The hysteretic behavior and seismic characteristics of the prestressed concrete bridge pier were researched. The effects of the prestressed tendon ratio, the longitudinal reinforcement ratio, and the stirrup reinforcement ratio on the hysteretic behavior and seismic characteristics of the prestressed concrete bridge pier have been obtained with the fiber model analysis method. The analysis show...

Concrete has been prestressed traditionally with high-strength steel. The vulnerability of such material to corrosion calls for alternate materials, if thin-sheet products are to be prestressed. A research project at Columbia University is investigating the feasibility of using aramid fiber mesh for such purpose. This paper explores the chemical and mechanical properties of aramid in the form o...

D analyses of structures responding elastically to ground motions recorded during severe earthquakes have shown that the theoretical response inertia loads are generally significantly greater than the static design lateral loads recommended by codes. Hence, structures designed for the lateral earthquake loads recommended by codes can only survive severe earthquakes if they have sufficient ducti...

In this paper, moment-curvature behavior and ductility of prestressed concrete members based on nonlinear analysis is investigated. Influence of various design parameters on ductility of flexural members is determined according to appropriate materials models for stress-strain curves of concrete, prestressing steel and conventional reinforcements. Parameters studied include reinforcing index (ω...

In this paper, the bi-directional evolutionary structural optimization (BESO) method is used to find optimal layouts of 3D prestressed concrete beams. Considering the element sensitivity number as the design variable, the mathematical formulation of topology optimization is developed based on the ABAQUS finite element software package. The surface-to-surface contact with a small sliding between...

Since the 1950’s, prestressed concrete beams have become a factor in almost one third of all new bridge construction in the United States. In Michigan, prestressed concrete was introduced in 1954 and the first prestressed concrete side-by-side box-beam bridge was built in 1955. Pontis data indicates 2,054 side-by-side prestressed concrete box-beam bridges in Michigan; 236 are part of the Nation...

................................................................................................................................. i Dedication........................................................................................................................... iii Acknowledgements............................................................................................................. i...

the current study is focused on strengthening of reinforced concrete (rc) beams using cfrp straps installed in pre-cut grooves. the method which is referred as near surface mounted (nsm) benefits considerable advantages in comparison with the conventional externally bonded reinforcement (ebr) method and provides better normal and shear stress transfer between the frp and concrete substrate. the...