Flexural behavior of two-span continuous prestressed concrete girders with highly eccentric external tendors

[Abstract]: It is generally known that the flexural strength of beams prestressed with external tendons is comparatively lower than that of members with internal bonded tendons. One possible method of enhancing the flexural strength of such beams is to place the tendons at high eccentricity. To obtain an insight into the flexural behavior of beams with highly eccentric tendons, an experimental investigation is conducted on single-span and two-span continuous beams. The test variables include external tendon profile, loading pattern on each span, casting method, and confinement reinforcements. It is found that continuous girders with linearly transformed tendon profiles exhibit the same flexural behavior irrespective of tendon layout. The presence of confinement reinforcement enhances the ductility behavior but does not increase the ultimate flexural strength. The degree of moment redistribution is affected by the tendon layout and the loading pattern on each span. The results of the experimental investigation are discussed in this paper

EXPERIMENTAL STUDY ON SHEAR CRACKING BEHAVIOR IN I-SHAPED PARTIALLY PRESTRESSED CONCRETE BEAMS

ABSTRACT An experimental program was conducted to investigate the shear cracking behavior in I-shaped reinforced concrete and I-shaped partially prestressed concrete beams. All beams were tested under four point static monotonic loading by focusing on the influence of compressive stress in concrete due to prestress, stirrup ratio, side concrete cover, type of stirrup and longitudinal reinforcement ratio on the shear crack width. During the loading test, shear crack width was monitored close to stirrup strain gage attached by using digital microscope

ANALYSIS OF SHEAR CRACKING BEHAVIOR IN PARTIALLY PRESTRESSED CONCRETE BEAMS

ABSTRACT This paper presents an analytical simulation of shear cracking behavior of partially prestressed concrete beams using a numerical model, based on the Modified Compression Field Theory (MCFT). It is shown that this model can predict experimental results of the load displacement relationship, flexural cracking load, diagonal cracking load, stirrup strain, principal tensile strain, shear crack width, final failure crack pattern and failure mode consistently and satisfactorily