Fatigue Life Dependency on the Cleanliness and Ductility of Structural Steels

[摘要] Plain concrete is very brittle and weak. It cannot withstand sudden shock, cyclic load and high level of tensile stress. So, concrete is reinforced by various types of structural steels. To reduce the overall weight of the RCC structures, worldwide practice is to use high strength structural steels along with high strength concrete. In this research work low strength high ductility (300 grade) and high strength moderate ductility (500 grade) locally produced steel bars of 20mm diameter were used. They were then characterized by means of chemical composition, microstructure, size and distribution of inclusion particles, tensile and fatigue tests. The fracture surfaces of the failed fatigue samples were observed under optical and scanning electron microscopes. After detail investigation, experimental results suggest that compared to ductility, cleanliness of the structural steel bars are much more important for better fatigue life of the RCC structures.

[发布机构] Department of Materials and Metallurgical Engineering, Bangladesh University of Engineering and Technology, Dhaka; 1000, Bangladesh^1;Department of Mechanical and Aerospace Engineering, George Washington University, Washington; DC; 20052, United States^2

[关键词] Chemical compositions;Fracture surfaces;High strength;High strength concretes;High-strength structural steels;Inclusion particles;Plain concrete;Structural steels