concrete is different due to larger interfacial transition zone, internal bleeding, and smaller specific perimeter.…”

Halloysite nanotube reinforcement endows ameliorated fracture resistance of seawater aged basalt/epoxy composites

“…As summarized in Figure 8(c), the shear strength of the basalt–neat epoxy composite laminate is calculated as 36.1 MPa before the seawater aging which is comparable with the literature. 38–40 The addition of 2 wt% HNTs in the epoxy matrix is found to increase the shear strength up to 42.9 MPa, which is approximately 19% higher than that of the control sample. It is clear that the ILSS decreases gradually with the increasing aging time, and the reduction in ILSS for the neat basalt–epoxy and the hybrid composite is calculated as 52.3 and 39.5%, respectively, after six-month seawater aging.…”

Degradation of basalt fiber–reinforced polymer bars in seawater and sea sand concrete environment

“…As shown in Figure 3(a), the surface condition of the bar changes after 63 days of immersion in the alkaline solution at 32°C. The surface of the bar is corroded, as suggested by Wu et al, 39 due to etching. Similarly, in Figure 3(b)-(d), it can be seen that the depth of corrosion has accelerated to a greater extent with the increase in exposure temperature.…”