Genç, Ali Fuat; Nasery, Mohammad Manzoor; Cosgun, Suleyman Istemihan; Yalçınyavuz, Azapay Ümmühan

This study presents a numerical damage simulation of a historical masonry aqueduct at the Sümela Monastery (Virgin Mary) under rockfall. This monastery site has a sharp topography and is exposed to significant rockfall risk. In recent years, local authorities have implemented safety applications, including controlled blasting, anchoring, and cleaning to identify the risky blocks and eliminate rockfall risks. Rockfall risk analyses were conducted considering the topographic features of the site to simulate damage caused by natural rockfalls and those induced by the safety measures employed at the site. Numerical impact analyses were conducted to investigate the resulting damage on the historical aqueduct after determining rockfall risks. In these analyses, four different rock volumes were dropped at the midpoint of each arch. The results of the impact analyses indicated that low-volume rocks (e.g., 0.06–0.09 m3) induced localized surface damage, whereas rocks with larger volumes (2.5–5.0 m3) caused more extensive global failure patterns. The results clearly demonstrate the destructive effects of rockfall on the structure. Finally, this study discusses post-disaster landscape planning for a site that receives thousands of visitors annually.

Cosgun, S.I.; Kaya, A.; Gencturk, B.

Steel columns or piles commonly used in bridges and marine structures in various parts of the world exhibit insufficient strength due to increased load demands or section loss due to corrosion. The latter issue can cause unexpected buckling of these columns. In this study, the repair of corroded and buckled short steel piles using concrete-filled GFRP jackets was numerically simulated to better understand the overall effectiveness of the method and the influence of the parameters involved. Thirteen steel piles used in this study had different degradation characteristics to investigate the section losses affecting the axial capacity and failure modes. The parameters considered included the presence or absence of concrete steel reinforcement (rebar), the diameter of the rebar, the number of GFRP layers, the location of the worn zone in the steel section and the severity of the section loss. The numerical models were validated using these experimental results of the repaired specimens from the authors’ earlier work on the topic. The main contribution of this study is in the development of the numerical models that can very accurately simulate the ultimate strength and damage behavior of retrofitted piles that are heavily corroded and buckled. The validated models were used in a parametric study to understand the effects of different levels of concrete strength, or corrosion of the piles in the flanges, the web, or both. The results of the parametric study provided further understanding of the structural behavior of degraded and strengthened steel piles.