Fatigue Analysis of RC Slabs and Repaired RC Slabs Based on Crack Bridging Degradation Concept

2016

ACT

Self Cite

Journal of Advanced AbstractThere is an increasing demand from researchers and engineers to know the fatigue behaviors of RC bridge slabs under a moving load. Therefore, many numerical and experimental studies have been conducted to predict the fatigue life of these slabs. Most of these studies focused on the modeling of fatigue behaviors of RC slabs reinforced with deformed bars. However, many RC slabs in use today are reinforced with plain bars, and they are suffering from fatigue damages. A numerical method based on the bridging stress degradation concept is presented in this study to simulate the fatigue behaviors of RC slabs reinforced with plain bars under a moving load. The bond-slip effect between a reinforcing bar and its surrounding concrete is taken into consideration by adding equivalent bond strain to plain bar strain. The numerical model is verified using previous experimental data. This model is also able to capture the cracking pattern, change in displacement and rebar strain. The numerical results provide a good agreement with the experimental ones.

Section: Concretementioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Fatigue Analysis of RC Slabs Reinforced with Plain Bars Based on the Bridging Stress Degradation Concept

Drar

2016

ACT

Self Cite

“…Subsequently, the fatigue life prediction and evaluation of road bridge RC slabs have been discussed (Abe 2015). In addition, researchers have investigated analytically the dominant degradation mechanisms (Suthiwarapirak et al 2006;Drar et al 2016;Deng et al 2018) and fracture me-chanics (Deng et al 2019) of RC slab fatigue. The fatigue-induced structural deterioration has also been assessed numerically by Huang (Huang et al 2021).…”

Section: Introductionmentioning

confidence: 99%

Image Analysis for Deformation Behaviors of RC Beams with Simulated Deteriorations under Moving Wheel Load

Nagai

Deng

2022

ACT

Self Cite

In Japan, RC bridges slabs constructed during the high economic growth period are suffering from severe deteriorate due to fatigue. In cold and snowy regions, in addition to fatigue, the deterioration is accelerated and aggravated simultaneously by freeze-thaw cycles and water penetration simultaneously. Hence, in this study, aiming at investigating the deterioration due to this combined action, three RC beams were artificially damaged on the top surface by introducing expansion agents to simulate the freeze-thaw cycle damages beforehand, and then subjected to moving wheel load under either dry or wet condition. In the experiment, a scaling-off and a disintegration were observed on the top surface due to the existence of water. Besides, to facilitate the elucidation of the mechanisms, image analysis was employed to obtain the displacement distributions and strain distributions on the side surfaces of the specimens during the test. The results of image analysis clearly manifested that the water-induced deteriorations lead to a localized compressive strain on the upper part of the beams as well as detrimentally affected the propagation of the shear and bending cracks under the moving wheel load. In summary, the mechanical reasons of the remarkably shortened fatigue life of artificially damaged RC bridge slabs due to combined fatigue loads and water penetration were uncovered in this study taking advantage of the strengths of image analysis, which also provides reference and inspiration for further related studies.

“…Li and Matsumoto (1998) introduced the bridging stress degradation concept in the crack growth analysis of fiber reinforced concrete. Based on this concept, a numerical model for analyzing the fatigue behaviors of the panel RC slabs was developed, with which the fatigue life was predicted successfully (Suthiwarapirak and Matsumoto 2006). The bridging stress degradation concept was further extended to analyze the fatigue behaviors of the panel RC slabs reinforced with plain bars (Drar and Matsumoto 2016).…”

Section: Introductionmentioning

confidence: 99%

Approximate Analytical Conditions of a Panel RC Slab for Reproducing the Fatigue Behaviors of a Real Bridge RC Slab

Khan

Deng

2020

ACT

Self Cite

This study proposes approximate boundary conditions for a panel reinforced concrete (RC) slab to simulate the fatigue behaviors of a real bridge RC slab. To validate the approach, fatigue analysis of the panel RC slab is conducted using a finite element method (FEM) based numerical model with the bridging stress degradation concept. Both the proposed approximate boundary conditions, and those that have been typically employed in past studies, are used. The numerical results demonstrate that the panel RC slab with approximate boundary conditions experiences the same bending moment distribution and deformations around the loading locations as the load moves along the slab axis, similar to those of a real bridge RC slab. Moreover, the approximate boundary conditions reproduce the extensive grid crack pattern in the panel RC slab, which is similar to that generally observed in a real bridge RC slab. The results of this study establish that panel RC slab with approximate boundary conditions behaves in a similar manner to a real bridge RC slab, which results in a more realistic fatigue life estimation.