STRENGTH BEHAVIORS OF PRESTRESSED CONCRETE SLEEPERS WITH CRACK RESISTING STIRRUPS

Abstract

This research investigates the effects of stirrups on shear strength and cracking behaviors in Prestressed Concrete Sleepers (PCSs). A total of five PCSs with a cross-section of 258 × 205 mm with varied stirrup’s ratio of 0.4 to 1.0 % (a stirrup’s spacing of 30, 60 and 90 mm) were subjected to statically three-pointed bending load. Shear strength of PCSs with stirrups can be enhanced from 5.5 to be more than 15.7 %, whereas ductility of PCSs with stirrups can be enhanced from to 32.7 to 70.7%, compared to PCS without any stirrup. When increasing stirrup’s ratio to 1.0 % in PCSs, failure modes of PCSs was shifted from shear or shear-flexural to flexural failures. PCSs with rounded-bar stirrups also showed more severe shear cracks than that in PCSs with deformed-bar stirrups, proving higher bonding interface between concrete and stirrups due to ribs of the deformed bars. These significantly indicate the optimized stirrup’s ratio and proper type of steel stirrups for PCS’s design in the future.