KISIN, ALEKSANDAR1; FELDMAN, LISA R.2;

1) M.Sc. Student, University of Saskatchewan, Department of Civil & Geological Engineering, alk102@mail.usask.ca

2) Associate Professor, University of Saskatchewan, Department of Civil & Geological Engineering, lisa.feldman@usask.ca

A previous investigation at the University of Saskatchewan compared the tensile capacity of contact lap splices and non-contact lap splices, with the spliced bars located in adjacent cells. The results showed that non-contact lap splices developed only 71% of the tensile capacity of spliced bars which were in contact. These results warranted a subsequent research project to design and assess remedial measures which can potentially increase the tensile capacity of non-contact lap splices to that of contact lap splices. The viability of implementing the proposed measures in various field situations was also examined. Wall splice specimens with six separate mitigative details were tested to determine the effects of adding additional confinement, installing knock-out webs, or placing splice reinforcement between the lapped bars. Combinations of the aforementioned details were also evaluated. Wall splice specimens with standard contact and unaltered non-contact splice details were constructed and used as controls. The specimens were tested in a horizontal position with monotonically applied four-point loading. The structural performance of each remedial splice detail was established based on the analysis of the measured experimental data. Establishing viability of field implementation included consideration of the construction process, consultations with industry professionals, and requirements of each remedial splice detail. Multiplication factors were then proposed to represent the available tensile resistance of all reasonable remedial cases.

Wall splice specimens containing non-contact lap splices with knock-out webs, s-shaped, and transverse reinforcement in the splice region resulted in similar tensile capacities as the control wall splice specimens featuring contact lap splices. The remedial procedure that only included knock-out webs between the lapped bars was determined to be the most viable procedure to increase the resistance of non-contact lap splices in construction situations.

Keywords: Bond, lap splices (contact & non-contact), concrete block construction, field implementation, knock-out webs, transverse reinforcement