Durability study on glass fiber reinforced polymer soil nail via accelerated aging test and long‐term field test

Abstract

Replacing steel reinforcements with glass fiber reinforced polymer (GFRP) bars has emerged as one of the most promising solutions to the problem of corrosion in geotechnical engineering. Accelerated aging and field tests were conducted to investigate the durability of GFRP bars that were used as soil nails in slope reinforcement. Two types of E‐glass/(vinylester and unsaturated polyester) were immersed in alkaline and saline solutions for 60 d, 180 d and 360 d. Mechanical and physical experiments were carried out to obtain the tensile strength and identify the reasons for damage and strength reduction. A pullout test was carried out after the GFRP soil nails were embedded in a slope for three years. The accelerated aging test results showed that alkaline conditions had a larger influence on the degradation of GFRP bars than did saline solutions and that strength reduction generally occurred at an earlier stage for the alkaline conditions than for the saline solution. The corrosion resistance of an unsaturated polyester bar is much lower than that of the vinylester bar, and the bar diameter has a certain impact. From the field test results, it can be seen that the GFRP soil nails are durable and perform well at the task of supporting a slope. The technology for sensing fiber Bragg gratings (FBG) is very convenient for monitoring soil nails and is suitable for long‐term observation. POLYM. COMPOS., 38:2863–2873, 2017. © 2015 Society of Plastics Engineers

Synergistic environmental degradation of glass reinforced polymer composites

“…Numerous studies have focused on the environmental degradations of Polymer Matrix Composites (PMCs) in general, and more specifically, aging of Glass Reinforced Polymer (GRP) composites caused by a large variety of aggressive environments. Some of the most recent studies can be found in [1][2][3][4][5][6]. Very few of them, however, have dealt with the synergistic effects of aging of polymers and GRPs under combinations of several aging conditions [6,7 and 8].…”

A Study on Au(I)‐thiolate Nanosheets as Water‐dispersible UV Absorbents

“…In recent years, it is believed that the harm of UVA to human cannot be ignored, because UVA has the strong ability to penetrate clothing and reach the dermis, not only destroying lipids and collagen and darkening human skin, but also leading to the DNA damage and cancer [16–19] . Besides the harms to human, UV radiation will accelerate the aging of organic and polymer materials and shorten their service time too [20–24] . Therefore, protection of people and materials from UV irradiation is particularly important.…”

Effects of seawater absorption and desorption on the long‐term creep performance of graphene oxide embedded glass fiber/epoxy composites

“…[3][4][5][6] There are three main mechanisms, which govern the water absorption in a GFRP composite: water diffusion into polymer matrix, diffusion at the interfaces of fiber/matrix, and capillary uptake by voids, while water uptake by glass fibers is quite insignificant. [7] The absorbed water primarily affects the state of the polymeric matrix and fiber/matrix interphase regions by inducing both irreversible and reversible alterations in the microstructure of the matrix through plasticization, hydrolysis, or saponification, thereby adversely affecting their mechanical, chemical, and thermophysical properties. [8] In the past several years, different research groups have attempted to study the durability and performance of glass fiber laminated composites when exposed to various water media, such as distilled water, tap water, seawater, and so on.. [9] Aldajah et al [10] have reported reductions of 60% and 55% in the flexural stiffness of symmetric GFRP composite laminates when subjected to tap water and sea water conditioning, respectively, for 2000 hours.…”

“…[ 3–6 ] There are three main mechanisms, which govern the water absorption in a GFRP composite: water diffusion into polymer matrix, diffusion at the interfaces of fiber/matrix, and capillary uptake by voids, while water uptake by glass fibers is quite insignificant. [ 7 ] The absorbed water primarily affects the state of the polymeric matrix and fiber/matrix interphase regions by inducing both irreversible and reversible alterations in the microstructure of the matrix through plasticization, hydrolysis, or saponification, thereby adversely affecting their mechanical, chemical, and thermophysical properties. [ 8 ]…”