Effect of sleeve length on deformation properties of grouted splices
Tests on 12 grouted splices were performed to investigate their deformation properties under tensile loading. Test variables included diameter and type of spliced bars and the size of splicing sleeves. Finite element method based models of the splices were built, verified and used to investigate the effect of sleeve length on the deformation properties of the grouted splices. The sleeve length significantly affected the failure modes and further affected the splices’ deformation properties. A recommendation was proposed to maximize deformation properties of a specific splice by using a critical sleeve length associated with failure mode of bar fracture.
GROUTED SLEEVE CONNECTION FOR PRECAST
Precast concrete structures have gained preference in the modern construction industry because of the multiple advantages they offer. The connection of precast members is an important aspect to consider in the design of structures with precast components. Grouted Sleeve connection, one of the famous connector types, is made of the trio of reinforced bars, high strength grouting materials and a ductile iron cylinder. This article compares the finding of recent experimental research findings on grouted sleeve connection and establishes the relationship between the three components of the connector to enhance the performance of the splicing agent. It is found that the tensile performance of the connector increases with the embedded length of the bar for a normal sleeve. An effective embedded length set between 6 and 8 times the diameter of the bar will maximize the tensile performance of the connector. The increase in diameter of the sleeve cylinder, the compressive strength of the grout and the length of the bar embedded and its surface will affect the bond performance and the mode of failure under tensile load. `
Toward an Improved Understanding of Shear-Friction Behavior
Through an in-depth review of previous work complemented by an experimental study, the nature of shear-friction behavior is studied. It is shown that the ACI 318-08 and AASHTO approaches to shear friction do not capture the actual behavior and imply incorrect limit states. A simple explanatory model and modifcations to the form of empirical design equations are proposed. A large number of parameters affect shear-friction performance. This study does not attempt to address them all but rather illustrates the fundamental shear-friction behavior. This study does, however, consider the use of high-yield-strength reinforcing steel (ASTM A1035/A1035M). In doing so, the serious limitations of the design equations are illustrated. Additionally, this study is the only known study of shear-friction behavior to include high-strength steel.