Fatigue Damage Behaviors of TRC-Strengthened RC Beams

Abstract

For the investigation of fatigue damage behavior of textile reinforced concrete (TRC)-strengthened RC beams, in this study, eight RC beams were fabricated, and five of them were strengthened with TRC and tested under fatigue loading until failure, using a four-point bending setup. Research parameters included reinforcement ratio, textile ratio, and strengthening methods (single-side and U-wrapped). The failure mode, fatigue life, fatigue deformation, and other properties of TRC-strengthened beams were analyzed. Experimental results revealed that there were two fatigue failure modes for TRC-strengthened RC beams. In the first mode, the textile was snapped, but the steel bars did not rupture. In the second mode, both the textile and steel bars broke. Fatigue failure modes depended on the textile ratio. The TRC-strengthened beam’s fatigue life was significantly higher than the non-strengthened RC beam. At the same textile ratio, the TRC-strengthened beam’s fatigue life using the single-side method was longer than that using the U-wrapped method. With the increase in fatigue loading time, the midspan deflection of the TRC-strengthened beam was developed in three stages, namely rapid development stage, stable development stage, and destabilized development stage. The residual deflection and strain damage accumulation of tensile steel bars of TRC-strengthened beams were significantly reduced with the increase in textile or reinforcement ratios; thus, the beam’s fatigue life was prolonged.

Nâng cao hiệu quả của bê tông cốt lưới dệt (TRC) đối với dầm bê tông cốt thép được gia cường: Nghiên cứu về sự phát triển vết nứt và liên kết vật liệu

“…Các nghiên cứu hiện nay chủ yếu tiến hành thử nghiệm độ bền và đánh giá tính chất cơ học của TRC. Một số thí nghiệm thực tế dựa trên thông số đầu vào cụ thể của một loại TRC cho trước và dạng tải trọng cho trước, từ đó đánh giá khả năng chịu lực, độ bền với môi trường ăn mòn và khả năng chịu nứt của dầm bê tông cốt thép gia cường bằng TRC [5][6][7]. Kết quả nhận được đều cho thấy TRC có thể cải thiện sự chịu tải của dầm và giảm thiểu vết nứt.…”

Mechanical Properties of Fire-Damaged RC Beams Reinforced with Carbon Fiber Mesh

“…The fatigue life of TRC-reinforced beams was significantly superior to that of RC beams without reinforcement. Under the same texture ratio, the fatigue life of single-sided TRCreinforced beams was longer than that of U-shape TRC-reinforced beams [10]. In addition, the flexural and crack behaviors of concrete beams reinforced with bottom ash and fly ash was examined [11].…”

A Review on Nonlocal Theories in Fatigue Assessment of Solids

“…It provides a macroscopic field variable that reflects the average microstructural material damage [ 20 , 21 ]. This so-called “damage variable” appears in the constitutive relations that regulate a material’s deformation behavior [ 22 ]. At the crack initiation stage, the damage variable grows progressively under the impact of mechanical loading.…”