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.

Because of the shortcomings of the externally bonded system that mainly consists of epoxy and FRP sheets, the fabric-reinforced cementitious matrix, (FRCM) represents a viable solution in the strengthening of reinforced concrete beams. The FRCM layers consist of fabric mesh embedded in an inorganic stabilized cementitious mortar. Many experimental studies examined the impact of strengthening of RC beams with the FRCM layers, but the numerical investigations are limited. This study is therefore aimed at introducing a numerical study investigating the behavior of RC beams reinforced with FRCM layer. The main goal of this paper is to verify the FEM results with the experimental results that are available in the previous study [1], and to provide a parametric study. The investigated beams in this paper are 150 mm × 250 mm× 3000 mm with two reinforcement ratios. One, two, and three-layers of PBO, (P-Phenylene Benzobis Oxazole) FRCM were investigated as strengthening of the simulated beams were strengthened with. The numerical validation included load-deflection curve, loadstrain of both concrete and PBO-FRCM, strain distribution, cracks series and failure Mohamed Nagah et al., Nonlinear Finite-Element Analysis for Rc Beams Strengthened…… mode. The built model gave an accurately prediction of the attitude of the investigated beams. The results also indicated that the rise in the reinforcement ratio or the amount of FRCM layers contributed to improving behavior under both ultimate and serviceability limit states.

Abstract. In Japan, old RC bridge-deck slabs were economically designed by small thickness without considering the fatigue resistance. These slabs are subjected to a huge repetition of moving loads. Therefore, they are suffering from fatigue damage. This damage is more significantly observed than that of slabs reinforced with deformed bars. To extend their fatigue life, a suitable strengthening technique is required such as externally bonded FRP sheets. Using numerical method for predicting the improvement in their fatigue life is strongly beneficial to take full advantage of this strengthening technique. This study presents a proposed numerical method based on bridging stress degradation concept to analyze two full scale RC slabs reinforced with plain bars under moving load. One of them is strengthened with externally bonded FRP sheets in longitudinal and transverse directions on the slab bottom surface. The interfacial bond behavior between FRP sheet and concrete surface with its degradation due to fatigue loading is implemented. This study provides the propagation of cracked elements, center displacement evolution, cracking pattern and FRP strain. For the strengthened RC slab, the major crack opening is restricted by the contribution of FRP sheets in longitudinal and transverse directions. Therefore, the strengthened RC slab shows longer fatigue life and smaller deformation. By comparing these numerical results with the experimental results, the current numerical method provides a good agreement.

Many numerical and experimental studies have been conducted to predict the fatigue life of RC slabs under moving load. Most of these works study the modeling of fatigue behaviors of RC slabs reinforced with deformed bars. The current study presents an experimentally verified numerical method to simulate the fatigue behaviors of RC slabs reinforced with plain bars under moving load. This numerical method is based on the bridging stress degradation concept. The bond-slip effect between a reinforcing bar and surrounding concrete is taken into consideration under repetitive load. The fatigue behaviors of RC slabs under moving load can be simulated through this numerical method. This method is also able to capture the cracking pattern, displacement evolution and rebar strain. The numerical method shows a good agreement with the experiments under static and moving load.

Steel plate girders with trapezoidal corrugated webs (TCWPGs) have been used over the last years around the world in many roadway and railway steel bridges as they can introduce several important advantages compared to flat web plate girders. The proper design of corrugated web girders depends mainly on the flexural and shear capacity of them. However, the flexural capacity is more important. Also, not many researchers studied the flexural capacity of such girders especially, when flange local buckling failure type (FLB) occurs in these corrugated web girders. In this paper, the flange local buckling behavior of steel trapezoidal corrugated web girders built up from highstrength steel (HSS) plates has been investigated to get the advantages of both KEYWORDS: Flexural behavior; flange local buckling (FLB); trapezoidal corrugated web (TCW); high-strength steel (HSSs); ABAQUS/CAE.