In existing bridge structures, reinforced concrete dapped-end beams/girders (RCDEB) are frequently subjected to service loadings that exceed their design capacity, due to increasing economic and population growth. Dapped-end beams are prone to the accumulation of water due to improper drainage and sealing of the joint, providing favorable conditions for corrosion due to the stagnation of chloride rich water from de-icing salts used on roads. The situation can get even worse when freezing and thawing due to extreme weather conditions is present. Due to difficulties in maintenance of the dapped-end regions, this often leads to the deterioration of the concrete around the recess and bond deterioration, which ultimately results in durability issues. Unfortunately, the performance of RCDEB exhibiting corrosion induced bond deterioration is still not well understood. Hence, experimental, and numerical investigations were conducted to understand better the response of RCDEB subjected to static and cyclic loading, with the presence of bond deterioration. Furthermore, the static capacity of the beam was adopted to consider the variable amplitude cyclic loading at an increment of 15% static capacity for every 20 cycles. The reliability of the numerical examination under the direct-path constitutive models of concrete was extended to the moving load scenario by applying a lower load amplitude than the static capacity. It is shown that the prominent failure mechanisms observed in both static and cyclic tests were diagonal tension and shear. Through numerical investigations, it is also shown that from the damage level developed in the RCDEB under the moving load at a relatively low magnitude, high stresses were found within a relatively short number of cycles, which raises a serious cause for concern.
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